Questions tagged [homework]
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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Is Protein-to-DNA ratio a good estimate of cell size?
I need help interpreting the result of an experiment. My class performed an experiment measuring protein concentration between heart, liver, and kidney tissue samples. The results were:
Heart: 4.714 ...
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True or False: Endocytosis delivers vesicles directly to the cis face of the Golgi complex
Does anyone know the answer to this question, and also the explanation of to why this is True or False?
I know that Endocytosis is the process of uptake of materials into cells including ...
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Why is a urea solution hypotonic relative to RBC?
If I place a RBC in 0.5M urea we see haemolysis.
My textbook says that "the solution is hypotonic. Urea enters the RBC down it's concentration gradient. Water follows the movement of urea by osmosis. ...
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Evolution question on speciation? Really confusing!
Okay, my teacher assigned this homework question, but nothing like this was ever given in our textbook.
Suppose that a type of tree tends to speciate over 10 million years and a species of fly tends ...
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How do I determine this logistic growth model formula?
The Question
Two yeast cells were placed into a special container to which food was
continually added, to keep it at a constant concentration. All other
factors were set for optimal yeast ...
user49181
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In plant photosynthesis, in the light dependent reactions, why is 3 ATP produced per 2 H2O?
I've been looking at the light-dependent reactions on Wikipedia and Khan Academy.
This is the net reaction:
$$2H_2O + 2NADP^+ + 3ADP + 3P_i \to O_2 + 2NADPH + 3ATP$$
So for every $2H_2O$ I expect $...
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What is the difference between optokinetic and vestibular nystagmus?
Optokinetic nystagmus is for stabilising the pictures we see when we are observing moving objects for example if we are rotating on an office chair. If we wear a mask while rotating however, the ...
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Blood pressure in various blood vessels and heart
What are the typical systolic and diastolic blood pressure in arteries,capillaries, veins and the heart?
I know it must be highest in the arteries. arteries>capillaries>veins
Arteries: 120-80mmHg (...
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About. Autosomal recessive diseases in genetics
What happens if homozygous dominant alleles are present in an individual for an autosomal recessive disease will he be affected ?
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What happens between two nodes in an evolutionary tree?
Hey guys can you help me with this one!?
What happens between two nodes (in an evolutionary tree) or a between a node and a tip?
A) at least one character changes
B) all organisms die
C) ...
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Calculating PCR Cycles
I have a problem understanding a PCR exercise, it says to calculate the number of cycles to get 1µg of the DNA fragment, starting from 10ng and then from 500ng, I know about 2^n, and the exercise even ...
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Protein electrophoresis
Three proteins A, B and C of equal molecular weight are being investigated in a study. They contain six, four and four cysteine residues respectively. Only Proteins A and B were treated with β-...
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Why does photosynthesis occur even in blue light when the photocentres are activated in red light
From Engelmann's experiment
Engelmann used this device to illuminate a strand of Cladophora (not Spirogyra) with light from the visible spectrum, exposing different sections to different ...
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Monohybrid Recombinant Frequency? (three point Gene Linkage)
I am curious to know if it is completely impossible calculate recombinant frequency for monohybrids ( three point link, gene map etc.)
Here is an example:
Marker 1
xx= 25
xy=100
yy= 20
Marker 2
...
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When in the cell cycle is the number of chromosomes normally reduced?
Page 96 of the Study Guide for Campbell Biology, 11th Edition has the following question:
A reduction in the number of chromosomes per cell occurs
a. During meiosis I
b. During meiosis ...
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How are chromosomes counted at the end of mitosis in a plant cell?
Page 89 of the Study Guide for Campbell Biology, 11th Edition has the following question:
A plant cell has 12 chromosomes at the end of mitosis. How many chromosomes would it have in the G2 ...
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Is pith a ground tissue with no specialized function?
Here is a question from the book My Max Score SAT Biology E/M Subject Test (where the SAT is the exam taken by American high school students):
Ground tissue with no specialized function
A. Xylem
...
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How many birds in this population would be expected to have either red or white feathers?
Question: The red and white feather pattern of a bird is determined by a gene that has two alleles, band R and W,which show codominance. Some birds have completely red feathers (RR),some parrots ...
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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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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 ...
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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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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 ...
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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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Is α-keratin a fully functional protein?
Is α-keratin before it coils with another polypeptide, makes chains, and build intermediate filaments a fully functional protein?
I mean, is the single monomer of α-keratin a protein or does it have ...
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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 ...
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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 ...
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How to find the amino acid in the DNA protein
3' A T A G T A C C G C A T G T A C G G G C G A G A C A T T C G A G C A T T C A T 5'
This a Template DNA.
How to find the number of amino acids amino acids ...
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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 ...
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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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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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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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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 ...
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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 ...
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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 ...
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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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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 ...
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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 ...
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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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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. ...
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Sucrose inhibits onion root mitosis? Why?
I am doing an experiment about the growth of onion roots.
I put onion plants in different solutions of sucrose in water — 0.1M, 0.2M, 0.3M, 0.4M, 0.5M — with the root touching the water.
Measurements ...
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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
...
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law of independent assortment [closed]
Self fetilization of F1 dihybrids, following independent assortment of alleles result in:
...
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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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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 ...
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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'? ...
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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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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 ...
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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 ...
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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 ...
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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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