Which of the following is not a step used by cytotoxic t cells to kill infected host cells? a)secretion of granzyme b)recognition of infected host cell using its tcr c) secreting antibody specific against the pathogen. d) secretion of perforin.

Idont understand by supporting the plant and holding the leaves up to the light. question 3 options: tap or fibrous root flower petals herbaceous or wood stems leaves with stomata

Up until 1938, paleontologists accepted the idea that coelacanths (an ancient fish) went extinct at the time that they last appear in the fossil record, about 80 million years ago. but in 1938, a live coelacanth was discovered off the coast of south africa that was compared to the fossil record and found to be the same species what goal of science does this discovery represent

Select the correct answer.what is the observable characteristic of a person called? o a. genotypephenotypeoc.alleleo d.gene