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1answer
43 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
27 views

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

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

What are the significances of chromosome mapping? [on hold]

The few point that I have come across are: The following are the significances of chromosome mapping: Chromosome maps help identify the location of gene of interest on a chromosome for genetic ...
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0answers
21 views

Seasonal and Ecological colours [on hold]

Is the following correct? Difference between ecological colour and seasonal colour: Ecological colour It is the colour that remain throught the year and does not change with season. e.g.- Cryptic ...
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1answer
154 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 ...
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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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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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0answers
16 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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1answer
34 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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0answers
41 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 ...
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1answer
25 views

What are the binding sites (or receptors) of cortisol?

I am in the process of a OCR GCSE Case Study, and my question is "Do the benefits of anabolic steroids outweigh the risks, which has an obvious conclusion. I need to know the scientific name, or a ...
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0answers
9 views

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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1answer
16 views

When do 3 germ layers form in embryo? And why is there only one mature egg formed?

During the process of pregnancy, when do the 3 germ layers form in embryo? Is it after formation of gastrula? Also, during oogenesis, why does only one mature egg form? Why don't use polar body egg ...
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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
60 views

Why don't membrane proteins move?

I understand that based on their tertiary structure, intrinsic proteins have hydrophobic non-polar R-groups on their surface and that they 'interact with the hydrophobic core of the cell membrane to ...
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2answers
99 views

Which of the following lacks DNA?

a) An Enucleated ovum b) Mature RBC c) A mature spermatozoan d) Hair root According to me, there can be 2 answers, a and b because an ovum whose nucleus has been removed lacks DNA. And also, ...
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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? ...
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2answers
24k views

What factors affect the rate of transpiration in plant leaves?

I'm trying to get my head around factors which affect transpiration in leaves. For example, how would applying petroleum jelly to the surface of plant leaves affect their rate of transpiration? I ...
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0answers
57 views

What is the Ramachandran z-score of a denatured protein?

I thought it should be 0, but the professor pointed out I was wrong. What should the Ramachandran z-score of a denatured protein be?
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0answers
32 views

Rate of diffusion [closed]

I need to find out the intial diffusion rate across membrane. I know the formula of J=DA(C1-C2) but i am confused about how to make the calculations I also know the following: 1) Na+ concentrations ...
1
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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 ...
2
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0answers
78 views

How does the introduction of clones would affect population genetics? [closed]

Since the ability to clone animals gives another way to preserve species, this could help for the breeding process. It has been noted that with the ability to clone animals, endangered species can ...
1
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0answers
17 views

DNA. mRNA, tRNA [closed]

Can someone explain to me how transcription and translation works, especially the part about codes. And does amino acids has code or is it the tRNA?
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1answer
41 views

A state model of sodium channels

I am studying by myself Human Physiology. I have encountered the following question: In the following given model of sodium channel with 3 states open closed blocked (which I assume means ...
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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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2answers
64 views

What animal produces male gametes by mitosis?

The following question came up in my biology examination but I could not answer it: "What animal produces male gametes by mitosis?" I know that some plants produce their gametes by mitosis in ...
5
votes
1answer
102 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 ...
29
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2answers
8k views

Who are humans' closest relatives, after primates?

This question here addresses the controversy of whether humans are more closely related to bonobos or chimps. My question is - which group of animals are are closest relatives, beyond primates? Or ...
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2answers
44 views

Choice of primers for PCR

This exercise was given by my professor but I am struggling to understand the solution. A PCR is performed on the following sequence (in order to replicate the chain and thus have a greater quantity ...
4
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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 ...
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1answer
54 views

Data on Gene Position in Human Genome

I am trying to get some data on gene position in the human genome and I need some help What I tried I downloaded ...
2
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1answer
52 views

How many paraphyletic groups can be formed from a phylogeny?

How many paraphyletic groups can theoretically be created from this phylogeny? I found (2n)-2. Is this correct? This is not homework nor exam, just a question about paraphyletic groups.
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1answer
67 views

Based on this diagram, how do you deduce the keystone species? [closed]

How would you figure out what the keystone species is in the following textbook question? (questions 1 and 2 at the bottom of the image) Based on my knowledge, a keystone species helps to maintain ...
1
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1answer
52 views

Why all trees have cylindrical stems?

Why a huge number of trees/plants have cylindrical stems? I have been told that this question's answer lies in Physics but I don't know where to find. Can any one help?
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0answers
23 views

Why is CO2 unable to be catabolized by cell? [closed]

Why is CO2 unable to be catabolized further ? a.The double bond in CO2 is too strong b.CO2 has less bound electron than any other organic compound c.CO2 has been fully reduced d.CO2 has been fully ...
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1answer
58 views

What cause the urge to inhale in humans? [closed]

The urge to inhale in humans result from (a) rising pCO2 (b) rising pO2 (c) falling pCO2 (d) falling pO2 p stands for partial pressures. I am guessing the answer is falling pCO2.... but I wanted what ...
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0answers
58 views

Why do gram-positive bacteria cause respiratory diseases more frequently than gram-negative bacteria? [closed]

My theory is that aerobic respiration by gram positive bacteria thrives in ideal conditions of the lungs therefore creates respiratory diseases?
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0answers
20 views

Electrophoretogram of microstallites - DNA profile of children [closed]

This exercise says that Paul and Caroline want to have 2 children. The question is: what is the probability that the 2 children will have the exact same DNA profile at those 4 loci? Then the given ...
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2answers
33 views

Are intercellular junctions, synapses and light-capturing photosynthetic complexes mobile? [duplicate]

I was reading Cell Biology by Gerald Karp and came across a section which said- Membrane fluidity makes it possible for clusters of membrane proteins to assemble at particular sites within the ...
3
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1answer
61 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: ...
5
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2answers
5k views

How do we know that everybody's DNA fingerprint is unique?

How do we know that everybody's DNA fingerprint is unique? I know, I know, everybody's DNA is unique. But when we do DNA fingerprinting, we're looking at very specific regions of high variability. ...
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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.
3
votes
1answer
84 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 ...
3
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0answers
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
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 ...
3
votes
1answer
69 views

spinal cord lesion and result in somatic sensation

Jimbo suffers a lesion to the entire right half of the spinal cord at the T6 level. A few weeks after his injury, his doctor tests his right and left legs for somatic sensation and tone. fill out her ...
3
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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 ...
1
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1answer
96 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 ...
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0answers
41 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 ...
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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.