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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What is a simple small scale procedure for plastination of a cucumber?
Question
In words a high school student will understand, what procedure can a student apply to plastinate a cucumber?
A cursory article on plastination can be found here.
Motivation
When someone ...
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Hardy Weinberg Equilibrium; Homozygous individuals
I have the following exercise that I can't solve:
In a sample there are 16 homozygous A1 allele carriers
(A1/A1) and 24 heterozygous A1/A2 allele carriers. How many homozygous A2 allele carriers (A2/...
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Can phenotype change without change in genotype?
If a person with lighter skin is to live in areas close to the equator for a long amount of time, their skin would get darker, and hence their phenotype gets 'altered'.
If I'm to look at their gene ...
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Flow of left ventricle into the aorta
I am currently practising for an exam and am having trouble understanding one of the exam questions:
The table gives the blood flow rate in various parts of the fetal circulation.
Flow rate in mL min-...
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Probability of an $AABbCC$ offspring given the cross $AaBbCc\times AaBbCc$, is my solution correct?
So I have been working through the drills in the 26th edition of AP Biology Prep by The Princeton Review for fun when I came across this question in the Chapter 12 drill that I'm not really sure about ...
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Evolution of Anoles
For context, I am currently looking at this virtual lab of Lizard Evolution by HHMI biointeractive.
Trunk anoles from an island called Iron Cay were placed in a few experimental islands filled with ...
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Calculation of blood flow rate and pressure change in heart
Question: Blood flows from the left ventricle of the heart through the aortic valve and then to the aorta for system circulation. In a patient, the diameter of left ventricle outflow tract (LVOT) is ...
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Competitive inhibition - Similarity between substrate and inhibitor
I have this question -
Q. Competitive inhibitor which binds to the enzyme (a) has structural similarity with the product (b) is chemically similar to the substrate (c) has physical structure similar ...
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Is kranz anatomy not a defining feature of $C_4$ plant?
In NCERT Class 11 chapter 13 it is written that
The particularly large cells around the vascular bundles of the C4 plants are called bundle sheath cells, and the leaves which have such anatomy are ...
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Looking for literature that gives a systematic presentation of geometric and topological features of trees
Introduction
I am a software engineer specializing in procedural generation of 3D models, and currently I'm building a generator for 3D models of trees, founded on the theoretical work of Aristid ...
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What really is an allele?
My textbook says:
genes which code for a pair of contrasting traits are known as alleles.
Then that means T and t are alleles. Further, it says:
Mendel also proposed that in a true breeding, tall ...
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Identification of cells containing the gene of interest at a double strand break instead of undergoing recombination
If I tried to knock in a gene for example KANMX and want to swap it with say some gene "x", but, since, there can be double strand break in the DNA and KANMX may get inserted within the ds ...
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Genetics question on recombination frequency
A space probe discovers a planet inhabited by creatures that reproduce with
the same hereditary patterns seen in humans. The phenotypic characters are
height (T=tall, t=dwarf), head antennae (A-...
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Why would it be impossible for gram-positive bacteria to store sulfur as gram-negative sulfur-oxidizing chemolithotrophs can?
I have a question that I am not sure what is the correct answer on <<Brock's Biology of Microorganisms>>
When the book introduces "Cell Inclusions", there was a mini-quiz that ...
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Inferring mother's allele probability based on father and children
I am currently in the process of analyzing our family's genome. I do have access to his, mine and our father's genome, but not to our mother's (deceased). I was wondering how I could combine our 3 ...
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Nitrate fertilizer problem
Take the above problem. I understand how to do the calculation. However I can't seem to understand the units of the answer in the calculation.
The answers illustrate the units as t/ha^-2 which is ...
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Herbicide resistant crop plants
Consider the above multiple choice question. I can't seem to understand why the answer is B. How does genetically modifying the crop plant have any effect on the weeds?
The way I understand genetic ...
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Why were there relatively fewer papers about cell fusion before the 1950s?
While working on my cell fusion technology report, I saw PubMed's cell fusion graph of results by year. There have been studies or research since the early 1900s, but until the 1950s, there were no ...
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Hardy-Weinberg Equilibrium help
I am currently working on understanding Hardy-Weinberg Equilibrium problems. I have come upon two examples of a problem in two different Youtube videos which got me confused:
Example 1:
19% of a ...
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Albino pedigree question
https://www.proprofs.com/quiz-school/playquiz/?title=pedigrees-quiz is a link to the website containing this question.
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What causes Erythroblastosis fetalis?
So this is what I understood about the disease by researching about it
When a Rh-ve mother has a Rh+ve baby in her womb,
The placenta prevents mixing of fetal and maternal blood preventing antigen ...
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What is the difference between a macrophage and dendritic cell?
I am aware that both these cells (monocytes) are phagocytes and are able to present antigens upon their own Class II - MHC integral proteins.
Other than their difference in structure (size and shape), ...
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Paternity testing using gel electrophoresis
When using gel electrophoresis to determine the father of a child, each band of the child must match with either the mother or the father. So half must come from the mother and the other half from the ...
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A level 2022 Biology percentage increase question [closed]
In January 2022 WBI12/01 they asked:
9c. In 1963, there were only three males and 12 females of
C. hoodensis left in the wild. These 15 tortoises were used in a
breeding programme.
ii.The wild ...
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Price Equation in Evolution
I am trying to solve for $\text{cov}(w_i,z_i)+E(w_i\Delta z_i)$ as it apears in Price Equations in terms of the mean $\overline{w}$ and variance $\sigma_{w}^2$ of the fitness of a population where I ...
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Gametes produced after single and double cross overs
A female genotype, shown as abc / +++ produces 100 meiotic
tetrads. Among these, 68 showed no cross over (NCO) events; 20 showed
single crossover (SCO1) between a and b; 10 showed single crossover
...
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Question about using Mendelian inheritance to reverse-guess the parent genotype
I would like some help with a question about Mendelian inheritance, based on the following information (I assume this is autosomal and not sex linked):
-- Start of information --
"As flatfish (...
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Time required for DNA replication in E. coli
In a particular strain of E. coli, it was observed that DNA polymerase could add nucleotides to a growing chain of DNA at the rate of 600 per second. If the genome of this organism is 1.1mm long ...
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Calculation of solute, pressure and water potential
What would be the water potential (Ψw), solute potential (Ψs) and pressure potential (Ψp) at equilibrium when a cell with Ψs= – 0.7 MPa and Ψp= 0.7 MPa is placed in a solution with Ψs= – 0.5 MPa? (...
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Surface Area to Volume Ratio and Ice Baths
Hi I was taking a practice test and stumbled across this question. I couldn't find information about this on the internet. Does anyone know why B is the answer? Thanks
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How can I confirm that this pedigree is of a pseudodominant trait?
This is an example of an autosomal recessive trait masquerading as autosomal dominant. I carried out genetic analysis for each generation as if the trait was either recessive or dominant, and both ...
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Question about manifestation of an X linked disease (homework help)
I am doing some practice exams and came across this question. Perhaps the answer is a lot simpler than my reasoning, but after discussing it with others, I still disagree why the answer is clearly and ...
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Problem involving genetic interactions in yeast
I'm having difficulty with the following problem:
In yeasts, genes MEC1 and SGS1 favor survival in response to HU
(hydroxyurea). In the figure below, Δ indicates homozygosis for the
mutant allele ...
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What are the small white dots in an onion cell seen under an electron microscope?
We had to use an electron microscope in class for an assignment and used onion cells. On the 40x and 100x magnification there are tiny white dots and I was wondering if someone could tell me what they ...
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What is a downstream target?
For example, in a systems biology analysis, what is a "downstream target" and why are these significant in pathway analyses?
I have looked for answers on Google, DuckDuckGo, Wikipedia, etc. ...
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Are restriction sites added on to the ends of a DNA fragment or are they just conveniently there?
For a DNA fragment to be inserted, it must have two restriction sites on either end. My textbook makes it seem that this is naturally occurring but it seems a little too convenient, are they added in ...
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Explain why bones cannot undergo interstitial growth as cartilage does
I got a question from a textbook <<Seeley's Anatomy & Physiology Twelfth Edition>> that does not have an answer at the back of the book (only odd numbered questions do have an answer ...
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How does Propionibacterium acnes survive the antibacterial effects of sebum?
Sebum has antibacterial properties due to sapienic acid and oleic acid according to this article on sebum. According to the same article, desaturation of fatty acids increases acne development. ...
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Does hormone participate in metabolic activites?
strong text
My take on question-
All hormone are not water soluble, some are fat soluble also so this option is definiely wrong.
Thyroxine Hormone is do stored in the body in Follicle of thyroid ...
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How many cells are there in C. elegans in each hour of its life?
I'm a high school student planning to write a math essay to model changes in the number of cells in a living organism over time. C. elegans is the only organism that I know with a known number and ...
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How does increased resistance to flow decrease blood pressure?
I have recently encountered this question:
Waldenström's macroglobulinemia is a condition which causes increased blood viscosity due to high protein content in the blood. How would Waldenström's ...
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How much oxygen is released by Hemoglobin per 100ml blood
Question
Red blood cells carry oxygen from lungs to the whole body. The percent saturation of hemoglobin
with oxygen depends on the partial pressure of oxygen. Higher partial pressure of oxygen means ...
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Number of homozygous recessive offspring
A question from the KVPY-SX examination, organised by the Indian Institute of Science (IISc) in Bengaluru, India, held on 3rd November, 2019.
A plant heterozygous for height and flower colour (TtRr) ...
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Understanding Contig NG50
My goal is to do a de novo assembly of a jellyfish. At the moment I'm busy checking papers that did de novo assemblies but I also got some jellyfish papers
Then I stumbled accross this:
Contig NG50 ...
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How can we know which alleles are together on a chromosome?
This illustration says that if the two homozygotes pr+ pr+ vg+ vg+ and pr pr vg vg are crossed to produce a heterozygous offspring (pr+ pr vg+ vg), then:
this cross gives us exactly what we need to ...
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What is the map unit between the genes?
While doing some biology I came across this question:
The following tables present results of plant crosses involving two linked genes: S is a seed-color gene, and L is a plant-height gene. Each gene ...
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renal portal system
I am a high school student.
In my textbook it is written that Mammals don't have renal portal system because they have four chambered heart. I understand that the four chambered heart keeps the ...
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Check simple human fetus answers
Based on this image and questions, could someone please check my answers?
Question 1: At which one of the following points will the blood passing the point be more oxygenated after birth than before ...
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What is the thickness of the membrane if only alpha helixes are embedded of a transmembrane protien?
Given is the representation of a transmembrane protein. Calculate the thickness of the membrane if only alpha helixes are embedded in it. One turn = 5.4Å
Please read:
The reason I didn't submit my ...
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