Cardiology

Mammals and birds have which circuits

Systemic and pulmonary circuits which are divided which allows pressure to be different in both.

How many chambers in mammal and bird hearts

4 chamber, 2 atria and 2 ventricles. Oxygenated and deoxygenated blood separate.

Water breathing fish circuit

Low pressure, 4 chambers in series, atrium not muscular, contraction of single ventricle pumps blood to gills, no mixing of oxygenated and deoxygenated

Air breathing fish circuit

Tropical fish in low oxygen waters, 4 chambers in partially divided series, Evolved several times, ABO has increased capillary supply and is arranged parallel with systemic circulation. O and D blood mix

Lung fish circulation

Partially divides, limited mixing of D and O blood, 2 atria in heart separate the 2 blood streams in ventricle by septum, Common ancestor to tetrapod

Larval Lamprey circulation

Heart has mixture of oxygen rich and oxygen depleted blood

Gill breathing fish

Heart contains only oxygen poor blood

Primitive air breathing fish

Mixture of oxygen rich and oxygen depleted blood

African lungfish

Almost complete separation of oxygen rich and oxygen depleted blood

Amphibian Circulation

Heart is partially divided with 2 atria and 1 ventricle, deoxygenated blood can mix, blood streams are 80% separate, additional vessel from pulmonary vein to skin circulation

What is the function of trabeculae in amphibian heart

Within the ventricle has a spiral fold to keep oxygenated and deoxygenated blood separate

Where is trabeculae located

Conus arteriosus

Non-crocodilian reptile circulation

partially divided circulation, 2 outflow arteries from 1 ventricle, non mixing of oxygenated and deoxygenate blood

what are the 3 interconnected chambers in non-crocodilian reptile ventricles and what is it called.

Muscular septa that has cavum polmonale, cavum venosum and cavum arteriosum.

Function of Atrioventricular valve

Blocks blood flow by changing position. Creates temporary chambers.

Explain step one of cardiac contraction in turtles

1. Atria contracts 2. Left atrium pumps oxygenated blood into C arteriosum 3. Right atrium pumps deoxygenated blood through C.Venosum across septum into C. pulmonale 4. AVV blocks intraventricular canal

Explain step 2 of cardiac contraction in turtles

1. Ventricle contracts 2. Deoxygenated blood in C. pulnonale is expelled via pulmonary arteries to lungs

2. AVV closes

3. Oxygenated blood in C. arteriosum forced into C. venosum and expelled through RAA, LAA to systemic circulation

4. Mixing of blood is prevented by squeezing tg of the muscular ridge and ventricle wall

Crocodile Circulation

Divided heart and circulation, 2 atria and 2 ventricle, vessels constrict in pulmonary system, pressure in R ventricle increases to be greater than L.

How do crocodiles promote blood flow to the body when swimming

Right ventricular valve ope4ns, Deoxygenated blood flows from L aorta through foramen of panizza into R aorta which increases blood flow to the limbs. (closes blood flow to the lungs).