11. Blood Flashcards
How does exchange with the envionrment occur in mammals
The circulatory system - it acts as a link to transport nutrients and oxygen to cells and waste products away
What are five functions of blood? Think about the way blood flows through your bod and what bodily functions must occur
- Respiratory and gas exchange
- Regulation of hormones, PH and body temperature
- Distribution of nutrients
- Excretion of metabolic products
- Carrier of immunological protective agents
What is the composition of blood (%)? Including the volume of celluar elements in humans, the type of tissue and one more point (where blood is within)
Celluar elements occupies about 45% of the volume of blood
Blood is a type of connective tissue
Blood is within a matrix called the plasma
What is the composition of blood plasma and what solutes does it contain?
Blood plasma is about 90% water and contains electrolytes
What is the function of having water in blood plasma?
Its a solvent for carrying other substances
What is the function of have blood electrolytes? Three points
- osmotic balance
- pH buffering (keeping pH constant)
- regulation of membrane permeability
Name three plasma proteins and what each of their functions are
Albumin - osmotic balance, pH buffering
Fibrinogen - clotting
Immunoglobulin (antibodies) - for defence
What are the three celluar elements in the plasma and what is each of their function? In order of highest number in blood to lowest
Red blood cells - transport oxygen
White blood cells - immune function
Platelets - found in bone marrow, required for blood clotting
What is the structure and the function of a red blood cell? (Erythrocytes)
The structure is they have biconcave discs which is like a dent in the cell.
This helps with the function of a large surface area:volume ratio to enhance gas exchange as RBC can bind easier to oxygen and is flexible to transport the oxygen around the body.
What is the structure of a capillary where red blood cells flow through and how does this relate to function of absorption, excretion and secretion
Capillaries are made of endothelial cells (epithelial cells that line capillaries) which have tight junctions in them.
the tight junctions allow fluids to leak out to make the ICF fluid.
The clefts and pores allow water solvable solutes to pass through
Lipid soluble molecules can diffuse through endothelial membrane
What are the five main types of white blood cells?
Neutrophils
Eosinophils
Basophils
Monocytes
Lymphocytes
What are innate immunity white blood cells? What four white blood cells does it include?
They are present before exposure to pathogens and from the time of birth. NONSPECIFIC response to pathogens
Monocyes, neutrophils, eosinophils and basophils
What the most common innate WBC and how does its structure relate to its function in the immune system?
Its a neutrophil! Its structure has the ability to move, which means its function is that that it detects substances (eg infections) and moves towards it to attack
How do neutrophils move to reach the site of infection? What is this process called?
The neutrophil rolls along a layer of endothelial cells inside a blood vessel unit lit finds a gap, then it squeezes through to the site of infection. Process called diapedesis
What do monocytes and neutrophils have in common? 3 points
They can be found moving through the body
Found in organs of the lymphatic system (network of tissues and organs to get rid of toxins)
Phagocytic white blood cells (eat unwanted cells and matter)
What type on innate WBC is a ‘natural killer cell’ and what is its function?
Its a type of lymphocyte. It patrols the body and attracts viruses and kills them
What are the two types of ‘adaptive immunity lymphocytes’? Where are they each matured and what are two functions of each?
B lymphocytes
- matures in bone marrow
- generates antibodies
- produces memory and plasma cells
T lymphocytes
- mature in the thymus
- three subsets: Cytotoxin T cells, Helper T cells and Suppressor T cells - cytotoxic T cells kills cells that have become infected
What type of stem cell regenerates the population of of red blood cells?
Haematopoietic stem cell (HSC)
What is the lifespan of a red blood cell and where are new ones generated?
About 120 days, generated in bone marrow
How does blood clot when you get cut? Three steps
- The endothelium is damaged exposing the blood and connective tissue
- The platelets form a plug by releasing a chemical to make them sticky
- Seal is reinforced by a cascade of 4 hormones - prothrombin –> thrombin –> fibrinogen –> fibrin (which is insoluble so it clots)
