Recall That the Citric Acid Cycle Starts with a Four-Carbon

question 1

Multiple Choice

Recall that the citric acid cycle starts with a four-carbon molecule, but that most of its intermediates are molecules that contain six carbons. How is this possible?

• A)through the reaction of succinate and succinyl-CoA
• B)through the reaction of malate and oxaloacetate
• C)through the reaction of acetyl-CoA and oxaloacetate
• D)through the reaction of malate and fumarate
• E)through the reaction of citrate and cis-aconitate

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Definitions:

Fovea Centralis

A small depression in the retina of the eye where visual acuity is highest, responsible for sharp central vision.

Interoceptors

Sensory receptors located within the body that detect internal stimuli, such as changes in blood pressure or muscle tension.

Chemoreceptors

Sensory receptors that respond to chemical stimuli, such as changes in the concentration of chemicals in the environment, and help organisms respond to taste and smell.

Photoreceptors

These are specialized cells in organisms that respond to light, allowing for the perception of vision and light-related responses.