The heart valves actually touch the flowing blood, therefore they are

Name the glands associated with human digestive system

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen

How did the club fungi get its name? a. it is named for the club-shaped seeds it produces. b. it is named for the way individual species grow together in small groups called “clubs.” c. it is named for the club-shaped area where it produces spores. d. it is named for the club-like mechanism it uses to kill its prey.