Figure 16.3 Above Is a Metabolic Pathway for the Synthesis of an of an Amino

question 24

Multiple Choice

Figure 16.3
Above is a metabolic pathway for the synthesis of an amino acid E) , without which an organism could not live. Enzymes are represented by numbers, and substrates by letters. Use this figure for the next questions.
-According to the figure above, if enzyme 3 was nonfunctional in an organism, which of the following outcomes would you predict?

• A) The cell would die because of a lack of the essential amino acid.
• B) Substrate C would accumulate, and there would be no substrate D formed.
• C) Lack of enzyme 3 would result in a cessation halt) of the entire metabolic pathway.
• D) Another enzyme would be able to catalyze the reaction and the pathway would proceed.

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Definitions:

Muscle

Tissues in the body that can contract, allowing movement of body parts and organs.

Notochord

The notochord is a flexible rod-like structure that forms the main axis of the embryo in all chordates, providing support and defining the primitive axis of the embryo.

Mesodermal Tissue

The middle layer of embryonic tissue that develops into muscle, bone, and the circulatory system among others.

Neural Plate

The neural plate is the flat layer of embryonic cells that develops into the neural tube, eventually forming the brain and spinal cord.