Biology Anatomy and Physiology Flashcards

Which part of the nephron is responsible for the selective reabsorption of most filtered glucose and amino acids?

Answer: Proximal convoluted tubule

The proximal convoluted tubule reabsorbs approximately 65% of filtered water, nearly all glucose, and most amino acids via active transport.

The hormone calcitonin, which lowers blood calcium levels, is secreted by which gland?

Answer: Thyroid gland

Calcitonin is produced by parafollicular (C) cells of the thyroid gland and inhibits osteoclast activity to reduce blood calcium.

Which type of cartilage forms the intervertebral discs and the pubic symphysis?

Answer: Fibrocartilage

Fibrocartilage is the toughest cartilage type, with abundant collagen fibers that resist compression and tension in weight-bearing joints.

During which phase of the cardiac cycle does the ventricle fill with blood?

Answer: Ventricular diastole

Ventricular diastole is the relaxation phase during which AV valves open and blood flows from the atria into the ventricles.

Which cranial nerve is responsible for controlling most of the extrinsic eye muscles?

Answer: Oculomotor nerve (CN III)

The oculomotor nerve (CN III) innervates four of the six extrinsic eye muscles, as well as the levator palpebrae and pupillary constrictor.

What is the name of the connective tissue sheath that surrounds an entire skeletal muscle?

Answer: Epimysium

The epimysium is the dense irregular connective tissue layer that wraps the entire muscle and merges with tendons at the muscle's ends.

Which plasma protein is most important for maintaining blood osmotic pressure?

Answer: Albumin

Albumin, the most abundant plasma protein, is the primary contributor to colloid osmotic pressure, keeping fluid within blood vessels.