What is a fossil?

the remains of an animal or plant preserved within a layer of rock

a large body of compacted ice formed over thousands of years

the energy radiated from the Sun

a change in the structure of Earth's surface

Why is the cell membrane so important for maintaining homeostasis

Both bacteria and amoeba are uncelluar

What four types of macromolecules

Identify which molecule or element is described below

Wich organelle is responsible for energy production in the cell?

Why is an organism's niche like a person's occupation? A) An organism makes "money" by working in its niche. B) A niche is a "company" that the organism has to work in. C) A niche is a "factory" where organisms build things.

After eating a carbohydrate-rich meal, the mammalian pancreas increases its secretion of * glucagon O throxine insulin oxytocin

2. The heart is classified as a (n)

How long does it take for cocaine to leave out your Stream

Why is the tundra treeless? lack of sufficient water permanently frozen ground winters too harsh too many fires