Because while you're preagant your have so much presure on it it doesnt have a choice where as weight gain everything grows with it. Think of it this way, if you've ever felt a pregants womans belly its harder than usual. If you touch someones belly that is bigger its more smoshy (I know thats not spelt right)
Red blood cells are responsible for the distribution of oxygen to other cells in the body.
Answer:
The endocrine system secretes hormones into blood and other body fluids Hormones provide feedback to the brain to affect neural processing. Reproductive hormones affect the development of the nervous system.
Explanation:
Temperature difference and Earth's tilt
