The both decrease genetic variation
Humans are horrible to each other and always will be
Answer:
True. The heart contracts twice per heartbeat. One contraction is the ventricular and the other one is the artrial.
Answer:
Option 2, Arousal
Explanation:
Reticular activating system (RAS) or the ascending arousal system consists of nuclei and tracts and is involved in the regulation of wakefulness, sleep aspects and arousal.
RAS is located in the mesopons and interacts with the basal forebrainand thalamocortical systems. It activates the cerebral cortex and thereby maintain the consiusness. The neurons located at the pontomesencephalic junctionparticipates in this activity of arousal.
Hence, option 2 is correct
