Section 2h Transport Flashcards
Describe the composition of the blood: red blood cells, white blood cells, platelets and plasma.
Blood consists of many cells, such as: Red blood cells, white blood cells (lymphocytes and phagocytes), platelets and plasma.
Red blood cells - Transports oxyhaemoglobin throughout entire body
White blood cells:
-Lymphocytes - Creates antibodies that bind to antigens, killing the pathogen. They have complimentary shapes to antigens. Some lymphocytes may persist in the blood, giving us immunity to specific diseases.
-Phagocytes - Engulfs the bacteria in a vacuole and sends digestive enzymes to destroy the bacteria.
Platelets - Fragments of other cells, help clot blood when we cut ourselves.
Plasma - Mainly water. Carries heat, CO2, urea and other nutrients.
What is the role of plasma?
To transport nutrients, hormones and red blood cells throughout the body. Also carries CO2, food and distributes heat.
Explain how adaptations of red blood cells make them suitable for the transport of oxygen.
Shape - Their biconcave shape allows more oxygen to be exchanged in and out of the shell.
No nucleus - Means more haemoglobin can bind to the red blood cell so more oxygen can be transported.
Large surface area to volume ratio.
Very thin cell surface membranes.
How the heart works:
Deoxygenated blood enters the heart through the vena cava. It enters the right atrium, then through the tricuspid valve which closes after (to prevent the back flow of blood). The blood enters the right ventricle and is pushed through the semi lunar valve by the cardiac walls (increasing the pressure) and through the pulmonary vein.
Blood travels through the lungs where gas exchange between the alveoli and capillaries occur. Oxygen diffuses into the blood and Carbon dioxide diffuses into the alveoli.
The blood then flows back to the hear through the pulmonary vein and enters the left atrium. It goes through the bicuspid valve which closes after as well and enters the left ventricle. Cardiac walls once again contract, increasing the pressure and pushes the blood through another semi lunar valve which heads to the aorta. The aorta then takes the blood throughout the rest of the body to supply our organs with oxygen.
The cycle is repeated.
What is the general structure of the circulation system to include the blood vessels to and from the heart, the lungs, stomach, the liver and the kidneys.
Vein - To heart Artery - Away form heart Kidney - Renal Stomach - Gastric Liver - Hepatic Between stomach and liver - Heptic Portal Vein
Where is adrenaline found in the body and what does it do to do the heart?
Adrenaline - Released from the adrenaline glands. Increases the rate at which your heart cells work at. Makes the heart pump harder and faster.
Explain how the heart rate changes during exercise.
As you exercise, your muscles contract more and more and so your muscles need more energy from respiration. That means more oxygen needs to be brought to your cells for aerobic respiration. The heart needs to pump harder and faster in order to pump more blood containing oxyhemoglobin throughout your body so that the oxygen can diffuse into your cells for respiration.
Describe the structure of the arteries, veins and capillaries.
Arteries - Have a smaller lumen than the vein compared to it’s wall. Has thick and strong muscle layer to withstand pressure.
Veins - Have a larger lumen than the vein compared to it’s wall. Has valve to stop back flow.
Capillaries - One cell thick so they can allow nutrients like O2 and glucose to diffuse into cells and vice versa.
