The functional unit of the kidney is called the:

Correct Answer: B

Rationale: The nephron (filtration to urine formation) is the kidney's functional unit not glomerulus (filtration site), ureter (transport), or Bowman's capsule (nephron part). This identifies the kidney's workhorse, critical for physiology, contrasting with its parts.

Correct Answer: A

Rationale: UTIs are bacterial (E. coli common) not viral, fungal (rare), or dietary. This identifies primary cause, key for treatment, contrasting with less common etiologies.

Correct Answer: A

Rationale: Aldosterone retains Na+, raising BP not insulin (glucose), thyroxine (metabolism), or oxytocin (labor). This specifies RAAS role, key for volume control, contrasting with unrelated hormones.

Correct Answer: D

Rationale: Podocytes have secondary processes (pedicels) contacting the basal lamina, form the visceral layer, and contain actin microfilaments all true. This comprehensively describes podocytes, key for filtration slits, contrasting with partial descriptions.

Correct Answer: D

Rationale: DCT responds to aldosterone (Na+/K+), ANF (Na+ excretion), and ADH (water) all apply. This encompasses hormonal regulation, key for electrolyte/water balance, contrasting with single or no control.