BIOS 213 chapter 16

blood characteristics

denser than water

38 degrees celcius

pH 7.35-7.45

bright red with high oxygen content, dark red with low

5-6L in men bodies, 4-5 in women

functions of blood

transportation- gases, waste, nutrient

regulation- fluid homeostasis, pH, body temp

protection- clotting, defensive responses

main components of blood

55% plasma

45% formed elements

buffy coat

contains white blood cells and platelets

normal hematocrit

40-54% in men

38-46% in women

number platelets in blood

150,000-400,00

number leukocytes in blood

5000-10,000

number erythrocytes in blood

4.8-5.4 million

percentage of neutrophils in leukocytes

60-70%

percentage of lymphocytes in leukocytes

20-25%

percentage of monocytes in leukocytes

3-8%

percentage of eosinophils in leukocytes

2-4%

percentage of basophils in leukocytes

0.5-1%

most abundant plasma protein

albumin

blood plasma contents

92% water

8% solutes- 7% proteins

granular white blood cells

neutrophils, eosinophils, basophils

agranular white blood cells

lymphocytes and monocytes

formation of blood cells

hemopoiesis, occurs in red bone marrow, all derived from pluripotent stem cells

myeloid stem cells

form into RBCs, platelets, neutrophils, eosinophils, basophils, monocytes

lymphoid stem cells

form into B,T lymphocytes and natural killer cells

path of erythrocytes formation

pluripotent cell, myeloid stem cell, committed progenitor cell, proerythroblast, reticulocyte, erythrocyte

path of platelet formation

pluripotent cell, myeloid stem cell, committed progenitor cell, megakaryoblast, megakaryocyte, platelets

hemopoietic growth factors

erythropoietin, thrombopoietin, cytokines

erythropoietin

A hormone produced and released by the kidney that stimulates the production of red blood cells by the bone marrow.

thrombopoietin

hormone from liver stimulates platelet formation

cytokines

Chemicals released by the immune system communicate with the brain.

interleukin 1- stimulating WBC

GCSF- stimulates neutrophils

GMCSF- stimulates monocytes and eosinophils

RBC characteristics

biconcave disc. lack nucleus- larger surface area

anerobic ATP generation- don't use oxygen they transport

plasma membranes determine blood type

hemoglobin structure

4 polypeptide chains with 4 hemes with Fe+2, each heme binds to one oxygen

erythropoiesis

pluripotent stem cells -> myeloid stem cells -> proerythroblasts, divide multiples times, eject nucleus -> reticulocyte, leaves bone marrow and enters blood -> mature blood cell within 1-2 days

erythropoiesis regulation

negative feedback loop with amount of oxygen delivered to tissue

formation and destruction of red blood cells

see figure 16.6

basophils

granular, stain as blue/purple granules with no nucleus visible

eosinophils

granular, stain as red/orange granules with two lobed nucleus

neutrophils

granular, stain as pale purple granules with multi lobed nucleus

bands indicate young age, more lobes indicate old age

lymphocytes

agranular, stain as tiny and dark

include T cells, B cells, and natural killer cells

monocytes

agranular, stain as blue/grey cytoplasm with kidney shaped nucleus

once left circulatory system, differentiate into fixed and wandering macrophages

WBC in bacterial infection

neutrophils respond quickly, lysozymes kill bacteria and defensins have antibiotic activity

monocytes respond strongly and clean up debris

seasonal allergies

mostly basophils attack

parasitic worm infections

mostly eosinophils attack

B lymphocytes

develop in plasma cells that secrete antibodies, attack bacteria

T lymphocytes

attack viruses, cancer, transplanted tissue

natural killer cells

attack arising tumor cells

hemostasis

stopping blow flow done by:

vascular plug, platelet plug, coagulation

vascular spasm

immediate contraction of vessel walls to stop blood flow to damaged area

platelet phase

1. adhesion- platelets stick to exposed collagen fiber

2. release action- platelets release ADP, thromboxane A2, serotonin to attract more platelets to the area

3. aggregation- platelets stick together and block the damage

extrinsic pathway

1. trauma released tissue factor

2. TF +Ca+2 -> activated factor 10

3. Activated factor 10 +factor 5 + Ca+2 -> prothrombinase

intrinsic pathway

1. exposed collagen activates factor 12

2. factor 12 + Ca+2 -> activated factor 10

3. activated platelets -> phospholipids +Ca+2 -> activated factor 10

4. factor 10 +Ca+2 -> prothrombinase

common pathway

1. prothrombinase +Ca+2 turns prothrombin to thrombin

2. thrombin +Ca+2 turn fibrinogen to fibrin

3. thrombin activates factor 13 to strengthen fibrin

clot retraction

fibrin clot tightens and pulls damaged edges closer together, permanent repair takes place

fibrinolysis

dissolution of clot

plasminogen activated to plasmin which digests fibrin and inactivates factor 5+13, prothrombin, fibrinogen

anticoagulants in blood

antithrombin- blocks factor 13 and prothrombin

heparin- blocks thrombin

activated protein C- inactivates factors 5+13

vitamin K in blood clotting

helps activate factors 2+ 7 +9 +10

blood typing

see notes

agglutination

clumping of red blood cells- not the same as clotting