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2
votes
1answer
94 views

Techniques to show a protein heterodimer-DNA interaction

It is known that c-Jun and fos dimerize to form AP1 factor that binds to a sequence on DNA containing PyPuGACGTCNNNNGAGGTCPyPU. In esophageal cancer cell lines there is no expression of the fos gene. ...
0
votes
0answers
15 views

Trouble identifying a gene given an Expressed sequence tag

I have an assignment where we need to answer several questions about an EST, however, I'm having trouble getting started. My sequence contained a Not I site (clipped that) and no poly A signal. We ...
1
vote
1answer
140 views

An experiment to test if a bacterial resistance gene is on the plasmid or chromosome?

So I have an E.coli strain phenotypicall resistant to the antibiotics ampicillin and rifampicin. How do I test if the AmpR gene is carried on a plasmid and not on the chromosome? In summary, I ...
1
vote
0answers
44 views

Are there non-essential cell organelles? [closed]

Suppose an eukaryotic animal cell would have to choose to loose an organelle, akin to the voting system of the TV show Big Brother. Which organelle would be the least important to the cell and ...
1
vote
0answers
25 views

How quickly does plant cells regenerate? [closed]

This is a question from my Biology class homework? I've looked online, but I can't find the answer.
3
votes
1answer
114 views

What is the direction of current flow in myelinated nerve cells?

Is it correct to say electric current flows through the extracellular space, or cytosol of a nerve fiber during impulse conduction? I know that an impulse is actually a change of membrane potential ...
2
votes
1answer
124 views

What happens when our muscle tense? [closed]

Is the tensing of muscles equivalent to stretching them? I am trying to understand what tensing of the muscles means.
1
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0answers
238 views

Construct a restriction map of a linear fragment of DNA using the following data?

I've attempted to do the single digests, and the double digests, but cannot complete the map.... I've attached what I've done so far DNA Sizes of Fragments (bp) uncut DNA 900 DNA cut with EcoRI ...
1
vote
0answers
63 views

What would happen if there were no protists? [closed]

This is for an inquiry project for my biology 11 class. I need opinions from some professionals so please help out.:) if you dont mind also putting your name and what you do or what degree you that ...
1
vote
0answers
20 views

What is the site on an enzyme that binds either exitatory or inhibitory molecules? [closed]

A site on an enzyme where either exitatory or inhibitory molecules can bind is called a(n): A) electron transport site B) active site C) coenzyme D) metabolic pathway E) allosteric site If you ...
6
votes
1answer
122 views

How can I make a protein interaction/protein-complex network?

Let's say I have a list of proteins ID. I would like to know whether I can find any complex based on that list. Any example, explanation is appreciated. An example input is what you see below. What ...
3
votes
1answer
67 views

Understanding common identifier codes (IDs) in biology databases

I know this is very basic but I would like to understand it and it's difficult to know where to begin with a new database. I have the output: ...
2
votes
1answer
83 views

Are alpha-ketoglutarate and glutamate involved in all transamination reactions?

Is it true that for all biochemical transamination reactions, that alpha-ketoglutarate and glutamate serve as the amino group acceptor and donor, respectively? If this is true, then is it safe to ...
3
votes
1answer
65 views

Could a single cell be brought to life?

If a scientist is observing a single cell under a microscope, and then realizes that the cell has died, is it possible to bring that dead cell back to life? For my inquiry, let's assume that the ...
0
votes
1answer
66 views

Solving a Pedigree Between Heterozygous Half-Cousins

A man who is a known heterozygous carrier of oculocutaneous albinism marries his half-cousin (they share one common grandparent) as shown in the pedigree below. This trait is transmitted as a fully ...
2
votes
1answer
197 views

What would happen if a cell is poked by a fine needle?

I had seen this question in an exam: A living cell has a protoplasm which is water based and demarcated by a lipid bilayer membrane. If a cell is pierced to 1/5th of its diameter with a very sharp ...
0
votes
1answer
191 views

Find how much times blood is filtered in the kidney? [closed]

The blood that circulates in our body is about 1/12 of our mass. If the kidneys filter 7.5 liter of blood a hour, then how many times does it filter in the kidney the whole blood of a person will mass ...
1
vote
0answers
19 views

Comparing genetics [closed]

Compare the possible effect on an individual of knowing that they have genes predisposing them to type-2 diabetes and the dominant allele that causes Huntington's disease. I am not sure about the way ...
0
votes
1answer
50 views

Which of the following is NOT a type of tropism?

Which of the following plant movements is NOT a tropism? Plant stem growing toward light Plant structure growing away from light Plant roots growing in response to gravity Vines coiling around ...
3
votes
2answers
345 views

Gene and alleles

This is a multiple choice question: Consider a gene, ABC, which codes for an enzyme involved in the metabolism of sugars. There are two known alleles of this gene, ABC1 and ABC2. Which statement ...
1
vote
0answers
66 views

Which of the three is true for insulin receptors?

I have seen the following question in a Cell Biology exam: Which of the following is true" Insulin has an hydrophobic Signal Peptide and the insulin receptor does not have an hydrophobic ...
1
vote
0answers
43 views

Relation between heterozygosity and allelic diversity in founder effects/bottleneck?

Can someone try to explain me why allelic diversity falls faster than heterozygosity, reminding you that we're talking about bottleneck or a founder effect? Look at this graphic: It's clear to me ...
7
votes
2answers
290 views

How many ATP are formed?

What is the number of ATP molecules formed during the photosynthetic processes which consume 8 molecules of $\text{H}_2\text{O}$ due to noncyclic electron transport and subsequent photophosphorylation?...
3
votes
1answer
447 views

Problem: What is this pattern of inheritance?

The following question was on a pretest of mine, and I'm trying to figure out the answer using what we've learned about Mendelian and non-Mendelian patterns of inheritance. I'm struggling quite a lot ...
1
vote
0answers
33 views

Location of CD8 receptor [closed]

I have a multiple choice question that says The CD8 receptor is found on: Ts cells Tc cells Both of them I think it is both of them but I found the answer is Ts cells Could someone explain ...
4
votes
1answer
583 views

Pedigree Analysis: Problem

I'm struggling to arrive at the answer to the following question, which appeared on a pre-test of mine and which I am now using to study the material we've learned. According to this helpful video, I ...
4
votes
1answer
71 views

Determine which seed will germinate first

I recently studied about plant physiology for a test. Strangely, there was this question which I had no idea how to approach. The question is, Which seed will germinate first? a) Castor b) Wheat c)...
1
vote
1answer
36 views

A question involving immunoprecipitation to identify interacting proteins?

Using recombinant Flag-tagged Dcr-2 and His-tagged protein X, pull-down assays were performed to determine whether protein X and Dcr-2 interact directly. The recombinant proteins (either alone or in ...
1
vote
0answers
11 views

Which fractions are enriched for siRNA cleavage activity by comparing electrophoresis?

Size exclusion column chromatography was used to separate the proteins in a Drosophila cell lysate to attempt to identify the protein complex responsible for processing long dsRNA into siRNAs. SDS-...
3
votes
1answer
132 views

Does urea at different concentrations (5 or 0.5M) have different effects on proteins?

The problem is to explain why each additive gives rise to the distribution of the protein (RMAS) as shown in the Western blow below: In each case, the homogenates were subjected to high-speed ...
1
vote
0answers
11 views

final control prior to transfecting an expression vector into a mammalian cell?

I have been asked a general question: Once I have cloned a full-length cDNA into an expression vector, what final important control must I do before I transfect this into an embryonic stem cell line? ...
1
vote
0answers
76 views

Which DNA fragments do not have expected sizes on this gel electrophoresis?

The problem is such: After performing a PCR, the vector carrying the PCR fragment with two restriction enzymes (Nhe1 and Asc1). The DNA samples were then separated using agrose gel electrophoresis ...
2
votes
1answer
51 views

Is there any mechanical digestion that occurs once food/chyme enters the small intestine?

Does mechanical digestion occur in small intestines and, if so, how does it occur? I found some sources that say digestion happens mechanically and chemically in the small bowel, and others that say ...
1
vote
1answer
100 views

Enzymes and plasmids

A high school class has analyzed plasmids by the help of restriction enzymes and electrophoresis. The class got delivered two different plasmids, pBR 322 and pC 508. These two plasmids were going to ...
-2
votes
1answer
78 views

Homework Question: Confused about figure related to cDNA and gDNA

what is the answer in blank? I think the loop structure for the top blank is an intron. I think RNA is the answer for the bottom blank, but it is cDNA, so it can't be RNA. I cannot figure out what ...
1
vote
1answer
63 views

How is the probability of a sequence occuring with BLAST calculated?

What is the probability that a given nucleotide/amino acid sequence will occur in the whole database program BLAST searches in? How this probability is calculated?
1
vote
1answer
115 views

What is enantiostasis?

I have searched around and read my textbook but I am failing to understand how enantiostasis is different to homeostasis. For reference, Wikipedia definition is as follows: Enantiostasis is the ...
3
votes
1answer
226 views

How to perform a DNA structural alignment in pymol

How can I "fit" two DNA structures having different nucleotide sequences in pymol? I would like to use the structure of a DNA binding protein in pdb (1h9t), which is bound to DNA in the pdb file, ...
0
votes
0answers
56 views

Rate of potassium/sodium transport

Assume that the plasma membrane of a cell was suddenly permeable to the same degree to both Na+ and K+ and that each responded to a concentration gradient of the same magnitude. Would you expect these ...
2
votes
0answers
29 views

height and bryophytes

Why does being taller provide advantages for Bryophyta but being shorter is better for Marchantiophyta? What disadvantages could being taller have? I think that by being taller, you have better ...
3
votes
2answers
172 views

Blebbistatin effect on vesicles

Blebbistatin is a drug that specifically inhibits the assembly of myosin in the cytoskeleton. What effect would you expect blebbistatin to have on intracellular vesicles? ...
1
vote
1answer
130 views

Disadvantage of using Drosophila for breeding experiment

What should be the disadvantage of using Drosophila for experiments? a)small size of larva. b)short life cycle. c)mating soon after emergence of flies. d)large number of offsprings. Options (b) and ...
4
votes
1answer
169 views

How do I make a multiple sequence alignment (MSA)?

I have a DNA sequence that makes protein 1, but now I have asked to: compare the amino acid sequence of protein 1 with nine homologous proteins and make a multialignment of the sequences. Determine ...
5
votes
2answers
148 views

Non-ribosomal peptide synthesis: why Glutathione cannot be produced by the ribosome?

Case: I am writing a summary for a class in protein structure and function, and was asked to describe some different ways that peptides are synthesized (that does not involve the ribosome). I ...
1
vote
0answers
28 views

recombination between DNA segments question

In the diagram shown above, segments A and C are copies of a repeated DNA sequence, flanking a unique stretch shown as B. A and C are in an inverted orientation relative to each other, as indicated by ...
1
vote
0answers
120 views

mutations induced by transposons

Question: In contrast to chemically-induced mutations, mutations induced by transposons are more likely to ... be lethal de dominant be stable revert to wild types be a gain of function The ...
1
vote
1answer
60 views

tandem repeat sequence; causes of contraction and/or expansion question

Question: Which of the following events, occurring within a tandem repeat sequence, will cause an expansion or contraction of the array? A) Endoduplication B) homologous recombination C) ...
0
votes
1answer
30 views

kinetics question [closed]

An enzyme has a $V_{max}$ of 50 $\mu$mol product formed $(min * \text{mg protein})^{-1}$ and a $K_m$ of 10 $\mu$M for the substrate. When a reaction mixture contains the enzyme and a 5$\mu$M ...
0
votes
2answers
358 views

Polymerase Chain Reaction Questions

First question is about why we use primers in PCR. It requires two reasons. I know only one reason though. It is so that DNA polymerase can attach to primer and make a copy of nucleotide from there. ...
3
votes
1answer
68 views

Why do some bacteria have an asymmetric replication?

Our teacher said that Bacillus subtilis has an asymmetrical replication fork. I know that this happens only in some strain of the bacteria . She asked us to find an explication for this mechanism , ...