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This tag indicates that the question is likely based on a home assignment in biology-related university or high school courses or is about an elementary concept that may seem trivial to biology professionals. Please see the homework policy on meta before asking homework questions.

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1answer
28 views

How is ligand binding modeled?

I have the following exercise to solve: To be honest, for both parts, my only idea so far would be to divide the rate expression by the sphere area and multiply by the new available areas (that of a ...
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votes
0answers
22 views

Bio calculation [on hold]

You are given a 3 M stock solution of KCl and you are asked to create 15 mls of a 1.7M working solution. What do you do? . Add 1.7 ml of stock to 15 ml of water. b. Add 1.7 ml of stock to 13.3 ml ...
2
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0answers
20 views

Net electrical load of a peptide

I have to determine the electrical charge of the next peptide chain: C - E - H - P I know that this page is not there to raise doubts about this style, but I have looked for resources on the ...
0
votes
1answer
29 views

Why does this genetic pedigree show an autosomal dominant allele at one generation but not another?

Questions 186-188 of the GRE Biology Practice Test are prefaced with this genetic pedigree: Questions 186-188 refer to the following pedigree for the inheritance of a very rare human disease over ...
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0answers
23 views

What change would you expect in phospholipid orientation of the membrane if the enviornment were mostly heptane?

The external and internal environment of the cell is basically water, thus phospholipids organize themselves the way they do (bilayer). If the environment were to magically become mostly heptane, how ...
2
votes
1answer
14 views

Why doesn't oligodendrocyte produce neurilemma

I was searching literature related to neurilemma and oligodendrocyte and came across these lines from WP (Neurilemma) Oligodendrocytes do not have neurilemma because excess cytoplasm is directed ...
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votes
0answers
19 views

movement of ions across a membrane

there is a beaker separated with a membrane that is only permeable to sodium. There are 16 ions on each side, 16 sodium on the right and 16 chloride on the left. What will happen to establish ...
-2
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0answers
45 views

Body compartment

I have read about fluid compartment , understand intracellular fluid compartment and extracellular compartment which has two primary constituents of interstitial fluid and blood plasma. But I did not ...
2
votes
1answer
46 views

Why do proteins targeted for chloroplasts require two signal peptides?

Question #11 of the GRE Biology Practice Test says that proteins targeted for chloroplasts require two signal peptides: Targeting of a newly synthesized protein is most likely to require two ...
-2
votes
1answer
57 views

How to find the amino acid that is bound to a tRNA with the anticodon? [closed]

What amino acid is bound to a tRNA with the following anticodon: $5^{\prime}$ A U G $3^{\prime}$ The answer is Histidine. What amino acid is attached to the tRNA with the ...
2
votes
2answers
56 views

Biological validation of computationally determined gene-gene interaction

How can a computationally determined three-way gene interaction be biologically validated? What kind of assays or tests must be performed using cell/tissue-based and/or mouse models to prove that the ...
3
votes
3answers
72 views

Is it possible to prove that a hand sanitizer can kill 100% of a person's germs?

We have a project for Economics, and we need to advertise something that consumers will be willing to buy. My group thought of "improved" hand sanitizer. So, instead of it killing 99.9% germs, we ...
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0answers
20 views

Is this tree poisonous?

I touched this tree on my visit to South Africa and a huge rash developed on my body,please help,what is the name of this
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0answers
21 views

How to design shRNA?

So I have to design a shRNA and insert it in a vector with on the 5'end a Xhol restriction site and at the 3' end a BglII site. The gene of interest: ...
0
votes
1answer
41 views

If an antiserum was raised in a buffalo by injecting it with monkey red blood cells, what would be the full name for this antiserum?

Im confused, i've attempted this & what i got is buffalo anti-monkey red blood cell antiserum. I'm not sure if this answer is right
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0answers
15 views

Phytoplankton for Indoor Air Quality

Will keeping a phytoplankton culture at home improve air quality? Are there any studies investigating this?
-1
votes
1answer
69 views

Is this answer about the limiting factor correct?

The graph shows the result of adding both phosphorus and nitrogen to different algae populations. I have a hard time figuring out why the correct answer is C, I thought that groups 4 and 5 would have ...
1
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1answer
38 views

Advanced Higher Biology 2017 - EPT Index

I was recently completing a biology past paper the Scottish SQA 2017 Advanced Higher Biology Qualifications. The question is as follows: To solve this, I did: EPT Index = 100*(striped stonefly + net ...
2
votes
0answers
27 views

eosinophil question

Which of the following statement(s) is/are incorrect? A. All cells of the immune system originate in the Bone Marrow B. Lymphoid progenitor cells originate from a pluripotent stem cell C. B cells ...
0
votes
1answer
28 views

Sex determination in Drosphila [closed]

Ive been taught that its based on genic balancing. But I recently saw this question that has caused me some doubt. I thought it would be the 1st option but unfortunately they said it to be the 3rd. ...
-3
votes
1answer
44 views

What is the type of conservation in which seed banks are an example? [closed]

Firstly I think this question is quite ambiguous (I did not come up with it) so sorry. I have only come across 4 'types' of conservation: environmental, animal, marine, and human conservation. I am ...
0
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0answers
5 views

What is the main difference in primary production for non-phytplanktonic production?

I'm trying to see if someone can help me with giving a short answer on the question above. The question I cannot seem to answer myself is related to coastal and zone management. The question relates ...
2
votes
1answer
77 views

How would one go about isolating a specific mRNA out of a pool of others? [closed]

I'm writing an essay about DNA recombinant techniques where the question asks to outline all the steps to arrive at having a colony of bacteria expressing a gene of interest.The question makes you ...
0
votes
2answers
28 views

Number of different clones of B lymphocytes

My professor told us that there are about a million different B cells based on their surface receptor. I have read that we have about 30000 genes in all. Since receptors are proteins how do these ...
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votes
1answer
23 views

Prove that the worms are unicellular

In Biology class our teacher divided the class in two groups. Our group(i'm in) has to prove that the worms are unicellular(although it is not true). The other group has to prove that we are wrong. ...
2
votes
0answers
25 views

Sucrose inhibit onion root mitosis? Why?

I am doing an experiment about onion root growing. I had put an onion in different solutions of $C_{11} H_{22} O_1$ in H2O —with the root touching the water—: 0,1M; 0,2M; 0,3M; 0,4M; 0,5M. The ...
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votes
1answer
38 views

Understanding Genetic Dynamics of Specific Problem

The following questions comes from International Biology Olympiad 2014, theoretical part B. It states: Earlier research suggested that the red flower pigment of plant species was the result of a ...
0
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1answer
65 views

law of independent assortment [closed]

Self fetilization of F1 dihybrids, following independent assortment of alleles result in: ...
0
votes
0answers
20 views

Prepotential in cardiac cells

I came across this MCQ in my physiology book, it says: Prepotential ........... a. is present in ordinary ventricular muscle fiber b. slope is decreased by sympathetic stimulation c....
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0answers
28 views

What causes this shade in gel electrophoresis

Currently in uni I have recently done a exercise of extracting DNA from yeast cell. This is somewhat related to homework, but instead of asking about the answer im wanting to understand why there is a ...
4
votes
1answer
146 views

Which statement is incorrect for Rubisco?

My question is this: Which of the following is NOT correct for rubisco? a. It is the most abundant enzyme b. It catalyzes two different reactions c. It is involved in photorespiration d. It is not ...
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2answers
260 views

Genes & Map Units

Two genes of a flower, one controlling blue (B) versus white (b) petals and the other controlling round (R) versus oval (r) stamens, are linked and are 10 map units apart. You cross a homozygous blue ...
12
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2answers
1k views

Why aren't 'exons' named 'introns'?

Why are introns called 'introns' when they are the actual ones who are getting spliced out from the pre-mRNA. Shouldn't exons be named introns as they are the ones that are 'in' and are not 'exiting'? ...
0
votes
1answer
34 views

How do you find probabilites of carrying an X linked recessive disease in a blank pedigree given only one phenotype?

In the above pedigree, the black square indicates the male affected with Hemophilia which is a X-linked recessive trait. What is the probability that the proposed child, which is a male (indicated as ?...
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0answers
58 views

How do I explain enzyme specificity and reaction (lactose into glucose)?

My group did a lab where we tested milks dairy, rice, almond, and soy for glucose before and after inserting a lactase solution. Dairy tested negative before and positive after. Rice tested positive ...
7
votes
2answers
104 views

Is the xylem like a tissue paper?

I am a 5th grader learning about the plant transport mechanics and I learnt that the xylem is made up of dead cells.So if water travels up the xylem and water travels only 1 way, is it like how water ...
1
vote
2answers
219 views

Intermediate of Krebs cycle that can form Chlorophyll?

This was a question in a test in my school today. Q) Which intermediate of Krebs cycle further can form chlorophyll? A) Oxaloacetic acid B) Citric acid C) Succinyl CoA D) Fumarate Given answer was ...
7
votes
1answer
140 views

Why does the olive tree produce a bitter tasting fruit?

What is the survival value for the olive tree to produce a bitter tasting fruit, even when it is ripened? I realize some fruits and berries are species specific, i.e., meant for specific animals to ...
1
vote
1answer
88 views

Mathematical model about the relationship between two animal species

I'd like to relate a mathematical model with two animal species. This is the model: $$ \begin{split} \frac{dN}{dt} & =rN-\frac{rN(N+M)}{k} \\ \frac{dM}{dt} & =r'M-\frac{r'M(N+M)}{k'} \end{...
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0answers
32 views

Homework: Diffrentiate between 2 toads

How to differentiate between 2 toads one of them result of artificial parthenogenesis and the other from renucleation? I answered that the toad resulting from artificial parthenogensis is identical ...
0
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1answer
42 views

Homework - Genetics linkage problem

A farmer purchases f1 hybrid seeds. These seeds contain four heterozygous loci that give a significant increase in crop yield when compared to either homozygote. Two of these loci are on the same ...
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0answers
22 views

Producing 1,2 propanediol in engineered organism

So we have the following pathways in a engineered organism to produce 1,2 propanediol: So I don't understand why wouldn't we knock out the acetic acid since it is a sideproduct. Only reason I could ...
0
votes
0answers
48 views

Translation in prokaryotic cells

For translation to occur in the mRNAs of prokaryotic cells, the presence of ribosome binding sites (RBS) for each Open Reading Frame (ORFs) is required. How does translation occur in prokaryotic cells ...
0
votes
1answer
1k views

Unsure about definition of “n” and “C” values in mitosis

I am preparing for a Biology exam and I'm reviewing the "n" and "C" notation used in mitosis. My professor said that when the cell replicates its DNA in S phase of mitosis, we get twice the "amount" (...
0
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0answers
39 views

Viral genetic potential

A question goes: The DNA of the adenovirus carries genes. Suggest what these genes code for. It's clear that they code for several specific protein components in the virus like the capsomeres, ...
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vote
4answers
122 views

Best fundamental books? [duplicate]

I’m looking for internationally applauded textbooks on fundamental biology. Books that are a must for a pre-medicine student/high school advanced. Currently, I study Biology by Neil Campbell, Jane ...
1
vote
1answer
74 views

Which function do nicotinic receptors have in the periphery?

I came across this question today, it says: Nicotinic receptors stimulation is directly responsible for ….... I should fill the spaces by one of the following choices: Increasing the excitability ...
-1
votes
1answer
52 views

R nought calculation ( SIR model)

1 person gets bitten by 9vectors /night, the vector transmits the pathogen to 0.035 new hosts. Duration of infection: 9.5 months.What is R0? I am struggling with this question for ages as I would ...
3
votes
1answer
221 views

Question about different gametes that can be produced

I have a question from a past exam that asks the following: "For the organism of genotype AABbCcDDEe (homozygous for 2 genes, heterozygous for 3 genes), how many different types of gametes will be ...
1
vote
1answer
75 views

Serial dilutions

A student wants to make serial dilution of a sample. She starts with a 1mg/ml sample and 10 tubes, (labelled 1-10) each containing 2 ml buffer. The student puts 1ml of sample solution into tube 1 ...