Biomedical Science & Human Anatomy Flashcards

What is the name of the cell junction that prevents molecules from passing between epithelial cells?

Answer: Tight junction (zonula occludens)

Tight junctions (zonulae occludentes) seal adjacent epithelial cells together, creating a barrier that prevents paracellular movement of molecules.

Which branch of the aorta supplies oxygenated blood to the heart muscle itself?

Answer: Coronary arteries

The left and right coronary arteries arise from the ascending aorta just above the aortic valve and supply oxygenated blood to the myocardium.

Which structure in the inner ear is responsible for detecting linear acceleration and gravity?

Answer: Otolithic organs (utricle and saccule)

The utricle and saccule contain otoliths (calcium carbonate crystals) that shift in response to gravity and linear acceleration, stimulating hair cells.

Which neurotransmitter is released at the neuromuscular junction to trigger skeletal muscle contraction?

Answer: Acetylcholine

Acetylcholine is released from motor neuron terminals into the synaptic cleft and binds nicotinic receptors on the motor end plate to initiate muscle depolarization.

The inguinal canal in males transmits which structure?

Answer: Spermatic cord

In males, the inguinal canal transmits the spermatic cord (containing the ductus deferens, testicular vessels, and nerves) from the abdominal cavity to the scrotum.

Which type of bone cell is responsible for resorbing (breaking down) bone matrix?

Answer: Osteoclast

Osteoclasts are large multinucleated cells derived from monocyte precursors that secrete acids and enzymes to dissolve bone mineral and matrix during remodeling.

Which region of the brain is primarily responsible for coordinating voluntary motor movements and balance?

Answer: Cerebellum

The cerebellum fine-tunes motor commands, coordinates voluntary movements, and maintains balance and posture by comparing intended and actual movement.