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7

This is quite common. It is most likely dried rheum (also know by slang terms such as "sleep", "eye boogers", "eye crusties", etc.). Rheum is the result of dried mucus, tears (and the salt and minerals therein), as well as dead blood and skin cells. Essentially it is all the stuff that’s normally in your eye that eventually dries up making the contents ...


7

As @terdon comments, dormant organisms can survive in vacuum. This includes lichens, bacteria, and even an animal: the ever-amazing and adorable tardigrade (Jönnson et al 2008). In 2006, tardigrades survived exposure to the vacuum of outer space with no appreciable difference in mortality compared to controls. Tardigrade Hypsibius dujardini, a different ...


6

This is really the most fundamental concept of cell biology, so good question. If you look at the size of the cells of a whale and compare them to the size of the cells from a mice, they are the same. There is a reason why cells are small, and it has to do with the fact they survive based on their ability to absorb enough nutrients from their environment. As ...


5

The dynamic-dominance hypothesis of handedness states that the essential factor that distinguishes dominant from nondominant arm performance is the facility governing the control of limb dynamics. Sainburg (1) writes that It should be noted that dominant arm advantages do not apply to all tasks, or all aspects of tasks. Healey et al. (1986) examined an ...


5

In men, gout is associated with a higher risk of death from all causes. This would imply that their life expectancy is shorter. From a review by Kim et al. (1): Among men who did not have pre-existing coronary heart disease, the increased mortality risk is due primarily to an elevated risk of cardiovascular death, particularly from coronary heart ...


4

Your question supposes a very linear version of the flow of stomach contents of: 1->2->mouth->3->4 In reality, it is not so linear. Firstly some background: The rumen and reticulum form the first two parts of the four, and are in fact a single chamber/organ (collectively known as the reticulorumen). They have different wall structures, and perform initial ...


3

The functional implications of the biconcave shape of human red blood cells are not fully understood. Several hypotheses have been suggested as explanations, including bending energy (1) and effects on oxygen transport (2). More recently, it has been hypothesized that the shape is important for the flow properties of the blood cells in capillaries. Uzoigwe ...


2

The SA node is not necessary for contraction of the heart. The reason that this works is exactly what you mentioned: schematics. They are in sequence, but within that sequence, there are multiple autonomous signal generators in the heart, where spontaneous depolarization occurs to initiate contraction: the SA node, the AV node, and the purkinje fibers. ...


2

What you're referring to as a mosquito bite is actually the "wheal" (red swollen bump in the skin) that forms from an immune system reaction to antigens (foreign molecules) in the saliva of the mosquito that it leaves behind inside the bite. It's not technically a toxin, just something that causes an immune reaction. It's also not an infection, it's ...


2

I'm not sure if why is referring to the biological basis or the reasoning for why it is beneficial but I've briefly summarised both. If you'd like more detail just accept and ask again clarifying your exact interest in this broad question. Pain is taken up through the spinothalamic pathway but at may opportunities it may be blocked. It may be blocked by ...


2

Not sure it is proven, but this paper makes use of the assumption: West et al, PNAS 99:2473, http://www.pnas.org/content/99/suppl_1/2473.full Btw, this paper may be relevant for you as it focuses on the metabolic activity, which is not quite propotional to body mass (power 3/4: it's growing slower)


1

Unique and interesting question. It's hard to give a firm "why," but we can discuss the ways that the ear and other "holes" differ. Mucous membranes line every tract into/out of the human body. Technically the ear is not a point of entry, as the tympanic membrane makes the external auditory canal a sort of blind pouch. The skin lining the ear is ...


1

First thing to make clear is that net $6$ $H_2O$ go out of the reaction.($12$$H_2O$ $-$ $6$$H_2O$) Let me tell you my calculation, you should then be able to figure out what went wrong. For the Left hand Side, $6$ $H_2O$ are accounted here : $2$ $H_2O$ go in conversion of 2-Phosphoglycertae to phosphoenolpyruvate. $2$ $H_2O$ in TCA from conversion of ...


1

The name used frequently for this phenomenon is "Post-lunch dip". "The post-lunch dip is a real phenomenon that can occur even when the individual has had no lunch and is unaware of the time of day. This dip has its roots in human biology, and may be linked to the size of the 12-hour harmonic in the circadian system. It is certainly exacerbated by a ...


1

There are regulatory mechanisms that may prevent moderate hypoglycemia to progress to a more severe state, however these mechanisms act before lack of conciousness sets in. The progression of hypoglycemia may depend on overall health and medical status and vary between healthy and diabetic persons, for example. Rosenthal et al. (1) write that The brain ...



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