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Homework Question: Confused about figure related to cDNA and gDNA

what is the answer in blank? I think the loop structure for the top blank is an intron. I think RNA is the answer for the bottom blank, but it is cDNA, so it can't be RNA. I cannot figure out what ...
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1answer
114 views

What is enantiostasis?

I have searched around and read my textbook but I am failing to understand how enantiostasis is different to homeostasis. For reference, Wikipedia definition is as follows: Enantiostasis is the ...
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2answers
115 views

How to use swiss-mod to predict the secondary structure and 3D structure of a protein?

I'm trying to predict the protein secondary and 3-D structure for the sequence [Q1NN20] and need some help getting the ball rolling. I'm getting confused with how and when to use Jpred, swiss-mod, ...
3
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1answer
224 views

How to perform a DNA structural alignment in pymol

How can I "fit" two DNA structures having different nucleotide sequences in pymol? I would like to use the structure of a DNA binding protein in pdb (1h9t), which is bound to DNA in the pdb file, ...
2
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1answer
1k views

recombination frequency problem

Three loci C, D and E are located on the same chromosome in this order. We found that the frequency of recombinants between C and D is 10% and that between D and E it is 20%. Assuming that ...
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1answer
2k 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 600-...
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0answers
56 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 ...
0
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1answer
685 views

Possible Genotypes — Linked Genes

Please consider the following question: Genes A and B are located on the same chromosome. If two individuals with the genotype shown below are crossed, which genotype could be formed? Let / ...
2
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0answers
29 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 better ...
1
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1answer
130 views

Disadvantage of using Drosophila for breeding experiment

What should be the disadvantage of using Drosophila for experiments? a)small size of larva. b)short life cycle. c)mating soon after emergence of flies. d)large number of offsprings. Options (b) and ...
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2answers
147 views

Non-ribosomal peptide synthesis: why Glutathione cannot be produced by the ribosome?

Case: I am writing a summary for a class in protein structure and function, and was asked to describe some different ways that peptides are synthesized (that does not involve the ribosome). I ...
3
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1answer
68 views

Why do some bacteria have an asymmetric replication?

Our teacher said that Bacillus subtilis has an asymmetrical replication fork. I know that this happens only in some strain of the bacteria . She asked us to find an explication for this mechanism , ...
1
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1answer
60 views

tandem repeat sequence; causes of contraction and/or expansion question

Question: Which of the following events, occurring within a tandem repeat sequence, will cause an expansion or contraction of the array? A) Endoduplication B) homologous recombination C) ...
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0answers
120 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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0answers
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 by ...
0
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1answer
30 views

kinetics question [closed]

An enzyme has a $V_{max}$ of 50 $\mu$mol product formed $(min * \text{mg protein})^{-1}$ and a $K_m$ of 10 $\mu$M for the substrate. When a reaction mixture contains the enzyme and a 5$\mu$M ...
1
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1answer
23 views

Ways to identify that proteins are regulating different genes experimentally

As part of my study I have been given this hypothesis: HIF 1a and HIF 2a regulate different genes in multiple myeloma What ways do we have to identify that these proteins are regulating ...
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0answers
47 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
78 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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2answers
82 views

“structural and regulatory elements of genes” [closed]

Can anyone please explain a little about these two elements of genes? My main problem is with "which ‘switch on’ instructions". genes have structural elements (which code for a particular protein) ...
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0answers
32 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
51 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 ...
3
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2answers
347 views

tetrads in meiosis are held together by what

This is from SAT subject biology test practice question. The answer it gave me was both chiasmata and centromeres. I can understand they are held by chiasmata but why also centromeres? I looked it up, ...
5
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2answers
209 views

Difference between biological control and introducing species for conservation?

I have a biology assignment and we have to explain various methods and strategies for conservation, two of which are: Biological control Introduced Species What is the difference between these?...
3
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1answer
131 views

What is a holocentric chromosome?

I was doing this question that asked: "How many centromeres does a typical chromosome have?" I thought one and the answer was:"One, except for holocentric chromosomes." So then what are "...
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0answers
162 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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1answer
406 views

Hardy-Weinberg Equilibrium Question

I have four questions concerning H-W Equilibrium: (i) In a population of mice, the presence of black spots is the result of a homozygous recessive condition. If the frequency of the allele for this ...
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1answer
92 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 ...
3
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0answers
126 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
142 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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1answer
262 views

Albinism inheritance problem: what are the father's alleles if he got an albino kid?

Albinism is caused by a recessive gen "c". A normal man marries an albino woman. The first son happened to be albino. What are the possible phenotypes of the parents? What is the chance that their ...
5
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1answer
257 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 ...
2
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1answer
49 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
75 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
172 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 ...
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0answers
31 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 ...
4
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1answer
843 views

What happens to the red blood cell in CaCl₂ 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? ...
4
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2answers
2k views

Is secondary follicle or Graafian follicle arrested in the second metaphase of oogenesis?

My note about which I am not sure: Secondary oocyte is arrested in the metaphase II monthly after puberty until fertilization with sperm. The following picture also satisfies my sentence: . So ...
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1answer
73 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: X-...
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2answers
431 views

Hardy Weinberg Equilibrium after 5 Generations

1 There is a population not at HWE where red eye = $a^+$ (dominant) and white eyes = $a^-$. If: $a^+/a^+ = 0.6$ $a^-/a^+ = 0.1$ $a^-/a^- = 0.3$ what are the frequencies of the $a^+$ and $a^-$ ...
2
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1answer
301 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
110 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 ...
4
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1answer
109 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 ...
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2answers
64 views

3 fates of this matter

When an animal eats something, it obtains matter and energy right? But, what are the 3 possible fates of the matter and 3 possible fates energy. I don't understand what they are even asking. What ...
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0answers
36 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
162 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
122 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 ...
3
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0answers
53 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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2answers
143 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
82 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 (...