How is the cardiovascular system affected by aging?

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.

Explanation:

to prevent people from getting the ebola virus, countries around the world paid to doctors develop a new vaccine. now that the vaccine has been made, doctors will need to experiment on a large number of people to find out if it works safely.

what is the greatest limitation that scientists are dealing with as they try to figure out how to experiment with the ebola vaccine?

meditation is a practice of sitting still and quiet for minutes or even hours. it has been practiced for thousands of years and is even a part of religious practices for some people. carefully controlled, repeated measurements of brain activity have shown that meditation does increase certain chemicals in the brain and even grows the part of the brain that people connect with their current surroundings and activities.

are claims about the effects of meditation most likely scientific or pseudoscientific?

not pseudoscientific, because people have made claims about it but scientific observations have not been made