Elasmo Chapter 7 (Circulation, Respiration, Metabolism)

Arteries

High-pressure distributive system

Capillaries

Exchange system

Veins

Low-pressure reservoir

Single circuit flow

Heart → Gills → Body → Back to heart

Coronary Circulation

Supplies myocardium with oxygen and blood, first evolved in Chondrichthyans

Myocardium

Heart muscle/tissue

Systemic Circulation

Distributes oxygenated blood from the dorsal aorta to the head and trunk

Dorsal circulation

Oxygenated blood returns to the gills and is distributed to the rest of the shark

Ventral circulation

Deoxygenated blood flows from the heart to the gills

Anterior Cardinal Sinus

Drains the head

Posterior Cardinal Sinus

Drains the posterior body and kidneys

Hepatic Sinus

Drains the liver and acts as a blood reservoir

Erythrocytes

Nucleated red blood cells (gas exchange)

Leukocytes

White blood cells

Epigonal Organ

Organ stored in the gonad, produces stem cells

Leydig’s Organ

Found in the esophagus wall, produces red blood cells

Sinus venosus → Atrium → Ventricle → Conus arteriosus

Chamber order in shark hearts

Sinus venosus

Receives venous blood

Atrium

Collects blood and transfers it to ventricle

Conus arteriosus

Maintains pressure and smooths flow to gills

Pericardium

Semi-rigid sac surrounding the heart

Pericardio Peritoneal Canal (PPC)

Equalizes pressure between the pericardial and abdominal cavities

Shark Cardiac Output formula

Stroke volume x Heart rate

Stroke Volume

Amount of blood pumped per heartbeat