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X-linked Traits in Males and Their Effect

Let's say you're a male and you're hemizygous for an x-linked recessive trait (i.e. Haemophilia), will you express that trait? A question from my textbook can be paraphrased as follows, Tom and ...
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1answer
35 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
56 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
25 views

How to recognise the type of allele by pedigree analysis diagrams?

It was said that this interference pattern is due to dominant allele. I fail to see that. In general how to recognise the type of allele by pedigree analysis diagrams?
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0answers
14 views

No.of codons at A-site [closed]

If a protein consist of 20 Amino acids. The number of codons exposed at A-site of ribosomes will be: A) 20 C) 21 C) 22 D) 19
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0answers
27 views

What is the name of the method used for solving the problem?

Problem: A Drosphila sp. heterozygous female of the X-linked recessive traits encoded by alleles a,b and c is crossed with a male that is phenotypically a,b and c. If offprings occur in the ...
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0answers
43 views

Need Help on a Biology Question about Pedigrees [closed]

I was given a biology question that says: "Which of the following pedigrees could occur if the shaded individuals show an X-linked dominant trait and partially shaded individuals are unaffected ...
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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. ...
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5answers
648 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?
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1answer
91 views

Does this patient have HHV6 or HCMV after transplant surgery?

I have been given mock results from a PCR test on blood samples taken from kidney recipient patients and their donors. The PCR reaction can detect single copies of viral DNA. I have been asked to ...
3
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2answers
171 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? ...
0
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1answer
24 views

calculate elimination rate constant [duplicate]

A patient diagnosed with cancer takes antiproliferative drugs. Suppose the intake of drug(dose) is 250mg and excreted amount 125 mg. Amount of excreted drug as metabolites 1 and 2 are 75mg and 50mg. ...
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1answer
77 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
78 views

What is the transcriptome in layman's term?

I am new to the bioinformatics field and am trying to understand a research paper that includes some terminology without definitions. The term transcriptome in particular is banded around in the ...
1
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1answer
28 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 ...
4
votes
1answer
64 views

Why is the Pentose Phosphate Pathway so active in erythrocytes?

Is it because glyceraldehyde -3-phosphate (a molecule which when enter glycolysis help produce ATP through substrate level phosphorylation) can be prepared without losing an ATP through this process?
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1answer
79 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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3answers
110 views

What is the actual storage form of energy in muscles? ATP or Glycogen?

I was asked this question in my latest exam. I think the answer is Glycogen because ATP doesn't store energy for a long time so it isn't the ACTUAL storage of energy. Some classmates argue that in ...
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3answers
75 views

Doubt in a multiple choice question involving cell organelles

Find the odd one out and state the category of the rest. Chloroplast Mitochondria Nucleus Grana Now my answers are : 1st possibility : grana Category : presence of DNA in ...
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1answer
82 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 ...
2
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0answers
31 views

Can the respiratory quotient be calculated from a formula or must it be measured directly?

I found the following question on the Respiratory quotient: A normal human diet has a Respiratory quotient (RQ) of approximately 0.85. Given that pure oxidation of fatty acids has a Respiratory ...
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1answer
31 views

What is the relationship between independent assortment and cross over?

During meiosis, the independent assortment will be made first and then cross over will be made. I am so confused, what is the difference between this two process? I looked at the diagram on internet....
3
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1answer
85 views

How likely is it that a person's progeny has an inheritable disorder based on this pedigree?

Case study: A person (let's just call him "John") had 3 aunts that died back in the 1950's in early childhood due to an unknown form of neuromuscular disorder. One died at birth, one at 2 years and ...
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2answers
45 views

doubt with a multiple choice question [closed]

Permanent decrease in population would occur due to- A) Migration B) Natality C) Emigration D) Mortality E) Territoriality . It's obvious that C) & D) options are possible . But I'm confused ...
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2answers
127 views

Hamilton's Rule in practice

I came across this question in USABO 2013 open exam: A mother antelope and its child are galloping along the plains, when they encounter a group of hungry lions. If the two antelopes try to escape ...
3
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1answer
29 views

How many cell membranes are oxygen and carbon dioxide diffuse through in the lungs?

In the lungs, oxygen and carbon dioxide pass through cell membranes by diffusion. Which row is correct? The correct answer is D, but I think it should be B. I can only think about three layers as ...
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1answer
22 views

Which diagram correctly describe an effect of tar entering lungs?

Which flow diagram correctly describes the effect of tar entering lungs? Tar is a cause of Chronic obstructive pulmonary disease (COPD) which includes both chronic bronchitis and emphysema and it ...
0
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1answer
54 views

Photosynthesis and its subtopics [closed]

Which of the following statements about photosynthesis is true? a. Photosynthesis is an energy consuming process b. The light-dependent reactions produce the energy-rich compounds that are used up ...
3
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0answers
38 views

How is a T lymphocyte specific to an antigen but not specific to an epitope?

In my immunology notes, it states that B lymphocytes (and other APCs) capture and present antigens to T lymphocytes that is specific for an antigen, but that the T cells do not necessarily recognise ...
6
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2answers
136 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, ...
2
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1answer
49 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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votes
2answers
107 views

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 sex-...
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1answer
20 views

distribution of some injected materials/medicines through blood vessels [closed]

Fastest distribution of some injected materials/medicines & with no risk of any kind can be achieved by injecting it into - artery or vein?
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1answer
43 views

What are silent carrier traits? [closed]

I couldn't find a definition but I have come to know the following from google search: People who are carriers of a thalassemia gene show no thalassemia symptoms and might not know they're ...
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1answer
38 views

What is the difference between “genetic” and “hereditary”? [closed]

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

What are the significances of chromosome mapping? [closed]

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 ...
2
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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
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1answer
28 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
11 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 ...
0
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1answer
25 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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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 ...
2
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0answers
84 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 ...
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0answers
22 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?
0
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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 inactivated)...
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0answers
18 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 ...
2
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2answers
77 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 ...
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 ...
29
votes
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
49 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
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 ...