blood & immune system lecture 1 Flashcards
blood consists of what 3 components?
1) erythrocytes
2) leukocytes
3) platelets
what are erythrocytes?
RBC (important for O2 transport)
what are leukocytes?
WBC (immune systems mobile defence unit)
what are platelets?
cell fragments (important in homeostasis)
what is homeostasis?
equilibrium, balance
what are the 3 physiological roles of blood?
- carrying O2, nutrients, hormones, metabolic wastes, heat
- regulation of body temp, pH
- protection through clotting & immunoglobulins
what are the components of plasma?
1) water
2) electrolytes
3) nutrients, wastes, gas, hormones
what are the 3 plasma proteins?
1) albumins
2) globulins
3) fibrinogen
what is albumin?
transport substances, contribute to colloid osmotic pressure (non-specific)
what are the 2 types of globulins?
1) alpha & beta
2) gamma
what are alpha & beta globulins?
transport water-insoluble substances
- includes clotting factors and inactive precursor
molecules
- Specific (e.g. cholesterol, iron, complement, etc…)
what are gamma globulins?
antibodies
what is fibrinogen?
an inactive precursor for a clot’s fibrin meshwork
what is the percentage of body weight that accounts for blood?
8%
how many litres of blood does a female have?
5 L
how many litres of blood does a male have?
5.5 L
plasma has what percentage of water?
90%
what is the function of water in plasma?
water is a transport medium & carries heat
what is the function of electrolytes in plasma?
- membrane excitability;
- distribute fluid by osmosis between ECF and ICF;
- buffer pH changes
- Most abundant electrolytes are sodium (Na+) and chloride (Cl-)
what are the most abundant electrolytes in plasma?
most abundant electrolytes are sodium (Na+) and chloride (Cl-)
what is the function of nutrients, wastes, gases, hormones in plasma?
- transported in the blood
- blood CO2 plays a role in acid–base balance
what is the most abundant protein in the body?
collagen
what is the most abundant protein in the blood?
albumin
erythrocytes
5 billion RBC per litre of blood
- donut shaped
what is the function of erythrocytes?
carry oxygen to live & generate ATP constantly
what is the function of plasma proteins?
exert an osmotic effect important in the distribution of the ECF between the vascular and interstitial compartments; buffer pH changes
what is the structure of erythrocytes?
flattened disk provides larger SA which is directly proportional to the rate of diffusion
why is SA indirectly proportional to thickness of the membrane?
thicker plasma membrane = slower diffusion of plasma mem
does RBC have a thin or thick plasma membrane?
RBC have a thin plasma membrane to allow faster diffusion of oxygen
hemoglobin is made up of how many subunits?
4 subunits - highly folded polypeptide chains
2 alpha chains & 2 beta chains
how many oxygen s can a RBC carry?
1 billion oxygen molecules
how many molecules can hemoglobin (Hb) transport?
4 O2 molecules
heme
4 iron-containing non-protein groups
what is globin?
4 highly folded polypeptide chains
what is erythropoiesis?
replenish dying RBC with new
can RBC divide?
NO, spleen removes old RBC
where is erythropoietin made?
in the kidney
