20. what condition is required for atp synthase to move hydrogen down its gradient? a. more atp molecules ahead of the hydrogen than below it b. more hydrogen ions outside the membrane than inside it c. more hydrogen ions inside the membrane than outside it d. a day with 75 percent direct sunlight

B

Explanation:

This H+ ion gradient is referred to as a proton motive force. It is  created using energy from the Krebs cycle in the matrix of the mitochondria. As electrons are passed from one protein complex to another, reducing molecules such as NADH and FADH2, the protons are pumped to the intermembrane space of the mitochondria. ATP synthase uses this potential to generate ATP as the H+ ions move downgradient (back to the matrix) through channels in the protein enzyme.  

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.

b) the inside picture would look at a very high temperature in a very low ph