Animal Cardiovascular and Respiratory Systems

These flashcards cover key concepts related to animal cardiovascular and respiratory systems, focusing on mechanisms of gas exchange and respiratory structures.

Diffusion

Random movement of molecules, resulting in net movement from regions of higher concentration to lower concentration.

Fick’s Law of Diffusion

States that the rate of diffusion is proportional to the concentration difference across a membrane and the surface area while inversely proportional to the membrane thickness.

Ventilation

The movement of an animal’s respiratory medium—water or air—past a specialized respiratory surface.

Countercurrent Exchange

A mechanism in which blood flows through capillaries in the opposite direction of water flow, optimizing pressure differential for gas exchange.

Tidal Ventilation

Breathing technique in terrestrial vertebrates where air is drawn into the lungs during inhalation and moved out during exhalation.

Alveoli

Small air sacs in mammalian lungs where gas exchange occurs, providing a large surface area.

Parabronchi

Tiny air vessels in bird lungs where gas exchange occurs with unidirectional airflow.

Hemolymph

The fluid that circulates in the open circulatory systems of invertebrates, functioning similarly to blood.

Lungs

Terrestrial respiratory organs that allow for gas exchange through a uniform air pool.

Diaphragm

A domed sheet of muscle located at the base of the lungs that separates the thoracic and abdominal cavities, playing a crucial role in respiration.