Circulatory Systems, Blood, & Blood Vessels

Flashcards covering key terms and definitions related to the circulatory system, blood, and blood vessels.

Open circulatory system

A type of circulatory system where the circulatory fluid (hemolymph) bathes the organs directly and nutrients and wastes are exchanged between the hemolymph and body cells.

Closed circulatory system

A type of circulatory system where the circulatory fluid (blood) is confined to vessels and is distinct from interstitial fluid.

Single circulation

A system found in bony fish, rays, and sharks with a two-chambered heart where blood passes through the heart once per circuit.

Double circulation

A system found in crocodiles, birds, and mammals with a four-chambered heart where blood is pumped separately to the lungs and the rest of the body.

Capillaries

Smallest and narrowest blood vessels where gas, nutrient, and waste exchange occurs.

Arteries

Blood vessels that carry blood away from the heart.

Veins

Blood vessels that return blood to the heart.

Plasma

The liquid component of blood that makes up about 55% of blood volume, containing water, plasma proteins, and other substances.

Erythrocytes

Also known as Red Blood Cells (RBC), the most numerous blood cells that contain hemoglobin for oxygen transport.

Leukocytes

White blood cells (WBC) that are important for the immune response.

Platelets (thrombocytes)

Cell fragments that play a critical role in blood clot formation.