Which of the following is true about compounds
a) they are groups of animals
b) they are in a fixed ratios
c) they have the same function
d) they are called "pathogens"

Providing immunity by injecting the body with a weakened form a pathogen is known as

Which would be an adaptation in a rainforest, but not in a tundra? a. ability to store water for a long time b. fur that blends in with snow c. strong claws for killing prey d. a beak that can dig into thick trees

Nucleic acid certain protein cell membranes certain carbohydrates