Reproductive Systems with External Fertilization Are Most Common in

question 43

Multiple Choice

Reproductive systems with external fertilization are most common in

• A) terrestrial animals.
• B) populations with many more males than females.
• C) animals that are widely dispersed.
• D) aquatic animals.

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Definitions:

Sarcomeres

The basic contractile unit of muscle fiber, consisting of actin and myosin filaments between two Z-lines.

Myofilaments

Protein filaments consisting of actin and myosin that are the primary components of muscle contraction.

Acetylcholine

A neurotransmitter in both the central and peripheral nervous systems that plays key roles in arousal, attention, memory, and muscle activation.

Neuromuscular Junction

A specialized synapse between a motor neuron and a muscle fiber, through which signals are transmitted to initiate muscle contraction.