a week circulation strengthens into a _ ,and can develop into a _
Answers
Answer:
Some changes in the heart and blood vessels normally occur with age. However, many other changes that are common with aging are due to modifiable factors. If not treated, these can lead to heart disease.
BACKGROUND
The heart has two sides. The right side pumps blood to the lungs to receive oxygen and get rid of carbon dioxide. The left side pumps oxygen-rich blood to the body.
Blood flows out of the heart through arteries, which branch out and get smaller and smaller as they go into the tissues. In the tissues, they become tiny capillaries.
Capillaries are where the blood gives up oxygen and nutrients to the tissues, and receives carbon dioxide and wastes back from the tissues. Then, the vessels begin to collect together into larger and larger veins, which return blood to the heart.