Transport in Humans and Animals

The figure below shows the mechanism of blood clotting.When a blood vessel is damaged, platelets will gather around the wound and coagulate.At the same time, an enzyme called thrombokinase will be released.Thrombokinase will convert the inactive prothrombin to the active thrombin.The thrombin will then catalyses the soluble fibrinogen to the insoluble fibrin.Fibrin will form a … Read more

Hemostasis Hemostasis is a process which causes bleeding to stop and keep blood within a damaged blood vessel. It is the first stage of wound healing.Blood clotting is an important part of hemostasis, wherein a damaged blood vessel wall is covered by a platelet and fibrin-containing clot to stop bleeding and begin repair of the damaged … Read more

Pressure is how much force exerted on one unit area of a surface.Blood pressure is the pressure exerted by the blood on the walls of the blood vessels.Sometime, it is also called the arterial blood pressure as it is the pressure in the arteries.Normal Blood PressureWhen measuring blood pressure, we measure thesystolic pressure (highest pressure … Read more

The circulation of blood in human is due to the pumping of the heart.The cardiac muscles contract to produce heartbeat which pumps the blood to the whole body.The Cardiac Cycle( Image by Madhero88 shared under the Creative Commons Attribution 3.0 Unported license. )The heartbeat is initiated by the sinoatrial node (also called the SAN or pacemaker) … Read more

(Image by unknown author under Creative Commons Attribution-Share Alike 3.0 Unported license.)StructureThe human heart consist of four compartment:two upper chambers (left atrium and right atrium) two lower chambers (left ventricle and right ventricle)The chamber to the right is separated from the chamber to the left by a wall called septum.The Atria and VentriclesThe atria are smaller and have thinner … Read more

Three types of blood vesselsarteryveincapillaryArtery: Carries blood from the heart to other parts of the body.Vein: Carries blood from other parts of the body back to the heart.The arteries divides into smaller branches called arterioles.The veins receives blood from smaller branches called venules.Capillaries: Blood vessels connect the arterioles and venules.Around the capillaries are body cells.(Image derived from … Read more

The circulatory system in humans is made up of two main circulation:pulmonary circulation (between heart and lung)systemic circulation (between heart and other body parts)This is known as a double closed and complete circulatory system.Pulmonary CirculationPulmonary circulation is the part of the circulation of blood in human body which carries deoxygenated blood away from the heart, to the … Read more

Circulatory system can be classified into two types:closed circulatory systemopen circulatory systemClosed Circulatory SystemUsually found in large animals such as vertebrates.Medium of transport is bloodThe blood  flows continuously in blood vesselsExchange of gases, nutrients and waste products occurs between the blood in the capillary and the body cell.Open Circulatory SystemUsually found in smaller animals such as insects … Read more

Haemolymph is a fluid in the circulatory system of insects.As blood, haemolymph is the medium of transport that transport substances such as hormone and nutrient to the cells.For most insects, haemolymph is not used for oxygen transport because these animals respirate directly from their body surfaces to air.Unlike blood in human’s circulatory system,the haemolymph does not flow in closed blood … Read more

Blood is an important medium intransport of oxygen and carbon dioxideIn blood, oxygen combines with haemoglobin in the red blood cell to form oxyhaemoglobin.Oxygen is transported in the form of oxyhaemoglobin to the body cells which lack of oxygen.At the body cells, oxyhaemoglobin breaks down to release the oxygen to the body cells for cell respiration.Carbon … Read more