The human cardiovascular system is considered closed because
a. blood is continuously circulated in the body.
b. blood provides nutrients to organs.
c. blood collects oxygen from the lungs
d. there are no holes for blood to enter or leave the system

Pentane with molecular formula c5h12, exists in three isomeric forms. one shows linear carbon chains, another has one -ch3 groups present on the third carbon atom, and the third has two -ch3 groups present on the second carbon atom. what types of isomers are these? a. geometric isomers b. structural isomers c. halotropic isomers

This is the process of making a prediction based on the results of prior observations of similar events.

What is the starting point in replication called