The Unpaired Air Sac in Birds Is the

question 70

Multiple Choice

The unpaired air sac in birds is the

• A) caudal thoracic air sac.
• B) cervical air sac.
• C) cranial thoracic air sac.
• D) interclavicular air sac.

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Definitions:

Presynaptic Terminal

The end point of a neuron where it connects to another neuron or muscle cell, releasing neurotransmitters to transmit nerve impulses.

Acetylcholine

A neurotransmitter involved in muscle activation and various functions in the central and peripheral nervous system, including memory and arousal.

ATP Molecule

Adenosine triphosphate, the primary carrier of energy in cells, facilitating energy transfer by undergoing enzymatic hydrolysis.

Cross-Bridge

The link formed between the actin and myosin filaments in a muscle fiber that generates contraction by shortening the muscle.