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0answers
19 views

Dominant epistasis problem [on hold]

An inhibitor of pigment production in onion bulb I exhibits dominant epistasis over another locus, the genotype iiRR producing red bulbs and iirr producing yellow bulbs. A pure white strain is crossed ...
2
votes
2answers
61 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
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1answer
24 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 ...
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1answer
41 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
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1answer
51 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 ...
0
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1answer
22 views

Which pair of primers should be used to amplify the ORF in PCR? [closed]

So I want to choose the correct set of pair of primers to amplify the ORF of the gene that corresponds to amino acids in a protein. The start and stop codons are underlined. (I know that these need to ...
2
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0answers
17 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 ...
0
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1answer
22 views

How does the structure of the pancreatic acinar cell relates to its function?

So the pancreatic acinar cell synthesizes, stores and secretes digestive enzyme precursors called zymogens e.g. pepsinogen. The structure of the acinar cell shows that there is an apical and basal ...
4
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1answer
487 views

What happens to the red blood cell in CaClโ‚‚ solution?

Here's the problem: One red blood cell is placed in a hypertonic solution of NaCl, another is placed in a solution of CaCl2 equimolar with the NaCl solution. What would you expect to happen and why? ...
0
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1answer
36 views

X-recessive disorder pedigree confusing me

This is a pedigree of a family in which bleeder disease, an x-recessive disease, is present. I am asked which marker, A or B, the disease is linked to. I've asked about this type of problem before: ...
2
votes
1answer
24 views

Confused with gamete sorting problem

A man has the genotype AaBbCc, in other words he is heterozygous in three uncoupled loci on three different chromosomes. A, B and C are the dominant alleles while a, b and c are the recessive alleles. ...
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1answer
37 views

Pedigree problem and type of inheritance [closed]

Please observe the following pedigree and come up with a conclusion as to which type of inheritance is most likely Now it should be obvious that it's either autosomal dominant or autosomal ...
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0answers
35 views

The Human Menstrual Cycle [duplicate]

1) What happens in the ovary and in the bloodstream that brings about this change in the uterus? 2) Why does the level of FSH decrease and remain at a relatively low level during the luteal phase of ...
1
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1answer
72 views

What can cause a lump in the middle of the neck? (homework case study) [closed]

What can cause an erythematous, fluctuant, nontender mass in the middle of the neck? Full Case Study: (Its the last of 6 cases and I just can't figure this one out, because of all the possibilities, ...
5
votes
1answer
53 views

How do I know which alleles the parents have?

I have the following assignment where I am to look at the "tree" (not sure the english word) and assign whether or not they can be autosomal dominant or recessive as well whether they can be X-linked ...
4
votes
1answer
68 views

Bayes theorem for mutations

MEN 2A is a dominant inherited disease caused by a mutation in the RET proto-oncogene. The probability of being sick when you have the mutation of the RET proto-oncogene varies with age and is assumed ...
3
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0answers
32 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 ...
2
votes
2answers
38 views

Help reading chromatogram

A genetic variation is found in this chromatogram: It says that the "reference sequence" is the top line and that I can use the general genetic code to find the reading frame. I can see that there ...
2
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1answer
26 views

How do I make conclusions from the autoradiograph of a Southern blot?

Here's another question taken from "Concepts of Genetics," Klug et al (10ed), revolving around a paternity test. PCR and a Southern blot were carried out in order to determine whether 3 chimpanzees ...
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1answer
34 views

How to tell if a given gene is a tumor suppressor or oncogene?

This is a problem taken from "Concepts of Genetics", Klug et al, 10e. I'm given the following table about the mutations in the BRCA1 gene: $$\begin{array}{c|c|c|c|c} ...
2
votes
1answer
80 views

How to isolate host cell RNA (tRNA,mRNA,rRNA) from viral RNA?

A retrovirus with RNA genome infected a host cell. You would like to isolate the host cellโ€™s RNA (rRNA, tRNA, and mRNA) from the virus RNA. What properties can you rely on to determine the three types ...
-1
votes
1answer
59 views

What makes a good phylogenetic tree?

How can one improve a phylogenetic tree? If one was to make the 'golden standard' of phylogenetic trees what features would it have? Would it be highly reliable, well resolved etc? What other features ...
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2answers
34 views

Cellular Immunity Response

What response of cellular immunity would appear after complementary protein activation to keep pathogenic bacteria away from our body? Notes: I do appreciate your explanation. Though I am facing ...
3
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0answers
27 views

Blood as newtonian flow and Poiseuille law [closed]

For a prep exam: A healtly pacient has a carotid with the following characteristics: intern ratio: ๐‘…= 2.8 mm, ๐‘ƒ2 = 89 ๐‘š๐‘š๐ป๐‘”, ๐‘ƒ1 = 90 ๐‘š๐‘š๐ป๐‘”, ๐œ‡blood = 3.5 cp, ๐ฟ=10.0 cm. Using the ...
2
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1answer
72 views

Are genotypes with the same two alleles equivalent even if the alleles come from different parents?

I am looking at the following question If $m$ alleles may occur at a given locus, how many distinct diploid genotypes are possible at that locus? The obvious answer is that there their is $m$ ...
3
votes
1answer
66 views

Hardy-Weinberg Color-blind

In a city, 4% of male population have color blindness. How many of the female are (a) color blind carrier, (b) color blind? Suppose the city holds Hardy Weinberg equilibrium. My progress: 4% of male ...
3
votes
1answer
77 views

How is excretion of metabolic wastes from a cell related to its size?

As with anything that is taking place within a cell, the metabolic waste too must be proportional to the size of the cell. In particular the surface area to volume ratio. But how is the waste ...
0
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2answers
24 views

Risk of autosomal dominant disorder [closed]

What can you conclude about the risk (with each pregnancy) that a couple could have a child affected with an autosomal dominant disorder if... One parent is affected (heterozygous) and the other ...
2
votes
0answers
29 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 ...
4
votes
1answer
72 views

DNA sequencing problem

First off, let me start by outlining the problem: Your laboratory has established a technique for examining DNA replication in a cellular extract. To the cellular protein extract, you add ...
3
votes
1answer
45 views

In which of the following diseases structure of haemoglobin produced is normal but their amount reduced?

The options provided are- Chronic blood loss Sickle cell anaemia Haemolytic anaemia Thallasaemia Transfusion reactions - *Q-15: pg-785; **Review of Medical Physiology - William F. ...
4
votes
1answer
140 views

Cellular Respiration/Fermentation Problem Leading to Lack of Energy

A young animal has never had much energy. He is brought to a veterinarian for help and is sent to the animal hospital for some tests. There they discover his mitochondria can use only fatty acids and ...
1
vote
1answer
165 views

How would i describe a Cladogram as paragraph? [closed]

I have this paragraph that i have halfway finished, but i do not know what to put in the spaces. A Cladogram is a branching diagram that represents the proposed phylogeny or evolution of a species ...
1
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1answer
23 views

Using a Sphygmomanometer [closed]

If you were to use an older sphygmomanometer and a stethoscope to record blood pressure, why would you hear no sound when the cuff was inflated to 160mmHg
2
votes
1answer
77 views

Biphasic T wave caused by digitalis toxicity

Digitalis is a drug that can be used during coronary insufficiency to increase the strength of cardiac muscle contraction. But when overdosages of digitalis are given, depolarization duration ...
4
votes
2answers
89 views

What is a triglyceride?

I'm confused on what a triglyceride is, from what my text book it says its a type of gylercide, then from a website it said Glycerides can be subdivided into two categories. The first group, the ...
0
votes
1answer
21 views

How to decide if genes are linked in an unordered mapping problem?

From what I understand, if the tetrads resulting from a cross exhibit the same number of parental ditypes as there are nonparental ditypes, then the genes under consideration are said to be unlinked. ...
2
votes
3answers
212 views

True or false & fill in the blanks

A ribosome is where amino acids are linked together by peptide bonds. A virus is NOT considered prokaryotic because it does not have a membrane. The nucleotide ATP is one of the most used energy ...
3
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2answers
142 views

Assessing probability from a pedigree

This isn't exactly homework but I'd like to treat it as such. I'm asked to find the probability that both (III: 2) and (III: 3) are carriers given that (II: 7) and (III: 1) exhibited the recessive ...
1
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1answer
124 views

How to determine if this blood disorder is recessive or dominant?

This question is from "Concepts of Genetics," Klug & Cummings, 10e. "Thalassemia is an inherited anemic disorder in humans. Affected individuals exhibit either a minor anemia or a major anemia. ...
5
votes
1answer
62 views

Is probability for double crossing over included in distance cM? [task]

We got this task: There are 3 genes (acb) on one chromosome (linked inheritance). Distance a-c = 12cM, a-b=16cM. Probability for double crossing-over (CO) is 0,6%. Find ratio of genotypes of ...
0
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1answer
112 views

Can someone help me analyze this article?

I need to read this article โ€” "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 ...
0
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1answer
35 views

PCR cycle problem [closed]

IF I began a PCR cycle with 5 copies of a particular DNA section, and copied the section by PCR, for 6 cycles, how many copies of the DNA (include the originals) would I have by the end of these ...
0
votes
1answer
26 views

Intro Bio question: dihybrid punnet square

Today we had our exam. There was a punnet square for two genes. and when I multiplied , for example, Ry ร— rY I wrote the answer as ...
2
votes
2answers
155 views

Simple Mendelian Genetics Question

here is my question: In certain plants, tall is dominant to short. If a heterozygous plant is crossed with a homozygous tall plant, what is the probability that the offspring will be short? My ...
3
votes
1answer
81 views

Problem on number of amino acids that an alien can use

A new life form discovered on a distant planet has a genetic code consisting of five unique nucleotides and only one stop codon. If each codon has four bases,what is the maximum number of unique amino ...
5
votes
1answer
240 views

Restriction Mapping - Homework question

I have trouble in solving this exercise. Exercise A circular plasmid of 10,000 base pairs (bp) is digested with two restriction enzymes,A and B, to produce a 3000 bp and a 2000 bp bands when ...
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0answers
21 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 ...
0
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2answers
32 views

T-cells Question

T-cells are important for efficient vaccination since they have: A. T-cell receptor (TCR) B. CD4+ C. CD8+ D. Memory My gut is telling me it's A since the TCR would recognize the antigens but I ...
0
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1answer
422 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 ...