The purpose of the mucus found within the respiratory system is to

a. push the cilia away from the lungs.
b. lubricate the epiglottis.
c. trap particles from the air before they reach the lungs.
d. move air through the windpipe.

i'm sorry, but can you list the answers? i cannot with something i don't know the answers to

,

chris

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.