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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.
2
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1answer
96 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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1answer
195 views

Function of carapace

Majority of crustacean larvae have expanded carapace drawn out into processes as an adaptation for : a. Protection from enemies b. Planktonic habit The answer given is b but I think it should be ...
1
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0answers
175 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 ...
2
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1answer
71 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
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3answers
161 views

Where should I start looking for an online gene library?

Is there an online library that includes all known genes in stored in their nucleotide form of all living organisms? I'm presuming that such a database doesn't exist. So to kick of my search, how ...
1
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0answers
57 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
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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 ...
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4answers
631 views

Punnett Square Help

In fruit flies, red eyes are dominant over white eyes. Show a cross between two white-eye fruit flies. My question is... How do I know if the white-eye fruit flies are homozygous or heterozygous?
7
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2answers
275 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 ...
0
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1answer
58 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 ...
3
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1answer
62 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 ...
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 ...
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 ...
0
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1answer
145 views

Can someone help me analyze this article? [closed]

I need to read this article — "Beyond the rainbow" by Marie-Claire Koschowitz et al., for an exam. Following are some questions for which I could not figure the answer out after reading. 1) Why ...
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 ...
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 ...
0
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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 ...
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 ...
3
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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
568 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
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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
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?
0
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2answers
330 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. ...
1
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1answer
96 views

Why did the yeast rise?

Here are the notes I made for an experiment I was doing (I didn't put it here as it is too long) (please ignore the numbers at the end of the pdf file) The graph looks like this: As you see on ...
-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
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 ...
1
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2answers
112 views

How to use swiss-mod to predict the secondary structure and 3D structure of a protein?

I'm trying to predict the protein secondary and 3-D structure for the sequence [Q1NN20] and need some help getting the ball rolling. I'm getting confused with how and when to use Jpred, swiss-mod, ...
3
votes
1answer
189 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, ...
2
votes
1answer
1k views

recombination frequency problem

Three loci C, D and E are located on the same chromosome in this order. We found that the frequency of recombinants between C and D is 10% and that between D and E it is 20%. Assuming that ...
1
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1answer
2k views

Calculating number of amino acids in mRNA

Assuming there were 20 different amino acids and less than 40 types of different tRNAs found in this alien organism. How many amino acids would be found in the translational product of a ...
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 ...
0
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1answer
628 views

Possible Genotypes — Linked Genes

Please consider the following question: Genes A and B are located on the same chromosome. If two individuals with the genotype shown below are crossed, which genotype could be formed? Let / ...
2
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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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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 ...
5
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2answers
136 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 ...
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
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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) ...
1
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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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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 ...
0
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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 ...
1
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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 ...