The involuntary wave of contractions that keep food moving in one direction is called ___. a.
absorption
b.
peristalsis
c.
esophagus
d.
none of the above

Please select the best answer from the choices provided

A
B
C
D

During the process of meiosis, special cells called gametes are formed. gametes only have half the number of chromosomes that the other cells in the body have. what form of reproduction do organisms that produce gametes use?

Compare and contrast region e in the illustration above with region d. describe the physical characteristics of each region.

What sentence best supports the statement that hormones are involved in the regulation of homeostasis? a. the hormone erythropoeitin increases the production of red blood cells when oxygen levels are low. b. the hormone oxytocin promotes labor contractions of the uterus during childbirth. c. the hormone melatonin induces sleep and its production is slowed by exposure to light. d. the hormone cortisol suppresses the immune system and is produced when the body is under stress.