Clonal selection of lymphocytes leads to the development of which type of cells? a. effector cells and b cells b. t cells and memory cells c. effector cells and memory cells

The sketch shows a rynchosaur, an extinct animal that is known only from fossils. there has been much debate about the classification of these creatures. some scientists suggest that they belong with primitive amphibians, and some think they are related to snakes and lizards.the data equally support both cases. which statement best explains how to draw a cladogram that includes the rynchosaur? draw the cladogram for amphibians. draw the cladogram for reptiles. draw two cladograms, both showing the traits, and leave it as a hypothesis. draw two cladograms, both showing the traits, and have scientists vote

How do you date a sample of rock that you suspect as being one of the earliest on earth

The cluster of developing cells from conception until birth is called an