Which one of these exibis a notochord at some of its developments

Which is an important function of normal flora? a. aid with bone marrow production. b. crowd out pathogenic bacteria. c. destroy digestive track pathogens. d. manufacture iron in the bloodstream.

What type of appendages do sponges cnidarians roundworms annelids mollusks arthropods echinoderms and vertebrate have? jointed, not jointed, absent  

Which of the following is an example of competition a. the leaves of a tree prevent a small shrub from getting sunlight. three species of birds feed a different heights in the same tree. b. three species of birds feed at different heights in the same tree c. zebra and giraffe’s feed on different grassland plants d. cats living in two different homes eat the same brand of cat food.