What is an allele? A. A group of chromosomes
B. A gene that causes a specific trait
C. An organism that lives in Eukaryotes
D. A chromosome that determines gender

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

Guard cells control which event? the growth of plants capture of solar energy gas exchange in leaves water absorption in roots

Why did the federal government end its support of yucca mountain as a site for long-term storage of nuclear water