Choose the Correct Answer from the List Below

question 24

Multiple Choice

Choose the correct answer from the list below. Not all of the answers will be used.
-____________: An amino acid that must be supplied by the diet.

• A)L amino acids
• B)water
• C)protons
• D)zwitterions
• E)leucine
• F)serine
• G)tyrosine
• H)cysteine
• I)glutamate
• J)histidine
• K)proline
• L)asparagine
• M)D amino acids

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Definitions:

Lymphatic System

A subsystem of the cardiovascular system; returns excess interstitial fluid (lymph) to the circulation; defends the body against disease organisms.

Interstitial Fluid

The fluid that surrounds the cells in tissues and is exchanged with the blood, providing nutrients and removing waste materials.

Pacemaker

A device implanted in the chest to regulate the heartbeat.

Atrioventricular Node

A part of the cardiac conduction system that coordinates the top heart chambers (atria) contraction with the bottom chambers (ventricles) ensuring a synchronized heartbeat.