Plesiosaurs swam by using their paddle-like limbs in a manner similar to that of a

fish.

sea lion.

human.

none of the above

How much time has elapsed from the very beginning of "the memior of the conquistador bernal diaz del castillo" to the end? a. castillo's whole life b. a quarter of an hour c. a few weeks d. a decade

This is a situation in which genes are attached to an organism's sex chromosomes; the sex of an organism influences the expression of a gene.

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes