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Alina [70]
3 years ago
7

Alveoli are sac-like structures that serve as the site of gas exchange. a. True b. False

Biology
1 answer:
RUDIKE [14]3 years ago
8 0

Answer:

True.

Explanation:

Alveoli are the microscopic structure present deep inside the lungs. Alveoli acts as a basic unit of ventilation. Alveoli are present in the lungs of mammals only.

Alveoli are hollow sac like structures when viewed under the microscope. Alveoli are the main site of the gas exchanges in the mammals. The alveoli are covered by the epithelial layers.

Thus, the correct answer is option (a).

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5 0
3 years ago
There are the same amount of carbon atoms on Earth now as there were in the past, but there are more in the atmosphere ever befo
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Answer:

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Explanation:

Hint the root word is in the option and it is actually shaped like a column according to Epithelium - Wikipedia

Hope this helps : )

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Answer:

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Explanation:

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3 years ago
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