Answer:
D) four.
Explanation:
The two atria hold the blood that circulates away from the heart. The heart has four one-way valves, which open and close with each heartbeat. The tricuspid valve and the mitral valve are located between the atria and allow the blood to flow from the atria to the ventricles. Also you don't have to but mind marking Brainliest?
Yes it alters the levels of neurotransmitters
The lens of the eye loses its ELASTICITY with age and cannot change from viewing distant objects and close objects as readily as before.
Maybe you have pinworms?? go to the doctor asap!!!!
Answer:
Oh boy, here we go again.
Explanation:
Go kill Claire