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1answer
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Reassociation of DNA

What is the order in which this DNA samples would would reassociate ? e.coli DNA plasmid DNA viral DNA satellite DNA DNA-RNA hybrid This is a homework question and I have not been given any ...
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1answer
44 views

How can a respiratory infection lead to a skin infection?

Example of a case: 5 children develop a bright red rash on the face and turns violet after a few days and then disappears. Then maculopapular rash appears on the trunk, buttocks and extremities. It ...
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1answer
95 views

Lizards are sometimes called cold-blooded because they depend on their surrounding temperatures to keep them warm.

Predict how the composition of the cell membrane of a lizard might change from winter to summer. Justify predictions. Can someone please help me figure this out. Does it have to do with fluidity?
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1answer
55 views

Male behaviour during breeding season

The mountain blue bird build nests to attract females and exhibit aggression towards other males during breeding season. Which of the following is likely to give the birds maximal evolutionary ...
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1answer
250 views

Possible Genotypes of 4 Alleles of Adh

There are four alleles of Adh which are Adh-1, Adh-2, Adh-3 and Adh-4. Their respective frequencies are 0.11, 0.84, 0.01 and 0.04. What are the Hardy-Weinberg frequencies of the possible 10 ...
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1answer
106 views

Which is the correct statement on proteins?

I need help with one of the questions on my biochemistry assignment Choose the correct statement on proteins: a) proteins are folded by alpha-helix b) proteins can preserve their function even if ...
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2answers
50 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
38 views

What are the characteristic structures of bacillus M. tuberculosis and what they cause?

I answered to this question: In most forms of the disease, the bacillus M. tuberculosis spreads slowly and widely in the lungs, causing the formation of hard nodules (tubercles) in the ...
3
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1answer
124 views

Why are centrioles aligned at 90 degree with each other?

The centrioles are aligned at 90 degree with each other. What is the function of this?
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1answer
57 views

Which fish will have more developed gills?

A fish lives at the depth of 1000-2000m and another at the depth of 200-700m. Which of them would have a more developed gill system ?
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2answers
241 views

Factor causing Methicilin-resistance in MRSA?

I think the main reason is the natural selection that is causing methicillin-resistance. However, I am not completely sure what this means practically. Here, the original question: MRSA was isolated ...
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1answer
104 views

Is this case Histoplasma capsulatum?

A 62­ year-­old male was admitted to the hospital complaining of shortness of breath. His chest X­-ray showed a rightsided cavitary lesions. His medical history indicated he had smoked one pack of ...
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1answer
33 views

Which strains of C. diphteria are causing Diphteria toxin?

I got this question: Diphteria toxin is produced only by those strains of C. diphtheria that have which of the following characteristics? Encapsulated glucose fermenters lysogenic for b-prophage ...
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1answer
35 views

How to Diagnose this hepatitis A, B and C case?

Male patient who is working in the hospital and may be infected with contaminated blood had hepatitis with genome IA 5 years ago. His hepatitis A at that time was confirmed with the rise of anti.HAV ...
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2answers
53 views

Is this necrotizing skin infection caused by Staphylococcus aureus?

A 5-year-old boy returns from summer camp with several minor cuts and abrasions on legs. He has fever and extensive cellulitis, subcutaneous tissue and muscles are involved. Necrotic tissues were ...
0
votes
1answer
38 views

Can acid-fast M. tubercolosis obstruct alveoli?

I am not sure which word is the best here for colonisation of alveoli by acid fast-mycobacteria. I found this question, and I am getting confused by the term obstruction of alveoli because I tend to ...
2
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0answers
32 views

Elevated transaminases after blood transfusion?

This sparks HCV immediately in my mind. However, there may be other possibilities too. What can you deduce from elevated transaminases if you only know that the healthy adult patient received blood ...
0
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1answer
106 views

Why do bats huddle during late fall?

In the late fall, bats hibernate in clusters with many bats pressed together and holding on to one another. Which of the following supposed advantages of huddling behavior is, in reality, not true? ...
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1answer
45 views

Genetics - Is this hybridization possible?

Suppose you hybridize two plants - One has a red flower and a long stalk, the other has a pink flower and a short stalk. This resulted in these 4 type of plants, with ratio 1:1:1:1 Long stalk red ...
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2answers
2k views

What is genomic imprinting?

What is a genomic imprint? How does genomic imprinting take place? If I say that "this" allele is maternally imprinted does it mean that the allele of the gene is passed only by the mother? If a ...
2
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1answer
97 views

Which cells will pass cancer to offspring?

Each of these types below contains a DNA mutation. Which type(s) will affect the children of the individual whose cell it is. Red blood cell T cell Skin (epithelial) cell Neuron from the brain Sperm ...
2
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1answer
74 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 ...
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2answers
144 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 ...
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1answer
120 views

Single Nucleotide Polymorphisms and diseases

I am writing a report on how Single Nucleotide Polymorphisms occurring in each of these regions: Transcription factor (TF) binding sites Epigentic signals Splicing variants MicroRNA binding sites ...
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1answer
63 views

Breaking of fats

There is a question I encountered. Why is fat harder to digest ? A) It has ester bonds. B) It is not easily soluble in water. Which is the most appropriate answer?
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3answers
359 views

Diffusion across cell membranes

I got this question and don't really understand the difference between the answers. Diffusion is (in cell membrane): a) passive by nature, no metabolic energy is needed b) driven process by ...
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2answers
172 views

Recent and good quality articles on systems biology [closed]

I'm a biotechnology student and I have to write a sort of non-experimental thesis (30 pages long) within the end of a three years study. I'm very interested in the "systems biology" field and I'm ...
2
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1answer
175 views

Two brown-haired people have two children, P and Q. P has blond hair. Q has brown hair. What is the probability that Q is heterozygous?

Two brown-haired people have two children, P and Q. P has blond hair. We therefore believe that each parent is heterozygous and that blond hair is a recessive trait. Q has brown hair. What is the ...
0
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1answer
118 views

How to classify equilibrium points [closed]

I have the two differential equations: $$\frac{dN_1}{dt} = N_1(2 - N_1 - 2N_2)$$ $$\frac{dN_2}{dt} = N_2(3 - N_2 - 3N_1).$$ I worked out the equilibrium points to be at $N_1 = 0, \frac{4}{5}$ and ...
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2answers
209 views

Deterministic model of lambda-phage lysis/lysogeny [MATLAB] [closed]

Project 1 Base: Can someone please help me understand what I need from Project 1 Base code to do questions 1 and 2 from the first image? I'm new to MATLAB so a thorough explanation would be ...
2
votes
1answer
71 views

What causes tree lines?

There is an area of where there is a distinct line of only trees on one side and only shrubs on the other (right next to each other). What could cause this? My attempt: I said there could be a ...
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0answers
51 views

Polymerase Observations [closed]

DNA polymerase I (PolI) contains polymerase, 3'-5' exonuclease, and 5'-3' exonuclease activities in a single polypeptide chain of molecular weight 109 kDa. If E. coli Pol I is exposed to the protease ...
6
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1answer
433 views

How does Topoisomerase II inhibition affect cancer cells?

Topoisomerase II poisons represent some of the most important and widely prescribed anticancer drugs currently in clinical use. These drugs encompass a diverse group of natural and synthetic ...
4
votes
1answer
62 views

Parsimony (cladistics)

I don't understand how to sum the changes in a phylogenetic tree. Here for example: http://www.med.nyu.edu/rcr/rcr/course/phylo-cladistic.html How do you end up with 8 for the first and 9 for the ...
4
votes
1answer
11k 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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3answers
200 views

What is the optimal frame size for protein secondary structure prediction methods?

The whole question is What is the optimal frame size for the second and third generation protein secondary structure prediction methods? Justify your answer. I remember it has something to do ...
6
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1answer
90 views

What is the total number of rounds of cleavage during mammalian embryonic development?

That for frog is 12, but what about mammalian embryos? I cannot find the exact number anywhere.
2
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1answer
31 views

What range of dose should be used?

This is a dose-response experiment testing a new cancer drug. the darker line represents cancer cells. what range of dose should be used? I think it's 2-4 because this affects cancer cells only. is ...
2
votes
1answer
99 views

At what substrate concentration will an enzyme work at 40% of its maximum rate if its Km = 0.095M?

The question involves the Michaelis-Menten kinetics equation. Here is what I did: I took the Michaelis-Menten equation, replaced v with 0.4Vmax, canceled the Vmaxes (one on each side), and solved ...
2
votes
2answers
300 views

Translate DNA to Protein

Assuming the sequence shown is read left to right, what is the sequence of the protein produced? sequence: 5’-ATGTACTTCCATCTGGAATAG-3’ MY ATTEMPT: I know RNA is synthesized 5 to 3. This is ...
2
votes
1answer
46 views

Similarities Between Cells?

Which of the following are usually identical between a lung cell and a brain cell, from the same person, assuming that they are normal (non-cancerous) cells? Circle your choice(s). ...
1
vote
1answer
5k views

Which enzyme catalyzes transcription and which translation?

My attempt: Transcription - RNA polymerase Translation - aminoacyl tRNA synthetase I know that the ribosome almost runs translation, but I don't think ribosomes are enzymes, which is why I went ...
2
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1answer
77 views

Are there any organisms with larva more advanced than adult form?

Usually adult organisms are more sophisticated than corresponding larva, i. e. frogs, mosquitoes, fish. Are there species where the opposite is true?
3
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1answer
1k 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 ...
1
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1answer
136 views

How to manufacture different sized micelles in nano -scale?

I am trying to answer q5: "How can you manufacture micelles in A) nanometerer -scale B) and in ten nanometer -scale?" My Thinking Observations and some thinking Oil in ...
2
votes
1answer
249 views

What happens to colloidal particles in a liquid medium? And how to stabilize it?

Definition Colloid is a dispresion of small particles of one material in another. Definition 2 (Wikipedia) A colloidal system consists of two separate phases: a ...
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0answers
37 views

How many pandemic H1N1 2009 virus sequences were submitted by the Indian NIV as of May 10, 2010? [closed]

The handout I was following is maddening. It says; "Go to the NCBI home page and select 'All Resources (A-Z)' and choose GenBank. Follow the NCBI Flu Resource link to determine how many pandemic H1N1 ...
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2answers
3k views

Restriction Mapping of Plasmid Assignment

pUWL22 is a circular, double stranded, 10.5 kb plasmid. It contains a gene encoding an enzyme that confers ampicillin resistance in the host bacterium. Cloning into the kpn I and Sst I sites ...
3
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1answer
283 views

Predicting progeny of recessive mutations using recombination

I was asked this question on a test and got it wrong, but I'd like to know how to do it. The answers are shown in the blanks below: You are studying two recessive mutations in the fruit fly D. ...
4
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0answers
45 views

Determine which gene is in the middle complementation [duplicate]

Possible Duplicate: Crossing mutant strains on minimal media problem I'm studying this problem for my genetics final: My Attempt: The answer for part B is met2 and the answer for part C ...