Which describes how blood can be protective in nature?

Which statement best describes a keystone species? o a. it has littlelmenetic variation. it has an extremely high population. 0 b. 0 c. it remains unaffected by all environmental changes. od. it has a strong influence on the ecosystem. 0 e. it's the first species to populate a new ecosystem.

What do all macromolecules have in common with each other? oa. they all are formed from the same elements.ob. they all have major roles in cell membranesoc. they all act as catalysts in the body.od. they all have peptide bonds between carbon atoms.

The idea that all living things are made up of cells is considered scientific law. this means the idea is an emerging scientific idea that has a logical explanation. has been tested with similar results at least twice. is supported by scientific consensus and a large amount of evidence. has been rejected only once by the scientific community