A membrane helps protect the cell
I think the most involved would be your circular system because since your running fast you need to pump blood. Your muscular system because your moving a lot and your respiratory system because you need more oxygen
ANSWER: A. Exercise is important for the body to function properly.
Exercise deliver adequate amounts of oxygen and remove waste from body tissues by regulating nervous, respiratory, circulatory and hormonal systems in the body. During exercise, body tissues and other metabolic processes in the body requires oxygen.Low levels of oxygen and higher levels of carbon dioxides are mainly detected by sympathetic division of the autonomic nervous system which control the physical activity of the body by increasing heart rate, blood pressure and respiration as a result of this there is an increase in the amount of blood pumped per minute by the heart and oxygenated body gets distributed to the tissues. This also involves release of glucose by the liver as an energy reservoir to control the level of blood glucose pancreas secrete insulin hormone , thyroid gland is also stimulated in response to increase heart rate.
Kidney is your answer that's easy like 2+2 it equals 16
Umbilical vein transports blood rich in oxygen and nutrients from the placenta to the fetus. The unpaired umbilical vein is a vein present during fetal development and it transports the nutrient- and oxygen-rich blood from the placental villi via the umbilical cord to the embryo. The umbilical vein is connected to the two intraembryonic umbilical veins.
