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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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0answers
8 views

Can you explain how interspecific competition can affect the population of a species? [on hold]

Can you explain how interspecific competition can affect the population of a species?
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1answer
40 views

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

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
1answer
33 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
69 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 ...
1
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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
0
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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
38 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
0
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0answers
9 views

Phytoplankton for Indoor Air Quality

Will keeping a phytoplankton culture at home improve air quality? Are there any studies investigating this?
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votes
1answer
61 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
35 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
23 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
23 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. ...
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votes
1answer
42 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
64 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
26 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
22 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 ...
0
votes
1answer
37 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
votes
1answer
61 views

law of independent assortment [closed]

Self fetilization of F1 dihybrids, following independent assortment of alleles result in: ...
0
votes
0answers
11 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....
0
votes
0answers
27 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
78 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 ...
1
vote
2answers
196 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
votes
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
31 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 ?...
0
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0answers
43 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
101 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
184 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
127 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
85 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{...
1
vote
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
votes
1answer
41 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 ...
1
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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
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0answers
43 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
475 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
votes
0answers
36 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, ...
1
vote
4answers
115 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
52 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 ...
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votes
1answer
49 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 ...
2
votes
1answer
92 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
74 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 ...
1
vote
1answer
254 views

Questions about apoptosis [closed]

Is apoptosis a part of cell division? Can apoptosis occur if DNA is damaged beyond repair?
-1
votes
2answers
61 views

What is the likelihood of a single human gene to the same gene from the other human?

The human genome comprises 3,234.83 Megabases and contains ~ 19,000 genes. It has been estimated that the genomes of humans are 99.9% identical. How likely is it that any single gene might vary from ...
0
votes
1answer
145 views

Genotype result of double fertilization

So, clearly, the endosperm would be a fusion of the polar nuclei and one male gamete. Does this mean that each male gamete would have a T allele on it? I can't seem to figure out a way to predict ...
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votes
1answer
46 views

S.pyogenes binary fission rate/speed

For my Math IA (IB SL) I want to calculate the average amount of time that one viable S.pyogenes bacteria will need to create an ID50. I cannot find the average speed for the divison of any ...
0
votes
0answers
51 views

Photorespiration prevents plant from photo oxidative damage?

Can photorespiration protect plant from photo oxidative damage be dissipating excess of excitation energy? This was a question in a test and the answer was yes. But according to me, photorespiration ...
-1
votes
1answer
168 views

Onion Cells or Pear Cells?

I am researching different cells under a brightfield microscope for homework and am having trouble determining whether or not these cells are Onion cells (Allium cepa) or pear cells (Pyrus) under a ...
1
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0answers
18 views

response elements in transcription regulation

I'm studying eukaryotic gene regulation and I want to know whether there are some instances where transcription factors don't need to bind to response elements to initiate transcription. RNA ...
1
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0answers
35 views

Why is the chemical of an hexose not sufficient to ID the molecule? [closed]

Here is the homework question I have to answer to The Chemical formula C6H12O6 can mean any number of different hexose sugars that share the same chemical formula. To tell the hexoses apart, you ...