Complete information on the Circulatory System of Mammal

Circulatory system of mammal consists of the systems like:

A. Blood Vascular System

B. Lymphatic System,

A. Blood Vascular System:

In this system blood flows in blood vessels. This system has three parts.

i. Heart

ii. Blood Vessels

iii. Blood

i. Heart:

Heart of mammal is conical in structure, present in between two lungs inside the thoracic cavity. It is covered by an outer love covering called pericardium. The broad end of heart is called the base and the conical end is called the apex on heart. Mammalian heart is four chambered, having two auricles and two ventricles.

Auricle:

Two auricles are separated by inter-auricular septum and thus auricles are known as left and right auricle. Right auricles receive deoxygenated blood from superior and inferior van cava and from coronary veins. Left auricle receive oxygenated blood from two pairs of pulmonary veins from both the lungs.

Ventricle:

The ventricles are thick muscular chambers and are separated by inter-ventricular septum into left and right ventricle. Right ventricles receive deoxygenated blood from right auricle through tricuspid valve. From right ventricle arises the pulmonary trunk, which is bifurcated into right and left pulmonary artery. The deoxygenated bloods are received by the pulmonary from the right ventricle and carry these to respective lungs for oxygenation.

Left ventricle receive oxygenated blood from the left auricle. From left ventricle arise the aortic arch, that receive the oxygenated blood from the ventricle and supply to each and every parts of the body.

ii. Blood Vessels:

Blood vessels are two types: (a) Arteries, (b) Veins

Arterial System:

The arteries of arterial system carry blood from the heart and supply into different parts of the body. Arterial system has two large arteries are Pulmonary Aorta and Aortic arch.

Pulmonary Aorta:

Pulmonary aorta arises from the right ventricle and is divided in to two left and right pulmonary artery that supply blood to the lungs respectively.

Aortic Arch:

Aortic arch arises from the left ventricle. After curving to left, runs posteriorly as dorsal aorta. It has the following arteries.

Coronary Arteries: Supply oxygenated blood to cardiac cells of heart.

Innominate Artery: Arise from the aorta and divides in to as follows:

Common Carotid: It is divided in to two as external and internal carotid artery.

Internal Carotid: Supplies blood to the brain.

External Carotid: Supplies blood to head, tongue, salivary gland and jaw.

Left Subclavion: Originate independently. The origin of left and right subclavion is different and each has three main branches.

Vertebral artery: Suupplies blood to spinal cord and brain.

Brachial: Supplies blood to fore limbs.

Internal Mammary Artery: Supplies inner side of vertebral wall of the thorax.

The aorta then turns left and runs beneath the vertebral column and forms dorsal aorta. Its branches are as follows;

Inter Coastal Arteries: Supplies blood to ribs and inter coastal muscles.

Phrenic arteries: Supplies blood to the diaphragm.

Celiac artery: It is divided into the arteries like (a) hepatic artery supplying blood to liver and (b) iliac gastric artery supply blood to stomach and spleen.

Anterior mesenteric: It has many branches to supply blood to duodenum pancreas, small intestine, caecum and colon.

Renal Artery: Supply blood to kidney as left and right renal artery.

Gonadial Artery: A pair of gonadial arteries supplies blood to male and female reproductive system.

Posterior mesenteric Artery: Supply to rectum.

Lumbar Artery: Two lumbar arteries supply blood to body wall.

Lilac Arteries: Supplies blood to the pelvic region and hind limbs.

Caudal Artery: Supplies blood to tail region.

B. Venous System:

Veinous system can be studied under three headings.

Pulmonary veins: Two pairs of pulmonary veins constitute the pulmonary system and collect blood from the lungs and supply it to left auricle.

System of Vanacava: This system is constituted by the superior and inferior vanacava.

Superior vanacava: It is formed of the union of following veins;

External jugular vein: Collect blood from face and neck.

Internal jugular vein: Collect blood from brain and neck.

Subclavian vein: Collect blood from shoulder and fore limb.

Anterior inter coastal veins: Collects blood from anterior inter-coastal spaces.

Azygous cardinal vein: Formed by the union of small veins.

Inferior Vanacava: It is formed of the following veins.

Internal iliac: Collects blood from the back of thigh and pelvis.

External iliac: Receive blood from the legs, lower abdomen, urinary bladder etc.

Ilio lumbar vein: Collects from hind part of abdominal wall.

Spermatic or ovarian vein: Collects blood from male and female reproductive system.

Renal veins: A pair of renal veins collects from Kidney.

Hepatic vein: Collects blood from liver.

Phrenic Vein: Collects blood from diaphragm.

Hepatic portal system: Hepatic portal system brings blood from alimentary canal, pancreas and spleen.

Blood:

Blood is a liquid connective tissue having blood cells (R.B.C. and W.B.C.) and blood plasma. This help in transportation of O2, CO2, nutrients, hormones and other materials.

Lymphatic system: In this system lymph flows in lymph vessels.