Excretory Systems in Biological Sciences II

These flashcards cover key concepts related to the excretory systems discussed in the lecture, including functions, terms, mechanisms, and adaptations relevant to osmoregulation and nitrogenous waste excretion.

What are the three main functions of excretory systems?

1. Solute concentration/Ionoregulation 2. Osmoregulation 3. Removal of nitrogenous wastes.

Define the term U/P osmotic pressure ratio.

The U/P osmotic pressure ratio is the ratio of urine and plasma osmotic pressures, reflecting kidney function.

What does it mean when the U/P ratio is less than 1.0?

The kidneys are making dilute urine, and the plasma is becoming more concentrated.

What is the primary nitrogenous waste product excreted by aquatic organisms?

Ammonia (NH3).

Name two groups of animals that utilize extrarenal salt excretion.

Sea birds and sea turtles.

How do freshwater animals cope with water gain?

Freshwater animals do not drink water and produce large amounts of urine to expel excess water.

What is a key adaptation of kangaroo rats to prevent water loss?

They live in deep, cool burrows during the day and produce extremely concentrated urine.

What are the two types of adaptations for coping with variable osmotic environments?

1. Osmotic conformers 2. Osmotic regulators.

What is the role of the Bowman’s capsule in the nephron?

It contains a cluster of capillaries (glomerulus) where blood filtration occurs.

What is the function of ADH in the nephron?

ADH creates concentrated urine by making the collecting duct permeable to water.