The immune system Flashcards
What 3 things does blood help to regulate?
-pH
-body temperature
-water content of cells
How does the blood prevent against blood loss?
Through clotting and combats microbes and toxins through the action of certain phagocytic white blood cells or specialised plasma proteins
What actually is blood and what is its 3 general functions?
-a liquid connective tissue that consists of cells surrounded by extracellular matrix
-transportation, regulation, protection
Explain how the blood fulfils one of its functions, transportation
-blood transports oxygen from the lungs to cells throughout the body and carbon dioxide from the cells to the lungs
-it also carries nutrients from the gastrointestinal tract to body cells, heat and waste products away from cells, and hormones from the endocrine glands to other body cells
Explain how the blood fulfils one of its functions, regulation
-blood helps regulate the pH of bodily fluids
-heat absorbing coolant properties of the water in blood transport and its variable rate of flow through the skin help adjust body temperature
-blood osmotic pressure also influences the water content of cells
Explain how the blood fulfils one of its functions, protection
-blood clots become gel-like in response to an injury, which protects against its excessive loss from the cardiovascular system
-white blood cells protect against disease by carrying on phagocytosis and producing proteins called antibodies
-blood contains additional proteins called interferons and complement that also help protect against disease
What are the physical components of whole blood?
-a viscosity greater than that of water
-temperature of 38 degrees
-a pH range between 7.35 and 7.45
-blood constitutes about 8% of body weight in an adult, and consists of 55% plasma and 45% formed elements
What are the formed elements in blood?
-red blood cells (erythrocytes)
-white blood cells (leukocytes)
-platelets
What percentage of water, proteins and solutes (other than proteins) are contained in blood plasma?
-91.5% water
-7% proteins
-1.5% solutes
What are some of the principal solutes contained in blood plasma?
-proteins (albumins, globulins, fibrinogen)
-nutrients
-hormones
-respiratory gases
-electrolytes
-waste products
What is hemopoiesis and where does it occur?
-formation of blood cells from pluripotent stem cells
-occurs in red bone marrow
What are the granular leukocytes contained in the formed element portion of the blood?
- neutrophils
- eosinphils
- basophils
What are the agranular leukocytes contained in the formed element portion of the blood?
- T and B lymphocytes and natural killer cells
- monocytes
What is innate (nonspecific) immunity and the first and second line of defence?
-includes the external physical and chemical barriers provided by the skin and mucous membranes (first line of defence against pathogens)
-also includes various internal defences such as antimicrobial substances, natural killer cells, phagocytes, inflammation and fever (second line of defence incase any pathogens get past the first line)
What are the 4 main types of antimicrobial substances that discourage microbial growth which are found in various body fluids?
- interferons
- complement system
- iron-binding proteins
- antimicrobial proteins (AMPs)