Take this test part 4:

[osimsDDS]

"take this test part n" where n is an integer is my new slogan...enough gibber jabber lets get down to business homies...

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria
b) it shunts blood away from the pulmonary circulation
c) it shunts blood away from the liver
d) it shunts blood away from the kidneys
e) it shunts blood away from systemic circulation

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria
b) it shunts blood away from the liver
c) it shunts blood away from the placenta
d) it shunts blood away from the umbillical cord
e) none of the above

3) From what germ layer does the nueral tube arise from?
a) ectoderm
b) mesoderm
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera
b) it is the nerve responsible for the innervation of the diaphragm
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system
e) all of the above

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+
b) Na+
c) K+
d) Ca2+
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93%
c) 85%
d) 91%
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5%
c) 9%
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2
d) Just ethanol
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial
c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated
d) euchromatin are heavily methylated


I was gonna have 5 questions but i couldnt stop writing haha, hopefully these questions are good , enjoy...

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[pistolpete007]

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria-foramen ovule
b) it shunts blood away from the pulmonary circulation-ductus arterious
c) it shunts blood away from the liver
d) it shunts blood away from the kidneys-what does this
e) it shunts blood away from systemic circulation what does this

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria
b) it shunts blood away from the liver
c) it shunts blood away from the placenta what does this
d) it shunts blood away from the umbillical cord what does this
e) none of the above

3) From what germ layer does the nueral tube arise from?
a) ectoderm
b) mesoderm-notocord
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera
b) it is the nerve responsible for the innervation of the diaphragm
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system-whats the key never for this vagus?
e) all of the above

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+
b) Na+
c) K+
d) Ca2+?
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10? im always gonna have a problem with these quesitons

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93% p=.70 q=.3.....p^2 +2pq=91
c) 85%
d) 91%
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5% 100-91=9 too bad they wont make it like this on the real DAT back to back problems...but it should q^2=.09=9%
c) 9%
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2
d) Just ethanol?
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial....do u think questions are indepth like this one on the real dat i just happen to knnow this quesiton both protosome are bilateral and deuterostomes can be radial(echinoderms) or bilateral chordates but when talking bout the cleavage deuterostomes demonstrate radial indeterminate cleavage where as protsomes deomonstrate spiral determinate clevage

c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated
d) euchromatin are heavily methylated
schaums kind of confused me on the whole methylation thing....

 

[wkawk2416]

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria
b) it shunts blood away from the pulmonary circulation
c) it shunts blood away from the liver
d) it shunts blood away from the kidneys
e) it shunts blood away from systemic circulation

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria
b) it shunts blood away from the liver
c) it shunts blood away from the placenta
d) it shunts blood away from the umbillical cord
e) none of the above

number 1,2 i am asummung you are talking about fetus

3) From what germ layer does the nueral tube arise from?
a) ectoderm
b) mesoderm
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera
b) it is the nerve responsible for the innervation of the diaphragm
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system
e) all of the above

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+
b) Na+
c) K+
d) Ca2+
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93%
c) 85%
d) 91%
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5%
c) 9%
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2
d) Just ethanol
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial
c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated
d) euchromatin are heavily methylated



good questions.

 

[sl2obel2ts]

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria
b) it shunts blood away from the pulmonary circulation
c) it shunts blood away from the liver<
d) it shunts blood away from the kidneys
e) it shunts blood away from systemic circulation

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria <
b) it shunts blood away from the liver
c) it shunts blood away from the placenta
d) it shunts blood away from the umbillical cord
e) none of the above

3) From what germ layer does the nueral tube arise from?
a) ectoderm<
b) mesoderm
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation<

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera
b) it is the nerve responsible for the innervation of the diaphragm <
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system
e) all of the above

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+
b) Na+
c) K+
d) Ca2+<
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10<

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93%
c) 85%
d) 91%<
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5%
c) 9%<
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2 <
d) Just ethanol
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial <
c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated
d) euchromatin are heavily methylated <

 

[phungy]

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria
b) it shunts blood away from the pulmonary circulation
c) it shunts blood away from the liver
d) it shunts blood away from the kidneys
e) it shunts blood away from systemic circulation

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria
b) it shunts blood away from the liver
c) it shunts blood away from the placenta
d) it shunts blood away from the umbillical cord
e) none of the above

3) From what germ layer does the nueral tube arise from?
a) ectoderm
b) mesoderm
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera
b) it is the nerve responsible for the innervation of the diaphragm
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system
e) all of the above
No idea. Edit: Looked up wiki, answer is B

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+
b) Na+
c) K+
d) Ca2+
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93%
c) 85%
d) 91%
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5%
c) 9%
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2
d) Just ethanol
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial
c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated
d) euchromatin are heavily methylated

Love the questions, make harders ones

 

[sweetpea2]

These are helpful, do you make these questions up yourself??

Also, can someone explain #7. My reasoning is that there are 10 chromosomes so by anaphase they are split so 5 chromosomes in each daughter would = 10 chromatids. Is this correct, and does this mean that at metaphase there would be 20 chromatids. Thanks

 

[osimsDDS]

"take this test part n" where n is an integer is my new slogan...enough gibber jabber lets get down to business homies...

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria
b) it shunts blood away from the pulmonary circulation
c) it shunts blood away from the liver
d) it shunts blood away from the kidneys
e) it shunts blood away from systemic circulation

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria
b) it shunts blood away from the liver
c) it shunts blood away from the placenta
d) it shunts blood away from the umbillical cord
e) none of the above

3) From what germ layer does the nueral tube arise from?
a) ectoderm
b) mesoderm
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera -----> vagus nerve
b) it is the nerve responsible for the innervation of the diaphragm
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system
e) all of the above

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+
b) Na+
c) K+
d) Ca2+
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10[/COLOR] The homologous chromosomes split but you still have the same amount of chromosomes...

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93%
c) 85%
d) 91%
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5%
c) 9%
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2....alcohol fermentation produces these 2 products
d) Just ethanol
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial
c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated
d) euchromatin are heavily methylated


I was gonna have 5 questions but i couldnt stop writing haha, hopefully these questions are good , enjoy...

Good job people most did very well....

 

[joshmonsta]

Is the answer to #7 correct? I thought that at the beginning of both mitosis and meiosis there were 2N chromosomes and 4N chromatids. There will still be 2N chromasomes and 4N chromatids until the end of Telophase I, then each cell will have 1N chromosomes and 2N chromatids. At the end of Telophase II each cell will have 1N chromosomes and 1N chromatids. That would make 20 chromatids (and 10 chromosomes) present at the end of Anaphase I. That is my impression anyway.

 

[Mstoothlady2012]

Is the answer to #7 correct? I thought that at the beginning of both mitosis and meiosis there were 2N chromosomes and 4N chromatids. There will still be 2N chromasomes and 4N chromatids until the end of Telophase I, then each cell will have 1N chromosomes and 2N chromatids. At the end of Telophase II each cell will have 1N chromosomes and 1N chromatids. That would make 20 chromatids (and 10 chromosomes) present at the end of Anaphase I. That is my impression anyway.

The key here is that 10 represents the diploid number, meaning that it already includes the homologous chromosomes so you do not need to multiply it again by 2. Now solve it!

 

[harrygt]

Good test as usual. Thanks OSIMS. However, the answer to 7 should be 20 [d].
I got all of them right except 11 and also the one about the sea urchin. I doubt if we are supposed to know that much in detail about the sear urchin and all that stuff. I mean, the Ca+ being responsible for the block of polyspermy seems to be a very detailed question. Agree?
BTW, I'm waiting for test number 5. Hurry up! lol
explanation for 7 : in anaphase I, you still have the same number of chromosomes, which are moving toward the poles. Each chromosome still has two chromatids. so you will have 10 x 2 chromatids. Don't know how you came up with 10!
By the way, where do you get the questions from?

 

[Mstoothlady2012]

Good test as usual. Thanks OSIMS. However, the answer to 7 should be 20 [d].
I got all of them right except 11 and also the one about the sea urchin. I doubt if we are supposed to know that much in detail about the sear urchin and all that stuff. I mean, the Ca+ being responsible for the block of polyspermy seems to be a very detailed question. Agree?
BTW, I'm waiting for test number 5. Hurry up! lol
explanation for 7 : in anaphase I, you still have the same number of chromosomes, which are moving toward the poles. Each chromosome still has two chromatids. so you will have 10 x 2 chromatids. Don't know how you came up with 10!
By the way, where do you get the questions from?

I believe the question says that 2N=10. Meiosis I goes from 2N ---> N. so now each cell has N=5 chromosomes. Each chromosome has 2 chromatids, so 5 x 2 = 10

 

[osimsDDS]

Good test as usual. Thanks OSIMS. However, the answer to 7 should be 20 [d].
I got all of them right except 11 and also the one about the sea urchin. I doubt if we are supposed to know that much in detail about the sear urchin and all that stuff. I mean, the Ca+ being responsible for the block of polyspermy seems to be a very detailed question. Agree?
BTW, I'm waiting for test number 5. Hurry up! lol
explanation for 7 : in anaphase I, you still have the same number of chromosomes, which are moving toward the poles. Each chromosome still has two chromatids. so you will have 10 x 2 chromatids. Don't know how you came up with 10!
By the way, where do you get the questions from?

You are correct I messed up, it is supposed to be 20 chromatids....because the cell has not split yet, so there are still 20 chromatids in the cell, only after telophase I will the chromatid number be reduced to 10...my bad everyone...20 is the right number. Thats pretty important stuff, good eye

 

[Mstoothlady2012]

You are correct I messed up, it is supposed to be 20 chromatids....because the cell has not split yet, so there are still 20 chromatids in the cell, only after telophase I will the chromatid number be reduced to 10...my bad everyone...20 is the right number. Thats pretty important stuff, good eye

wait I don't understand this...can you plz explain?

 

[harrygt]

I believe the question says that 2N=10. Meiosis I goes from 2N ---> N. so now each cell has N=5 chromosomes. Each chromosome has 2 chromatids, so 5 x 2 = 10

Mstoothlady, check it again. that is at the end of meiosis I [Telophase I] when 2n---> n. In anaphase I, you still have all the chromosomes intact in one cell, just moving to the poles. Each chromosome still has 2 chromatics. [the chromatics are separated in anaphase II].

*****There is no replication, once meiosis starts!! Replication of DNA is at the S phase, which is before G2 .

 

[Mstoothlady2012]

ooohhh!!! I get it....Meiosis I is not complete yet...so we are are still in 2N....nvm lol

 

[Mstoothlady2012]

Mstoothlady, check it again. that is at the end of meiosis I [Telophase I] when 2n---> n. In anaphase I, you still have all the chromosomes intact in one cell, just moving to the poles. Each chromosome still has 2 chromatics. [the chromatics are separated in anaphase II].

*****There is no replication, once meiosis starts!! Replication of DNA is at the S phase, which is before G2 .

yes I just realized...thnx. sorry for the confusion! little tricky there.

 

[harrygt]

ooohhh!!! I get it....Meiosis I is not complete yet...so we are are still in 2N....nvm lol

Good... "Now solve it!" (Mstoothlady2012) j/k

 

[Mstoothlady2012]

Good... "Now solve it!" (Mstoothlady2012) j/k

lol...uhh!! meannnn

 

[harrygt]

lol...uhh!! meannnn

Lol, sorry for the joke I have been doing these types of 2N, N problems since my junior high school year in Europe [Not in U.S]. That is why I never miss any of them. They are not actually hard ones as they look to be. Anyone who can visualize the entire cycle in their head, will be able to ace those problems in 10 secs.
I sent you a message. When are you taking DAT?

 

[sweetpea2]

Harrygt...can you just explain the 2N and N chromosomes. When we mention the diploid 2N number does that mean that we have 10 chromosomes??? So 20 chromatids. And so in mitosis this number will always stay the same while in meiosis it will be halved after telophase. Thanks

 

[osimsDDS]

Here is an example (correct me if i am wrong):

2N=20

Meiosis Prophase I: 40 chromatids, 20 sister chromatids, 20 chromosomes
Meiosis Metaphase I: 40 chromatids, 20 sister chromatids, 20 chromosomes
Meiosis Anaphase I: 40 chromatids, 20 sister chromatids, 20 chromosomes
Meiosis Telophase I: 20 chromatids, 10 sister chromatids, 10 chromosomes

Meiosis Prophase II: 20 chromatids, 10 sister chromatids, 10 chromosomes
Meiosis Metaphase II: 20 chromatids, 10 sister chromatids, 10 chromosomes
Meiosis Anaphase II: 20 chromatids, 0 sister chromatids, 20 chromosomes
Meiosis Telophase II: 10 chromatids, 0 sister chromatids, 10 chromosomes

 

[theedaddy77]

i had a question about the 2n and N and what specifically do they represent is it if it says n=5 that means you have 5 chromosomes and if it is 2n=10 that means you have 5 homologous chromosomes so u have in fact 10 chromosomes?

 

[harrygt]

sweetpea, ok, whenever we say 2n or n, we are only and only talking about the number of chromosomes. For finding the number of chromatids, you gotta have a good understanding of the cell cycle and anything that happens at each stage.
Lets say 2n = 10, this means the begining cell which is supposed to start the cycle [in prophase] has 10 chromosomes [5 pairs of homologous chromosomes]. Now you gotta know that all chromosomes in prophase have 2 chromatics , so that would give you 20 chromatics in prophase I.
Anaphase one is the same as prophase, the only differece being the separation of chromosomes to the poles.
Please come up with a more clear question in the second part of your previous post. I did not get what you meant. Mitosis is pretty much different. It looks like Meiosis II.

Here are 3 questions I will post for anyone who would like to answer.:

1) There are 16 chromatics at the end of anaphase II in the cell. What was the number of chromosomes in Prophase I?

2) A cell has 60 DNA molecules in prophase I. How many centromeres are there at the end of anaphase II?

3) A gamete has 10 DNA molecules. WHat was the 2n chromosomal number in the primary spermatocyte [prophase I]?

Answers will come later.

 

[harrygt]

Here is an example (correct me if i am wrong):

2N=20

Meiosis Prophase I: 40 chromatids, 20 sister chromatids, 20 chromosomes
Meiosis Metaphase I: 40 chromatids, 20 sister chromatids, 20 chromosomes
Meiosis Anaphase I: 40 chromatids, 20 sister chromatids, 20 chromosomes
Meiosis Telophase I: 20 chromatids, 10 sister chromatids, 10 chromosomes

Meiosis Prophase II: 20 chromatids, 10 sister chromatids, 10 chromosomes
Meiosis Metaphase II: 20 chromatids, 10 sister chromatids, 10 chromosomes
Meiosis Anaphase II: 20 chromatids, 0 sister chromatids, 10 chromosomes
Meiosis Telophase II: 10 chromatids, 0 sister chromatids, 10 chromosomes

OsimsDDS, You gotta a small mistake in the Meiosis Anaphase II. It should be 20 chromatids, and 20! chromosomes. you have to consider that once the sister chromatids are separated, each chromatid is called a chromosome now.
Good job anyway!

 

[theedaddy77]

1) There are 16 chromatics at the end of anaphase II in the cell. What was the number of chromosomes in Prophase I?
16 chromotids mean u have 8 chromsome but it split once so in prophase u have 64 chrmotids so 16 chromosome


2) A cell has 60 DNA molecules in prophase I. How many centromeres are there at the end of anaphase II? wtf molecules well dna is wrapped together therefore each chrmosome i guess can be considered one molecule..... so u would have so it would split 2 so 15 chromosome



3) A gamete has 10 DNA molecules. WHat was the 2n chromosomal number in the primary spermatocyte [prophase I]? 40?

Answers will come later.

 

[osimsDDS]

sweetpea, ok, whenever we say 2n or n, we are only and only talking about the number of chromosomes. For finding the number of chromatids, you gotta have a good understanding of the cell cycle and anything that happens at each stage.
Lets say 2n = 10, this means the begining cell which is supposed to start the cycle [in prophase] has 10 chromosomes [5 pairs of homologous chromosomes]. Now you gotta know that all chromosomes in prophase have 2 chromatics , so that would give you 20 chromatics in prophase I.
Anaphase one is the same as prophase, the only differece being the separation of chromosomes to the poles.
Please come up with a more clear question in the second part of your previous post. I did not get what you meant. Mitosis is pretty much different. It looks like Meiosis II.

Here are 3 questions I will post for anyone who would like to answer.:

1) There are 16 chromatics at the end of anaphase II in the cell. What was the number of chromosomes in Prophase I? 16 chromosomes, 16 sister chromatids, 32 chromatids during prophase I

2) A cell has 60 DNA molecules in prophase I. How many centromeres are there at the end of anaphase II? 30 centromeres? I am assuming by DNA molecule you mean 60 = 2N but not sure

3) A gamete has 10 DNA molecules. WHat was the 2n chromosomal number in the primary spermatocyte [prophase I]? Again not sure what you mean by DNA molecules...chromosomes??? N=10, primary spermatocyte = 2N = 20

Answers will come later.

nice

 

[Mstoothlady2012]

OsimsDDS, You gotta a small mistake in the Meiosis Anaphase II. It should be 20 chromatids, and 20! chromosomes. you have to consider that once the sister chromatids are separated, each chromatid is called a chromosome now.
Good job anyway!

I actually got that one the first time I read yay!!

 

[osimsDDS]

1) There are 16 chromatics at the end of anaphase II in the cell. What was the number of chromosomes in Prophase I?
16 chromotids mean u have 8 chromsome but it split twice so in prophase u have 64 chrmotids so 32 chromosome


2) A cell has 60 DNA molecules in prophase I. How many centromeres are there at the end of anaphase II? wtf molecules well dna is wrapped together therefore each chrmosome i guess can be considered one molecule..... so u would have so it would split 2 so 15 chromosome



3) A gamete has 10 DNA molecules. WHat was the 2n chromosomal number in the primary spermatocyte [prophase I]? 40?

Answers will come later.

16 chromatids means you have 16 chromosomes...each chromatid at the end of anaphase II = 1 chromosome

 

[Mstoothlady2012]

sweetpea, ok, whenever we say 2n or n, we are only and only talking about the number of chromosomes. For finding the number of chromatids, you gotta have a good understanding of the cell cycle and anything that happens at each stage.
Lets say 2n = 10, this means the begining cell which is supposed to start the cycle [in prophase] has 10 chromosomes [5 pairs of homologous chromosomes]. Now you gotta know that all chromosomes in prophase have 2 chromatics , so that would give you 20 chromatics in prophase I.
Anaphase one is the same as prophase, the only differece being the separation of chromosomes to the poles.
Please come up with a more clear question in the second part of your previous post. I did not get what you meant. Mitosis is pretty much different. It looks like Meiosis II.

Here are 3 questions I will post for anyone who would like to answer.:

1) There are 16 chromatics at the end of anaphase II in the cell. What was the number of chromosomes in Prophase I?
16 chromosomes

2) A cell has 60 DNA molecules in prophase I. How many centromeres are there at the end of anaphase II?
o centromeres

3) A gamete has 10 DNA molecules. WHat was the 2n chromosomal number in the primary spermatocyte [prophase I]?
2n = 20

Answers will come later.

-

 

[harrygt]

Regarding the question dealing with DNA molecules.... Each chromatid is composed of one molecule of DNA + some proteins + water.
Let's say the cell has 20 DNA molecules. HOw many chromosomes are there? WE DON'T KNOW!!! There are definitely 20 chromatids out there, but for the number of chromosomes, First you have to figure out whether your chromosomes have one chromatid or two by using your knowledge about the stages. Osimdds, you got all the answers right, however, I think you got the answer to the second one accidentally. Number of DNA = Number of chromatids [not necessarily equal to the number of chromosomes, but it could be as I explained]. Hit me up with questions if you have any.

 

[harrygt]

-

to MSLADY2012..Number of centromeres in a cell is always equal to the number of CHROMOSOMES in the cell. This can't be zero. Also refer to my previous answer.

 

[Mstoothlady2012]

to MSLADY2012..Number of centromeres in a cell is always equal to the number of CHROMOSOMES in the cell. This can't be zero. Also refer to my previous answer.

I thought centromere holds 2 sister chromatids together. After anaphase II we dont have any sister chromatids. All we have is 1 chromatid/chromosome. I dont get it???

 

[joshmonsta]

This has gotten far to complicated.

 

[harrygt]

I thought centromere holds 2 sister chromatids together. After anaphase II we dont have any sister chromatids. All we have is 1 chromatid/chromosome. I dont get it???

Each chromosome has one centromere, no matter it is made of one or two chromatids. WHen the two sister chromatids of a chromosome get separated in anaphase II, you get two chromosomes [each made of one chromatid now], and therefore you have two centromeres [equal to number of chromosomes].
Let me say it this way: a centromere holds two sister chromatids together, but it is also present in chromosomes that have only one chromatid.
Actually, if you wanna get into more details: centromere is composed of a protein. During the separation of sister chromatids, centromere replicates [has nothing to do with DNA rep]. Ok, this is too much. Just know that the number of centromeres is always equal to the number of chromosomes.

 

[Mstoothlady2012]

Each chromosome has one centromere, no matter it is made of one or two chromatids. WHen the two sister chromatids of a chromosome get separated in anaphase II, you get two chromosomes [each made of one chromatid now], and therefore you have two centromeres [equal to number of chromosomes].
Let me say it this way: a centromere holds two sister chromatids together, but it is also present in chromosomes that have only one chromatid.
Actually, if you wanna get into more details: centromere is composed of a protein. During the separation of sister chromatids, centromere replicates [has nothing to do with DNA rep]. Ok, this is too much. Just know that the number of centromeres is always equal to the number of chromosomes.

ok! thanks....I am starting to forget my genetics. Its been 1 yr.

 

[harrygt]

FINAL ANSWERS

Here are 3 questions I will post for anyone who would like to answer.:

1) There are 16 chromatics at the end of anaphase II in the cell. What was the number of chromosomes in Prophase I? 16

There are 2n chromosomes at the end of anaphase II [remember: each separated chromatid is a chromosome now]. so if 2n = 16, then that is exactly what we were looking for! we were looking for the number of chromosomes in prophase I which is 2n. [the answer can be interpreted in different ways]

2) A cell has 60 DNA molecules in prophase I. How many centromeres are there at the end of anaphase II? 30

60 DNA = 60 Chromatids in prophase I = 30 chromosomes in prophase I = 15 chromosomes at metaphase II and also the begining of anaphase II = 30 chromosomes at the end of anaphase II = 30 centromeres. [number of centromeres is always equal to the number of CHROMOSOMES]

3) A gamete has 10 DNA molecules. WHat was the 2n chromosomal number in the primary spermatocyte [prophase I]? 20

10 DNA = 10 chromatids at telophase II [the gamete] = 10 chromosomes at telophase II [remember: each chromosome is made of only on chromatid in a gamete] ----> n = 10, so 2n in a spermatocyte would be equal to 20

I hope this heleped!

 

[DRHOYA]

1) What is the function of the ductus venosus?
a) it shunts blood directly from the right atria to the left atria
b) it shunts blood away from the pulmonary circulation
c) it shunts blood away from the liver
d) it shunts blood away from the kidneys
e) it shunts blood away from systemic circulation

2) What is the function of the foramen ovale?
a) it shunts blood from the right atria to the left atria
b) it shunts blood away from the liver
c) it shunts blood away from the placenta
d) it shunts blood away from the umbillical cord
e) none of the above

3) From what germ layer does the nueral tube arise from?
a) ectoderm
b) mesoderm
c) blastula
d) endoderm
e) cleavage

4) Which statement is correct?
a) new nucleotides enter the P site in the process of elongation during translation
b) new nucleotides enter the E site in the process of elongation during translation
c) new nucleotides enter the A site in the process of termination during translation
d) new nucleotides enter the A site in the process of elongation during transcription
e) new nucleotides enter the A site in the process of elongation during translation

5) What is the role of the phrenic nerve?
a) It is the nerve responsible for innervation of the viscera
b) it is the nerve responsible for the innervation of the diaphragm
c) it is the nerve responsible for the hypothalamus
d) it is the key nerve responsible in the parasympathetic nervous system
e) all of the above

6) What ion is responsible for the cortical reaction during the slow block to polyspermy in sea urchins?
a) Mg2+ (guessing)
b) Na+
c) K+
d) Ca2+
e) Iron

7) How many chromatids are present during Anaphase I of meiosis, if 2N=10?
a) 0
b) 5
c) 15
d) 20
e) 10

8) If the frequency of the dominant allele is 70% then what is the frequency of the dominant phenotype in the population?
a) 95%
b) 93%
c) 85%
d) 91%
e) 92%

9) For the above question, what is the frequency of the recessive phenotype in the population?
a) 2%
b) 5%
c) 9%
d) 10%
e) 12%

10) During alcohol fermentation what products are produced?
a) lactate and H2S
b) Methanol and H2S
c) Ethanol and CO2
d) Just ethanol
e) Just CO2

11) What type of cleavage is associated with protostomes and deuterostomes respectively?
a) radial and bilateral
b) spiral and radial
c) radial and spiral
c) spiral and spiral
d) spiral and bilateral
e) Bilateral and spiral

12) All are true about Euchromatin except?
a) Euchromatin occurs in eukaryotic cells
b) euchromatin is a means of gene regulation in eukaryotes
c) euchromatin are heavily acetylated (no clue on this one)???
d) euchromatin are heavily methylated


Thanks man!