How Many Chromosomes Does a Human Zygote Begin with at Conception

question 55

Multiple Choice

How many chromosomes does a human zygote begin with at conception?

• A)2
• B)23
• C)46
• D)8 million

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Definitions:

Receptor Molecules

Proteins located on the cell surface or within cells that bind specific substances, triggering a biological response.

Up-regulation

refers to the process of increasing the response to a stimulus, often involving an increase in the number of receptors on a cell's surface.

Receptor Sites

Specific locations on cell surfaces or within cells where molecules, such as hormones or neurotransmitters, bind to elicit a response.

Membrane-bound Receptor Model

A theory describing how specific proteins located on the cell membrane bind to external molecules, triggering a response inside the cell.