This tag indicates that the question targets some basic concept or information that might seem trivial to professionals and can be seen as a home assignment in biology-related university courses. Please see the homework policy on meta before asking homework questions.
4
votes
3answers
4k views
Does Human Female Meiosis II occur after fertilization with sperm?
I am reading the answer and I am getting confused by the sentence:
At the end of meiosis I females have two daughter cells and meiosis II
only occurs if and when fertilization occurs by a sperm ...
0
votes
3answers
39 views
Diffusion across cell membranes
I got this question and don't really understand the difference between the answers.
Diffusion is (in cell membrane):
a) passive by nature, no metabolic energy is needed
b) driven process by ...
0
votes
2answers
81 views
Recent and good quality articles on systems biology [closed]
I'm a biotechnology student and I have to write a sort of non-experimental thesis (30 pages long) within the end of a three years study.
I'm very interested in the "systems biology" field and I'm ...
2
votes
1answer
55 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
51 views
Hardy-Weinberg Equilibrium: To compute probability of finding two siblings (random mating)
I've been working a little with M. G. Bulmer's Principles of Statistics (Dover, 1979) and cannot see how to properly compute half of one question. This should be a basic probability computation, but I ...
1
vote
1answer
55 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 ...
0
votes
1answer
69 views
How to classify equilibrium points [closed]
I have the two differential equations:
$$\frac{dN_1}{dt} = N_1(2 - N_1 - 2N_2)$$
$$\frac{dN_2}{dt} = N_2(3 - N_2 - 3N_1).$$
I worked out the equilibrium points to be at $N_1 = 0, \frac{4}{5}$ and ...
0
votes
2answers
49 views
Deterministic model of lambda-phage lysis/lysogeny [MATLAB]
Project 1 Base:
Can someone please help me understand what I need from Project 1 Base code to do questions 1 and 2 from the first image? I'm new to MATLAB so a thorough explanation would be ...
4
votes
2answers
89 views
Difference between biological control and introducing species for conservation?
I have a biology assignment and we have to explain various methods and strategies for conservation, two of which are:
Biological control
Introduced Species
What is the difference between ...
0
votes
0answers
50 views
Analysis of cDNA samples from brain with suspected measles inclusion body encephalitis
I have been given the following question as an assignment but I am not sure what exactly the results mean:
You have been given brain biopsies from 5 patients with suspected measles inclusion body ...
2
votes
1answer
60 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 ...
1
vote
2answers
65 views
Will climate change affect flower population?
There is a flower population elevated 1000 meters above sea level. If climate change causes a 12 degree C increase in temperature over the next 10 years, what will happen to the flowers?
0
votes
1answer
67 views
Number of reading frames in nucleotide sequence
In class of molecular biology was posed this question:
"How many reading frames start in sequence of nucleotides 5' ... ATATGAATGATGACAT... 3' ?"
1
vote
0answers
42 views
Polymerase Observations
DNA polymerase I (PolI) contains polymerase, 3'-5' exonuclease, and 5'-3' exonuclease activities in a single polypeptide chain of molecular weight 109 kDa. If E. coli Pol I is exposed to the protease ...
6
votes
1answer
94 views
How does Topoisomerase II inhibition affect cancer cells?
Topoisomerase II poisons represent some of the most important and
widely prescribed anticancer drugs currently in clinical use. These
drugs encompass a diverse group of natural and synthetic ...
2
votes
2answers
890 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
2answers
77 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 ...
4
votes
1answer
42 views
Parsimony (cladistics)
I don't understand how to sum the changes in a phylogenetic tree.
Here for example: http://www.med.nyu.edu/rcr/rcr/course/phylo-cladistic.html
How do you end up with 8 for the first and 9 for the ...
3
votes
1answer
4k views
What factors affect the rate of transpiration in plant leaves?
I'm trying to get my head around factors which affect transpiration in leaves.
For example, how would applying petroleum jelly to the surface of plant leaves affect their rate of transpiration?
I ...
0
votes
0answers
42 views
Bradford Protein Assay [closed]
Please would somebody help me to solve the following exercise:
Determine the protein concentrations of the four unknown samples (A,B,C,D) using the raw data obtained from a Bradford assay.
...
15
votes
3answers
138 views
What is the optimal frame size for protein secondary structure prediction methods?
The whole question is
What is the optimal frame size for the second and third generation protein secondary structure prediction methods? Justify your answer.
I remember it has something to do ...
4
votes
2answers
417 views
What are the advantages and disadvantages of using beta-galactosidase compared to luciferase as a reporter gene?
In the University labs, we have used Beta-galactosidase as a reporter gene to quantify the expression initiated by the stress-response promoter in yeast. This was done by exposing one of the two ...
5
votes
1answer
85 views
What is the total number of rounds of cleavage during mammalian embryonic development?
That for frog is 12, but what about mammalian embryos?
I cannot find the exact number anywhere.
1
vote
0answers
25 views
How could a pure culture be represented by more than one ssu rRNA sequence?
Your lab works on an organism isolated from radioactive waste. However, you show that 3 very similar, but not quite identical, ssu-rRNA sequences can be amplified from the culture even though it is ...
2
votes
1answer
30 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 ...
1
vote
1answer
47 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
115 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
37 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).
...
1
vote
1answer
694 views
Which enzyme catalyzes transcription and which translation?
My attempt:
Transcription - RNA polymerase
Translation - aminoacyl tRNA synthetase
I know that the ribosome almost runs translation, but I don't think ribosomes are enzymes, which is why I went ...
1
vote
1answer
50 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.
...
2
votes
1answer
67 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?
1
vote
1answer
99 views
Are Bovine serum albumin, Avidin, Ficoll-70 and Dextran-70 positively charged or negatively charged?
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 ...
3
votes
1answer
455 views
Is secondary follicle or Graafian follicle arrested in the second metaphase of oogenesis?
My note about which I am not sure:
Secondary oocyte is arrested in the metaphase II monthly after puberty until fertilization with sperm.
The following picture also satisfies my sentence: .
So ...
1
vote
1answer
85 views
How to manufacture different sized micelles in nano -scale?
I am trying to answer q5:
"How can you manufacture micelles in A) nanometerer -scale B) and in ten nanometer -scale?"
My Thinking
Observations and some thinking
Oil in ...
2
votes
1answer
145 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 ...
1
vote
0answers
34 views
How many pandemic H1N1 2009 virus sequences were submitted by the Indian NIV as of May 10, 2010? [closed]
The handout I was following is maddening. It says; "Go to the NCBI home page and select 'All Resources (A-Z)' and choose GenBank. Follow the NCBI Flu Resource link to determine how many pandemic H1N1 ...
1
vote
2answers
1k views
Restriction Mapping of Plasmid Assignment
pUWL22 is a circular, double stranded, 10.5 kb plasmid. It contains a
gene encoding an enzyme that confers ampicillin resistance in the host
bacterium. Cloning into the kpn I and Sst I sites ...
3
votes
1answer
136 views
Predicting progeny of recessive mutations using recombination
I was asked this question on a test and got it wrong, but I'd like to know how to do it. The answers are shown in the blanks below:
You are studying two recessive mutations in the fruit fly D.
...
4
votes
0answers
41 views
Determine which gene is in the middle complementation [duplicate]
Possible Duplicate:
Crossing mutant strains on minimal media problem
I'm studying this problem for my genetics final:
My Attempt: The answer for part B is met2 and the answer for part C ...
-5
votes
1answer
134 views
DNA chip contains a complete set of random hexanucleotide (6-mers) probes? (Solve) [closed]
can you tell me how to find solution to this question
A DNA chip contains a complete set of random hexanucleotide (6-mers)
probes. Out of the 4^6 = 4096 probes, how many will form perfect
...
1
vote
0answers
70 views
How to find Dmax (genetics problem) [closed]
My attempt: I'm not sure this is right but this is what i did. I found the allele frequencies to be:
A=0.4
B-0.3
a=0.1
b=0.2
I think to find Dmax I just multiply the two alleles with the larges ...
7
votes
1answer
138 views
Finding DNA from Amino Acid sequence problem
My attempt: First I took the single letter AA codes and made them amino acids. So, the first one is Trp which is 5'-UGG-3'. From this I got the DNA sequence 3'-CCA-5'. However, the correct ...
4
votes
1answer
94 views
Finding exons in DNA problem
My attempt: I looked for the TACs because I thought this would be AUG in mRNA and ultimately Methionine (the start codon). But apparently, that's not how you do this problem. Im confused because ...
6
votes
2answers
437 views
What is the main general difference between Mitosis and Meiosis?
I found such a clause:
The general principle is that mitosis creates somatic cells and
meiosis creates germ cells.
However, I cannot agree. Each gametogonium needs to go through mitosis before ...
2
votes
0answers
73 views
Mouse meta-globin mRNA problem
This is an mRNA strand of mouse meta-globin:
5'-ccccagauacggaauucgaau-3'
A) Which small RNA (below) is most likely to regulate expression of
meta-globin?
...
2
votes
1answer
97 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 ...
4
votes
1answer
852 views
What are differences between formation of embryonic disc in chick and mammal embryo?
Exam question which got lowest average points in my university: 1/5 average.
No markscheme available so my attempt below.
I assume that embryonic disk prefers to germ disk such that Formation prefers ...
6
votes
1answer
124 views
Effect of histidine on the binding affinity of HisP
I was asked the following question by my teacher:
A gene regulatory protein called HisP regulates the enzymes for
histidine biosynthesis in the bacterium E. Coli. HisP is a protein
whoes ...
4
votes
1answer
37 views
How do fibers control muscles?
My professor says
Nervus troclearis IV somatomotor fibers supply musculus obliquus superior.
and similarly for nervus oculomotorius III
Nervus oculomotorius postganglionic fibers supply ...
3
votes
1answer
243 views
What are all possible vectors for unicellular human parasites?
I got the given question. They want the following pieces of information about protozoological human parasites:
disease - parasite - vector.
There are 10 proteogenic diseases at the Wikipedia. I ...
