The Union of the Sperm and the Egg That Results

question 22

Multiple Choice

The union of the sperm and the egg that results in a cell with 46 chromosomes is called a(n) ________.

• A) embryo
• B) zygote
• C) fetus
• D) trophoblast

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Definitions:

Gamma Motor Neurons

Neurons that control the sensitivity of muscle spindle fibers to stretch, thereby adjusting the tension of muscles.

Muscle Spindles

Sensory receptors within muscles that detect changes in muscle length and participate in regulating muscle contraction.

Alpha Motor Neurons

Nerve cells that connect to and control the contraction of skeletal muscles, playing a key role in initiating muscle movement.

Reflex Arc

The neural pathway that controls a reflex action, typically comprising a sensory receptor, a neural pathway, and an effector.