What is a negative feedback mechanism? Explain an example.

What is a positive feedback mechanism? Explain an example.

A negative feedback mechanism is a regulatory mechanism in which a stimulus causes an opposite output in order to maintain an ideal level of whatever is being regulated. Example: osmoregulation. A positive feedback mechanism is a process in which the end products of an action cause more of that action to occur in a feedback loop. Example: childbirth.

carbohydrates: (starches and sugars) composed of carbon, hydrogen, and oxygen.

lipids: (fats, oils, and waxes) are made of carbon and hydrogen atoms.

nucleic acids: contain hydrogen, oxygen, nitrogen, carbon, and phosphorus. they are polymers of nucleotides. a nucleotide has three parts, a 5-carbon sugar, a phosphate     (-po⬇️4) group, and a nitrogenous base.

proteins: made up of nitrogen, carbon, hydrogen, and oxygen. they are polymers of amino acids.

which

what is a measurement of the earth’s history divided into time periods?

> fossil record <

sedimentary rock

> geologic time scale <

radioactive elements