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6
votes
2answers
235 views

HIV and effectiveness of inhibitor cocktail over single inhibitor

I'm looking for clarification on the answer to this question. It's in my biochemistry class but I figured this is more Biology than Chemistry, so I'm asking it here. The question is: One of the ...
0
votes
0answers
6 views

Does using fertiliser reduce the energy required for active transport in plants, for the ion in question

Apologies if this belongs in the chemistry stack exchange. I was just wondering if it did, as carrier proteins require energy to get a particular ion into the plant.But does it take more energy in ...
1
vote
1answer
28 views

Understanding intra and extracelullar concentrations (membrane potential)

I have 4 question (not homework) What happens to the cells membrane potential if: a) Na+ outside rises by 40mM b) K+ inside rises by 10mM c) K+ outside rises by 10mM d) A- (impermeable ion) ...
0
votes
0answers
21 views

Laboratory question about meosis dye [closed]

We are doing the meosis lab in intro bio course. Here are two post lab questions that I couldn't figure them out! In mitosis lab, under the microscope, the toluidine blue appeared as dots inside the ...
3
votes
1answer
38 views

How does electrolarynx work?

I have heard that this is an effective replacement for patients who have a dysfunctional larynx, partly due to cancer. I am curious to know the inner working of this device and why such a robotic ...
2
votes
0answers
58 views

How many proteins are synthesized in human body throughout life?

My idea to calculate this is: Define up to what age will do the calculation. (for instance 60) Determine how many cells born and died up to that point in life. (by type of cell) Determine how many ...
2
votes
2answers
99 views

are the spontaneous generation and evolution the same idea but in a different time scale?

I was in my biology class, learning the history of spontaneous generation and how this idea was discarded. I told my teacher that is the same as evolution but in a different timeline. I Argue that ...
1
vote
0answers
60 views

Cluster Analysis question [closed]

How many clusters are in a cluster analysis containing patient zero, primary contacts, secondary contacts, tertiary contacts, and quaternary contacts? I'm not sure. We are doing an ELISA lab. Should ...
0
votes
1answer
80 views

Answer the questions in one word with help of clues and images given [closed]

Name the things associated with Antonie Van Leeuwenhoek - (6 pictures are given for help and four of them are associated with these clues) a)Leeuwenhoek was the first to describe these and hence ...
2
votes
1answer
96 views

Which process is needed to complete male reproductive development?

In order to properly complete male reproductive development: ...
0
votes
1answer
58 views

What is the importance of hydrogen bonds in water? and other questions: [closed]

These are extremely simple questions — basic biology — but I would like to make sure that the way I have answered is at the very least correct. Hydrogen bonds are very weak, so how is it possible ...
1
vote
1answer
39 views

How to measure the total number of cells in an average human body?

I have got one assignment to calculate the approximate sum total of all cells in the human body. How to tackle this problem? I know that the current statistics is $10^{13}$ cells. I wanted some hints. ...
1
vote
1answer
64 views

How to estimate the DNA density in human sperm head? [closed]

I have got an estimate of sperm head volume from internet.Like consider it as a disk of order 4-5µm. Now I wanted to find the DNA density in the sperm head. How to find that?
3
votes
0answers
38 views

A Genetic linkage problem [closed]

I have recently switched from electronics to computational biology. So having some hard time with my homeworks. Can someone guide me on this problem? Consider 6 genes A, B, C, D, E, F, G. Some ...
4
votes
1answer
51 views

Microbial Fuel Cell Reaction

I found a formula online which explained the reaction which occurred in the anode chamber of a microbial fuel cell but there was a typo $\small NADH + Ferredoxin_{(ox)} (NADH-Ferredoxin\ ...
4
votes
1answer
114 views

which signalling pathway is involved in cancer?

Columnar epithelial cells from the colonic mucosa are studied to identify abnormalities in cell signaling pathways. Abnormal epithelial cells from colonic adenocarcinoma are shown to have a mutation ...
0
votes
2answers
89 views

alpha tubulin molecular weight problem

Is there any academic reference that shows α-tubulin is around 50-55 kDa? The only thing I found is some data sheets from companies. I need the real reference.
4
votes
1answer
65 views

Epistasis Involving Multiple Loci

The following problem is from Schaum's Outlines on Genetics, 5th edition, by Elrod and Stansfield. I'm having some trouble solving it. It is found under a section entitled "Interactions with Three ...
5
votes
2answers
454 views

Diffusion of Hypotonic solution into solution with glucose and starch

Cell walls are selectively permeable to ions and organic molecules. Sometimes the selectivity is passive and a reflection of the physical laws governing diffusion. We can do simple experiments that ...
1
vote
1answer
41 views

Conclusions from hybridization results

A double stranded DNA was denatured in a mixture that included mRNA from a gene in the segment. The mixture was then cooled to promote RNA and DNA hybridization. The following figure the results. ...
2
votes
1answer
33 views

What are the criteria for determining the origin and end of muscle anatomically?

For example the pectoralis muscle starts from sternum region and ends on the acromion or coracoid process. Why you can't say that it starts acromion process and ends on the sternum?
2
votes
1answer
35 views

Drosophila grey / yellow

I am studying biology by myself via distance-learning. I have been trying to solve the following problem for a while now and hoped you could help me. As this is "homework" I would appreciate hints ...
1
vote
1answer
97 views

Transverse diffusion of lipids in red blood cells

The membrane of a human erythrocyte has polarity: Phosphatidylethanolamine and phosphatidylserine are predominantly on the inner side. Phosphatidylcholine and sphingomyelin are predominantly on the ...
2
votes
1answer
18 views

Question regarding 2 constructs of tobacco plant

Six independent transformation experiments of tobacco leaf explants were carried out using two different constructs - (1) construct I containing only a Hygromycin-resistance gene $(HYG^R)$ as a ...
4
votes
3answers
93 views

Membrane potential after exposure to glutamate

Neurons were kept in a physiological solution. During the resting phase, the membrane potential in the axoplasm of neurons was negative compared to the extracellular space and a potential ...
1
vote
0answers
43 views

Infering the statistical tests performed in a paper [closed]

I am in great need of help in order to infer the statistical hypothesis tests performed in this paper (Xanthelasmata, arcus corneae, and ischaemic vascular disease and death in general population: ...
0
votes
0answers
29 views

Hypothalamic breakdown and effect of temperature on membrane lipids

I'm in my last year of high school and doing a research assignment on thermoregulation. In the excellence level exemplar for the standard, a student made the statement: Once the body's internal ...
-4
votes
2answers
71 views

How are atoms created? [closed]

From small baby to the old age, we will be grown. We are composed of bunch of atoms, multitude of atoms. When you are grown from baby to the teen age, everyone will say "he has grown!" What do you ...
3
votes
1answer
62 views

Amino acid profile of GPCRs

You are studying cellular signalling through a newly identified GPCR. Specifically you’re working on a pair of newly identified GPCRs, GPCR-A and GPCR-B. Each binds the same small ligand, but ...
2
votes
1answer
57 views

tetrads in meiosis are held together by what

This is from SAT subject biology test practice question. The answer it gave me was both chiasmata and centromeres. I can understand they are held by chiasmata but why also centromeres? I looked it up, ...
0
votes
1answer
16 views

What is Saccus in Embryology?

The word seems to be of German origin. I have it here Saccus lymphaticus inguinalis, Saccus lymphaticus jugularis, Saccus lymphaticus posterior, Saccus lymphaticus retroperitonaealis. I ...
-2
votes
2answers
88 views

Punnett square and hybrid cross [closed]

A plant breeder crossed two plants, one with red flowers, and the other with white flowers. Red is dominant. Calculate the phenotype and genotype ratios of the F2 generation of this cross. Is this a ...
3
votes
1answer
53 views

relative-rate of evolution

I am supposed to calculate the relative rate of evolution of two sequences (human and sheep) with a chicken serving as the outgroup. The sequences are pretty long, so I will just create a short ...
0
votes
1answer
49 views

Possible Genotypes — Linked Genes

Please consider the following question: Genes A and B are located on the same chromosome. If two individuals with the genotype shown below are crossed, which genotype could be formed? Let / ...
-1
votes
1answer
47 views

What is this abbreviation CT in female reproductive system [closed]

I have this sentence in my notes Ovary is surrounded by tunica albuginea and the cortex keeps the primordial follicles. The medulla containing CT and blood vessels develop from mesonephros. I ...
1
vote
0answers
28 views

Codominance and Partial dominance [closed]

The following genetic tree is given regard the fur color of some animal. The color determined by one gene that have two alleles and 3 genotypes: black, white and inlaid. I've been asked to ...
1
vote
1answer
64 views

Population Genetics Question

Can someone please help with this question? Here is my working (just in case it is not clear: 1/300*1/30*1/2) but is this actually correct or do I need to multiply by 0.5 once again? I appreciate ...
0
votes
0answers
121 views

How do I determine the parental type here?

Please consider the following question: You cross Drosophilia and receive the following offspring: 965 wild-type, 944 black- vestigial, 206 gray- vestigial, and 185 black- normal. Explain your ...
0
votes
1answer
32 views

Quantitative Traits Genetics

Can someone please help with this question? I'm not so sure whether part A should be 11 inches or something else. Also, is part B correct
-1
votes
1answer
55 views

Bilayer synthesis? [closed]

If we want to design a bilayer from Myristic acid (14 carbon fatty acid). The average bond length between C-C is 1.5 A. What will be average thickness of the membrane? Edited to include the OP ...
0
votes
0answers
16 views

What are conditions for a membrane to be settled ? (centrifugation)

The cell membranes have 60% of proteins and 40% of lipids. And we know that medium density of proteins is 1,2 g/cm3 and the medium density of lipids is 0.92 g/cm3. How can we calculate the medium ...
0
votes
1answer
44 views

Dimensional analysis Question

So I'm new to the dimensional analysis world and I'm little confused and the answers I'm getting are not convincing :( if the concentration of hemoglobin in a 5ml sample of blood is 34 g/dL. and red ...
1
vote
2answers
195 views

How much of your stock solution should you take to make the 1000 cells/mL mixture? [closed]

You need a solution containing 1000 buccal cells/mL. You count that you have 125 buccal cells in 50uL, from a total solution of 8 mL. How much of your stock solution should you take to make the 1000 ...
2
votes
1answer
29 views

Neuroscience: zapping an axon connected to thermoreceptor

Let’s say an experimenter has an electrode that can give a shock to a single axon. She takes that electrode and zaps an axon connected to thermoreceptors in the hand of her subject. I) What would the ...
0
votes
0answers
25 views

spinal cord lesion and result in somatic sensation

Jimbo suffers a lesion to the entire right half of the spinal cord at the T6 level. A few weeks after his injury, his doctor tests his right and left legs for somatic sensation and tone. fill out her ...
1
vote
1answer
104 views

Is Natural Selection like a Copy Editor?

I am stuck on a Homework Question. It says: Evaluate the following statement: “Natural selection works like a copy editor; it works only with what is already present in a population.” (Note: ...
1
vote
1answer
44 views

What is ischaemia exactly?

I think it is decreased blood supply to organs and tissues. I also think it is the stopped circulation. However, both ones cannot be right, I think. What is ischaemia exactly?
2
votes
1answer
32 views

What can thrombosis lead to?

I am thinking this question. Thrombosis can result in organisation of thrombus, sepsis thromboembolism, fibrinoid swelling adiposity. I fibrinoid swelling (edema) (4) can occur. Also, I think (3) ...
2
votes
1answer
52 views

Lytic Viruses — Cell lysis?

So in the video my instructor sent on viruses, he said that for lytic viruses, new viruses manufactured by the host cell could get out of the cell in one of two ways. The new viruses would leave by ...
0
votes
0answers
16 views

Southern/Western blot analysis and pedigree diagram? Help needed. [duplicate]

Hello everyone. I urgently need help with this question please. I have filled in the blanks using the results in the figure provided in the sheet. However, for number (b) is a little hard to ...