The diagram shows embryo development of four different animals. how is this evidence used to suggest that life changes over time? a. lack of homologous structures in later stages of embryonic development indicate that each species is unique, and a common ancestor is unlikely. b. similarities in embryonic development prove that vestigial structures are common to all species, and life has changed very little over time. c. when there are physical similarities in the early stages of embryonic development, it suggests that each of the modern organisms once had a common ancestor. d. the genetic inheritance of each of these species is exactly the same in the early stages of development but then changes as the embryo grows and develops over time.

Are the earth's ocean floor and continents the same age geologically? why or why not?

Which type of transport is responsible for oxygen entering into blood cells? a. vesicle b.passive c. facilitated d.active b.passive

Which of the following statements is correct in hour our immune system responds to a potential pathogen? a. the adapted immune system will call on the innate immune system to destroy the pathogen. b. b cells will start reading the antigen code immediately and call t cells to assist in destroying the pathogen. c. the skin will be the first line of defense, and then the many phagocytes in the bloodstream will attempt to consume the possible pathogen. d. the t-cells in the adapted immune systems are the first to recognize the pathogen vaccines are weakened forms of disease causing microorganisms, which are given to patients to prevent disease. after the vaccine is administered, the immune system responds by creating a(n) to recognize the a. antigen, antibody b. antibody, antigen c. antibody, antibiotic d. antibiotic, antibody