1.1 Composition of blood Flashcards
What is the function of plasma?
It makes up 55% of the overall composition of blood. 90% of it is made up of water so it is very good for transportation as other molecules can dissolve in it.
What molecules does plasma carry?
Many different molecules including electrolytes, proteins, hormones, glucose, urea, vitamins, and minerals.
What is the function of leucocytes (white blood cells)?
Responsible for identifying and fighting off infection.
What are the 3 most common types of leucocytes?
Neutrophils, Monocytes, and Lymphocytes.
What are the roles of these leucocytes?
Neutrophils are the first responders to infection. They recognise and engulf invading bacteria. This is called phagocytosis. Monocytes fight off bacteria, viruses and fungi. They also clear up dead cells from the blood stream. Lymphocytes produce antibodies, fight viruses, and destroy cancerous cells by producing B and T cells.
Do leucocytes contain a nucleus?
They contain a nucleus.
What is the function of erythrocytes (red blood cells)?
They are filled with haemoglobin which is used to transport oxygen and carbon dioxide from the lungs to all other tissues within the body.
What is the structure of erythrocytes?
They are biconcave in shape, meaning they have a large surface area so gases can move in and out of the cell. They have no nucleus leaving room for more haemoglobin and are flexible so they can move around narrow capillaries to deliver oxygen to other tissues.
Why are platelets not ‘true cells’?
Because they do not have a nucleus, they are cell fragments that travel repair damaged blood vessels.
What is the function of platelets?
Work with fibrinogen to heal damaged vessels. They travel to the damaged area and reacted with collagen in the torn vessel wall and becomes sticky, gluing up the damage. Fibrinogen then acts as a mesh and pulls the wound together, forming a clot.
