What are two ways new species of organisms can be introduced in an ecosystem?

How many years would it take the atlantic ocean to grow 500 centimeters? show your work.

Which statement describes a way in which the digestive and excretory systems work together? a. the nephrons absorb nutrients from food going to the large intestine. b. the excretory system balances blood gases in the small intestine. c. the intestinal villi filter blood and send wastes to the bladder. d. the excretory system balances the salts and water obtained from digested food

Gram-negative bacteria have a cell wall that is! and does not accept the stain, making itappear