Biology Human Anatomy & Physiology Flashcards

Which cranial nerve is responsible for the majority of parasympathetic innervation of the thoracic and abdominal organs?

Answer: Vagus nerve (X)

The vagus nerve (CN X) provides parasympathetic innervation to the heart, lungs, and most abdominal organs.

Osteoblasts are responsible for which primary bone function?

Answer: Bone formation and matrix secretion

Osteoblasts synthesize and secrete the organic bone matrix (osteoid) and facilitate its mineralization.

Which blood vessel carries oxygenated blood from the lungs to the heart?

Answer: Pulmonary vein

The pulmonary veins are unique among veins in carrying oxygenated blood, returning it from the lungs to the left atrium.

The conversion of fibrinogen to fibrin during blood clotting is catalyzed by which enzyme?

Answer: Thrombin

Thrombin cleaves fibrinogen into fibrin monomers, which polymerize to form the stable clot mesh.

Which structure connects the hypothalamus to the posterior pituitary gland and transports hormones like ADH and oxytocin?

Answer: Axons of hypothalamic neurons

Axons of supraoptic and paraventricular hypothalamic neurons travel to the posterior pituitary to release ADH and oxytocin.

The functional unit of skeletal muscle contraction, bounded by two Z-lines, is called the:

Answer: Sarcomere

The sarcomere is the basic contractile unit of striated muscle, extending from one Z-line to the next.

Which lobe of the liver produces bile that is stored in the gallbladder?

Answer: All hepatocytes throughout the liver produce bile

Bile is continuously produced by hepatocytes throughout the entire liver and flows into bile canaliculi toward the gallbladder.