Why cant animals grow back parts of their body

When a person is exercising the body needs to deliver increased amounts of oxygen to the muscles which component of blood ensures that the muscles will receive it

High blood pressure occurs when there is too much blood flowing through the blood vessels at one time. by changing the amount of water in the blood, blood pressure can change. the excretory system can to lower blood pressure.which would most likely occur in the kidney? a)more water would be transferred from the nephron.b)less water would be absorbed into the nephron.c)the amount of water in the bladder would decrease.d)the amount of water in the blood would increase.

You have trained year for a marathon. in your first attempt to run a marathon, you decide that you want to complete this 26-mile race in 4-5 hours. a. what is the length of a marathon in kilometers (1mile= 1.6 kilometers). b. what would your average speed have to be to complete the race 4.5 hours? give your answer in kilometers per hour.