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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? ...
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2answers
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What are sex linked traits?

Which of the two definitions of sex-linked trait is correct? Traits controlled by genes present on the non-homologous region of sex chromosomes are called ...
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1answer
30 views

What is the difference between “genetic” and “hereditary”?

What is the difference between the adjectives "genetic" and "hereditary"?
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1answer
26 views

Why do mutations in Drosophila dsx (double sex) affect both males and females?

Reason: Loss-of-function mutation of dsx gene in female embryo leads to production of a nonfunctional protein that fails to repress male specific gene expression. So somatic characters of both the ...
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1answer
44 views

True or False: Dideoxynucleotide sequence analysis Question

True or false: Dideoxynucleotide sequence analysis is a template-directed method that makes use of chain terminators that stop DNA synthesis because they lack a 2'OH group. The answer is false. ...
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1answer
78 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. ...
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1answer
58 views

Which organisms have their cell wall made of polysaccharides and amino acids?

I came across a question which somewhat goes like In which of the following kingdom, most of the members have a cell wall made of polysaccharide and amino acids ? - Monera or Fungi. To me it ...
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1answer
35 views

Mendel Genetics: Homework question

I'm looking at a question right now about Mendel genetics..... Q) When Mendel crossed a large number of tall pea plants with short pea plants, all F1 plants were tall. The F2 generation was created ...
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1answer
26 views

Does mechanotransduction of cells play a role in the biocompatibility of titanium?

What exactly is mechanotransduction as the information varies between sources. Some sources indicate that mechanotransduction is the underlying principle where cells pull on the surface they grow on ...
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33 views

Minichromosome maintenance protein structure and function

I am having difficulty answering three homework questions which relate directly to Chong et al. (2000). Questions The authors have determined that MtMCM is able to bind both ssDNA and dsDNA (see ...
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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 ...
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0answers
51 views

Problem involving selfing (inbreeding it with itself) a plant to generate purebred lines

I am working on a past exam problem where the first bit is as follows A plant is repeatably selfed to generate inbred lines. Let $\mathbb{P}(He|He)$ denote the probability that a heterozygous ...
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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 ...
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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 ...
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0answers
34 views

How to gauge the clinical significance of specific cell type presence?

How does one decide whether the presence of certain cell types is clinically important or negligible? Would the presence of certain cells in conjunction with other symptoms be enough, or should it be ...
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0answers
247 views

How many proteins are synthesized in human body throughout life?

My idea to calculate this is: Define up to what age will do the calculation. (for instance 60) Determine how many cells born and died up to that point in life. (by type of cell) Determine how many ...
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0answers
41 views

Elevated transaminases after blood transfusion?

This sparks HCV immediately in my mind. However, there may be other possibilities too. What can you deduce from elevated transaminases if you only know that the healthy adult patient received blood ...
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0answers
17 views

Mechanism by which water flows through xylem

I was doing a Cambridge iGCSE past paper when I came across the question: Describe the mechanism by which water flows through the xylem I thought the correct answer would revolve around the ...
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0answers
18 views

Any books/publications about what life was like before antibiotics?

Just wondering. We've been discussing antibiotic resistant bacteria a bit in lecture, and how we're slowly sinking into a pre-antibiotic era again.
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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 ...
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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 ...
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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 ...
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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. ...
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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? ...
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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 ...
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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 ...
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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: ...
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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 ...
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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 $300 \mathrm{units}/\mathrm{ml}$, ...
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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 ...
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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 ...
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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 ...
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0answers
30 views

Genetic tests on S. cerevisiae to determine mutation locus on genes

I am studying the metabolism of galactose in the budding yeast Saccharomyces cerevisiae. After a random mutagenesis screen, several mutant strains were isolated that grow well in glucose but are ...
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0answers
32 views

Why do Sorghum Bicolor leaves roll up?

In A level Bio today we talked about abcesic acid as a stress hormone, and its ability to reduce osmotic potential around guard cells to close stomata. My question is, is abscesic acid in sorghum ...
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0answers
30 views

recombinant gametes

Suppose you are able to observe under a microscope the total number of meiotic divisions occurring in one gonad of a given individual and to outnumber exactly the crossovers between two given ...
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51 views

Paired-end mapping exercise

Pair-end mapping (PEM) is a technique that allows to detect structural variants in DNA by obtaining paired-end reads and the comparison of their positions in a reference genome. Then among libraries ...
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0answers
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Interpreting graph of mitosis and meiosis

Note : Consider the y axis as 1,2,3,4(not 2,3,4) and x axis as time. Roman numerals should be considered from I-X ( some are not correct here ) Which stages show mitosis? My answer : III-V Which ...
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0answers
49 views

What are the characteristic structures of bacillus M. tuberculosis and what they cause?

I answered to this question: In most forms of the disease, the bacillus M. tuberculosis spreads slowly and widely in the lungs, causing the formation of hard nodules (tubercles) in the ...
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0answers
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How were CDK1 and cyclin B identified?

I know that MPK is a dimer containing cyclin B and cdk1 and this promotes entry into mitosis. The experiment I have found was that when MPFs were micro-injected into frog oocytes arrested in G2, the ...
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0answers
16 views

If spore possesses 10 chromosomes with 20 picogram DNA then calculate the amount of DNA in prophase II?

Options : a) 20 b) 10 c) 40 According to me, it should be 20 because a cell in prophase II is haploid after completing meiosis I reduction division. Also, spores are haploid, so amount of DNA should ...
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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 ...
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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 ...
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0answers
42 views

How do cell organelles maintain their unique membrane composition?

Describe some of the ways that membranous organelles can maintain their unique compositions despite the continuous traffic of membranes and materials moving through them. This question is from Gerald ...