Temperature
The body must maintain a relatively constant temperature. If it gets too hot, the body employs vasodilation to cool down. This dilates the blood vessels, allowing more heat to escape from them through the skin.
Glucose
The body must regulate glucose levels to stay healthy. When glucose levels become too high, the body releases a hormone called insulin. When they become too low, the body converts the glycogen in the blood to glucose.
Toxins
Toxins in the blood can disrupt the body's homeostasis. Thus, it signals the urinary system to ensure that the toxins are excreted.
Blood Pressure
The body must maintain healthy levels of blood pressure. To do so, the brain sends signals to the heart to speed up or slow down according to the blood pressure.
pH
The lungs control the pH amount in the body. If pH levels become unbalanced, the lungs push more or less carbon dioxide out of the diaphragm. This can raise or lower pH levels in the body.
Answer:
A.
Explanation:
Human heart is an organ that is responsible for the circulation of blood throughout the body and works in a systematic pathway.
The human heart recieves blood from two large veins, the superior and inferior venae cavae and enters through different chambers in the heart that is first at right atrium to right ventricle, from right ventricle to left atrium, then from left atrium pumped into the left ventricle.
The blood first enters into arteries and than move to narrorwer to arterioles that deliver blood to capillaries of the organ where the oxygen and nutrients from blood are supplied to body cells for metabolism and the deoxygenated blood enters into veins.
Hence, the correct option is "A".
3. chemical signals!
hope that helped :)