Basic Biology test!

In biology class, be prepared to hear this word a lot. It stands in for "any single living thing."

Taxonomy is the practice of ordering living things in a scientific fashion. Nowadays, we also refer to "cladistics," which is ordering things according to their evolutionary characteristics.

There are a number of mnemonic devices that will help you remember this sequence. May we suggest the of-the-moment "Katy Perry Caught One Fine Guy Saturday"?

In scientific names, the genus is uppercased while the species is lowercased. So humans are, scientifically, Homo sapiens.

"Base pairs" are the rungs in the DNA ladder. You'll see a more specific question about that "ladder" elsewhere in this quiz.

Air resistance is a common term in physics. All problems involving motion have to account for it, unless they take place in a vacuum (or that ideal Physics 101 environment where the professor says, "You don't have to worry about air resistance for this one.")

We feel for you if you chose "deoxynucleic acid." It seems like the syllable "ribo" should be represented by an "R," but it isn't.

Francis Crick, the co-discoverer of DNA, realized the structure of DNA in a kind of "lightning bolt" of inspiration. Overwhelmed with excitement, he burst into his house, the story goes, and asked his wife to draw a twisted ladder as he described it to her. (Apparently, she was the better illustrator of the two).

Glucose is simple sugar, or blood sugar (when it's in the bloodstream). The other four elements are molecules in base pairs of DNA.

Osmosis is the process in which water moves from areas of high density to low density. This allows it to move in and out of cells.

Antibiotics kill bacteria, not viruses. This is important, because the pointless use of antibiotics against viruses is one of the things which has led to antibiotic-resistant bacteria, or "superbugs."

Carl Linnaeus was a Swedish zoologist and botanist. He created the narrowing classification system we all learn in middle school, down to "genus" and "species."

Just as the body has organs, the cell has organelles. Like organs, they are biologically active, not just inert, as the cytoplasm is.

The nucleus is a bit like the "brain" or "command center" of the cell. There, you'll find a complete set of chromosomes for the entire organism. That's why cloning is possible from just one cell. Amazing!

Mitosis is cell division, or birth. Apoptosis is cell death, and when it happens at higher rates than expected, it's a sign that something is very wrong in the body.

Mitochondria break down nutrients and create ATP, or adenosine triphosphate, a power source. Mitochondria also contain some DNA, which is why you'll hear about forensic scientists using mitochondrial DNA for testing when nuclear DNA has not survived at a crime scene.

This has become a lot easier to remember since the advent of the gene-testing serivce "23 and Me"!

"Motile" is just a fancy word for "capable of movement." Sperm cells have a special tail-like projection that makes them motile.

"Homeostasis" means "situation normal" for the body, like the temperature being about 98.6 degrees (give or take). Illness and injury make homeostasis hard to maintain.

Bacteria are prokaryotes. They are very simple organisms, yet can be very hardy, and sometimes destructive.

"Biome" isn't exactly easy to define. Think of it like a climate, but with more factors involved, especially the flora and fauna living there. Tundra, taiga, desert and rainforest are all examples.

"Pathology" is a field in medicine which, unsurprisingly, studies the causes of disease. The term "pathology" has been borrowed by psychology, where psychologists use it to describe the root and the course of a mental disorder.

Chlorophyll is the key component in photosynthesis. It gives plants their lovely green colors.

In medicine, "cytology" is the study of processes that take place at the cellular level. Lab work often involves cytology.

Cytoplasm is made up mostly of water and salt. It's a lot like vitreous humor in the eye, existing to support the parts of the cell within.

Though we think of the lungs as the place where oxygen is exchanged for carbon dioxide, this process also happens in the mitochondria of your cells. It is called the "citric acid cycle" or the "Krebs cycle," after biochemist Hans Krebs.

The prefix "ovi-" means we're dealing with eggs, and "oviparous" means reproducing via eggs. Sidenote: Is "oviphagous" a word, meaning "egg-eating"? It should be!

The playtpus breaks so many rules of taxonomy that the first European scientists to examine the cadaver of one thought it was a hoax. It is the only mammal to lay eggs, and one of the few to have venom.

The more common term for this is "warm-blooded." Humans are homeotherms, which means our bodies tend to stay at 98.6 degrees regardless of conditions around us.

"Torpor" is a kind of "hibernation lite." It helps animals to conserve energy, but they don't disappear into it for an entire season.

Far from it! Sodium is essential to conducting water into cells. When people go on extreme low-sodium diets, it can lead to hyponatremia, a type of dehydration that occurs within the body, no matter how much water that person drinks.

The interstitium went unnoticed for so long because it is a very thin membrane that wraps around body parts. How it affects the body's functions is not really known yet.

When two species have a relationship that benefits both of them, that's mutualism. An example is pollination, in which birds or bees feed off the nectar of flowers, but spread the pollen the flowers need to reproduce.

Commensalism falls between parasitism and mutualism. The host species might well *be* unaware, but the main point is that it is unharmed.

"Gattaca" was about a future world in which your genetic code -- superior, adequate or inferior -- shaped your destiny. Fittingly, the title was made up entirely of the four letters in DNA base pairs: G, A, T and C.