[Campbell Biology P.1033] Which statement accurately describes one of the key steps in the ve... | Practice Question

Which statement accurately describes one of the key steps in the vertebrate excretory system, as depicted in Figure 44.8?

  • A: Filtration: The process where valuable substances are reclaimed from the filtrate.
  • B: Reabsorption: Nonessential solutes and wastes are actively added to the filtrate.
  • C: Secretion: The altered filtrate (urine) is released from the system.
  • D: Excretion: Water and solutes are forced by blood pressure into the excretory tubule to form filtrate.
  • E: Reabsorption: Useful molecules and water are recovered from the filtrate and returned to body fluids.

Explanation

Figure 44.8 and the accompanying text define reabsorption as the process where the transport epithelium reclaims valuable substances from the filtrate and returns them to the body fluids. Filtration is the initial process of forming filtrate. Secretion is the active addition of nonessential substances to the filtrate. Excretion is the final release of urine.