Why Has the Development of an HIV Vaccine Been Very

question 92

Multiple Choice

Why has the development of an HIV vaccine been very difficult?

• A)because the virus produces enzymes that destroy the vaccine
• B)because the virus is a DNA virus, and vaccines work against only RNA viruses
• C)because the virus has no antigens to target
• D)because the viral coat antigens change frequently as the virus replicates

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Definitions:

Sensorimotor Development

The stage in early childhood development in which an infant's understanding of the world is based on their sensory experiences and motor actions.

Motor Skills

Abilities required to perform movements and tasks, involving the coordination of muscles and the nervous system, categorized into fine (small movements) and gross (larger movements) motor skills.

Gross Motor Skills

Abilities required to control the large muscles of the body for walking, running, sitting, and other activities.

Human Survival

The ability of humans to continue living or existing, often despite challenging conditions or threats.