Which of the Following Did Early Methanogens Use from the Early

question 43

Multiple Choice

Which of the following did early methanogens use from the early atmosphere to generate energy?

• A) CO₂ and H₂
• B) H₂O and O₂
• C) CH₄ and CO₂
• D) N₂ and O₃
• E) O₂ and H₂

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Definitions:

Endocrine Gland

An endocrine gland is a gland that secretes hormones directly into the bloodstream to regulate various bodily functions.

Target Tissue

Specific tissues or cells in an organism that are affected by specific hormones or drugs.

Glucagon

A hormone produced by the pancreas that raises blood glucose levels by promoting the breakdown of glycogen to glucose in the liver.

Gluconeogenesis

A metabolic pathway that results in the generation of glucose from certain non-carbohydrate carbon substrates such as lactate, glycerol, and glucogenic amino acids.