Blood
Functions
Transportation: water, gases, nutrients, hormones, enzymes, electrolytes, wastes
Regulation: pH, temperature, water balance
Protection: blood clotting, defense: phagocytic cells, interferons, complement
Composition
A connective tissue with components readily seen when blood is centrifuged:
Plasma(~55!: soluble materials (mostly water!" lighter (top of tube!
#ormed elements (~$5!: cells (heavier so at bottom of tube!
%ostly red blood cells (RBCs!
&uffy coat: site of white blood cells (WBCs!, platelets
Composition
Plasma: Liquid Portion of Blood 'ater: )*5
Plasma proteins: + Albumin (5$!: function in osmosis" carriers lobulins (-.!: serve as antibodies #ibrinogen (+!: important in clotting
/ther: )*5
0lectrolytes, nutrients, gases, hormones, vitamins, waste products
Formed Elements 1* 2ed &lood 3ells (2&3s! 11* 'hite blood cells ('&3s! A* ranular leu4ocytes )* eutrophils 6* 0osinophils -* &asophils
&* Agranular leu4ocytes )* 7ymphocytes and natural 4iller (8! cells 6* %onocytes
111 Platelets
Formation of Blood Cells
Erythrocytes (RBCs)
Hemoglobin (red pigment!
2&3 count: about 5 million9l
3arries .*5 of / 6 and 6- of 3/ 6 %ale: 5*$ million cells9l" female: $*. million9l
;tructure of mature 2&3
o nucleus9<A so 2&3s live only - to $ mos 7ac4 of nucleus causes biconcave disc shape with e=tensive plasma membrane
Provides for ma=imal gas e=change 1s fle=ible for passing through capillaries
White Blood Cells (WBCs or Leukocytes) Appear white because lac4 hemoglobin
ormal '&3 count: 5,>>>?)>,>>>9l
'&3 count usually increases in infection
@wo maor classes based on presence or absence of granules (vesicles! in them
ranular: neutrophils, eosinophils, basophils
eutrophils usually ma4e up 69- of all '&3s
Agranular: lymphocytes, monocytes
%aor function: defense against
1nfection and inflammation Antigen?antibody (allergic! reactions
WBC Life pan
'&3s: 5>>>?)>,>>> '&3s9l blood
7ife span: typically a few hours to days
Abnormal '&3 counts
7eu4ocytosis: high '&3 count in response to infection, e=ercise, surgery
7eu4openia: low '&3 count
Platelets mega4aryocytes
ormal count: )5>,>>>?$>>,>>>9l blood
#unctions
Plug damaged blood vessels
Promote blood clotting
7ife span 5B days
Blood Groups and Blood Types
2&3s have antigens (agglutinogens! on their surfaces
0ach blood group consists of two or more different blood types
@wo e=amples:
A&/ group has types A, &, A&, / 2h group has type 2h positive (2hC!, 2h negative (2h B!
&lood types in each person are determined by genetics
!B" #roup
@wo types of antigens on 2&3s: A or &
@ype A has only A antigen @ype & has only & antigen @ype A& has both A and & antigens @ype / has neither A nor & antigen
@ypically blood has antibodies in plasma
@hese can react with antigens @wo types: anti?A antibody or anti?& antibody &lood lac4s antibodies against own antigens
@ype A blood has anti?& antibodies (not anti?A! @ype A& blood has neither anti?A nor anti?& antibodies
!B" #roup
Rh Blood #roup
ame 2h: antigen found in rhesus mon4ey
2h blood types
1f 2&3s have 2h antigen: 2h C
1f 2&3s lac4 2h antigen: 2h B
Antibodies develop in 2h? persons after first e=posure to 2hC blood in transfusion (or pregnancy hemolytic disease of newborn!
$ransfusions
1f mismatched blood (Dwrong blood typeE! given, antibodies bind to antigens on 2&3s hemolyze 2&3s @ype A& called Duniversal recipientsE because have no anti?A or anti?& antibodies so can receive any A&/ type blood @ype / called Duniversal donorsE because have neither A nor & antigen on 2&3s so can donate to any A&/ type
%isleading because of many other blood groups that must be matched