Which part of the cell is semipermeable, or controls what enters and leaves the cell? a: mitochondrion b: cytoplasm c: endoplasmic reticulum d: cell membrane

Which is a genetic engineering advancement directly related to a career in biotechnology? 1) improving solar energy collection 2) transporting textiles at higher rates 3)creating crop foods that resist insect pests 4)repairing historical sites with quality materials

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

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above