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2
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2answers
30 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
votes
1answer
21 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 ...
2
votes
1answer
52 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
45 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 ...
0
votes
1answer
26 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} ...
0
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2answers
31 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
votes
0answers
23 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
votes
1answer
56 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
51 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 ...
5
votes
1answer
50 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 ...
3
votes
1answer
51 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 ...
1
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0answers
47 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 ...
0
votes
2answers
22 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 ...
6
votes
3answers
2k views

Why do we squint when tasting very sour things?

Sometimes while tasting a very sour thing (like tamarind, lemon etc.) our eyes squint immediately and involuntarily for a second, but a little later becomes normal again. Why, and how, does this ...
2
votes
0answers
23 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 ...
7
votes
3answers
4k views

What are the advantages and disadvantages of using beta-galactosidase compared to luciferase as a reporter gene?

In the University labs, we have used Beta-galactosidase as a reporter gene to quantify the expression initiated by the stress-response promoter in yeast. This was done by exposing one of the two ...
4
votes
1answer
47 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
32 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
86 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
75 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
vote
1answer
17 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
2answers
135 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 ...
2
votes
1answer
62 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
72 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 ...
4
votes
1answer
11k views

Pedigree Probability of Autosomal Recessive Trait

Here is a pedigree: The trait is autosomal recessive. The question is: What is the probability that the bottom 2 people (4 and 5) have a child with the trait? I tried doing ...
0
votes
1answer
19 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. ...
5
votes
2answers
2k views

Diffusion of Hypotonic solution into solution with glucose and starch

Cell walls are selectively permeable to ions and organic molecules. Sometimes the selectivity is passive and a reflection of the physical laws governing diffusion. We can do simple experiments that ...
7
votes
3answers
17k views

Does Human Female Meiosis II occur after fertilization with sperm?

I am reading the answer and I am getting confused by the sentence: At the end of meiosis I females have two daughter cells and meiosis II only occurs if and when fertilization occurs by a sperm ...
2
votes
2answers
127 views

Calcium levels and nerve hyperexcitation

Why does lower blood calcium levels (or lower calcium levels in ECF) cause nervous hyperexcitaton? Why does it cause over stimulation of nerves and muscles and spasmic contractions of muscles? This is ...
1
vote
1answer
88 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. ...
2
votes
3answers
133 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
votes
2answers
118 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 ...
0
votes
1answer
56 views

Hypothalamic breakdown and effect of temperature on membrane lipids

I'm in my last year of high school and doing a research assignment on thermoregulation. In the excellence level exemplar for the standard, a student made the statement: Once the body's internal ...
3
votes
1answer
53 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 ...
0
votes
1answer
105 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 ...
1
vote
1answer
55 views

What is meant by “genes involved in the stress response”?

I would like to know about the term stress response. For example "some genes of a species under study is involved in stress response". What does that mean? I got this as a part of my assignment ...
1
vote
1answer
30 views

Amphibian blood circulation

In an amphibian blood entering the right atrium shows higher levels of oxygenation than that in left atrium when : A.It is hyperactivated B.it is hibernating C.it is submerged D.it is in the ...
0
votes
1answer
31 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
25 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 ...
1
vote
1answer
156 views

Energy flow in an ecosystem

What are the mistakes in here? The image below shows a part of the energy flow diagram in an ecosystem. 1. Part P of the biomass of the primary producers does not get consumed. Give a concrete ...
1
vote
1answer
523 views

Amino acid characteristics that determine their chemical properties?

What chemical aspect of amino acids results in their having different properties such that the chemical and physical properties of polypeptides vary with both amino acid content and amino acid order? ...
3
votes
1answer
74 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 ...
2
votes
1answer
101 views

Mouse meta-globin mRNA problem

This is an mRNA strand of mouse meta-globin: 5'-ccccagauacggaauucgaau-3' A) Which small RNA (below) is most likely to regulate expression of meta-globin? ...
0
votes
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 ...
5
votes
1answer
138 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 ...
1
vote
0answers
17 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 ...
1
vote
1answer
106 views

Interpretation of graph from evolutionary biology

I am studying evolutionary biology, and been presented with this graph: I am having some difficulties understand its meaning. For a start, why is time measured as a fraction of the population size? ...
0
votes
1answer
259 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
votes
1answer
70 views

Question about what the liver does NOT do

Which of the following functions is NOT performed by the liver? a) Storage of vitamins and minerals b) converts glucose to glycogen c) converts toxins to harmless chemicals d) produces bile I chose ...
4
votes
1answer
3k views

What are differences between formation of embryonic disc in chick and mammal embryo?

Exam question which got lowest average points in my university: 1/5 average. No markscheme available so my attempt below. I assume that embryonic disk prefers to germ disk such that Formation prefers ...