Smart Art: Biology

Biology Basics: A primer on biology

Biology is the study of life. That brings us to the question, what is life?

To be classified as a living thing, an object must meet six conditions:

1. Consists of cells (or is a single-cell organism).
2. Has a complex chemistry (large, complex molecules being acted upon).
3. Grows and develops (Alec Baldwin is granted an exemption, here).
4. Responds to the environment (members of Congress are granted an exemption, here).
5. Reproduces (or its species is capable of same).
6. Maintains homeostasis (that is, the cellular processes maintain a certain setpoint or balance).

We will use the term "theory" here. Note this does not mean "unproven idea." In science, "theory" means a way of explaining something. This same meaning exists in other venues, for example a technical manual will provide the "theory of operation" of  device.

Biology has four unifying principles:

1. Cell theory. This theory basically holds that all living things are made up of cells and living cells come from other living cells. All living things start as a single cell, and some living things are single-celled. A bacterium is a single-celled organism. A virus is not a living thing, so don't confuse viruses and bacteria.
2. Gene theory. This theory basically holds that genes provide the control instructions for living things. Genes are why, for example, a cat doesn't give birth to a horse and why different species exist.
3. Homeostasis. This word literally means "staying the same." Your body, for example, looks like a human body and doesn't morph into that of a goat. Maybe on rare occasions you smell that way, but that's another issue.
4. Evolution. This principle underlies nearly every scientific discipline and every body of engineering. People who "don't believe in evolution" are adopting an untenable position. Evolution is what happens when characteristics change over time. In the case of living things, this tends to be a long time. Though not always. Bodybuilders seek the adaptive response, and the timeframe is on the order of days rather than eons (but the adaptations are correspondingly smaller). The theory of evolution is not "man came from monkeys." It's actually a detailed body of science that several volumes could cover and still have room for discussion, facts, and analysis. But the basic premise is things adapt or die.

All living things depend upon their environment. Indeed, they adapt (or die) to fit that environment. It's what supplies them with fuel (food and, in our case, oxygen), water, and shelter. Living things may cooperate (symbiosis) or compete with each other for these resources. Living things may also cooperate for protection, for example small animals that eat parasites off of big animals in exchange for not being eaten by other animals.

An aspect of biology that confounds many students, initially, is organic chemistry. While it is complex, it's worth studying and it makes the basis for understanding biology. Many college degrees require at least one organic chemistry course, for this reason. You begin by studying elements then compounds. Then you look at organic molecules and how they interact with living things. It's there that many students really get confused. The key to overcoming that is to go back to the basics of elements and compounds. So you have to pay attention from square one and learn the material. If you do that, you won't get confused later.

You are already familiar with three broad classifications of organic compounds because diet books yammer on about these incessantly: fats, carbohydrates, and proteins. And you also know about the fourth classification, nucleic acids. So don't let biochemistry intimidate you. Enjoy your study of life and how it works in all its diversity.