Answer:
The heart is a pump, usually beating about 60 to 100 times per minute. With each heartbeat, the heart sends blood throughout our bodies, carrying oxygen ... It sends out an electrical signal to start the contracting (pumping) of the heart muscle.
Explanation:
The Right Answer Is Exoskeleton.
Physical Change, although the answer is widely disputed.
Amylase breaks down starches and carbohydrates into sugars. Protease breaks down proteins into amino acids.
Variation- Heritable differences that exist in every population are the basis for natural selection
Overproduction- Competition for resources for resources
adaptation- A trait that helps an organism survive and reproduce
decent with modification- Natural Selection will result in species with adaptation that are well suited for survival and reproduction.
