The answer should be the contraction of muscles.
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3 position of the molecules.
Most of the ways to stop invasive animal species from entering the Great Lakes ecosystem is starting with people themselves. try not to plant anything that would be invasive to the echo system and also try helping out by cleaning out the Great Lakes by picking up litter and so forth
Answer:
OSHA's Hazard Communication standard, also known as the “Right to Know Law,” is designed to ensure that vital information about chemical hazards and protective measures is passed along to workers who may come in contact with or handle these types of chemicals.
Explanation:
The blood vessels farthest from the heart must have valves.
The valves which are present in the blood vessels prevent the backflow of the blood back into the specific organ.
There are different valves present in the heart are:
- The tricuspid valve is situated between the right atrium and right ventricle.
- The pulmonary valve is between the right ventricle and the pulmonary artery.
- The mitral valve is between the left atrium and left ventricle.
- The aortic valve is between the left ventricle and the aorta.
Other vales which are present in the blood vessels are in leg. Leg veins do require the valves. If not present the blood will go back down into the feet because of the gravity. Thus there are various valves present in the leg veins.
Valves in veins are bicuspid, meaning they have two flap-like structures that regulate blood flow in the vein.
To know more about the Valves, refer to this link:
brainly.com/question/12926213
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