This tag indicates that the question is likely based on a home assignment in biology-related university or high school courses. Please see the homework policy on meta before asking homework questions.

learn more… | top users | synonyms

3
votes
2answers
1k 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
2answers
4k views

How do trees use Adhesion and Cohesion to move water against gravity?

I have an AP Bio class where I have to name 3 properties of water and I chose adhesion and cohesion for one of them. I'm having trouble finding out how exactly trees use adhesion and cohesion to move ...
2
votes
1answer
79 views

Regarding kidney transplant

One of the options is correct Kidney can be taken from a dying person who has the a) cessation of neurological function only b) cessation of cardiac function only c) cessation of ...
2
votes
1answer
170 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 ...
2
votes
4answers
107 views

Translation of mRNA?

We inserted an insulin gene from human into bacteria. Will translation of the gene (protein formation) occur in bacteria? If translation occurs then why does it occurs, give a reason for this?
2
votes
1answer
151 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 ...
2
votes
2answers
103 views

Will climate change affect flower population?

There is a flower population elevated 1000 meters above sea level. If climate change causes a 12⁰C increase in temperature over the next 10 years, what will happen to the flowers?
2
votes
3answers
54 views

Use of salt as preservative

I know that salt is used as preservative as it dehydrates microbes. Is there any other advantage like - altering pH or inactivating microbial enzymes ?
2
votes
2answers
1k 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 ...
2
votes
1answer
91 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
271 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
431 views

Is Aspergillus clavatus an unicellular organism?

I could not find the piece of information form Burton Human Parasitology -book and not by Google. Yeast is divided to two phylums: one of them is Ascomycota. Aspergillus clavatus belong to the given ...
2
votes
1answer
94 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
votes
2answers
2k views

What is the Giemsa staining of chromosomes?

I got the question in my exam and wrote the following and I do not understand what is wrong in it: Giemsa staining is a staining method to stain particularly malaria and other parasital diseases. ...
2
votes
1answer
75 views

Substrates of cytochemical reactions in this immunostaining

Expression of extracellular protein Laminin 9 alpha-4 chain in human skeletal muscle. Indirect immunostaining with HRP immunostain marker. Ob.x40. I have unsuccessfully searched NCBI -database, JSTOR ...
2
votes
2answers
96 views

are the spontaneous generation and evolution the same idea but in a different time scale?

I was in my biology class, learning the history of spontaneous generation and how this idea was discarded. I told my teacher that is the same as evolution but in a different timeline. I Argue that ...
2
votes
1answer
95 views

Which process is needed to complete male reproductive development?

In order to properly complete male reproductive development: ...
2
votes
2answers
193 views

Promoter in the lac operon

Here is the question: Suppose an experimenter becomes proficient with a technique that allows her to move DNA sequences within a prokaryotic genome. If she moves the promoter for the lac operon to ...
2
votes
1answer
48 views

Evolutionary conservativeness

List the following proteins in the order of decreasing evolutionary conservativeness of their primary structure: Somatotropin. Catalytic subunit of a DNA – polymerase. Histone H1. ...
2
votes
2answers
225 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.
2
votes
1answer
207 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 ...
2
votes
1answer
27 views

Osmoregulatory Acclimatization in amphibians

If a frog is gradually exposed to increasing concentration of salts can they acclimatise or will they die of exosmosis ?
2
votes
1answer
42 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 ...
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 ...
2
votes
1answer
287 views

What is the structure and function of chromosomes during interphase?

Ok, it seems to be easy but I have probably ignored something by accident. Interphase is the phase where things are growing and the preparation for cell division happens. Its stages G1, S and G2. DNA ...
2
votes
1answer
49 views

Lytic Viruses — Cell lysis?

So in the video my instructor sent on viruses, he said that for lytic viruses, new viruses manufactured by the host cell could get out of the cell in one of two ways. The new viruses would leave by ...
2
votes
2answers
134 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
votes
1answer
31 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 ...
2
votes
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
votes
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
76 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?
2
votes
1answer
223 views

Are Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70 positively charged or negatively charged? [closed]

Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70,are they positively charged or negatively charged ? And which other solvents can be used as a substitute to water for preparing solutions in each ...
2
votes
1answer
241 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 ...
2
votes
1answer
33 views

What are the criteria for determining the origin and end of muscle anatomically?

For example the pectoralis muscle starts from sternum region and ends on the acromion or coracoid process. Why you can't say that it starts acromion process and ends on the sternum?
2
votes
1answer
35 views

Drosophila grey / yellow

I am studying biology by myself via distance-learning. I have been trying to solve the following problem for a while now and hoped you could help me. As this is "homework" I would appreciate hints ...
2
votes
1answer
18 views

Question regarding 2 constructs of tobacco plant

Six independent transformation experiments of tobacco leaf explants were carried out using two different constructs - (1) construct I containing only a Hygromycin-resistance gene $(HYG^R)$ as a ...
2
votes
1answer
56 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, ...
2
votes
1answer
29 views

Neuroscience: zapping an axon connected to thermoreceptor

Let’s say an experimenter has an electrode that can give a shock to a single axon. She takes that electrode and zaps an axon connected to thermoreceptors in the hand of her subject. I) What would the ...
2
votes
2answers
61 views

Maintaining purebred pedigrees and how to lessen chance of getting disease?

Many breeds of dogs are known for a high incidence of genetic disorders. German shepherd and Saint Bernard dogs are predisposed to developing a crippling condition called hip dysplasia. Q: What ...
2
votes
1answer
79 views

Why Can Varied Species Live Together in Particular Ecosystems?

Consider the following question: The Piney Woods of Eastern Texas is home to a wide variety of organisms ranging from the grass Longleaf Oats to coyotes. Which of the following best explains why ...
2
votes
1answer
38 views

Hibernation in ectotherm and endotherm

Both snake and weasel hibernate. Which of the following is correct? A. They will die when temperature decreases below the critical temperature. B. Weasel will die when temperature ...
2
votes
1answer
72 views

Determining sequence of oligoribonucleotide

Oligoribonucleotide X was treated with phosphatase (for removal of 3' and 5' - terminal phosphates), then with RNAase T1, which cleaves all phosphodiester bonds located in a 3' position of ...
2
votes
1answer
73 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 ...
2
votes
1answer
138 views

Why are Birds and Reptiles with abundant yolk sac polyspermic?

I was given an explanation that birds and reptiles are polyspermic because they have an abundant yolk sac. But how does it explain the thing? Chicken as an adult is not using in my opinion yolk as an ...
2
votes
0answers
56 views

How many proteins are synthesized in human body throughout life?

My idea to calculate this is: Define up to what age will do the calculation. (for instance 60) Determine how many cells born and died up to that point in life. (by type of cell) Determine how many ...
2
votes
1answer
32 views

What can thrombosis lead to?

I am thinking this question. Thrombosis can result in organisation of thrombus, sepsis thromboembolism, fibrinoid swelling adiposity. I fibrinoid swelling (edema) (4) can occur. Also, I think (3) ...
2
votes
0answers
39 views

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

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 ...
2
votes
1answer
110 views

Genetics problem-Height of a plant

An inbred strain of plants has a mean height of 24cm. A second strain of the same species also has a mean height of 24cm. When these plants are crossed the F1 are also 24cm in height.However, when the ...
2
votes
0answers
29 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 ...
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). ...