6) The human heart is a/n a. cell b. organism _ c. organ

7) The group of organs that work together is called
a. organ system b. roots hair system C. sense organs

8) What is being produced when muscle contracts?
a. Movement b. New organ c. Nothing ​

organ

system

movement

Explanation:

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6) c 7) a 8)a

Explanation:

Heart is said to be organ under the level of complexity. Heart is a complex composition of tissues

Group of organ that works together is known as organ system

Movement in organisms bring about contraction and relaxing of muscles

the endocrine system secretes hormones into blood and other body fluids. these chemicals are important for metabolism, growth, water and mineral balance, and the response to stress. hormones provide feedback to the brain to affect neural processing. reproductive hormones affect the development of the nervous system.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.