Extended Response Practice Questions Flashcards
What are the main components of the circulatory system?
The circulatory system is composed of a pump (the heart) and blood vessels that carry blood to the cells in the body.
What is the function of arteries?
Arteries carry deoxygenated blood away from the heart, under high pressure.
What structural features of arteries relate to their function?
Arteries have smooth muscle and elastic fibers in their walls, allowing them to stretch and recoil.
What are capillaries and their role in the circulatory system?
Capillaries are microscopic blood vessels that link arteries and veins, allowing for nutrient and waste exchange.
Describe the structure of capillaries.
Capillaries have walls that are one cell thick, facilitating diffusion and transport of substances.
What is the function of veins?
Veins carry blood towards the heart, transporting deoxygenated blood at low pressure.
How do veins differ from arteries in terms of structure?
Veins have less muscle and elastic fibers, larger lumens, and contain valves to prevent backflow.
How is oxygen transported in the blood?
3% is dissolved in plasma and 97% is transported as oxyhaemoglobin.
What percentage of carbon dioxide is transported as bicarbonate ions?
70% of carbon dioxide is carried in plasma as bicarbonate ions (HCO-3).
What is the primary function of lymphatic vessels?
Lymphatic vessels collect excess fluid from tissues and return it to the blood.
List the main functions of blood.
- Transport nutrients and oxygen
- Regulate body temperature and pH
- Protect against blood loss and pathogens
What is plasma and its role in blood?
Plasma is a mixture of water with dissolved substances that transports blood components.
What is the function of erythrocytes?
Erythrocytes transport oxygen from the lungs to the cells throughout the body.
What distinguishes leucocytes from erythrocytes?
Leucocytes are larger, contain a nucleus, and protect the body from infection.
How long do thrombocytes last in the bloodstream?
Thrombocytes last about 7 days.
What discovery did Dr. Karl Landsteiner make in 1901?
He discovered the ABO blood grouping system.
What are the four blood groups in the ABO system?
- Blood Group A: A antigens, B antibodies
- Blood Group B: B antigens, A antibodies
- Blood Group AB: A and B antigens, no antibodies
- Blood Group O: No antigens, A and B antibodies
What does it mean to be Rh positive?
Rh positive individuals have Rh antigens and cannot produce anti-Rh antibodies.
What blood types can a person with blood group B receive?
They can receive blood types B and O.
What happens during a transfusion of incompatible blood types?
A person’s antibodies react with the donor blood’s antigens, causing agglutination.
What is the pulmonary circuit?
It carries deoxygenated blood from the heart to the lungs.
What is the systemic circuit?
It carries oxygenated blood from the heart to the rest of the body.
What is the main function of the lymphatic system?
To collect escaped fluid from blood capillaries and return it to the circulatory system.
What role do lymph nodes play in the immune response?
Lymph nodes filter lymph and trap foreign particles and pathogens.
How do macrophages contribute to the immune response?
Macrophages destroy and ingest large particles like bacteria through phagocytosis.
What is the need for ventilation in humans?
To increase surface area for gas exchange due to a small surface area to volume ratio.
Define ventilation.
The process by which air is moved into and out of the lungs.
What is the difference between ventilation and gas exchange?
Ventilation is the movement of air; gas exchange is the diffusion of oxygen and carbon dioxide.
What causes emphysema?
Long-term exposure to irritating particles in the air, leading to lung damage.
What is lung cancer linked to?
Controlled division of cells, primarily caused by tobacco smoking and exposure to pollutants.
