Defecation
a. is initiated by distension of the wall of the colon.
b. depends on voluntary control of the external sphincter of the anus.
c. depends on the motor impulses from sympathetic pathways.
d. decreases pressure in the rectum.

Identify characteristics of energy from the sun. check all that apply. almost all of the energy on earth comes from the sun. energy from the sun is known as mechanical energy. the energy in fossil fuels originally came from the sun. plants convert the energy of sunlight into chemical energy.