3
votes
2answers
137 views

How far into a pregnancy is it before visible signs of it is apparent and risk of physical trauma increases

I'm doing research for a series I'm writing. in it the main character is pregnant however goes off to fight a criminal organization who have been killing her friends and i want her appearance to show ...
3
votes
2answers
5k views

How does extracellular potassium ion concentration and calcium ion concentration affect the excitability of a cell?

When extracellular $K^+$ concentration increase by a certain amount, excitability of cells is higher because the resting potential shifts toward a higher equilibrium potential of $K^+$, therefore ...
3
votes
2answers
177 views

How does Humira work when injected into patients with rheumatoid arthritis?

OK, I have rheumatoid arthritis and I've been injecting Humira 2 times a month for the last 8 months. As far as I know rheumatoid arthritis is simply an immune system disorder which makes the immune ...
3
votes
1answer
55 views

Euthyrodism and goitre

I read in Tortora and Derrickson that goitre is associated with euthyrodism. How is that possible?
1
vote
1answer
24 views

Giving diuretics to insipidus patient

I read in Tortora and Derrickson that giving diuretics to diabetes insipidus patients may in fact alleviate the symptoms of the disease. How is this possible?
0
votes
1answer
48 views

Growth Hormone and diabetes

Growth hormone and insulin like growth factors are diabetogenic, so I assume that people with high growth hormone (say due to pituitary tumor) may be at high risk for diabetes. Has any correlation ...
8
votes
3answers
267 views

Does the Petri dish lid orientation on workbench affect aseptic technique?

When examining an incubated plate, it is rather clear that holding the plate in one hand and the lid in another is best for aseptic technique, or simply resting the lid on the plate as shown below. ...
6
votes
2answers
4k views

What determines if a gene is dominant or recessive?

Going back to my high school days we were taught about dominant and recessive genes. We were taught how to calculate the geneotype and pheneotype of potential offspring using a small table (forgotten ...
0
votes
1answer
66 views

Function of carapace

Majority of crustacean larvae have expanded carapace drawn out into processes as an adaptation for : a. Protection from enemies b. Planktonic habit The answer given is b but I think it should be ...
2
votes
1answer
259 views

Population Growth Rate Question?

A population of 600 birds faced a problem of biological magnification resulting in a large number of deaths reducing their population to 350. But 230 births also took place and 21 birds immigrated ...
1
vote
1answer
163 views

Effect of pH on life? Use buffer or HCl? How about lactic acid?

I'm trying to find the effect of pH on living things like E. coli and such. At first I thought of using a buffer solution which maintains its level of pH, but it's possible that the inactive ions of ...
4
votes
1answer
152 views

Function of papain in papaya

I know that papain is a proteolytic enzyme present in papaya. It is often used to tenderise meat. What is the function of papain in papaya? Is papain sweet? Does it function as an antibiotic?
3
votes
0answers
59 views

The Operation of tuning in the S1 layer of ventral model

According to my previous question in ventral Stream pathway and architecture, I want now to get a brief example about how the S1 layer is constructed. In other words, how all the simple units are ...
2
votes
2answers
96 views

Breakdown current for human body

If I am not mistaken, during exposure to electricity sources it is the magnitude of the current and not the voltage that kills the human body. If so, what is the order of magnitude of current that ...
1
vote
1answer
908 views

Is Zymase, A Complex of Enzymes? Which ones?

Some websites state that the enzyme zymase (which I understand to be a complex of several enzymes) is responsible for catalyzing glycolysis in order to produce pyruvate. On the other hand, some ...
6
votes
1answer
188 views

Whole genome amino acid composition tool?

I'm interested in a statistical tool to get bacterial codon usage at genomic level. Ideally, the tool should be flexible to analyse hundreds of bacterial genomes. I've looked in MeSH terms database ...
2
votes
1answer
51 views

Exotic Cell Shapes

As far as I know, plant cell shapes are a difficult thing to pin down. However plant cells have cell walls and so can be very rigid. However the only plant cells I've seen have been either block ...
2
votes
1answer
883 views

Lyonization and X-linked disorders?

Lyonization or X-chromosome inactivation is the conversion of all but one, X-chromosomes in Females into non-coding heterochromatin (i.e. deactivated) leading to the formation of one or more Barr ...
5
votes
1answer
314 views

Empirical evidence for species selection

Do we have any empirical evidence in favor of species (or lineage) selection? Do we know some cases that can only be explained (or seem to be only explained) by lineage selection? What are today the ...
1
vote
2answers
223 views

Question about production of CFTR protein

How do organelles such as ribosomes, ER, Golgi and vesicles produce CFTR protein and mucus?
4
votes
1answer
94 views

Which of Perutz et al's protein structures other than 3₁₀ helix were correct?

In 1950, Bragg, Kendrew and Perutz published "Polypeptide chain configurations in crystalline proteins" (open access) and were famously 'proved wrong' by Pauling, Corey and Branson the following year, ...
6
votes
4answers
133 views

How to measure bacterial content

I´m using water container placed on a radiator to humidify room air. Someone might argue that it is a perfect nest for bacteria. I have to put copper coins into the water to kill the bacteria. I ...
4
votes
1answer
64 views

How much can you learn about species variation from a skeleton?

I just read about the discovery of the 1.8-million-year-old human skull in Georgia, and how it suggests that early humans were all one species instead of distinct ones. Would an archaeologist ...
3
votes
1answer
219 views

Ventral stream pathway and architecture proposed by Poggio's group

Please can you give me a very brief explanation about all functions in the ventral stream architecture summarized in this figure: This figure is from Serre et al.'s A quantitative theory of ...
1
vote
2answers
31 views

What are examples of genes succesfully reproducing in ways that is in conflict with helping the individual creating offspring

Most of the time, our genes have common interests with our "self". We reproduce well if and only if our genes reproduce well. In some cases, like in bees, the haploid bees can survive better if they ...
4
votes
1answer
3k views

Isotropy of sarcomere bands in skeletal muscle cells

As seen under a polarization microscope, the A-Band in skeletal muscle fibres is so named because it is anisotropic in its refractive index which is a characteristic of orderly crystalline structure. ...
3
votes
2answers
121 views

Which hydroxyl from either the phosphate or the glycerol is taken during synthesis of a phospholipid head?

The oxygen anion in the phosphate group is likely to be bonded with a hydrogen cation and thus forming a hydroxyl. When the phosphate group is condensed with glycerol to make a phospholipid, is the ...
2
votes
1answer
87 views

Are there known 3- or 4-nucleotide RNA linkers with no RE sites?

Question is rather self-explanatory. I'm looking for a non-cleavable RNA sequence to act as an RNA linker. I mention 3- or 4-nucleotides only, but making such a sequence with 2 nucleotides is rather ...
2
votes
2answers
326 views

Do brain cells shrink during REM sleep or a lucid dream?

In this BBC news article a study shows that during sleep brain cells shrink to open up the gaps between neurons and allow fluid to wash the brain clean. But do the cells shrink and undergo the whole ...
0
votes
1answer
190 views

What is meant by 73 hour birth [closed]

I was reading an article, when I read a sentence saying, His mother ... nearly died less than three years later during Mathers' 73-hour birth. What does mean by 73-hour birth?
0
votes
1answer
45 views

Reassociation of DNA

What is the order in which this DNA samples would would reassociate ? e.coli DNA plasmid DNA viral DNA satellite DNA DNA-RNA hybrid This is a homework question and I have not been given any ...
3
votes
3answers
374 views

Bioinformatics tool for “pairwise alignment” of complementary sequences?

I'm currently working on some ribozyme binding, and I'm looking for a tool that will essentially analyze the regions of the degree of complementarity in two sequences in order to extrapolate ...
2
votes
0answers
78 views

A number of questions regarding chemotaxis assay using PBMCs

In our lab we would like to study the chemotaxis of PBMCs towards conditioned medium obtained following treatment of cancer cells with different compounds. My questions are regarding the method of ...
2
votes
2answers
139 views

Sources for common laboratory Saccharomyces strains?

I'm used to working with bacteria - some of the more common laboratory strains sometimes come with an order from some vendors. What's the most convenient source to order common straings of ...
1
vote
0answers
25 views

How is saltatory conduction faster than conduction of unmyelinated fibers? [duplicate]

It's always the same explanation that currents are able to "hop" along Ranvier nodes instead of passing continuously along the axon making saltatory conduction more efficient than continuous ...
4
votes
2answers
76 views

Transmission of disease from mother to fetus

Can parasite, microbes be passed from mother to fetus through the placenta ? I know some like HIV can be.
1
vote
1answer
94 views

Detecting UV by humans

From my experience humans can detect UV - not by seeing it but by pain in their eyes. Many people (me too) feel pain when looking at UV lamps. When looking at sun through clouds I still can feel pain ...
2
votes
1answer
103 views

.Net DNA/Codon Parser

Does anyone know of an .NET (C#,VB.NET, maybe F#) DNA parser? If not I will probably make one, it doesn't seem like it would be hard. My general idea was to generate something that would report the ...
3
votes
3answers
75 views

Can genes that activate transcription factors also called be called transcription factors?

If the sole known function of a gene is to activate a transcription factor, would that gene also be considered a transcription factor, or is there a word for such genes that are further upstream on ...
0
votes
1answer
40 views

Cellular components of blood cells

There are different types of blood cells in the human body i.e. red blood cells, neutrophils, basophils, eosinophils, monocytes, T-cells, B-cells. What are the cellular components of these cells? ...
3
votes
1answer
397 views

What is needed for a G-matrix?

I have been doing a lot of reading on quantitative genetics and the G- (and B-) matrix lately. I get the principle behind performing the analysis now but I am still not sure how to do it. I'd like to ...
4
votes
1answer
2k views

Difference between mutation and DNA damage

What is the strict difference between mutation and DNA damage? As far as I understand it, a mutation is an alteration in the genetic sequence, having "tricked" the repairing machinery and thus ...
1
vote
1answer
64 views

What is the strength of human cornea?

What is the difference of pressure a human eyeball cornea (cornea, lens and other elements separating vitreous body from air) can handle? Or asking differently: what the outside pressure should be to ...
2
votes
2answers
79 views

Termination of translation

What dissociates first - the last tRNA, mRNA and release factors or the subunits of ribosomes? I tried searching this from Lehninger but couldn't get a clean answer.
0
votes
1answer
114 views

cellular respiration

What are the effects of addition of these chemicals to actively respiring cells ? Which of them would lead to INHIBITION of aerobic respiration ? Would cytochromes be actually taken up by cells ? ...
5
votes
1answer
51 views

Calling for Free Online Data for Paediatric ECG?

I need free online data about heart murmurs to study these: heart murmur frequency , S2 heart sound frequency and its split, murmur timing, and duration, murmur intensity, S3 sound presence and ...
0
votes
2answers
133 views

Won't natural selection miss the overall minimum of a function?

Suppose we have a population of about 1000 with an environment that does not change a lot (e.g. the atmosphere is more or less the same) and we leave this population to evolve. From what I understand ...
1
vote
1answer
135 views

Why do I have a lot in common with my mother? [closed]

I have not spoken to my mother in 15 years but recently connected with her and her side of the family. I was primarily raised in a different sub-culture after the age of 4. As it turns out I ...
-1
votes
1answer
104 views

What are uses of fossils? [closed]

What are the geological uses of fossils and how could it be utilised? From The Institute for Creation Science: Fossils are typically found in sedimentary rock, almost all of which were originally ...
5
votes
1answer
67 views

Shade-loving Plants

In shade-loving plants, the light compensation point is reached at low irradiance because: A. Leaves have more chlorophyll per reaction center B. These plants have greatly reduced respiration rates ...

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