Quotes About Physiology

The general framework of the body is built up mainly of a series of bones, supplemented, however, in certain regions by pieces of cartilage; the bony part of the framework constitutes the skeleton.

A face isn't an organ, like a liver or a heart. A face is muscles, nerves, bones, and skin. A face is more like a hand or a foot.

When we talk about emotion, we really talk about a collection of behaviors that are produced by the brain. You can look at a person in the throes of an emotion and observe changes in the face, in the body posture, in the coloration of the skin and so on.

If a potato can produce vitamin C, why can't we? Within the animal kingdom only humans and guinea pigs are unable to synthesize vitamin C in their own bodies. Why us and guinea pigs? No point asking. Nobody knows.

We have body clocks not just in the brain but all over—in our pancreas, liver, heart, kidneys, fatty tissue, muscle, virtually everywhere—and these operate to their own timetables, dictating when hormones are released or organs are busiest or most relaxed. Your reflexes, for instance, are at their sharpest in mid-afternoon, while blood pressure peaks toward evening. Men tend to pump more testosterone early in the morning than later in the day.

Well, you blink fourteen thousand times a day—so much that your eyes are shut for twenty-three minutes of every waking day.

Of every 200 atoms in your body, 126 are hydrogen, 51 are oxygen, and just 19 are carbon32.fn3

Somebody needs to explain to me why it is that the one thing your body can suddenly do well when you get old is grow hair in your nose and ears. It's like God is playing a terrible, cruel joke on you, as if he is saying, "Well, Bill, the bad news is that from now on you are going to be barely continent, lose your faculties one by one, and have sex about once every lunar eclipse, but the good news is that you can braid your nostrils.

You discard about a hundred billion red blood cells every day. They are a big component of what makes your stools brown.

The biggest component in any human, filling 61 percent of available space, is oxygen. It may seem a touch counterintuitive that we are almost two-thirds composed of an odorless gas.

Put another way, the amount of electricity going on within your cells is a thousand times greater than the electricity within your house. You are, in a very small way, exceedingly energetic.

How fast a man's beard grows, for instance, is partly a function of how much he thinks about sex (because thinking about sex produces a testosterone surge).

One reason chimps can't talk is that they appear to lack the ability to make subtle shapes with tongue and lips to form complex sounds.

as horripilation but more commonly as getting goose bumps. In furry mammals, it adds a useful layer of insulating air between the hair and the skin, but in humans it has absolutely no physiological benefit and merely reminds us how comparatively bald we are. Horripilation also makes mammalian hair stand up (to make animals look bigger and more ferocious), which is why we get goose bumps when we are frightened or on edge, but of course that doesn't work very well for humans either.

the slight evolutionary change that pushed man's larynx deeper into his throat, and thus made choking a possibility, also brought with it the possibility of sophisticated, well-articulated speech.

When you put your hand on a hot plate, your Ruffini corpuscles cry out. Merkel cells respond to constant pressure, Pacinian corpuscles to vibration. Meissner's

Children do much better with extreme cold than with extreme heat. Because their sweat glands aren't fully developed, they don't sweat freely as adults do.

It has been calculated, and goodness knows how, it must be said, that during the course of a lifetime the heart does an amount of work sufficient a one ton object 150 miles into the air. It is a truly remarkable implement. It just doesn't care about your love life.

Por ejemplo, cuando hacemos ejercicio de forma vigorosa, la hipófisis segrega endorfinas en el torrente sanguíneo. Las endorfinas son las mismas sustancias químicas que se liberan cuando comemos o mantenemos relaciones sexuales. Están estrechamente emparentadas con los opiáceos; de ahí que a menudo se hable de la llamada «euforia del corredor

As Jablonski has written, "The loss of most of our body hair and the gain of the ability to dissipate excess body heat through eccrine sweating helped to make possible the dramatic enlargement of our most temperature-sensitive organ, the brain." That, she says, is how sweat helped to make you brainy.

Thirst, curiously, is not a reliable indication of how much water you need. People allowed to drink all the water they want after getting very thirsty usually report feeling slaked after drinking only one-fifth the amount they have lost through perspiration.

The liver was long thought to be the seat of courage, which is why a cowardly person was deemed "lily-livered.

The stomach holds about one and a half quarts, which is not very much compared with other animals. The stomach of a big dog will hold up to twice as much food as yours does.

Almost no one ever notices it, but our thumbs are on sideways. The thumbnail faces away from the rest of the fingers.