Questions
Write a full description of the importance and different types of fermentation carried out by bacteria.

Write a full description of the importance and different types of fermentation carried out by bacteria.

In: Biology

For a diploid mouse cell (40 chromosomes), state how many copies of each are present at...

For a diploid mouse cell (40 chromosomes), state how many copies of each are present at the following cell cycle stages:

Cell cycle stage

Number of chromosomes per cell Number of sister chromatids per cell   Number of centromeres per cell Number of chromosome copies attached to each centromere

G1 phase

G2 phase
Prophase
Anaphase

A researcher has synchronized two different E. coli cultures so that all of the cells enter cell division simultaneously. One culture is wild-type E. coli cells, and the other culture is a mutant E. coli that does not have the gene for Dam methylase. He isolates the DNA from both wild-type and mutant E. coli 20 minutes after replication is complete. What is the methylation state for each strain of E. coli? What would be the methylation state for each bacterial strain if you isolated the DNA immediately after replication termination?

In: Biology

Red-green color blindness is caused by a mutation in a gene on the X chromosome. Xa...

Red-green color blindness is caused by a mutation in a gene on the X chromosome. Xa is the recessive mutant allele that causes color blindness; XA is the dominant, functional allele. You meet a patient who has Klinefelter syndrome (that is, he has an XXY karyotype). His mother is color blind, but his father has normal color vision. Your patient has both the XA and the Xa alleles.

  1. You hypothesize that your patient’s syndrome is due to a meiotic nondisjunction event that occurred in: (circle the correct options) (2 pts)

this patient                this patient’s father              this patient’s mother

                                                Meiosis I         or        Meiosis II

  1. In the space provided below, illustrate how the meiotic nondisjunction event occurred, showing only the sex chromosomes. If you think it could happen in either meiosis I or II, pick one of these for illustration. (6 pts)
  1. Use the symbols below to illustrate the X and Y chromosomes:
  2. Use arrow(s) to indicate the cell(s) that could give rise to your patient’s abnormal karyotype.
  1. You also find a small number of cells in this patient with only one X and one Y chromosome. Explain this phenomenon in no more than two sentences. Be specific about in which individual and roughly when this relevant event might have taken place. (2 pts)

In: Biology

Describe the fate of a single molecule of glucose as it goes through glycolysis and exits...

Describe the fate of a single molecule of glucose as it goes through glycolysis and exits the Krebs cycle. Include the inputs to each reaction and all end products including all created energy storage molecules.

In: Biology

Molecular dynamic simulation of protein- ligand complex. How do I set up a molecular dynamic simulation...

Molecular dynamic simulation of protein- ligand complex.
How do I set up a molecular dynamic simulation for a protein- ligand complex with a cobalt in the 2++ state? In other words, are there topology and parameter files that contain parameter for cobalt ion which are compatible with NAMD?

In: Biology

Describe the ways in which meiosis contributes to genetic diversity within a population in which 2n=20.

Describe the ways in which meiosis contributes to genetic diversity within a population in which 2n=20.

In: Biology

3. Assume that a bacterial culture is grown on medium containing radioactive thymine until essentially all...

3. Assume that a bacterial culture is grown on medium containing radioactive thymine until essentially all of the thymine in the DNA is radioactive. Then the bacteria with labeled T were washed and transferred to a medium containing nonradioactive T for one round of replication. Given the four double stranded sequences below, which one is likely to represent the replicated double stranded structure? Note: A,C,T,G represent typical nucleotides, and 3T represents labeled T.)

1 2 3 4
One strand

A G 3T C

A G 3T C

A G 3T C A G 3T C
One strand A G T C

T C A G

U C 3A G 3T C A G

In PCR reactions, the only enzyme that is needed is a polymerase. Provide reasoning as to why the following essential replication enzymes/components are not needed:

Helicase

Topoisomerase

Ligase

Primase

Replication clamp

In: Biology

Compare and contrast the process of substrate-level phosphorylation, oxidative phosphorylation, and photophosphorylation. Provide one example of...

Compare and contrast the process of substrate-level phosphorylation, oxidative phosphorylation, and photophosphorylation. Provide one example of how each is used in a biological cell.

In: Biology

You isolate nuclei from three different eukaryotic species. You treat the samples in exactly the same...

You isolate nuclei from three different eukaryotic species. You treat the samples in exactly the same way (adding same amount of enzyme, buffer and time) to partially digest the chromatin with micrococcal nuclease, extract the DNA, and run it on a gel. You see the pattern below:

Lane

Approximate size of bands (in base pairs)

1

200, 400, 600, 800

2

180, 360, 540, 720

3

190, 380, 570, 760

a-2pts) Knowing that the core-DNA in all cell types is the same what is your explanation for the difference in size in the patterns you observe (shown below):

b- 2pts) If you digested each of the three samples more thoroughly, what would the pattern look like? [Be specific and indicate what the size of the bands would be]

c-3pt) An explorer discovers a strange new species of plant and sends some of the plant tissue to a geneticist to study. The geneticist performs the kinds of experiments as described above in (b) except that: After digestion with nuclease 120-bp fragment of DNA are seen.
Analysis of the histone core reveals histones in the following proportions:

H2A 33.3%
H2B 33.3%
H3 0% [no histone H3 found]

H4 33.3%

On the basis of these observations, what conclusions could the geneticist make about the probable structure of the nucleosome in the chromatin of this plant? Be specific in describing the nature of the nucleosome: which histones form the core (1pt), how many of each are in there (1pt) and how much core-DNA is around it (1pt).

d-2pt) The geneticist also found H1 and a new histone H7 when histones were extracted from all of the chromatin (not just the nucleosome). What do you think the role of the new histone H7 would be in this new plant species?

In: Biology

what are the steps you will take to isolate and identify a salmonella sp.

what are the steps you will take to isolate and identify a salmonella sp.

In: Biology

Compare and contrast the chromosome structure of viruses, bacteria, and eukaryotes.

Compare and contrast the chromosome structure of viruses, bacteria, and eukaryotes.

In: Biology

Regarding the mitotic cell cycle, what is meant by a checkpoint?

Regarding the mitotic cell cycle, what is meant by a checkpoint?

In: Biology

1. What are 3 ways by which bacteria can overcome, evade or avoid phagocytosis? 3pts 2....

1. What are 3 ways by which bacteria can overcome, evade or avoid phagocytosis? 3pts

2. Some bacteria can stop the activation of complement. Suggest 2 things bacteria might do to complement proteins to stop or prevent complement activation. Describe how stopping complement activation would protect the bacteria. 4pts

3. Explain how CD8, CD4 and B cells work together either in the lymphoid tissue OR at the site of infection.

In: Biology

1. Briefly describe 2 possible effects that antibiotics have on bacteria (ie- 2 things antibiotics can...

1. Briefly describe 2 possible effects that antibiotics have on bacteria (ie- 2 things antibiotics can do to the bacterial cell). Indicate whether each effect is bactericidal or bacteriostatic. 5pts (you may name a 3rd effect for 1 extra credit point)

2. Would B cell activation occur in a person who has NO dendritic cells (DC)? Explain. 5pts

3. Is it a good idea to treat the flu with anti-bacterial antibiotics? Explain. 5pts

In: Biology

What traits do elephants have in common with primates? What traits do octopus have in common...

What traits do elephants have in common with primates?

What traits do octopus have in common with primates?

What important primate traits do elephants lack?

What importants primate traits do octopus lack?

In: Biology