1
vote
1answer
35 views

Are there any forms of heart failure where cell size decreases?

I think hypertrophy happens in most of the cases. However, I am not sure if hypertrophy always happens. I started to think about wet lungs (pulmonary reason for the left-sided heart failure). Can the ...
2
votes
1answer
36 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) ...
0
votes
1answer
64 views

Fibrinous inflammation, exudate and scarring in monotonous movements and ageing

I have palpated many hard organs during my work and studies. I have seen many young and old people who have hard organs, like very hard shoulder - very common. I have interviewed some of them, some ...
2
votes
1answer
58 views

phylogenetic Independent contrasts with unresolved tree

I have a dataset containing morphological and performance measures of species from various groups, including insects, lizards, frogs, spiders etc, and want to analyse the relationship between these ...
1
vote
0answers
150 views

Effects of Genetic Drift on Linkage Disequilibrium

From what I understood of @Canadianer's answer here... Genetic drift randomly causes negative or positive linkage disequilibria, by changing allele frequencies through random sampling. Natural ...
4
votes
1answer
168 views

Why do mosquitoes not collect blood after platelets activate?

This may be anecdotal... The Indian sub-continent is in the rainy part of summer. It follows the mosquito population goes up. So when I sliced my palm, I expected the mosquitoes to collect there in ...
8
votes
2answers
561 views

Can a neuron make a synapse onto itself?

I was wondering if a neuron can make a synapse to itself? I suspect that it would be extremely unusual for a neuron to do this. Anyway, has anyone seen even a single instance of this? Is the process ...
5
votes
3answers
207 views

Can children restore brain cells?

By "children" I mean young people at the age of 10 or lower. I know that the adult brain cannot restore brain cells, but what about children? I mean, the brain must develop from a few cells to a 90 ...
9
votes
1answer
191 views

Seeing strange things in light

I have noticed that if you look directly at tubelight (I have only white ones in my home) and close your eyes little, you see little random shaped colourless things sometimes with slow speed and ...
3
votes
1answer
345 views

How does chromosome cross-over occur?

I have heard that during meiosis, homologous chromosomes from each parent "cross-over", which enables the off-spring to inherit some alleles from the mother and some alleles from the father. The ...
2
votes
3answers
708 views

Why is it that drinking caffeinated tea does not help one to stay awake?

I have never felt after drinking tea that I can have the power of being able to work late at night. Neither have I felt that it helps me to be awake while working or keeping eyes opened while I am not ...
2
votes
3answers
213 views

Many spermatozoa, but just one ovum

Why do men produce so much spermatozoa, that will get discarded, but women, just ovulum, but it's a good one. Couldn't men produce good spermatozoa as a limited edition? Where is the evolutionary ...
2
votes
2answers
153 views

Are there free electrons in muscles, hair, or skin?

Electric shock occurs upon contact of a (human) body part with any source of electricity that causes a sufficient current through the skin, muscles, or hair. In metals many electrons are said to be ...
1
vote
1answer
32 views

To have TBE vaccine during allergic times with mild asthmatic symptoms?

My assistant says that if you have asthmatic symptoms you cannot have TBE (Tick Born Encephalitis) vaccine, although you are living in the active zone of TBE. Cases mild allergic symptoms allergic ...
2
votes
2answers
50 views

In which direction plants' root grow in weightlessness? [duplicate]

As far as I know, roots of plants grow to the direction of Earth's gravity - this is called gravitropism. But what happens if plants are in space? Are they able to perceive gravity in state of ...
1
vote
1answer
31 views

Could super-caffeinating somebody's bloodstream be dangerous?

I'm currently planning out an RPG based on Misfits. Basically young offenders get super powers. I want one of the villains to have a really lame power that they use to become incredibly dangerous. I ...
2
votes
1answer
332 views

Why do genetic drift generates negative linkage disequilibrium?

The very first sentence of the abstract of this article are: "In finite populations subject to selection, genetic drift generates negative linkage disequilibrium, on average, even if selection ...
3
votes
1answer
289 views

Why basement membrane thickens in diabetes mellitus?

Untreated diabetes mellitus may lead to blindness and kidney failure because the basement membrane of small blood vessels in these organs thickens due to increased production of collagen and laminin. ...
1
vote
1answer
143 views

Heterozygosity and overdominance

Consider $m$ loci with heterozygote advantage (overdominance) such that the fitness of the two homozygotes is $1-\frac{s}{2}$ and the fitness of the heterozygotes is $1+\frac{s}{2}$, where $s>0$. ...
2
votes
0answers
49 views

Why is post-vaccination fever for 4CMenB so frequent?

When considering the introduction of 4CMenB vaccine, the Joint Committee on Vaccination and Immunisation said: The sub-committee noted that the clinical trials data suggest that when 4CMenB ...
3
votes
1answer
137 views

Are people genetically predisposed to being interested in specific fields/ideas? How does specialization occur?

I'm not sure if I formulated my question well, but I'm curious about a couple statements made by Steven Pinker and and James Heckman. In this interview: ...
1
vote
1answer
106 views

What is the current molecular explanation of Mendel's pea cross?

With reference to the simplest Punnet square for Mendel's pea plant experiments it occurred to me that I could not connect the little I know about genetics to the little I know about molecules. The ...
1
vote
1answer
72 views

Could the Warburg effect be used to starve cancer cells in situ?

What is wrong with the following chain of reasoning? Nearly all cancer cells rely on high rates of glucose uptake (upto 200 times more than normal cells). This is known as the the Warburg effect. ...
1
vote
0answers
66 views

Relationship between small and large fast-twitch motor units

When large fast-twitch motor units are temporarily fatigued, non-fatigue small motor units in the same muscle are impaired for small delicate tasks. Why? When impulses from the brain comes down, the ...
6
votes
4answers
218 views

Is there a comprehensive life science techniques/methods database?

There are so many techniques/methodologies in the life sciences that we can use to interrogate interesting questions. The thing is, most of us are completely unaware of the available methods we can ...
1
vote
1answer
205 views

definition of tempo and mode in evolution

I am reading Punctuated Equilibria: The Tempo and Mode of Evolution Reconsidered, which mentions the "tempo" and "mode" of evolution. I'm not familiar with the related literature and when I google the ...
1
vote
1answer
29 views

Effect of the health of the male parent at the time of conceiving

Does it matter at all in determining the traits of a baby what the current health of the father is? For example, let's say I got diabetes at the age of 40 because of the poor lifestyle choices. Will ...
1
vote
1answer
52 views

Are bronchioles and alveoli covered by respiratory epithelium?

Which parts of respiratory apparatus are covered by respiratory epithelium and which are covered by other kinds of epithelium?
3
votes
1answer
61 views

How does tree resin capture arthropods?

In regards to a published paper of a spider about to make a meal out of a parasitic wasp (http://www.tandfonline.com/doi/abs/10.1080/08912963.2011.640399#.U1kSV14gVBU), it reminded me of a issue I've ...
2
votes
2answers
756 views

Name of scientist who discovered lifesaving drug and chose not to patent it?

I recall reading about a 20th century scientist who made a life-saving drug that could have patented it and made millions. He chose not to and saved the lives of millions around the globe. I thought ...
0
votes
1answer
34 views

Why rectus abdominis is not proximal muscle?

I am thinking this picture which shows proximal muscles. Why for instance pectoralis major, subclavius and rectus abdominalis are not included in proximal muscles?
2
votes
1answer
47 views

Number of autoregulation and FFL motifs in a network

Suppose we have a network with N* nodes (N* is the number of internal nodes). Every directed link in this network exists with probability p. What would be the number of: motifs that are ...
6
votes
2answers
3k views

Species Identification - small insect: is this a bed bug?

I found this bug in my apartment in Chicago. We had bed bugs in our house the previous year (but we thought we got rid of them). This bug was very small - maybe 2 millimeters in length. These ...
3
votes
1answer
81 views

identification of this flower

I saw this flower in Pulau Ubin in Singapore. Can anyone identify the species of this flower? Thanks in advance!
1
vote
0answers
21 views

Can paralogous genes be under negative selection?

I have just aligned 9 paralogous genes from human, uploaded them into MEGA and calculated negative selection. Can there be negative selection acting in between paralogous genes? Or how should I ...
2
votes
0answers
34 views

Source of information on the evolution of aging/senescence

Do you know a good review (published peer-reviewed or an online course or whatever) that offers a good overview of all hypothesis explaining the various patterns linked with aging? I'd like this ...
1
vote
1answer
784 views

Advantage of being deuterostome

We know that most of the so called "Advanced" organisms are deuterostomes (i.e., development of gut starts from anus). Is there any evolutionary advantage of that? If not, why and how did it evolve?
0
votes
1answer
265 views

How to increase the rate of absorption and assimilation of food? [closed]

i was reading this and want to know excerpt from the above link...
2
votes
1answer
1k views

How to interpret the breeders equation?

The univariate breeders equation is defined as, $\ R = h^2 s$ where $\ R $ is the response, $\ h^2 $ is the heritability (additive genetic variation), $\ s $ is the selection differential. The ...
3
votes
0answers
81 views

identification of species of this bird [closed]

Hi I saw this bird near my school canteen in Singapore in Spring. Can anyone identify the species of this bird? Thanks in advance!
1
vote
1answer
27 views

fibrinogens and fibrins - are they the same molecule?

Some proteins are "activated", like fibrinogens; they are turned into fibrins by thrombins, and then the fibrins can aid in blood clotting. Are fibrinogens and fibrins the same molecule, just in ...
1
vote
1answer
78 views

identification of species of snake

Can anyone identify this colorful snake found at Pulau Ubin in Singapore? Thanks in advance!
1
vote
2answers
62 views

Which types of hydrogen bonds are known to exist in RNA secondary structures?

I'm programming an implementation of an algorithm for pattern matching in RNA structures. The algorithm assumes the following types of base pairs: Plain: No base pairs (just the primary structure of ...
1
vote
1answer
71 views

Do cell walls prevent cancer?

To my knowledge plants do not have an uncontrolled growth disease similar to cancer. Is the function by which they avoid uncontrolled growth related to their cell wall and preventing damage to ...
0
votes
1answer
33 views

What nutrients do I lose in the water when I boil vegetables?

What nutrients do I lose in the water when I boil vegetables. Has to be some water-soluble and heat labile ones right? Which ones?
1
vote
1answer
41 views

Specifics of decussation

Beginner question here: The definition of decussation I see is the crossing through the midline of a bunch of neurons. But I was wondering if there was a little more to it than this, because I'm ...
2
votes
1answer
175 views

What kind of small insect is this?

Found in central florida in the bath tub. Its about the size of a pencil marking, very small. What is it?
9
votes
2answers
148 views

Does artificial high intensity light damage permanently dark ecosystems?

Popular science features on wildlife typically capture camera images using natural light, or high-speed exposures. This is not possible where the ambient light is extremely poor. E.g. Caves, Undersea ...
2
votes
1answer
40 views

Why do oranges in the US have a small separate part?

Why do oranges in the US have a small separate detachable part at the tip which is separate from the other pods? It looks like a tiny orange itself and has a long fiber attached to it.
2
votes
1answer
52 views

How are oranges in the US or anywhere made seedless?

How are oranges in the US or anywhere made seedless? Please explain the broad principles and not the technicalities.

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