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0
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1answer
142 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
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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
44 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
342 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
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0answers
57 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
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0answers
41 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
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2answers
276 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 ...
3
votes
1answer
439 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
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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
569 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
56 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 ...
1
vote
1answer
33 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
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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. ...
3
votes
1answer
106 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 ...
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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
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0answers
68 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
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0answers
43 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
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1answer
96 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
70 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 ...
1
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1answer
61 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
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1answer
93 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
190 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
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0answers
50 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
28 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 ...
1
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2answers
143 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
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1answer
120 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
158 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
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2answers
137 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 ...
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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 ...
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0answers
106 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
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1answer
56 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
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2answers
331 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
58 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 , ...
1
vote
1answer
22 views

Ways to identify that proteins are regulating different genes experimentally

As part of my study I have been given this hypothesis: HIF 1a and HIF 2a regulate different genes in multiple myeloma What ways do we have to identify that these proteins are regulating ...
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0answers
44 views

Chance of passing a risk allele to child?

Our genetics professor has posted up working for previous examination answers, but I am unsure that one of his answers is correct. My answer is close but may just be due to co-incidence. Question: ...
1
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0answers
73 views

Reasons for strange heart rate graph following exercise (line going up and down)?

Following a 2 minute general jumping and movement exercise designed to involve the entire body, the pulse was taken every minute for ten seconds. Strangely, the graph appears to jump up and down, for ...
1
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0answers
31 views

Invertase calculation?

If I wanted to make $500\mathrm{\mu g}/\mathrm{ml}$ of invertase, from Sigma's Invertase from Baker's yeast, which states is grade VII, and greater than or equal to $300 \mathrm{units}/\mathrm{ml}$, ...
1
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2answers
79 views

“structural and regulatory elements of genes” [closed]

Can anyone please explain a little about these two elements of genes? My main problem is with "which ‘switch on’ instructions". genes have structural elements (which code for a particular protein) ...
1
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0answers
50 views

Calculating the recombination factor of four point genetic cross?

So, I'm trying to work out the recombination factor (RF) from this set of data: Which shows the 16 phenotypes of progeny of a cross of Saccharomyces cerevisiae yeast. I know how to go about a three ...
3
votes
1answer
120 views

What is a holocentric chromosome?

I was doing this question that asked: "How many centromeres does a typical chromosome have?" I thought one and the answer was:"One, except for holocentric chromosomes." So then what are ...
1
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0answers
141 views

Evolution of a Population

Scientists observe a newly established population of sexually reproducing plants growing on the shore of a small island. An observable trait of the plant has two possible phenotypes. It is determined ...
1
vote
1answer
377 views

Hardy-Weinberg Equilibrium Question

I have four questions concerning H-W Equilibrium: (i) In a population of mice, the presence of black spots is the result of a homozygous recessive condition. If the frequency of the allele for this ...
1
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0answers
113 views

How can we determine the polarity of fat molecules?

I'm trying to solve a question in a biochemistry quiz, which is asking for classifying a set of lipidic derivatives, by increasing polarity. Unfortunately, we didn't cover the classification of ...
1
vote
1answer
197 views

Albinism inheritance problem: what are the father's alleles if he got an albino kid?

Albinism is caused by a recessive gen "c". A normal man marries an albino woman. The first son happened to be albino. What are the possible phenotypes of the parents? What is the chance that ...
3
votes
0answers
106 views

Cause-and-effect questions about growth and development of plant

I need to solve some cause-and-effect problems. The problems are related to growth and development of plant. "Growth and Development" chapter is the first chapter in third level of high school (senior ...
3
votes
2answers
98 views

Is numbness the absence of one or all touch sensations?

I am studying the effects of tetrodotoxin and its symptoms when consumed. Numbness is one of the first sensations reported. But I googled numbness and I couldn't find information about whether this ...
5
votes
1answer
227 views

How to calculate the percentage of heterozygous cells based on a gene map

I've encountered the following question and am quite stumped by it. A female with genotype AABBCC has been hybridized with a male that has the genotype aabbcc. The first generation (F1) has been ...
2
votes
1answer
49 views

Hodgin-Huxley model for a single neuron - continuation

As continuation to This question I have posted. Another set of questions is given for the same model : This time it is also given that for $t<0$ the membrane potential is $u_0$, and at $t=0$ it ...
3
votes
1answer
73 views

Hodgin-Huxley model for a single neuron

I am viewing (through edX ) an introduction course to computational neuroscience. In the second lecture, the Hodgin-Huxley model is considered. I am going over some of the questions and have ...