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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
755 views

Number of reading frames in nucleotide sequence

In class of molecular biology was posed this question: "How many reading frames start in sequence of nucleotides 5' ... ATATGAATGATGACAT... 3' ?"
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1answer
23 views

Order of events in hibernation

Arrange this in sequence : i. Heat loss exceeds heat production. ii.As body temperature falls, heat loss decreases. iii.Body temperature equals environmental temperature. ...
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1answer
23 views

Is ability to easily pollinate desirable?

In Mendel's crosses was it desirable for the plants to be able to cross-pollinate and self pollinate easily ?
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1answer
370 views

Recombination frequency, linked genes, and independent assortment

Gene R is genetically linked to gene T with a recombination frequency of 0.3. Gene T and gene X assort independently from each other. Your colleague tells you that gene T and gene X reside on the same ...
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2answers
160 views

Hardy Weinberg Equilibrium problem

In a small tribal population, the frequencies of two alleles A and a at a particular locus were 0.3 and 0.7, respectively. However, not all the individuals with genotype aa could live up to the ...
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0answers
627 views

Interpreting graph of mitosis and meiosis

Note : Consider the y axis as 1,2,3,4(not 2,3,4) and x axis as time. Roman numerals should be considered from I-X ( some are not correct here ) Which stages show mitosis? My answer : III-V Which ...
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2answers
398 views

Gel electrophoresis question

Leena is a molecular biology student. She purifies two fragments of DNA, 800 and 300 base pairs long. These were obtained from a plasmid after digesting it with HindIII. Each of these fragments has a ...
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2answers
112 views

Protein purification methods

Which of the following methods would yield the most purified protein fraction? A. Salt precipitation B. Charge separation C. Affinity purification The first one is the most commonly used, is it ...
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1answer
79 views

Electrophoretic mobility of isozymes

If isozymes are seperated using electrophoresis, which of the following will be the principle of separation ? A.charge density B.molecular weight C.polarity of molecule I think it should be B.
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2answers
295 views

Homework : Sodium Potassium pump

Why does sodium-potassium pump consume about 2/3 energy of a cell ? A.maintains appropriate membrane potential B.helps in co-transport I think it should be A.
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1answer
53 views

Proportion of amino acids from a random polymer of U and C

A protein synthesis assay was carried out in vitro. A polyribonucleotide containing U and C in proportion 1:5 (positions of U and C are random) was used as a template. Which amino acids and in ...
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2answers
2k views

What is the purpose of measuring both VS (volatile solid) and TS (total solid)?

In the biogas process you often measure Volatile solid and Total solids. Can any one explain these concepts more accurately and why it is interesting to look at these properties. The biogas process ...
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2answers
151 views

Which statement about phenotypic plasticity is false?

This was a test question, and I'm not too sure about the answer. Which statement about phenotypic plasticity is false? a. Because the plasticity of a phenotypic trait may be costly to maintain, it ...
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1answer
273 views

Genetic variation and sensitivity of wild cabbage

1: Is it true that the genetic variation of kale plants is smaller than wild cabbage? I think so, because of human selection of the kale plants. 2: Are broccoli and cauliflower more ...
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0answers
45 views

Shortest route for a Nitrogen atom from fossil fuel to a protein in your body? [closed]

Millions of years ago fossil fuels originated from plants. A nitrogen atom from fossil fuel is now inside in a protein molecule in your body. What is the shortest path that the nitrogen atom ...
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1answer
102 views

Which mountain range was formed first (historically) and which the pedigree is correct?

Source 1: Source 1 shows a map of a particular area. In this map you will find the mountain ranges 1 and 2, the species P, Q and R. Two possible pedigrees of the ancestral history of the species ...
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0answers
67 views

Why did the yeast rise?

Here are the notes I made for an experiment I was doing (I didn't put it here as it is too long) (please ignore the numbers at the end of the pdf file) The graph looks like this: As you see on ...
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1answer
71 views

Function of carapace

Majority of crustacean larvae have expanded carapace drawn out into processes as an adaptation for : a. Protection from enemies b. Planktonic habit The answer given is b but I think it should be ...
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1answer
289 views

Population Growth Rate Question?

A population of 600 birds faced a problem of biological magnification resulting in a large number of deaths reducing their population to 350. But 230 births also took place and 21 birds immigrated ...
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1answer
45 views

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
49 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
107 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
56 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
324 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
134 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
44 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 ...
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1answer
148 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
58 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
317 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
135 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
37 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
38 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
56 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 ...
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1answer
40 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 ...
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0answers
37 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 ...
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1answer
128 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
50 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
4k 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 ...
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1answer
104 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 ...
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1answer
79 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
159 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
127 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
65 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
400 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
186 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 ...
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1answer
194 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 ...
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1answer
124 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
241 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 ...