Where does most of the primary production occur in an ocean ecosystem? a. first 75 feet b. first 150 feet c. first 100 feet d. first 200 feet

Cells destroy body cells infected by a virus or bacteria. killer t t memory t none of the above

Select the correct answer. which mutation is harmful to the organism? a. a mutation allowing moths to camouflage better on blackened tree bark b. a mutation making staphylococcus aureus resistant to the antibiotic methicillin c. a mutation inhibiting human immunodeficiency virus from attaching to and entering the cell d. a mutation causing uncontrolled cell division e. a mutation giving plant leaves a bitter taste to discourage herbivores from eating them

In order for you to hold your breath, your nervous system must send messages to your a. respiratory system b. digestive system c. heart in your cardiovascular system d. check in your muscular system