Quotes About Biology

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

The chances of a 1,055-sequence molecule like collagen spontaneously self-assembling are, frankly, nil.

When they are not eating, rats are likely to be having sex. Rats have a lot of sex—up to twenty times a day. If a male rat can't find a female, he will happily—or at least willingly—find relief in a male.

As Davies puts it, "If everything needs everything else, how did the community of molecules ever arise in the first place?

if you make monomers wet they don't turn into polymers—except when creating life on the Earth.

Where body meets air, we are all cadavers. These outer skin cells are replaced every month. We shed skin copiously, almost carelessly: some twenty-five thousand flakes a minute, over a million pieces every hour. Run a finger along a dusty shelf, and you are in large part clearing a path through fragments of your former self. Silently and remorselessly we turn to dust.

As Siddhartha Mukherjee observed in The Gene: An Intimate History, humans don't actually reproduce at all.8 Geckos reproduce; we recombine.

your atoms don't actually care about you - indeed, don't even know that you are there. They don't even know that they are there. They are mindless particles, after all and not even themselves alive. (It is a slightly arresting notion that if you were to pick yourself apart with tweezers, one atom at a time, you would produce a mound of fine atomic dust, none of which would have ever been alive but all of which had once been you.)

like physics before it," Woese wrote, "has moved to a level where the objects of interest and their interactions often cannot be perceived through direct observation." In

Wallace, King and Sanders point out in Biology: The Science of Life (that rarest thing: a readable textbook)

the atoms that so liberally and congenially flock together to form living things on Earth are exactly the same atoms that decline to do it elsewhere.

Water is everywhere. A potato is 80 percent water, a cow 74 percent, a bacterium 75 percent. A tomato, at 95 percent, is little but water. Even humans are 65 percent water, making us more liquid than solid by a margin of almost two to one.

Each one carries a copy of the complete genetic code—the instruction manual for your body—so it knows not only how to do its job but every other job in the body.

To be here now, alive in the twenty-first century and smart enough to know it, you also had to be the beneficiary of an extraordinary string of biological good fortune.

Proteins can't exist without DNA, and DNA has no purpose without proteins. Are we to assume then that they arose simultaneously with the purpose of supporting each other? If so: wow.

You have at least 200,000 different types of protein laboring away inside you, and so far we understand what no more than about 2 percent of them do.

To get from "protoplasmal primordial atomic globule" (as Gilbert and Sullivan put it) to sentient upright modern human has required you to mutate new traits over and over in a precisely timely manner for an exceedingly long while.

The tiniest deviation from any of these evolutionary imperatives and you might now be licking algae from cave walls or lolling walrus-like on some stony shore or disgorging air through a blowhole in the top of your head before diving sixty feet for a mouthful of delicious sandworms. Not

Look at yourself in the mirror and reflect upon the fact that you are beholding ten thousand trillion cells, and that almost every one of them holds two yards of densely compacted DNA, and you begin to appreciate just how much of this stuff you carry around with you.

It isn't easy being an organism. In the whole universe, as far as we yet know, there is only one place, an inconspicuous outpost of the Milky Way called the Earth, that will sustain you, and even it can be pretty grudging.

humans are in the domain eucarya, in the kingdom animalia, in the phylum chordata, in the subphylum vertebrata, in the class mammalia, in the order primates, in the family hominidae, in the genus Homo, in the species sapiens.

The wonder of cells is not that things occasionally go wrong, but that they manage everything so smoothly for decades at a stretch.

Typically a cell will contain some 20,000 different types of protein, and of these about 2,000 types will each be represented by at least 50,000 molecules.

clearly no thinking presence behind any of the actions of the cells. It all just happens, smoothly and repeatedly and so reliably