introduction to structure and function of blood Flashcards
What is blood made up of?
β plasma (fluid)
βcells (such as red cells, white cells and platelets).
what are properties of red blood cells?
β known as erythrocytes
βbiconcave discs
βthey have no nucleus and do not contain DNA, RNA or mitochondria
what are properties of white blood cells?
β known as leukocytes
βcolorless
βthe two most common types of leukocytes are neutrophils and lymphocytes
Describe the structure of neutrophils
β it is polymorphonuclear, so it has an irregular, multi-lobed nucleus
βit is a granulocyte, which means that it has prominent cytoplasmic granules which are toxic and used for killing microorganisms
List the three different types of granulocytes, and the differences between them.
NEUTROPHILS:
βweakly staining granules
βthe most common type of WBC
EOSINOPHILS:
βgranules stain red with eosin
β make up 1-4% of WBCs
BASOPHILS:
βgranules stain blue/purple with basic dyes
βmake up <0.5% of WBCs
What are the two types of mononuclear cells?
βmonocytes (the largest type of WBC)
β lymphocytes (it has a large nucleus, and not a lot of cytoplasm).
give some properties of platelets?
βknown as thrombocytes βcytoplasmic fragments β no nucleus βmembrane-bound β contain granules
Where do blood cells come from?
βMature blood cells are produced from the stem cells in the bone marrow.
βThe bone marrow contains many immature cells.
what are the
1) ionic constituents of blood (+ve and -ve)
2) fluid components
of plasma?
β fluid containing water, salts, proteins and organic molecules (eg. metabolites, carbohydrates, lipids, etc.)
βIts ionic constituents are positive ions (such as sodium, potassium, calcium, magnesium and hydrogen ions)
βnegative ions (such as chloride, bicarbonate, phosphate, sulphate and organic anions).
What is the difference between plasma and serum?
βPlasma is the fluid component of the whole blood.
βSerum is the fluid left over after blood clotting factors have been removed from the plasma.
Describe the percentage of protein in the plasma.
βplasma is about 7-9% protein.
βover 90% of them is a single protein, albumin.
What are the three main functions of the blood?
β TRANSPORT
β IMMUNITY
β HOMEOSTASIS
What does the blood transport?
β carries oxygen/nutrients to tissues.
β removes CO2/other waste products from tissues.
β transports other substances (eg. hormones) from the sites of production to the sites of action.
Describe an erythrocyteβs role in oxygen transport and carbon dioxide removal.
βErythrocytes transport oxygen from the lungs to the body tissues.
β removal of CO2 from body tissues to the lungs.
βMost of the CO2 is carried as the bicarbonate ion (HCO3-) in the plasma.
give some properties of haemoglobin and give its function
βThe major constituent in red blood cells is the protein Haemoglobin (Hb).
βHb binds oxygen and carries it from the lungs to the tissues.
βHb is a protein tetramer made up of 4 polypeptide chains, 2 Ξ± and 2 Ξ² globin chains.
βEach globin chain carries a haem molecule.
βEach haem holds a ferrous (Fe2+) iron atom.
what are the two forms of haemoglobin and what are their colors?
βOXYHAEMOGLOBIN, when it is fully saturated with O2, making it bright red
βDEOXYHAEMOGLOBIN, when it has lost all of its O2, making it dark red
What is the difference in what the plasma carries and what the plasma proteins carry?
βPLASMA: carries soluble metabolites in solution
βPLASMA PROTEINS: carry substances which are poorly soluble in water (eg. lipids and lipid-soluble hormones and vitamins), they also carry metal ions (eg. Ca2+, Fe2+, Cu2+).
why do plasma proteins need to carry ions?
βthe ions can be toxic
β if you get a bacterial infection, the bacteria need metal ions (especially Fe2+) for growth, so having them bound slows their growth.
how are platelets generated?
cytoplasmic fragments generated from large cells in the bone marrow
what is the difference between ferrous and ferric iron
βferrous iron has lost 3 electrons
β ferric ion has lost 2 electrons
