Disorder Related to the Circulatory System
High Blood Pressure (Hypertension)
Hypertension is the term for blood pressure that is higher than normal (120/80). In this measurement 120 mm Hg (millimetres of mercury) is the systolic, or pumping pressure and 80 mm Hg is the diastolic, or resting, pressure. If repeated checks of blood pressure of an individual is 140/90 (140 over 90) or higher, it shows hypertension. High blood pressure leads to heart diseases and also affects vital organs like brain and kidney.
Coronary Artery Disease (CAD)
Coronary Artery Disease, often referred to as Atherosclerosis, affects the vessels that supply blood to the heart muscle. It is caused by deposits of calcium, fat, cholesterol and fibrous tissues, which makes the lumen of arteries narrower.
Angina
It is also called "Angina Pectoris". A symptom of acute chest pain appears when no enough oxygen is reaching the heart muscle. Angina can occur in men and women of any age but it is more common among the middle-aged and elderly. It occurs due to conditions that affect the blood flow.
Heart Failure
Heart failure means the state of heart when it is not pumping blood effectively enough to meet the needs of the body. It is sometimes called congestive heart failure because congestion of the lungs is one of the main symptoms of this disease. Heart failure is not the same as cardiac arrest (when the heart stops beating) or a heart attack (when the heart muscle is suddenly damaged by an inadequate blood supply).
1.0Portal System
When the vein of any organ of the body does not open in the caval vein or heart but it divides into capillaries in any other organ and its blood is transported by vein of that other organ to the heart, then this type of system is termed as Portal System. Types of Portal System are
Renal Portal System
Veins which collect blood from posterior parts of the body and legs combine to form a renal portal vein. This vein goes into kidney and divides into capillaries, kidneys separate nitrogenous wastes from this blood.
In mammals, renal portal system is absent.
In Frog both the portal systems; renal portal system and hepatic portal system are present.
Hepatic Portal System
It is a portal system which brings venous blood directly from digestive tract, spleen, pancreas and gall bladder to liver for extraction of nutrients and other metabolites by breaking up into single celled thick capillaries.
Hypophyseal Portal System
It is a portal system formed by a vein from hypothalamus which breaks up into capillaries in anterior lobe of pituitary gland (Adenohypophysis). The vein is called hypophyseal portal vein. Hypothalamus produces a number of hormones for controlling endocrine activity of adenohypophysis.
2.0Lymphatic System
Lymphatic system consists of lymphatic capillaries, lymphatic vessels, lymph nodes and lymphatic organs (spleen and thymus).
Lymph flows in one direction only i.e. from tissues to heart.
Capillaries have very fine pores through which blood plasma filters out and starts flowing into the intercellular spaces. This fluid is called as extracellular/tissue/interstitial fluid. A part of this fluid enters into the lymph capillaries. The fluid inside the lymph capillaries is called lymph.
Lymph is clear, transparent fluid which contains blood plasma, WBC and some proteins.
Lymph enters into lymph capillaries which join together to form large lymph vessels. The lymph vessels finally drain lymph into large veins.
The lymphatic nodes occur at intervals in the course of the lymphatic vessels. It contains lymphocytes, plasma cells and macrophages. The lymph filters through the lymphatic nodes. The macrophages remove microorganisms, cellular debris and foreign particles.
Functions of Lymph
(i) Lymphatic vessels drain excess interstitial fluid from tissue spaces & return it to the blood.
(ii) Lymphatic vessels transport lipid soluble vitamins absorbed by the gastrointestinal tract
(iii) In intestine, lymph help in absorption of fat through special lymphatic capillaries called lacteals.
(iv) Lymph has lymphocytes. It is therefore responsible for immune responses of the body.
3.0Also Read