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Wednesday, May 26, 2010
Friday, April 16, 2010
Virology is the study of viruses.
Prokaryotic viruses are classified by nucleic acid type, nucleic acid strains, and if they have an envelope (if so…what type). They have strange nucleic acid configuration and unusually bases. For example, cytosine is 5 Hydroxymethylcytosine. They can be d-s DNA (bacteriophage), s-s DNA (plants), d-s RNA, and s-s RNA.
A virion consists of either DNA or RNA, and has a protein coat. Virions are extracellular and have few enzymes, and cannot reproduce without a host.
All virions are surrounded by a capsid. The capsid is either RNA or DNA and held with a coat called protein capsid. The proteins used to build the capsid are called protomers.
• The tobacco mosaic virus is constructed using a single type of protomer. TMV has 6,000 nucleotides, but only uses about 475 to code for the coat protein
• Hersey and Chase used a virion.
One type of capsid is called icosahedral. They are very complex and have an envelope. A T-even phage is icosahedral and has an envelope. A T-even phage is d-s DNA bacteriophage, with multiple tails. The tails contract and inside the tail ATP is found. The tail injects its DNA into host cell.
An envelope is common in plants, animals and virus and is bound to an outer membrane layer. Enveloped viruses develop from the hosts nuclear or plasma membrane. Some have spikes, which project from the envelope, and they are used for attachment. Influenza virus has an envelope, and neuraminidase is used to break down the host membrane.
A bacteriophage is a virus that infects bacteria. E. coli (T-even phage) can be infected by 20 different phages. The phage is made up of DNA or RNA and protein capsid. D-S DNA is most commonly found, and is classified on nucleic acid properties and phage property.
After the DNA of the bacteriophage has reproduced within the host, many of them are released when the cell is destroyed by lysis. The bursting is the lytic cycle, and only virulent viruses reproduce this way. The lysis enzyme is phagelypozme, which breaks apart the peptidoclygcan layer.
Plaque is areas on the dish where lysis has occurred. Animal viruses cause degenerative changes in the host cell and in tissues. This is called the cytopathic effect. Cytopathic viruses do not produce plague and cell lysis doesn’t occur.
One step growth experiment:
The x plot is time and the y is plague count. The first stage is the latent period
Receptor sites are found on the host cell where bacteriophage’s attach. Receptors are found on cell walls, flagella and pili. For example, when T-even phage attaches to E. coli, it injects DNA into it. Protein, DNA, and RNA synthesis is shut down in the host.
The first response before DNA is recognized by the promoter is early mRNA. RNA polymerase will only start making viral mRNA. Early mRNA directs host (E. coli) to produce the phage proteins, enzymes, and make viral nucleic acid. This degrades the host DNA. The T4 phage then uses the E. coli nucleotides to make its own DNA.
Before DNA replication starts the bases are different and needs two additional enzymes. They are ?????. Glucose must be added at the end to protect the T-even DNA
S-S RNA phages can also act as m-RNA to synthesis proteins. RNA replicase is needed to copy the original strands of tRNA. This produces the replicative form. This severs as a temple for RNA replication.
Types of RNA phages are MS2, QB, and only code for 3-4 proteins, where was a T-even phages codes for 100 proteins.
Temperate bacteriophage can either lysis or stay in the host without destroying it. These phages have immunity to super infections. They alter the bacteria surface and nothing can be attached to the receptors. A temperate phage with allow no other phage to enter.
The relationship with the temperate phage and the host is known as lysogeny.
A form of a phage that can remain in the host are called prophage. It is the latent form of the viral genome host. When lambda sits on the genome it is a prophage. When lambda comes off the genome the process is called induction, therefore entering the lytic cycle, and release of new phages.. For example, UV lyses cells and these bacteria are known as lysogenic.
Lambda is a d-s DNA phage, that has a tail that doesn’t contract, and an icosahedral head. Its genome is linear, complimentary base pairs, with 2 cohesive ends. When lambda enters the host ligase connects the cohesive ends and makes the genome a circle. Lambda is a prophage.
During the lytic cycle, ligase is transforming the genome into a circle. Also, regulatory genes are the first to become transcribed because they control the lytic cycle. Transcription occurs either clockwise for counter clockwise.
For lysogeny to occur and not the lytic cycle, lambda needs a repressor. Lambda binds to the operator to block RNA polymerase activity. RNA synthesis of lambda doesn’t happen. The Cro protein binds to the operator, which tries to turn off transcription of the repressor gene.
In order for lysogeny to occur higher levels of Cro are needed. The lambda DNA can then insert itself inside the genome. The insertion enzyme is intergrase, and has a particular attachment site. The attachment sites are the gal and biotin operons. Lambda is a prophage.
Eukaryotic virus are characterized by morphology, DNA, or RNA, and how they are related genetically.
Eukaryotic viruses penetrate with fusion of cell membrane receptors (or envelope), releasing its nucleic acids, and removing its capsid.
In early genes the virus takes on host, and early mRNA is transcribed. Then viral DNA or RNA is made.
The late genes make capsid proteins, by self assembly. DNA can then enter.
Specific eukaryotic viruses are classified in 4 groups, and is based on replication and transcription relation to the host genome. For example, poliovirus
A virion consists of either DNA or RNA, and has a protein coat. Virions are extracellular and have few enzymes, and cannot reproduce without a host.
All virions are surrounded by a capsid. The capsid is either RNA or DNA and held with a coat called protein capsid. The proteins used to build the capsid are called protomers.
• The tobacco mosaic virus is constructed using a single type of protomer. TMV has 6,000 nucleotides, but only uses about 475 to code for the coat protein
• Hersey and Chase used a virion.
One type of capsid is called icosahedral. They are very complex and have an envelope. A T-even phage is icosahedral and has an envelope. A T-even phage is d-s DNA bacteriophage, with multiple tails. The tails contract and inside the tail ATP is found. The tail injects its DNA into host cell.
An envelope is common in plants, animals and virus and is bound to an outer membrane layer. Enveloped viruses develop from the hosts nuclear or plasma membrane. Some have spikes, which project from the envelope, and they are used for attachment. Influenza virus has an envelope, and neuraminidase is used to break down the host membrane.
A bacteriophage is a virus that infects bacteria. E. coli (T-even phage) can be infected by 20 different phages. The phage is made up of DNA or RNA and protein capsid. D-S DNA is most commonly found, and is classified on nucleic acid properties and phage property.
After the DNA of the bacteriophage has reproduced within the host, many of them are released when the cell is destroyed by lysis. The bursting is the lytic cycle, and only virulent viruses reproduce this way. The lysis enzyme is phagelypozme, which breaks apart the peptidoclygcan layer.
Plaque is areas on the dish where lysis has occurred. Animal viruses cause degenerative changes in the host cell and in tissues. This is called the cytopathic effect. Cytopathic viruses do not produce plague and cell lysis doesn’t occur.
One step growth experiment:
The x plot is time and the y is plague count. The first stage is the latent period
Receptor sites are found on the host cell where bacteriophage’s attach. Receptors are found on cell walls, flagella and pili. For example, when T-even phage attaches to E. coli, it injects DNA into it. Protein, DNA, and RNA synthesis is shut down in the host.
The first response before DNA is recognized by the promoter is early mRNA. RNA polymerase will only start making viral mRNA. Early mRNA directs host (E. coli) to produce the phage proteins, enzymes, and make viral nucleic acid. This degrades the host DNA. The T4 phage then uses the E. coli nucleotides to make its own DNA.
Before DNA replication starts the bases are different and needs two additional enzymes. They are ?????. Glucose must be added at the end to protect the T-even DNA
S-S RNA phages can also act as m-RNA to synthesis proteins. RNA replicase is needed to copy the original strands of tRNA. This produces the replicative form. This severs as a temple for RNA replication.
Types of RNA phages are MS2, QB, and only code for 3-4 proteins, where was a T-even phages codes for 100 proteins.
Temperate bacteriophage can either lysis or stay in the host without destroying it. These phages have immunity to super infections. They alter the bacteria surface and nothing can be attached to the receptors. A temperate phage with allow no other phage to enter.
The relationship with the temperate phage and the host is known as lysogeny.
A form of a phage that can remain in the host are called prophage. It is the latent form of the viral genome host. When lambda sits on the genome it is a prophage. When lambda comes off the genome the process is called induction, therefore entering the lytic cycle, and release of new phages.. For example, UV lyses cells and these bacteria are known as lysogenic.
Lambda is a d-s DNA phage, that has a tail that doesn’t contract, and an icosahedral head. Its genome is linear, complimentary base pairs, with 2 cohesive ends. When lambda enters the host ligase connects the cohesive ends and makes the genome a circle. Lambda is a prophage.
During the lytic cycle, ligase is transforming the genome into a circle. Also, regulatory genes are the first to become transcribed because they control the lytic cycle. Transcription occurs either clockwise for counter clockwise.
For lysogeny to occur and not the lytic cycle, lambda needs a repressor. Lambda binds to the operator to block RNA polymerase activity. RNA synthesis of lambda doesn’t happen. The Cro protein binds to the operator, which tries to turn off transcription of the repressor gene.
In order for lysogeny to occur higher levels of Cro are needed. The lambda DNA can then insert itself inside the genome. The insertion enzyme is intergrase, and has a particular attachment site. The attachment sites are the gal and biotin operons. Lambda is a prophage.
Eukaryotic virus are characterized by morphology, DNA, or RNA, and how they are related genetically.
Eukaryotic viruses penetrate with fusion of cell membrane receptors (or envelope), releasing its nucleic acids, and removing its capsid.
In early genes the virus takes on host, and early mRNA is transcribed. Then viral DNA or RNA is made.
The late genes make capsid proteins, by self assembly. DNA can then enter.
Specific eukaryotic viruses are classified in 4 groups, and is based on replication and transcription relation to the host genome. For example, poliovirus
Sunday, February 21, 2010
Dictyostelium development and the relationship with temperature
I. Introduction
The group Mycetozoa, classified as an protozoa, includes the slime mold Dictyostelium and under certain conditions this amoebae is a useful organism that can be observed in multiple stages of development. It can develop form spores, to mature fruiting bodies that again release spores, and start the life cycle again. When the spores hatch they are called myxamoebae. Myxamoebae are eukaryotic cells, and while they feed, and mate the amoebae starts to aggregate. Aggregation is a starvation period that can last up to eight hours. During this stage of development cAMP receptors are made, phosphodiesterase inhibitors are formed, and a chemical signal is released (Gilbert, 2003). The amoebae is now shaped similar to a flatten nerve body with dendrites. The ameobiod is able to increase the cAMP gradient because of the signal and develop into the next stage of development. The amoebae next stage of development is now called a pseudoplasmodium. The pseudoplasmodium is slug like and can only move in one direction. While the slug is slinking along the agar dish, it eventually starts to settle on the posterior end, which are full of prespore cells. This stage is called transformation, but it is also nicknamed after the amoebae’s shape, a Mexican hat. During this stage of development the slime mold cells reorganize, and a tube on the top of the hat appears and secretes cellulose. Then, the prespore cells in the fruiting body migrate to the anterior, and prestalk cells migrate to the posterior and die at the fruiting body. The migration process of the two cell types takes up to ten hours to produce a mature fruiting body with a fruiting body mass, stalk, and spore mass (Gilbert, 2003). The Dictyostelium observed in the experiment were gorgeous under the microscope, and resembled a delicate tulip, with a very skinny stem, and a tightly wrapped bud. The spore mass on the anterior of the mature slime mold were now ready to release the spores and the development cycle will repeat itself.
The hypothesis of the experiment is Dictyostelium development will flourish at 37 degrees Celsius in an agar dish, rich of E. coli, and the slime mold with develop much slower at room temperature in an agar dish treated with E. coli.
II. General Procedures
The experiment was designed to test the life cycle of Dictyostelium under two different controlled temperatures and to observe how it influenced developmental stages.
In the experiment, approximately 8 pseudoplasmodium were identified and verified using a microscope. Then, the slugs where transplanted into two other Petri dishes. In the experiment a sterile loop was used, lightly passing the slime mold in a brush like motion onto the two separate Petri dishes that were labeled with initials, and temperatures. The Petri dishes both contained a nutrient agar, E. coli, and were carefully opened to prevent contamination, and to only opened to replant the slugs. Finally, one dish was placed in a controlled area at room temperature and the other dish was placed in a controlled area at 37 degrees Celsius. The Dictyostelium was observed eight times during a period of 12 school days.
III. Observations & Results
See attached observation log and drawings for addition experimental data.
IV. Discussion
The results of the experiment showed one prediction of the hypothesis was true, but the data also showed the second prediction was incorrect. The Dictyostelium that were placed in 37 degrees Celsius were observed in all stages of development, including spores, and myxamoebae. At 37 degrees Celsius the amoebae were also observed during aggregation, as a pseudoplasmodium, Mexican hat shape, in culmination, and as mature fruiting body. It appeared the slime molds were constantly developing spores and generating mature fruiting bodies and repeating the life cycle. The data concludes the cellular slime mold thrives in warm conditions, with E. coli. The life cycle in the 37 degree plate was continuous and repeating and the observations concluded that Dictyostelium enjoys hot, tropical conditions (like my grandparents), and would most likely be found in areas with this type of environment.
The pseudoplasmodium transferred into the room temperate Petri dish developed to a mature fruiting body with stalk and a spore mass. At first observation the mature fruiting bodies were in perfect condition, immobile, and resembled a pristine fossil secured in the agar. Twenty-four hours later, during the second observation the mature fruiting bodies were unchanged and the assumption is the Dictyostelium matured within the first twenty-fours hours and then died. The spore mass of the mature organism did not release spores for fertilization and the life cycle ended. The observation concluded Dictyostelium does not survive at room temperature, even though it was transferred into a nutrient agar plate with its favorite food, E. coli.
References:
Gilbert, S. F., (2003). Developmental Biology (7th ed.). Massachusetts: Sinauer Associates
Dictyostelium development and the relationship with temperature
The group Mycetozoa, classified as an protozoa, includes the slime mold Dictyostelium and under certain conditions this amoebae is a useful organism that can be observed in multiple stages of development. It can develop form spores, to mature fruiting bodies that again release spores, and start the life cycle again. When the spores hatch they are called myxamoebae. Myxamoebae are eukaryotic cells, and while they feed, and mate the amoebae starts to aggregate. Aggregation is a starvation period that can last up to eight hours. During this stage of development cAMP receptors are made, phosphodiesterase inhibitors are formed, and a chemical signal is released (Gilbert, 2003). The amoebae is now shaped similar to a flatten nerve body with dendrites. The ameobiod is able to increase the cAMP gradient because of the signal and develop into the next stage of development. The amoebae next stage of development is now called a pseudoplasmodium. The pseudoplasmodium is slug like and can only move in one direction. While the slug is slinking along the agar dish, it eventually starts to settle on the posterior end, which are full of prespore cells. This stage is called transformation, but it is also nicknamed after the amoebae’s shape, a Mexican hat. During this stage of development the slime mold cells reorganize, and a tube on the top of the hat appears and secretes cellulose. Then, the prespore cells in the fruiting body migrate to the anterior, and prestalk cells migrate to the posterior and die at the fruiting body. The migration process of the two cell types takes up to ten hours to produce a mature fruiting body with a fruiting body mass, stalk, and spore mass (Gilbert, 2003). The Dictyostelium observed in the experiment were gorgeous under the microscope, and resembled a delicate tulip, with a very skinny stem, and a tightly wrapped bud. The spore mass on the anterior of the mature slime mold were now ready to release the spores and the development cycle will repeat itself.
The hypothesis of the experiment is Dictyostelium development will flourish at 37 degrees Celsius in an agar dish, rich of E. coli, and the slime mold with develop much slower at room temperature in an agar dish treated with E. coli.
II. General Procedures
The experiment was designed to test the life cycle of Dictyostelium under two different controlled temperatures and to observe how it influenced developmental stages.
In the experiment, approximately 8 pseudoplasmodium were identified and verified using a microscope. Then, the slugs where transplanted into two other Petri dishes. In the experiment a sterile loop was used, lightly passing the slime mold in a brush like motion onto the two separate Petri dishes that were labeled with initials, and temperatures. The Petri dishes both contained a nutrient agar, E. coli, and were carefully opened to prevent contamination, and to only opened to replant the slugs. Finally, one dish was placed in a controlled area at room temperature and the other dish was placed in a controlled area at 37 degrees Celsius. The Dictyostelium was observed eight times during a period of 12 school days.
III. Observations & Results
See attached observation log and drawings for addition experimental data.
IV. Discussion
The results of the experiment showed one prediction of the hypothesis was true, but the data also showed the second prediction was incorrect. The Dictyostelium that were placed in 37 degrees Celsius were observed in all stages of development, including spores, and myxamoebae. At 37 degrees Celsius the amoebae were also observed during aggregation, as a pseudoplasmodium, Mexican hat shape, in culmination, and as mature fruiting body. It appeared the slime molds were constantly developing spores and generating mature fruiting bodies and repeating the life cycle. The data concludes the cellular slime mold thrives in warm conditions, with E. coli. The life cycle in the 37 degree plate was continuous and repeating and the observations concluded that Dictyostelium enjoys hot, tropical conditions (like my grandparents), and would most likely be found in areas with this type of environment.
The pseudoplasmodium transferred into the room temperate Petri dish developed to a mature fruiting body with stalk and a spore mass. At first observation the mature fruiting bodies were in perfect condition, immobile, and resembled a pristine fossil secured in the agar. Twenty-four hours later, during the second observation the mature fruiting bodies were unchanged and the assumption is the Dictyostelium matured within the first twenty-fours hours and then died. The spore mass of the mature organism did not release spores for fertilization and the life cycle ended. The observation concluded Dictyostelium does not survive at room temperature, even though it was transferred into a nutrient agar plate with its favorite food, E. coli.
References:
Gilbert, S. F., (2003). Developmental Biology (7th ed.). Massachusetts: Sinauer Associates
Dictyostelium development and the relationship with temperature
Saturday, November 21, 2009
Chem Exam 3
What is meant by the term electromagnetic radiation and what are its (physical) properties?
Waves and light are considered electromagnetic radiations. Electromagnetic radiations physical properties are dependant on wavelengths and frequencies. This is known as the electromagnetic spectrum. It includes gamma rays, x rays, far ultra-violet, near ultra violet, visible, near infrared, far infrared, microwaves, radio waves, and radar.
A wave is constituted by its frequency and wavelength. Wave length is represented by lambda. Lambda is the exactly the distance between to points, or peaks on the wave.
Wavelength is calculated using nanometers. (1 nm = 10-9 m) See example, 7.2 pg. 267--Heather, this is why you use 10-9!
Frequency is how many times a wave passes a point during a second. See figure 7.4 for a simple explanation of wave length and frequency, and to see how they relate.
Important Calculation:
When asked to calculate wavelength use below formula:
Lambda (distance)=c (speed of light constant 3.00 x 108 m/s)/v (frequency)
When asked to calculate frequency use below formula:
V (frequency)=c (speed of light constant)/lambda (distance)
Our desire is to learn something more about the atom and atomic structure. In chapter 2 we learned about Dalton's Atomic Theory (the atomic nature of matter). The nuclear theory of the atom had us to understand that the atom has a compact nucleus and is largely empty space containing the electrons outside of the nucleus. Describe what is happening in figures 7.1 and 7.2. What kind(s) of information are figures 7.1 and 7.2 providing? What kind(s) of information are figures 7.3-7.5 providing? In figure 7.4 the top wave has a frequency of 2 Hertz. What does that mean and how would I be able to determine that from the figure?
Further study: problems 7.35-7.38
In figure 7.1 a “wire loop” is placed into a flame. Depending on the placement of the wire loop the light emitted from the flame is different. In the first picture the loop is placed horizontal and close to the gas apparatus. The metal element releases the atoms in gas form and show the element and its particular color. For example, the first picture in 7.1 is lithium, which produced a red color, and a blue color for the gas. In the second picture, the wire loop was moved vertically and higher up, producing a yellow color, and again a blue color from the gas. Yellow emission of atoms is an indication of the element Na, sodium. In figure 7.2 each element is placed onto a chart, showing the color that corresponded to the visible light emitted by the elements atoms. The wavelength is also determined for each element and its numerical characteristics in nanometers.
In figure 7.3 the illustration is of a water wave ripple. This figure shows Lambda (wavelength), with identical peaks of the ripples, exactly the same space from each other.
In figured 7.4 the relationship between frequency and wavelength are correlated. See first discussion post for a more detailed explanation. You can determine the top wavelength in figure 7.4 as 2 Hz because of the two equal peaks frequency. The bottom example have 4 identical peaks in one second, giving it a frequency of 4 Hz.
Practice Problem 7.35
Since the question is asking for wavelength use this equation Lambda (distance)=c (speed of light constant 3.00 x 108 m/s)/v (frequency)
3.00x108 m/s/1.365 x106/s = 219.6 m (because seconds cancel)
Practice Problem 7.37
V (frequency)=c (speed of light constant)/lambda (distance)
V=3.00x108 m/s/478x 10-9= 6.27 x 1014/s
Problem 1
The Black Body Problem was an experiment Max Planck did. He heated solids and watched them change color as the temperature was increased and decreased. For example, at 750 degrees Celsius a solid metal object glows red, and at 1200 degrees Celsius a metal solid glows white. I think this concept of heating solids to observe a color is known as blackbody radiation.
Planck’s experiment created a theory that the atoms in a solid vibrate, and only have a particular vibration (E).
Equation:
E=nhv
E(atom vibration)=n(quantum number, or size)h(Planck’s constant – 6.63 x 10-37)v(frequency)
In the attached figure, another theory (Rayleigh-Jeans Law) is when a solid is experimented with at low temperatures. The wavelength doesn’t pass the horizontal axis, which means it slows down, and is not visible. There is no vibration.
Problem 2
Photoelectric effect is a theory from Einstein. He used Planck’s data about quantum theory and expanded on it. Einstein theorized that light (from any source) is made up of photons, and the photons eject electrons from objects (metals) it hits. In order to see a color the amount of electrons ejected need to be over a certain number, also known as “threshold value.”
Light behaves like matter because of the electromagnetic energy (photon) in the light. When photons hit an object the energy is absorbed in the object, and the photon is gone. Einstein’s equation shows the relationship.
Equation:
E=hv
E(vibration)=h(Planck’s constant – 6.63 x 10-37)v(frequency)
In figure 7.6 electromagnetic energy or photons, are being shined on a mental object. The metal object is ejecting the electrons and they are being caught by the positive wire connected to the metal. This is causing the ammeter in the battery to move because of the capturing of the ejected electrons from the photons (or photoelectric energy).
An energy of 2.0 x 102 kJ/mol is required to cause a cesium atom on a metal surface to lose an electron. What is the quanta of energy per atom? Calculate the longest possible wavelength of light that can ionize a cesium atom. In what region of the electromagnetic spectrum is this radiation found?
Problem one
Since the equation is E=hv, I think you can change the equation to get quanta into v=E/n
2.0 x 102 / 6.63 x 10-35 = 3.02 x 1036 (not sure what units)
Longest possible wavelength
This is the longest as possible, because the speed of light is constant (?).
Radio Waves (?)
Heather –
Did you get this?
You are an engineer designing a switch that works by the photoelectric effect. The metal you wish to use in your device requires 6.7 x 10-19 J/atom to remove an electron. Will the switch work if the light falling on the metal has a wavelength of 540 nm or greater? Why or why not?
No the switch will NOT work if the lights wavelength is 540 nm. The quanta frequency would need to be more than double.
Why because of Mathematical Explanation:
Lambda=3.00 x 108 / 540 x 10-9 = 5.56 x 1014
E= (6.63 x 10-34)(5.56 x 1014) = 3.69 x10-19 (required 6.7 x 10-19 J/atom)
Problem 7.49
WOW I think I got this!
(-RH/25)-(-RH/9)=-9RH+25RH/225=16RH/225=hv
v=16RH/225h=16/225(2.179x10-18)/(6.626x10-34)=2.34 x 1014
Problem 7.50
Am I right?
(-RH/16)-(-RH/9)=-9RH+16RH/144=7RH/144=hv
v=7RH/144h=7/144(2.179x10-18)/(6.626x10-34)=1.60 x 1014
Problem 7.51
I know this is right!!!
(-RH/4)-(-RH/1)=-1RH+4RH/4=3RH/4=hv
v=3RH/4h=3/4(2.179x10-18)/(6.626x10-34)=1.21 x 10-7 or 121 nm, Near Ultra Violet
Problem 7.52
Is this right?
(-RH/25)-(-RH/16)=-16RH+25RH/400=9RH/400=hv
v=9RH/400h=9/400(2.179x10-18)/(6.626x10-34)= 7.40 x 1013, Near Infrared
I do not understand what you are looking for***Using figure 7.11 and Example 7.4, assign these bands to electron transitions within the hydrogen atom****
Exercise 7.5
I need help with this. I don’t understand
Part A. de Broglie Relation
Exercise 7.6
6.63 x 10-34/2.19 x 106 = 3.03 x 10-40 or 303 pm (??)
Problems 7.57
WOW! I am getting good!
Use the equation lambda=h/mv, where v is now speed because the question is asking the wavelength of a neutron.
6.63 x 10-34/1.67 x 10-27 (4.15) = 9.57 pm
Problem 7.58
6.63 x 10-34/1.67 x 10-27 (6.58) = 6.03 10-8, far ultra-violet
Part B. Matter-waves, the uncertainty principle and the Wave Model of the Atom
Problem 7.61 (pg. 290)
6.63 x 10-34/(145)(30.0) = 1.52 x 10-37 ( the answer is 1.52 x 10-22 --any idea what went wrong), decreased, smaller
The uncertainty value is since the electron is affected by the nucleus, in moves around inside a shell. For example, how earth goes around the sun. Even though the electron has an as exact orbit in an atom around the nucleus (or shell), the unknown of where how the electron will move is unknown value.
In figure 7.17 mostly you will find the hydrogen atoms electron in this region (pg.279). It is somewhere from 110 pm, and below from the lowest energy from only the wave.
In figure 7.18 the radius is shown of the probability of where the hydrogen atoms electron is from the nucleus. The peak in the figure is at 50 pm, which in the highest radial probability.
Part C. Wave Model Versus Bohr's Model
In think figure 7.10 is confusing. I do understand how the negative constant (-RH) is related to principal quantum number (n). As the n increase the -RH increases? Does anyone know why? The graph doesn’t show the spherical shape of the atom, instead it shows it in a straight line and maybe that’s why I do not like it.
In figure for 7.23 it is showing a 1s orbital. The electron distribution, or probability of finding the electrons is where the pink color is darker. In the 2s orbital the probability has two dark pink rings. Again, that denotes where the electron should be. In figure 7.24 shows the outer membrane (not sure what to call that) of the atom is least likely place you will find the electron. Since the diagram is a cutaway, you can see the darkest pink rings and that is where you will most likely find the electron.
If I was to redraw the Bohr I would use triangles. Each line would represent one n value. n=1 being the smallest triangle, n=2 second triangle, n=3 third triangle
The Pauli Exclusion principle is that no two elements can have the same n number. For example each shell holds two electrons. One 1s orbital holds two electrons, one ms value is ½ the magnetic spin and the other ms value is – ½ the magnetic spin. The spin is represented in arrows. You can not have two up arrows in an orbit because of the electrons behavior to magnetic energy.
Exercise 8.1
A. Impossible, because 1s can hold 2 electrons.
B. Impossible, you have to fill up 1s first, then 2s second, the 2p
C. Impossible, two with the same spin
D. Possible, written correctly
E. Impossible, 2s can only fit 2 electrons
F. Impossible, after the 3p orbital is full, you have to put one electron in the 4s orbital to move on to the next orbital
Exercise 8.41
A. Impossible, two same spin
B. Possible, ok
C. Impossible, two same spin
D. Impossible, three electrons in one orbit (2 max)
Exercise 8.42
A. Impossible, two same spin
B. Possible, ok
C. Impossible, three electrons in one orbit
D. Possible,
Exercise 8.43
A. Impossible, 1s isn’t full
B. Impossible, 3s only room for two electrons
C. Possible, ok
D. Possible, d can hold 10
Hund's rule is that you must fill each subshell with a positive ms value. This is because they have low energy and have to be placed into different orbital subshells.
An example of an orbital diagram that obeys the rule is one page 309. [Ar] electron configuration (valance shell) is 1s22p63s63p6. If you use the Hund’s rule you can abbreviate [Ar] 3d64s2 . This is because according to the rule, you can fill up each orbital with one electron (in the same spin). Instead of pairing on the electrons in the orbital, they can be separated out.
The Aufbau principle is the building of the ground state of the electron configuration by filling the orbitals in its electron configuration. For example, 3s has lower energy than 3p. The longer the electron configuration the higher the energy it will be (build up principle). Another example is 2p2 has less energy than 2p6.
On pg 309 Neon obeys the rules, and C and N does not. (I think)
C & N= Paramagnetic Neon = Diamagnetic (definitely)
Other
An orbital that has two electrons is more stable than an orbital that has one electron.
Waves and light are considered electromagnetic radiations. Electromagnetic radiations physical properties are dependant on wavelengths and frequencies. This is known as the electromagnetic spectrum. It includes gamma rays, x rays, far ultra-violet, near ultra violet, visible, near infrared, far infrared, microwaves, radio waves, and radar.
A wave is constituted by its frequency and wavelength. Wave length is represented by lambda. Lambda is the exactly the distance between to points, or peaks on the wave.
Wavelength is calculated using nanometers. (1 nm = 10-9 m) See example, 7.2 pg. 267--Heather, this is why you use 10-9!
Frequency is how many times a wave passes a point during a second. See figure 7.4 for a simple explanation of wave length and frequency, and to see how they relate.
Important Calculation:
When asked to calculate wavelength use below formula:
Lambda (distance)=c (speed of light constant 3.00 x 108 m/s)/v (frequency)
When asked to calculate frequency use below formula:
V (frequency)=c (speed of light constant)/lambda (distance)
Our desire is to learn something more about the atom and atomic structure. In chapter 2 we learned about Dalton's Atomic Theory (the atomic nature of matter). The nuclear theory of the atom had us to understand that the atom has a compact nucleus and is largely empty space containing the electrons outside of the nucleus. Describe what is happening in figures 7.1 and 7.2. What kind(s) of information are figures 7.1 and 7.2 providing? What kind(s) of information are figures 7.3-7.5 providing? In figure 7.4 the top wave has a frequency of 2 Hertz. What does that mean and how would I be able to determine that from the figure?
Further study: problems 7.35-7.38
In figure 7.1 a “wire loop” is placed into a flame. Depending on the placement of the wire loop the light emitted from the flame is different. In the first picture the loop is placed horizontal and close to the gas apparatus. The metal element releases the atoms in gas form and show the element and its particular color. For example, the first picture in 7.1 is lithium, which produced a red color, and a blue color for the gas. In the second picture, the wire loop was moved vertically and higher up, producing a yellow color, and again a blue color from the gas. Yellow emission of atoms is an indication of the element Na, sodium. In figure 7.2 each element is placed onto a chart, showing the color that corresponded to the visible light emitted by the elements atoms. The wavelength is also determined for each element and its numerical characteristics in nanometers.
In figure 7.3 the illustration is of a water wave ripple. This figure shows Lambda (wavelength), with identical peaks of the ripples, exactly the same space from each other.
In figured 7.4 the relationship between frequency and wavelength are correlated. See first discussion post for a more detailed explanation. You can determine the top wavelength in figure 7.4 as 2 Hz because of the two equal peaks frequency. The bottom example have 4 identical peaks in one second, giving it a frequency of 4 Hz.
Practice Problem 7.35
Since the question is asking for wavelength use this equation Lambda (distance)=c (speed of light constant 3.00 x 108 m/s)/v (frequency)
3.00x108 m/s/1.365 x106/s = 219.6 m (because seconds cancel)
Practice Problem 7.37
V (frequency)=c (speed of light constant)/lambda (distance)
V=3.00x108 m/s/478x 10-9= 6.27 x 1014/s
Problem 1
The Black Body Problem was an experiment Max Planck did. He heated solids and watched them change color as the temperature was increased and decreased. For example, at 750 degrees Celsius a solid metal object glows red, and at 1200 degrees Celsius a metal solid glows white. I think this concept of heating solids to observe a color is known as blackbody radiation.
Planck’s experiment created a theory that the atoms in a solid vibrate, and only have a particular vibration (E).
Equation:
E=nhv
E(atom vibration)=n(quantum number, or size)h(Planck’s constant – 6.63 x 10-37)v(frequency)
In the attached figure, another theory (Rayleigh-Jeans Law) is when a solid is experimented with at low temperatures. The wavelength doesn’t pass the horizontal axis, which means it slows down, and is not visible. There is no vibration.
Problem 2
Photoelectric effect is a theory from Einstein. He used Planck’s data about quantum theory and expanded on it. Einstein theorized that light (from any source) is made up of photons, and the photons eject electrons from objects (metals) it hits. In order to see a color the amount of electrons ejected need to be over a certain number, also known as “threshold value.”
Light behaves like matter because of the electromagnetic energy (photon) in the light. When photons hit an object the energy is absorbed in the object, and the photon is gone. Einstein’s equation shows the relationship.
Equation:
E=hv
E(vibration)=h(Planck’s constant – 6.63 x 10-37)v(frequency)
In figure 7.6 electromagnetic energy or photons, are being shined on a mental object. The metal object is ejecting the electrons and they are being caught by the positive wire connected to the metal. This is causing the ammeter in the battery to move because of the capturing of the ejected electrons from the photons (or photoelectric energy).
An energy of 2.0 x 102 kJ/mol is required to cause a cesium atom on a metal surface to lose an electron. What is the quanta of energy per atom? Calculate the longest possible wavelength of light that can ionize a cesium atom. In what region of the electromagnetic spectrum is this radiation found?
Problem one
Since the equation is E=hv, I think you can change the equation to get quanta into v=E/n
2.0 x 102 / 6.63 x 10-35 = 3.02 x 1036 (not sure what units)
Longest possible wavelength
This is the longest as possible, because the speed of light is constant (?).
Radio Waves (?)
Heather –
Did you get this?
You are an engineer designing a switch that works by the photoelectric effect. The metal you wish to use in your device requires 6.7 x 10-19 J/atom to remove an electron. Will the switch work if the light falling on the metal has a wavelength of 540 nm or greater? Why or why not?
No the switch will NOT work if the lights wavelength is 540 nm. The quanta frequency would need to be more than double.
Why because of Mathematical Explanation:
Lambda=3.00 x 108 / 540 x 10-9 = 5.56 x 1014
E= (6.63 x 10-34)(5.56 x 1014) = 3.69 x10-19 (required 6.7 x 10-19 J/atom)
Problem 7.49
WOW I think I got this!
(-RH/25)-(-RH/9)=-9RH+25RH/225=16RH/225=hv
v=16RH/225h=16/225(2.179x10-18)/(6.626x10-34)=2.34 x 1014
Problem 7.50
Am I right?
(-RH/16)-(-RH/9)=-9RH+16RH/144=7RH/144=hv
v=7RH/144h=7/144(2.179x10-18)/(6.626x10-34)=1.60 x 1014
Problem 7.51
I know this is right!!!
(-RH/4)-(-RH/1)=-1RH+4RH/4=3RH/4=hv
v=3RH/4h=3/4(2.179x10-18)/(6.626x10-34)=1.21 x 10-7 or 121 nm, Near Ultra Violet
Problem 7.52
Is this right?
(-RH/25)-(-RH/16)=-16RH+25RH/400=9RH/400=hv
v=9RH/400h=9/400(2.179x10-18)/(6.626x10-34)= 7.40 x 1013, Near Infrared
I do not understand what you are looking for***Using figure 7.11 and Example 7.4, assign these bands to electron transitions within the hydrogen atom****
Exercise 7.5
I need help with this. I don’t understand
Part A. de Broglie Relation
Exercise 7.6
6.63 x 10-34/2.19 x 106 = 3.03 x 10-40 or 303 pm (??)
Problems 7.57
WOW! I am getting good!
Use the equation lambda=h/mv, where v is now speed because the question is asking the wavelength of a neutron.
6.63 x 10-34/1.67 x 10-27 (4.15) = 9.57 pm
Problem 7.58
6.63 x 10-34/1.67 x 10-27 (6.58) = 6.03 10-8, far ultra-violet
Part B. Matter-waves, the uncertainty principle and the Wave Model of the Atom
Problem 7.61 (pg. 290)
6.63 x 10-34/(145)(30.0) = 1.52 x 10-37 ( the answer is 1.52 x 10-22 --any idea what went wrong), decreased, smaller
The uncertainty value is since the electron is affected by the nucleus, in moves around inside a shell. For example, how earth goes around the sun. Even though the electron has an as exact orbit in an atom around the nucleus (or shell), the unknown of where how the electron will move is unknown value.
In figure 7.17 mostly you will find the hydrogen atoms electron in this region (pg.279). It is somewhere from 110 pm, and below from the lowest energy from only the wave.
In figure 7.18 the radius is shown of the probability of where the hydrogen atoms electron is from the nucleus. The peak in the figure is at 50 pm, which in the highest radial probability.
Part C. Wave Model Versus Bohr's Model
In think figure 7.10 is confusing. I do understand how the negative constant (-RH) is related to principal quantum number (n). As the n increase the -RH increases? Does anyone know why? The graph doesn’t show the spherical shape of the atom, instead it shows it in a straight line and maybe that’s why I do not like it.
In figure for 7.23 it is showing a 1s orbital. The electron distribution, or probability of finding the electrons is where the pink color is darker. In the 2s orbital the probability has two dark pink rings. Again, that denotes where the electron should be. In figure 7.24 shows the outer membrane (not sure what to call that) of the atom is least likely place you will find the electron. Since the diagram is a cutaway, you can see the darkest pink rings and that is where you will most likely find the electron.
If I was to redraw the Bohr I would use triangles. Each line would represent one n value. n=1 being the smallest triangle, n=2 second triangle, n=3 third triangle
The Pauli Exclusion principle is that no two elements can have the same n number. For example each shell holds two electrons. One 1s orbital holds two electrons, one ms value is ½ the magnetic spin and the other ms value is – ½ the magnetic spin. The spin is represented in arrows. You can not have two up arrows in an orbit because of the electrons behavior to magnetic energy.
Exercise 8.1
A. Impossible, because 1s can hold 2 electrons.
B. Impossible, you have to fill up 1s first, then 2s second, the 2p
C. Impossible, two with the same spin
D. Possible, written correctly
E. Impossible, 2s can only fit 2 electrons
F. Impossible, after the 3p orbital is full, you have to put one electron in the 4s orbital to move on to the next orbital
Exercise 8.41
A. Impossible, two same spin
B. Possible, ok
C. Impossible, two same spin
D. Impossible, three electrons in one orbit (2 max)
Exercise 8.42
A. Impossible, two same spin
B. Possible, ok
C. Impossible, three electrons in one orbit
D. Possible,
Exercise 8.43
A. Impossible, 1s isn’t full
B. Impossible, 3s only room for two electrons
C. Possible, ok
D. Possible, d can hold 10
Hund's rule is that you must fill each subshell with a positive ms value. This is because they have low energy and have to be placed into different orbital subshells.
An example of an orbital diagram that obeys the rule is one page 309. [Ar] electron configuration (valance shell) is 1s22p63s63p6. If you use the Hund’s rule you can abbreviate [Ar] 3d64s2 . This is because according to the rule, you can fill up each orbital with one electron (in the same spin). Instead of pairing on the electrons in the orbital, they can be separated out.
The Aufbau principle is the building of the ground state of the electron configuration by filling the orbitals in its electron configuration. For example, 3s has lower energy than 3p. The longer the electron configuration the higher the energy it will be (build up principle). Another example is 2p2 has less energy than 2p6.
On pg 309 Neon obeys the rules, and C and N does not. (I think)
C & N= Paramagnetic Neon = Diamagnetic (definitely)
Other
An orbital that has two electrons is more stable than an orbital that has one electron.
Wednesday, October 21, 2009
Benzene (C6H6) burns in air to produce carbon dioxide and liquid water. What is the heat released when 49.04 grams of benzene is combusted?
Benzene (C6H6) burns in air to produce carbon dioxide and liquid water. What is the heat released when 49.04 grams of benzene is combusted? The standard enthalpy of formation of benzene is 49.04 kJ/mol
-3268 kJ 1000 J 1 ev 1 amu 1.66054 x 10-27 1000 g
mol 1 kJ 1.60218 x 10-19 J 931.5 x 106 J 1 amu 1 kJ
= -1.14 x 10-28 grams
-3268 kJ 1000 J 1 ev 1 amu 1.66054 x 10-27 1000 g
mol 1 kJ 1.60218 x 10-19 J 931.5 x 106 J 1 amu 1 kJ
= -1.14 x 10-28 grams
Sunday, October 11, 2009
C A Vocab
Oviparous- animals are animals that lay eggs, with little or no other embryonic development within the mother
Viviparous- producing living young instead of eggs from within the body in the manner of nearly all mammals, many reptiles, and a few fishes
Ovoviviparous- producing eggs that develop within the maternal body and hatch within or immediately after extrusion from the parent
Ontogeny – changes in organism from zygote to death, although often focused on events from zygote to maturity.
Cleavage – a rapid series of cell divisions that follows fertilization and produces a multi-cellular blastula.
Blastocoel- the cavity of a blastula
Neurulation- an early vertebrate embryo which follows the gastrula and in which nervous tissue begins to differentiate and the basic pattern of the vertebrate begins to emerge
Trophoblast- the outer cellular layer of the mammalian blastocyst
Inner cell mass- the portion of the blastocyst of a mammalian embryo that is destined to become the embryo proper
Blastocyst- the mammalian blastula
Neural crest cells- migrate and ultimately differentiate into a wide variety of adult structures. The migrations begin cranially and gradually extend caudally. They are determined by both intrinsic properties of the neural crest cells and the features of the external environment encountered by the migrating cells - extracellular matrices and substrates.
Gastrula- an early metazoan embryo in which the ectoderm, mesoderm, and endoderm are established either by invagination of the blastula (as in fish and amphibians) to form a multilayered cellular cup with a blastopore opening into the archenteron or (as in reptiles, birds, and mammals) by differentiation of the upper layer of the blastodisc into the ectoderm and the lower layer into the endoderm and by the inward migration of cells through the primitive streak to form the mesoderm
Gastrocoele- ? rib-shaped dermal bones located in the abdominal region
Archenteron- the cavity of the gastrula of an embryo forming a primitive gut—called also gastrocoel
Chorion- the highly vascular outer embryonic membrane that is associated with the allantois in the formation of the placenta
Somites- ?
Allantois- a vascular fetal membrane of reptiles, birds, or mammals that is formed as a pouch from the hindgut and that in placental mammals is intimately associated with the chorion in formation of the placenta
Yolk Sac- a membranous sac of most vertebrates that is attached to an embryo and encloses the yolk, that is continuous in most forms including humans through the omphalomesenteric duct with the intestinal cavity of the embryo, that is abundantly supplied with blood vessels which transport nutritive yolk products to the developing embryo, and that in placental mammals is nearly vestigial and functions chiefly prior to the formation of the placenta
Blastopore- the opening into the primitive gut formed at gastrulation
Amnion- a saclike membrance that holds the develipoing embryo in a compartment of water
Coelom- the fluid filled body cavity formed within the mesoderm
transverse septum-
cleidoic egg- enclosed in a relatively impervious shell which reduces free exchange with the environment
Diaphragm- a body partition of muscle and connective tissue ; specifically : the partition separating the chest and abdominal cavities in mammals
Organogenesis- the origin and development of bodily organs
Holoblastic cleavage – early mitotic planes pass entirely through the cleaving embryo
Discoidal cleavage – early mitotic divisions restricted to the animal pole
Meroblastic- characterized by or being incomplete cleavage as a result of the presence of an impeding mass of yolk material (as in the eggs of birds)
Microlecithal- pertaining to eggs that contain small quantities of stored yolk
Mesolecithal- ?
Macrolecithal- ?
Epidermis – the skin layer over the dermis that is derived from ectoderm
Example: outer layer of the skin, composed of stratified squamous epithelium
Dermis - inner mesodermic layer of the skin, vascular
Example:
Sebaceous glands- any of the small sacculated glands lodged in the substance of the derma, usually opening into the hair follicles, and secreting an oily or greasy material composed in great part of fat which softens and lubricates the hair and skin
Sweat glands- a simple tubular gland of the skin that secretes perspiration, in humans is widely distributed in nearly all parts of the skin, and consists typically of an epithelial tube extending spirally from a minute pore on the surface of the skin into the dermis or subcutaneous tissues where it ends in a convoluted tuft
mammary- a simple tubular gland of the skin that secretes perspiration, in humans is widely distributed in nearly all parts of the skin, and consists typically of an epithelial tube extending spirally from a minute pore on the surface of the skin into the dermis or subcutaneous tissues where it ends in a convoluted tuft
hair - a slender threadlike outgrowth of the epidermis of an anima
nails- are made of keratin
Melanocytes - an epidermal cell that produces melanin
keratin –
Example: hair and nails
squamous epithelium- scale-like cells
stratum basale feathers –
claws-
Chromatophores- a pigment-bearing cell
Example: higher levels darker skin, lower levels whiter skin
Photophores- light-emitting organ which appears as luminous spots on various marine animals, including fish and cephalopods
Example: Firefly Squid, Pachystomias
Ectotherm- a cold-blooded animal
Endotherm- a warm-blooded animal
Poikilotherm- an organism (as a frog) with a variable body temperature that is usually slightly higher than the temperature of its environment : a cold-blooded organism—called also heterotherm
Horns-
Epidermal scales – scales are tough, shed
Example: reptiles, and exposed skin in birds
Ctenoid scales- toothed outer edge, and are usually found on more bony fish
Example: spiny fin rays, bass and the angel fish
Placoid scales- are found on cartilaginous fish
Example: sharks
Cycloid scales-
Example: flatfishes (flounders, fluke, soles)
Mucus glands-
Axial Skeleton - the skeleton of the trunk and head
appendicular skeleton- consists of the girdles and the skeleton of the limb
Neurocranium- the portion of the skull that encloses and protects the brain
Splanchnocranium- the portion of the skull that arises from the first three branchial arches and forms the supporting structure of the jaws
Dermatocranium- Bony parts of the skull derived from ossifications in the dermis of the skin
Hyaline cartilage- cartilage consisting of cells embedded in an apparently homogeneous matrix, present in joints and respiratory passages, and forming most of the fetal skeleton
Calcified cartilage- flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle
Fibrocartilage- cartilage in which the matrix except immediately about the cells is largely composed of fibers like those of ordinary connective tissue
Diaphysis- the shaft of a long bone
Epiphyses- an end of a long bone
Metaphysic- the transitional zone at which the diaphysis and epiphysis of a bone come together
Endochondral bone -relating to, formed by, or being ossification that takes place from centers arising in cartilage and involves deposition of lime salts in the cartilage matrix followed by secondary absorption and replacement by true bony tissue
membrane bone- a bone that ossifies directly in connective tissue without previous existence as cartilage
heterotopic bone- the percentage of osteoblasts is typically double that of normal bone
Example: formation of bone where it is not normally found, as in muscle
Blastema- a mass of living substance capable of growth and differentiation
Mesenchyme- loosely organized undifferentiated mesodermal cells that give rise to such structures as connective tissues, blood, lymphatics, bone, and cartilage
Chondrocytes- a cartilage cell
Chondroblast - a cell that produces cartilage
Osteocytes- a cell that is characteristic of adult bone and is isolated in a lacuna of the bone substance
osteoblast - a bone-forming cell
osteoclasts- bone cleaning cell
Compact bone - tightly packed tissue/bone
Spongy bone - tissue that makes up the interior of bones
Acellular bone- metabolically active tissue.
Example: Bone tissue in the Actinopterygii
Fontanels- a membrane-covered opening in bone or between bones
Example: any of the spaces closed by membranous structures between the uncompleted angles of the parietal bones and the neighboring bones of a fetal or young skull
Cranial kinesis- ??movement between the upper jaw and braincase
Cranial akinesis - ?skulls cannot perform the. actions of the kinetic skull
Sesamoid cartilages ?
Joints -
Sutures - a stitch used by doctors and surgeons to hold tissue together
Diarthrosis- a freely movable joint
Example: synovial joint
Synanthrosis- an immovable articulation in which the bones are united by intervening fibrous connective tissues
Amphiarthrosis- a slightly movable articulation
Synovial cartilaginous- stringy fluid found in the cavities of synovial joints
Fibrous joints- The fibrous joints are further divided into three types
Example: Sutures are found between bones of the skull. In fetal skulls the sutures are wide to allow slight movement during birth. They later become rigid synarthrodial
Hyostylic - mandibular arch attaches through the hyomandibula.
Craniostylic- incorporated into cranium, jaws (reduced to dentary alone) suspended directly from squamosal bone
Viviparous- producing living young instead of eggs from within the body in the manner of nearly all mammals, many reptiles, and a few fishes
Ovoviviparous- producing eggs that develop within the maternal body and hatch within or immediately after extrusion from the parent
Ontogeny – changes in organism from zygote to death, although often focused on events from zygote to maturity.
Cleavage – a rapid series of cell divisions that follows fertilization and produces a multi-cellular blastula.
Blastocoel- the cavity of a blastula
Neurulation- an early vertebrate embryo which follows the gastrula and in which nervous tissue begins to differentiate and the basic pattern of the vertebrate begins to emerge
Trophoblast- the outer cellular layer of the mammalian blastocyst
Inner cell mass- the portion of the blastocyst of a mammalian embryo that is destined to become the embryo proper
Blastocyst- the mammalian blastula
Neural crest cells- migrate and ultimately differentiate into a wide variety of adult structures. The migrations begin cranially and gradually extend caudally. They are determined by both intrinsic properties of the neural crest cells and the features of the external environment encountered by the migrating cells - extracellular matrices and substrates.
Gastrula- an early metazoan embryo in which the ectoderm, mesoderm, and endoderm are established either by invagination of the blastula (as in fish and amphibians) to form a multilayered cellular cup with a blastopore opening into the archenteron or (as in reptiles, birds, and mammals) by differentiation of the upper layer of the blastodisc into the ectoderm and the lower layer into the endoderm and by the inward migration of cells through the primitive streak to form the mesoderm
Gastrocoele- ? rib-shaped dermal bones located in the abdominal region
Archenteron- the cavity of the gastrula of an embryo forming a primitive gut—called also gastrocoel
Chorion- the highly vascular outer embryonic membrane that is associated with the allantois in the formation of the placenta
Somites- ?
Allantois- a vascular fetal membrane of reptiles, birds, or mammals that is formed as a pouch from the hindgut and that in placental mammals is intimately associated with the chorion in formation of the placenta
Yolk Sac- a membranous sac of most vertebrates that is attached to an embryo and encloses the yolk, that is continuous in most forms including humans through the omphalomesenteric duct with the intestinal cavity of the embryo, that is abundantly supplied with blood vessels which transport nutritive yolk products to the developing embryo, and that in placental mammals is nearly vestigial and functions chiefly prior to the formation of the placenta
Blastopore- the opening into the primitive gut formed at gastrulation
Amnion- a saclike membrance that holds the develipoing embryo in a compartment of water
Coelom- the fluid filled body cavity formed within the mesoderm
transverse septum-
cleidoic egg- enclosed in a relatively impervious shell which reduces free exchange with the environment
Diaphragm- a body partition of muscle and connective tissue ; specifically : the partition separating the chest and abdominal cavities in mammals
Organogenesis- the origin and development of bodily organs
Holoblastic cleavage – early mitotic planes pass entirely through the cleaving embryo
Discoidal cleavage – early mitotic divisions restricted to the animal pole
Meroblastic- characterized by or being incomplete cleavage as a result of the presence of an impeding mass of yolk material (as in the eggs of birds)
Microlecithal- pertaining to eggs that contain small quantities of stored yolk
Mesolecithal- ?
Macrolecithal- ?
Epidermis – the skin layer over the dermis that is derived from ectoderm
Example: outer layer of the skin, composed of stratified squamous epithelium
Dermis - inner mesodermic layer of the skin, vascular
Example:
Sebaceous glands- any of the small sacculated glands lodged in the substance of the derma, usually opening into the hair follicles, and secreting an oily or greasy material composed in great part of fat which softens and lubricates the hair and skin
Sweat glands- a simple tubular gland of the skin that secretes perspiration, in humans is widely distributed in nearly all parts of the skin, and consists typically of an epithelial tube extending spirally from a minute pore on the surface of the skin into the dermis or subcutaneous tissues where it ends in a convoluted tuft
mammary- a simple tubular gland of the skin that secretes perspiration, in humans is widely distributed in nearly all parts of the skin, and consists typically of an epithelial tube extending spirally from a minute pore on the surface of the skin into the dermis or subcutaneous tissues where it ends in a convoluted tuft
hair - a slender threadlike outgrowth of the epidermis of an anima
nails- are made of keratin
Melanocytes - an epidermal cell that produces melanin
keratin –
Example: hair and nails
squamous epithelium- scale-like cells
stratum basale feathers –
claws-
Chromatophores- a pigment-bearing cell
Example: higher levels darker skin, lower levels whiter skin
Photophores- light-emitting organ which appears as luminous spots on various marine animals, including fish and cephalopods
Example: Firefly Squid, Pachystomias
Ectotherm- a cold-blooded animal
Endotherm- a warm-blooded animal
Poikilotherm- an organism (as a frog) with a variable body temperature that is usually slightly higher than the temperature of its environment : a cold-blooded organism—called also heterotherm
Horns-
Epidermal scales – scales are tough, shed
Example: reptiles, and exposed skin in birds
Ctenoid scales- toothed outer edge, and are usually found on more bony fish
Example: spiny fin rays, bass and the angel fish
Placoid scales- are found on cartilaginous fish
Example: sharks
Cycloid scales-
Example: flatfishes (flounders, fluke, soles)
Mucus glands-
Axial Skeleton - the skeleton of the trunk and head
appendicular skeleton- consists of the girdles and the skeleton of the limb
Neurocranium- the portion of the skull that encloses and protects the brain
Splanchnocranium- the portion of the skull that arises from the first three branchial arches and forms the supporting structure of the jaws
Dermatocranium- Bony parts of the skull derived from ossifications in the dermis of the skin
Hyaline cartilage- cartilage consisting of cells embedded in an apparently homogeneous matrix, present in joints and respiratory passages, and forming most of the fetal skeleton
Calcified cartilage- flexible connective tissue found in many areas in the bodies of humans and other animals, including the joints between bones, the rib cage, the ear, the nose, the elbow, the knee, the ankle, the bronchial tubes and the intervertebral discs. It is not as hard and rigid as bone but is stiffer and less flexible than muscle
Fibrocartilage- cartilage in which the matrix except immediately about the cells is largely composed of fibers like those of ordinary connective tissue
Diaphysis- the shaft of a long bone
Epiphyses- an end of a long bone
Metaphysic- the transitional zone at which the diaphysis and epiphysis of a bone come together
Endochondral bone -relating to, formed by, or being ossification that takes place from centers arising in cartilage and involves deposition of lime salts in the cartilage matrix followed by secondary absorption and replacement by true bony tissue
membrane bone- a bone that ossifies directly in connective tissue without previous existence as cartilage
heterotopic bone- the percentage of osteoblasts is typically double that of normal bone
Example: formation of bone where it is not normally found, as in muscle
Blastema- a mass of living substance capable of growth and differentiation
Mesenchyme- loosely organized undifferentiated mesodermal cells that give rise to such structures as connective tissues, blood, lymphatics, bone, and cartilage
Chondrocytes- a cartilage cell
Chondroblast - a cell that produces cartilage
Osteocytes- a cell that is characteristic of adult bone and is isolated in a lacuna of the bone substance
osteoblast - a bone-forming cell
osteoclasts- bone cleaning cell
Compact bone - tightly packed tissue/bone
Spongy bone - tissue that makes up the interior of bones
Acellular bone- metabolically active tissue.
Example: Bone tissue in the Actinopterygii
Fontanels- a membrane-covered opening in bone or between bones
Example: any of the spaces closed by membranous structures between the uncompleted angles of the parietal bones and the neighboring bones of a fetal or young skull
Cranial kinesis- ??movement between the upper jaw and braincase
Cranial akinesis - ?skulls cannot perform the. actions of the kinetic skull
Sesamoid cartilages ?
Joints -
Sutures - a stitch used by doctors and surgeons to hold tissue together
Diarthrosis- a freely movable joint
Example: synovial joint
Synanthrosis- an immovable articulation in which the bones are united by intervening fibrous connective tissues
Amphiarthrosis- a slightly movable articulation
Synovial cartilaginous- stringy fluid found in the cavities of synovial joints
Fibrous joints- The fibrous joints are further divided into three types
Example: Sutures are found between bones of the skull. In fetal skulls the sutures are wide to allow slight movement during birth. They later become rigid synarthrodial
Hyostylic - mandibular arch attaches through the hyomandibula.
Craniostylic- incorporated into cranium, jaws (reduced to dentary alone) suspended directly from squamosal bone
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