If a One-Hour-Old Infant Sticks Out Her Tongue in Response

question 138

Multiple Choice

If a one-hour-old infant sticks out her tongue in response to an adult doing the same, what has occurred?

• A) The infant observed the adult and then decided to stick out her tongue.
• B) Learning has occurred.
• C) Deferred imitation has occurred.
• D) Given the age of the child, this is most likely an imitation reflex.

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Definitions:

Cyclic AMP

A second messenger important in many biological processes, involved in the activation of protein kinases and regulation of the effects of adrenaline and glucagon.

G Proteins

A family of proteins that act as molecular switches inside cells, involved in transmitting signals from stimuli outside the cell.

Upregulation

The process by which a cell increases the quantity of a cellular component, such as RNA or protein, in response to an external stimulus.

Receptors

Proteins on the surface or inside of cells that bind to specific molecules like hormones or neurotransmitters, triggering a cellular response.