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Because mammary glands define us (mammals), the genetics of the ability to make milk has been of interest.[1] Because we consume milk, we have a dairy industry. Because the industry places a monetary value to certain milk constituents, the genetics of milk component production has been a viable area of study[2]. Since you are talking of cream production, ...


6

This question is at least two questions. Dividing cells In terms of a dividing human cell line, every time a division occurs the telomeres capping the ends of the chromosomes get a little bit shorter. Once the telomeres get short enough they act as a signal that triggers apoptosis, destroying the cell. There is some human-to-human variation in the initial ...


6

1) A hot bath, or soak in hot water raises our body temperature. Several benefits of this rise include: Improved blood circulation, Improved lymph circulation, detoxification, increased metabolism and calmer nervous system. 2) As our body temperature rises we sweat. Sweating helps to bring toxins to the surface of our skin so they can be eliminated through ...


6

I think this question has more to do with kinetics / transport phenomenons than biology, but that's okay, everything is connected especially my computer to the internet. ;-) The basic idea behind transport phenomenons is that there will always be a flux of quantitative properties (e.g. charges, particle number, entropy, volume, etc...) where the qualitative ...


5

I think inf3rno's answer is very complete, so I will just be adding some notes that might help OP understanding what's happening. Say that we increase the intracellular concentration of potassium by 10 mM, a +1 valence ion which contributes to POSITIVE membrane potential. Let's say we do that, in an in vitro cell model, using a syringe with only K⁺ ...


4

Prions are misfolded proteins with abnormal tertiary or quaternary structures. That grants them resistance (to some extent, at least) to proteases (1). Also researchers believe that prions are able to replicate (2), by changing the structure of other proteins. Regarding the gastrointestinal barrier, that isn't exactly true. It has been shown that small ...


3

In general I'd say "left and right brained behaviour" is total nonsense. I guess the origin of this kind of claim is a bad press release or something. Let's start with something simple. Say hearing. When you hear a sound to your left ear, it is projected strongly to the contra-lateral side (right hemisphere), and weakly to the ipsi-lateral (left hemisphere) ...


3

Check out Van Der Pol (chaotic) oscillator. It can be used to model heart rhythms. If a stimulus is applied to the oscillator, it will return to the curved envelope discussed in the article. However, if "pushed just right", the oscillator's current state will be pushed towards the very center of the loop, and it will stop oscillating. This is the mechanism ...


3

Anti-oxidants affect human metabolism by altering the redox states of the cell and redox-regulated functions and signaling mechanisms. The following quotes are from The Redox Stress Hypothesis of Aging (Free Radic Biol Med. Feb 2012) More recently, in a major conceptual shift, ROS have been found to be physiologically vital for signal transduction, ...


3

Yes, humans do have the hyaloid canal. Schematic diagram of the human eye (reference) For function and other information, please refer to this journal article.


2

Chris is right, I just want to extend his answer a little bit more. The presence of corrosion and the corrosion speed highly depends on the concentration of the acid, which is very low (0.5% according to Chris) in this case (considering that ccHCl is about 35-40%). According to wikipedia the vapour pressure of water is about 2645 kPa while the vapour ...


2

This is a draft. How do the pharmacodynamics of the NSAIDs differ - -? Merck's manual ch. 36 to start little bit at an introductory level: The anti-inflammatory activity of the NSAIDs is mediated chiefly through inhibition of biosynthesis of prostaglandins (Figure 36–2). Various NSAIDs have additional possible mechanisms of action, including ...


2

Hepatitis is a condition of the liver where the cells of the liver organ are inflamed. Most often it is caused by a viral infection, hepatitis A, B and C are all viral forms of the disease. Bacteria (and Fungi) can cause hepatitis of the liver, and two examples would be the Staphylococcal and Streptococcal bacteria. These can directly infect the liver, and ...


2

Afaik you can describe the potentials between the two sides of the cell membrane using the Nernst-equation. Yepp wikipedia writes the same here. Membrane potential is a very important thing, because human cells require stable internal concentrations of Na+, K+, Ca2+, etc... in order to work properly. These concentration can depend on species, for example ...


2

What you might be experiencing is olfactory fatigue, the temporary, normal inability to distinguish a particular odor after a prolonged exposure to it. It's a form of neural adaptation, a change over time in the responsiveness of the sensory system to a constant stimulus. This adaptative mechanism might prevent the overloading of the nervous system. ...


2

That "red pulp" spaces you're referring are not blood vessels but, in fact, thyroid follicles that selectively absorb iodine from the blood for production of thyroid hormones and storage of thyroglobuline. So, they act as a reservoir of the materials used by the thyroid's epithelial cells, also called follicular cells, to produce thyroid hormones (T3 and ...


2

TL;DR the huge block of text: The innate immune system only recognizes certain antigens, called PAMPs. The activate immune system usually requires the immune system, but it can get around this in some cases. You're on the right track. Pathogen-associated molecular patterns (PAMPs) Innate immune cells such as macrophages and denritic cells ...


1

The meaning of the term microenvironment depends on the scale of the system that you're looking at. It's a sort of weasel word that loosely means "context" or "stuff in the immediate surroundings of the system of interest that has some kind of an effect on it". I've seen it used to describe everything from the chemical microenvironment of a cell (e.g. a ...


1

As someone who has dabbled in both biology and programming, I assume you are referring to the theoritical ability of functional programming to simulate organic behaviour from well defined input. From that point of view, our comprehension of the human cell behaviour is currently near stone age level. The astounding diversity of homeostatic and signaling ...


1

There is an increase by abstinence. The within-subject variability of the semen sperm count (n), volume (v) and the total number of spermatozoa (N) was studied on 220 ejaculates from 36 normal subjects after an abstinence of 7 days or less. The three semen characteristics for a given subject were highly correlated with the length of ...


1

If there is passive transport for each ion, then every ion will diffuse over the membrane until the concentrations will be the same, and the membrane potential will be zero. So there is active transport in the cell, which maintains the resting potential which is -63mV. So with the current concentrations the membrane potential will differ from this -63mV, ...


1

Your vocal chords vibrate to produce a tone, but your mouth shapes that tone into the sounds that make up voice. If your vocal chords fail or are removed, the electrolarynx can be used to vibrate the throat for you, but your mouth still needs to shape that sound into words. Because the electrolarynx produces a mechanical buzzing vibration, you get mechanical ...


1

You may want to look into "Evolutionary - Developmental Biology", which deals with how an embryo develops into a grown organism. Thus, by combinatorial specifying the identity of particular body regions, Hox genes determine where limbs and other body segments will grow in a developing embryo or larva. A paragon of a toolbox gene is Pax6/eyeless, ...


1

For a bit of background, this test was devised by Nobuyuki Kayahara and it was originally thought that it shows the dominance of one part of the brain to the other. This was later on discarded as a misconception (reference). It is now widely believed that the clockwise - counter-clockwise rotation is a phenomenon called Bistable perception (Reference 1 and ...


1

I agree with Armatus, however I feel his answer incomplete. Sodium (along with chlorine) is the most important ion in the blood if we are talking about osmolarity and water transport. Water wants to move to the high osmolarity places so its transport is mainly controlled by the transport of sodium through selective sodium channels. This is not just about ...



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