Based on the data in Table 18-1, which of the following primates has the most recent common ancestor with humans?

Genes are precisely copied during the process of DNA replication and never undergo any change

a. True b. False

Tetanus results from a state of maximum muscle relaxation, which is necessary to allow the muscle to rest before the next contraction

Indicate whether the statement is true or false

By which one of the following methods is a stronger stimulus coded by neurons differently from a weaker stimulus?

A) A stronger stimulus results in greater depolarization. B) A stronger stimulus results in more action potentials/unit time. C) A stronger stimulus results in faster traveling action potentials. D) A stronger stimulus results in hyperpolarization of the neuron. E) A stronger stimulus results in prolonged influx of Na+ ions and a delay before repolarization.

Which organisms obtain heat primarily from the external environment?

a. endotherms b. ectotherms c. exotherms d. isotherms