During which period did the first fish evolve?

Cambrian

Ordovician

Devonian

none of the above

Yeast are a type of organism that can do both aerobic and anaerobic respiration, depending on whether or not oxygen is available. A scientist does an experiment on two identical populations of yeast.

Which of the following statements best describes a function of adaptive immunity? A. If serves as the first line of defense in a body. B. It regulates equilibrium between immune system processes C. It regulates inflammation in the body D.

What would happen to a neuron if it was exposed to tetrodotoxin?

During gaseous exchange terrestrial mammals breathe in (A) air and breathe out carbon dioxide (B) oxygen and breathe out carbon dioxide (C) air with with a high concentration of oxygen and breathe out carbon dioxide (D) air with a high concentration

When the nurse researcher conducts an electronic literature search, the search yields more than 7000 citations for the topic. the researcher should make which of these interpretations of the finding?

Which will have a better chance of surviving a major change in the environment where it lives: A) A bacteria strain with only twenty minutes between generations B) A large mammal (like bears) with decades between generations Explain your choice

What are the three-letter "words"of mRNA

What are the two ways that carbon enters into the atmosphere?

If an animal cell is placed in distilled water, it will A) remain the same size. B) shrink. C) swell and eventually explode. D) swell, but stop when the cell wall prevents further expansion.

What atre three types of nerve fibers?