Answer:
C. capillaries connect arteries and veins.
Explanation:
A is false, veins carry blood towards the heart.
B is false because arteries are the thickest blood vessel.
C is completely true
D is false, heartbeat is controlled by electric impulses
False- it has to be a proton to carrie an electric charge
Answer: The more active cells produce more carbon dioxide.
Explanation:
When the cells are constantly working the amount of oxygen consumed and more amount of carbon dioxide is released by the cells.
Chemo receptors in the circulatory system increases the ventilation so that more carbon dioxide can go out of the cell and more oxygen can get inside the cell.
This is because the more active cells more carbon dioxide and there is a sudden increase in the concentration of carbon dioxide which need to be corrected by the help of ventilation.
During week 2 of the menstrual cycle (day 8 to day 14 or
ovulation), estrogen levels rise until it reaches its peak. Typically, days
12-14 have the highest levels of estrogen, which causes an increase in Luteinizing Hormone, which is responsible for the release of the egg cell. If
hormone levels fail to reach its peak before day 14, ovulation is not possible
because the egg cannot be released. Pregnancy may be highly unlikely.
