How are chordates further divided into three subphyla? A. By their habitats
B. By the presence or absence of a notochord
C. By how they obtain food
D. By their body structures

Ineed to get this test done which of the following statements is correct in hour our immune system responds to a potential pathogen? a.) the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. b.) b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c.) the adapted immune system will call on the innate immune system to destroy the pathogen. d.) the t-cells in the adapted immune systems are the first to recognize the pathogen

If the rna molecule in a human has the nucleotide sequence of guu, this would the amino acid valine would be needed to make the protein. how would this cha process was occurring in a mushroom?

Which of the following is a true statement? a. individuals evolve to have adaptations. b. individuals have adaptations that can change over time. c. individuals have traits that may or may not make them successful at reproduction. d. populations cant evolve, only individual organisms.