Question

the hair on jamals arms is standing straight up.
what most likely explains why his hair is behaving this way?
he is in a cold area.
he is sweating.
he is in danger of bacteria.
he is receiving information for touch.

Explanation:

Analyze the physiological response

The prompt describes a situation where the hair on Jamal's arms is standing straight up. This physiological phenomenon is known as piloerection (commonly referred to as "goosebumps").

Identify the purpose of piloerection

Piloerection is a reflex response controlled by the sympathetic nervous system. Tiny muscles at the base of each hair follicle, called arrector pili muscles, contract and pull the hair upright.

Evaluate the given options

• He is in a cold area: When the body is exposed to cold, piloerection helps trap a layer of air close to the skin, acting as insulation to retain body heat. This is a key mechanism of thermoregulation.
• He is sweating: Sweating is a cooling mechanism where sweat glands release moisture to evaporate from the skin. It does not cause hair to stand up.
• He is in danger of bacteria: The immune response to bacteria involves white blood cells and antibodies, not piloerection.
• He is receiving information for touch: While hair follicles have sensory receptors, hair standing straight up is a motor response (muscle contraction) rather than a sensory input mechanism.

Determine the most likely explanation

The most likely explanation for Jamal's arm hair standing straight up is that his body is responding to a cold environment to conserve heat.

Answer:

• (A) He is in a cold area. (Correct answer)
• (B) He is sweating.
• (C) He is in danger of bacteria.
• (D) He is receiving information for touch.