Cardiovascular system Flashcards
What are the three main functions of blood?
Transportation
Regulation
Protection
What is the role of transportation with blood?
Blood carries essential substances throughout the body. Eg:
Oxygen from lungs to cells
Nutrients from the digestive system to cells
Hormones from glands to target organs
Waste products to be eliminated by organs like the kidneys
What is the role of regulation in the blood?
Blood helps maintain homeostasis by regulating body temperature, pH levels, and the water balance within the body.
What is the role of protection in the blood?
Platelets in the blood help in blood clotting to prevent excessive bleeding when theres an injury.
White blood cells within the blood are a part of the immune system and help fight infections, and diseases.
Functions of the CV system (Transportation)
Respiratory: transports O2 and Co2
Nutritive: Carries absorbed digested products to the liver and to the tissues
Excretory: Carries metabolic wastes to the kidneys to be excreted
Pulmonary circulation
Where the right side of the heart receives deoxygenated blood from the body and pumps it to the lungs for oxygen
Systemic circulation
The left side of the heart receives oxygenated blood from the lungs and pumps it to the rest of the body
Describe a simple CV drawing
Deoxygenated blood leaves the right ventricle, via the pulmonary artery and goes to the lungs where its oxygenated
It then travels via the pulmonary vein to the left atrium, goes down into the left ventricle via a valve, and then gets distributed to the body via the ascending aorta.
From the body, the oxygen gets used and the blood becomes deoxygenated, it then travels via the vena cava (superior and inferior) to the right atrium
The blood then moves down through the valve into the right ventricle, and begins the process again.
Functions of the CV system (regulation)
Hormonal: carries hormones to target tissues to produce effects
Temperature: Diverts blood to cool or warm the body
Protection: Blood clotting
Immune: Leukocytes, cytokines, and complement system acts against pathogens
What are the 3 components of the CV system?
The heart - The pumping action creates pressure needed to push the blood through blood vessels
Blood vessels - Permits blood flow from the heart to the cells, and back to the heart. Arteries, arterioles, capillaries, venules and veins
The lymphatic system - Transports interstitial fluid via lymphatic vessels. Lymph nodes filter and cleans lymph before it returns into venous blood.
Hepatic portal circulation
This is blood supply to and from the liver.
Blood from digestive organs (Gi tract, spleen, stomach, pancreas, gall bladder) passes through the liver via the hepatic portal circulation before going to the heart - this is different from the rest of the body as all other blood goes to the heart)
The liver receives blood from two major vessels - the hepatic portal vein and the hepatic artery.
After it passes through the liver it drains into hepatic veins, and then into the inferior vena cava.
This is important as blood from the digestive organs contains a lot of nutrients, the liver stores or modifies these to maintain correct nutrient concentrations. The blood may also have harmful substances in from the digestive system which the liver will detoxify so the substances aren’t passed to the rest of the body.
What % of the blood is made up of plasma?
55%
What % of the blood is made up of red blood cells?
41%
What % of the blood is made up of white blood cells?
4%
Lymphocytes, Basophils, Eosinophils, Monocytes and neutrophils
What % of the blood plasma is made up of water?
90-92%
