Muscles cells contract as actin filaments slide across the surface of myosin filaments, causing the ends of the muscles cell to pull together. this process requires energy in the form of ATP. which process explains how energy is made available for muscle contraction

answer: i cant find your answer. do u have another way i can answer it for you : )

explanation:

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.