The Circulatory System Flashcards
Four blood components?
-Plasma
-Platelets
-Erythrocytes
-Leukocytes
Function of plasma?
Transports waste, nutrients, hormones and water around the body
Function of platelets?
Form clots to stop bleeding and prevent pathogens from entering
Where are erythrocytes and leukocytes produced?
In the bone marrow
Function of erythrocytes?
-Contain haemoglobin to carry oxygen
Structure of erythrocytes?
-No nucleus so they can contain more haemoglobin
-Small and flexible to fit through narrow blood vessels
-Biconcave shape to maximise surface area for oxygen absorption
Three types of leukocytes?
-T lymphocytes
-B lymphocytes
-Phagocytes
Function of T-Lymphocytes?
Destroy pathogens and abnormal cells
Function of B-Lymphocytes?
Make antibodies which attach to bacteria and viruses
Function of Phagocytes
Ingest and destroy pathogens such as bacteria
What is the difference between single and double circulation?
Single circulation: blood only does one loop from heart to lungs to body.
Double circulation: blood goes through the heart twice, heart to lungs to heart to body
Function of arteries?
Carry oxygenated blood away from the heart and deliver it to cells around the body
*Exception: pulmonary artery (carries deoxygenated blood from heart to the lungs)
Structure of arteries?
-Under high pressure
-Smaller lumen
-Thick outer walls
Function of veins?
Carry deoxygenated blood from the body to the heart
*Exception: pulmonary vein (carries oxygenated blood from lungs to the heart)
Structure of veins?
-Under low pressure
-Have valves to prevent back flow
-Larger lumen
-Thinner outer walls