Farah Hani binti Munjiat

116640

BZT214

CIRCULATORY SYSTEM

FISH HEART

REPTILE (NON-CROCODILIAN) HEART

MAMMAL HEART

Circulatory system of

fish

Circulatory system of reptile Circulatory system of mammal

Differences of The

Vertebrates Heart Structure

FISH REPTILE HUMAN

Efficiency Simplest/ earliest

design- not an

efficient system

More efficient than

fish

Maximum

efficiency

Chambered heart Four Five Four

Circulatory system Single Double Double

Type of myocardium Spongy Almost entirely

spongy

Compact

Blood enters through Sinus venosus Pulmonary veins Pulmonary veins

and vena cava

Location of

pacemaker cells

Sinus venosus Sinoatrial node Sinoatrial node

Atria 1 2 2

Mixed oxygenated and

deoxygenated blood

Not mixed Mixed Not mixed

Ventricle 1 3 2

Shunt Absent Present (R-L and

L-R Shunt )

Absent

Septum Absent Partial septum Complete septum

Composed of cardiac muscle and connective tissue.

Complex walls with four main parts:

pericardium, epicardium, myocardium and endocardium.

Closed circulatory systems (except agnathans).

Myogenic – cardiomyocytes produce spontaneous rhythmic

depolarization.

heartbeat consists of a rhythmical contraction (systole) of the

cardiac muscle followed by relaxation (diastole).

Valves prevent backflow of blood.

SIMILARITIES OF HEART STRUCTURE

BETWEEN FISH, REPTILE AND HUMAN

Red blood cells (Erythrocyte)

Storage and transport of oxygen and carbon dioxide.

Deliver oxygen to the tissues and return carbon

dioxide from the tissues to the lungs.

Transport of gases is done by chemically complex

protein called hemoglobin.

FUNCTIONS OF THE BLOOD CELLS

(HEMATOCYTE)

Leukocyte

morphology

Functions in immunity

Neutrophil Uses phagocytosis to engulf damaged cells, microorganisms, and

other foreign particles.

Eusinophil Deliver cytotoxic chemicals and enzymes that kills parasite.

Involved in allergic reaction.

Basophil Leave circulatory system to accumulate at infected area.

Release cytotoxic chemicals that kills foreign particles.

Involved in inflammation.

Release paracrine factors; histamins and prostaglandins

Monocyte Monocyte mature into phagocytic macrophages.

Engulf and destroy any foreign particles and dead or dying cells.

Jawed vertebrates- Adaptive immunity

Lymphocyte B cells secrete antibodies.

Helper T cells secrete molecules that activate other lymphocyte.

Killer T cells (cytotoxic T cells) secrete cytotoxic chemicals that kill

any invaders or dying cells.

• WHITE BLOOD CELLS

- FUNCTIONS IN IMMUNE RESPONSE

Essential in blood clotting.

Involve three steps

When blood vessel damaged, sympathetic nervous system

activated.

Induce vessel to vasoconstrict, reducing blood flow

Platelet plug formed, temporarily seals he opening. Fibrin

clot stabilizes the plug.

Clot forms to series of steps terms coagulation cascade.

This process can happen both inside the body; help stop

internal bleeding, and outside the body; help stop bleeding

from a cut.

THROMBOCYTES