Match the term to the correct system.
hormones
a. immune system
fingernails b. endocrine system
sperm and egg c. excretory system
bladder d. reproductive system
killing pathogens e. integumentary system

Describe the iron sulfide hypothesis and the lipid membrane hypothesis.

The image below shows a common blood pressure gauge. what does this device do? a. measures the level of oxygen present in the blood b. measures the pressure of blood when the lungs expand and compress c. measures the electrical activity of the heart d. measures the pressure of blood when the heart contracts and relaxes

Which example describes a mutualistic relationship between organisms? young wasps prey on caterpillars. crabs eat the remains of dead fish. tapeworms feed on food in the intestines of cats ants protect a tree on which they feed.