Chapter 17 Part 2- Blood Flashcards
Leukopoiesis
production of WBCs
What is Leukopoiesis stimulated by?
chemical messengers from bone marrow and mature WBCs
where do all leukocytes originate from?
hemocytoblasts
what is the blood voume level of WBCs?
<1%
how can WBCs leave capillaries?
via diapedsis
How do WBCs move through tissue spaces?
by ameboid movement and positive chemotaxis
Granulocytes
Neutrohils, eosinophils, and basophils
what are granulocytes?
- cytoplasmic granules
- larger and shorter lived than RBCs
- lobed nuclei
- phagocytic
Neutrophils
- most numerous WBCs
- 6hrs -> a few days
- fine granules
- pruple cytoplasm when stained
- graules contain hydrolytic enzymes or defensins
- very phagocytic- “bacteria slayers”
- ANC of 2500-6000 is normal
What WBC is most numerous?
neutrophils
Neutrophil graules contain ______ enzymes or ______
hydrolytic
defensins
what WBC is a bacteria slayer that is very phagocytic?
Neutrophils
Eosinphils
- red staining, bilobed nuceli
- red (acidophilic) Coarse, lysosome-like granules
- digest parasitic worms that are too large to phagocytized
- modulators of immune respone
- 8->12 days, circulate 4/5 days
What WBC is able to digest parasiti worms that can not be phagocytized?
eosinphils
what WBC modulates the immune system?
Eosinphils
Basophils
- rarest WBCs
- large, purplish-black (basophilic) graules contain histamine.
- functionally similar to mast cells
- few hours to a few days
what is the rarest WBC?
basophils
histamine
an inflammatory chemical that a vasodilator and attracts other WBCs to inflamed sites
What WBCs contain histamine?
Basophil
what WBC is similar to mast cells?
basophils
how long is basophils life span?
few hours to a few days
Agranulocyte
lymphocytes and monocytes
what are agranulocytes?
lack visible cytoplasmic granules, have spherical or kidney shaped nuclei
Lymphocytes
-large, dark pruple, circular nuclei with a thin rom of blue cytoplasm
-crucial to immunity
- two types:
T cells and Bcells
What WBC is crucial to immunity?
lymphocytes
a large, dark purple, circular nuclei with a thin blue rim of cytoplasm
lymphocytes
what are the two types of cells in a lymphocyte?
T cells and B cells
what is a t cell?
act against virus infected cells and tumor cells- memory, cytotoxic, regulatory (suppressor, helper, natural killer
how long can memorycells live?
years or atleast months
what is a b cell?
give rise to plasma cells which produce antibodies
Monocytes
- largest leukocyte
- abundant pale blue cytoplasm
- dark purple staining, u- or kidneyshaped nuclei
- leave circulation, enter tissues, and differentiate into macrophasges
- activate lymphocytes to mount an immune response
- hours to day
T cells start the process to what
celluar immunity
monocytes are the largest WBCs? T/f
T
this WBC has an abundant pale blue cytoplasm
monocytes
dark purple staining, u or kidney shaped nuclei
monocytes
this WBC is an actively phagocytic cell that is crucial against viruses, intracellular bacteria parasites, and chronic infection
monocytes
what WBC can differentiate into macrophages>
monocytes
which WBC leave the circulation and go adventure for the nasty infection?
Monocytes
What WBC activate lymphocyte to mount an immune response?
monocytes
leukopenia
abnormally low blood count- drug induced
cancerous condition involving WBCs
-named according to abnormal WBC clone involved
Leukemias
myelocytic leukemia
involve myeloblasts
lymphocytic leukemia
involves lymphocytes
what leukemia involves blast-type cells and primarily affects children
acute leukemia
what leukemia is more prevalent in older people
chronic leukemia
leukemia
- bone marrow totally occupied w cancerous leukocytes
- immature nonfunctional WBCs in the bloodstream
- death caused by internal hemorrhage and overwhelming infections
- treatments include irradiation, antileukemic drugs, and stem cell transplants
platelets
- small fragments of megakaryocytes
- formed by thrombopoietin
- blue staining outer region, purple granules
- granules contain serotonin, Ca2+ enzymes, ADP, platelet derive growth factor
- form temp. plug that eal breaks in B.V
- circulating platelets are kept inactive and mobile by NO and prostacyclin from endothelial cells of blood essels
what are small fragements that are made of megakaryocytes?
platelets
platelets are regulated by
thrombopoietin
what are the granules in a platelets created of>
serotonin, Ca2+, enzymes, ADP, and platelet derived growth factor
what type of ADP do platelets granules have?
a chemical,not energy
what forms a temporary plug that helps seal breaks in blood vessels?
platelets
circulating platelets are kept _______ and _____ by NO (nitrous oxide) and prostacyclin from endothelial cells of BV
inactive and mobile
Hemostasis
3 steps
- vascular spasm
- platelets plug formation
- Coagulation (blood clotting)
Step 1- vascular spasm
smooth muscles contract, vasoconstriction, slowing down blood flow
step 2- platelet plug formation
collagen fibers get exposed’ platelets adhere. platelets release chemicals that make nearby platelets sticky; platelet plug formation
step 3- coagulation
fibrin forms a mesh that traps RBC and platelets, forming the clot
vascular spasm
vasoconstriction of damaged BV
vasoconstriction is triggerd by
- direct injury
- chemicals released by endothelial cells and platlets
- pain reflexes
HEMOSTASIS IS A WHAT FEEDBACK MECHANISM
POSITIVE
platelet plug formation
@ the site of injury platlets,
- stick to exposed collagen with the help of VON willibren factor, a plasma protein
- swell, become spiky and sticky, release chemical messengers (their granule)
What two chemicals are released in platelet plug formation
-ADP and serotonin
how is ADP used as a chemical messenger in platlet plug formation
casues more platlet to stick and release their contents
where are the two chemical messangers in platelet plug formation from?
the granulocyte from platelets
serotonin and thromboxane A2lug formation?
enhances vascular spasm and more platelet aggregation
coagulation
a set of reaction in which blood is transformed from a liquid to a gel
-reinforces the platelet plug formation
3 phases of coagulation
- prothrombin activator is formed (intrinsic and extrinsic pathways)
- prothrombin is converted into thrombin
- Thrombin catalyzes the jioining of fibrinogen to form a fibrin mesh
phase 1 of coagulation - two pathways
intrinsic and extrinsic
the intrinsic athway of coagulation
triggered by tissue damaging events
-activated platelets, collagen
the extrinsic pathway of coagulation
is triggered by exposure to tissue factor(TF) or plasma factor (an extrinsic factor) outside the circulatory system (due to damaged vessel)
coagulation phase 2; pathway to thrombin
- prothrombin activator (12 coagulation factor) catalyzes trainformation of prothrombin (a glycoprotein found in plasma) to the active anzyme thrombin (which changes fibrinogen into fibrin)
coagulation phase 3- common pathway to the fibrin mesh
- thrombin convert fibrinogen into fibrin
- firin strands form structural base of clot
- fibrin causes plasma to become gel like trap for formed elements
- thrombin (w Ca2+) activates cloting factor XIII -cross link fibrin
- strengthen and stabilize the clot
clot retraction is _____ of a blood clot over a number of days
shrinking
-edges of the BV wall at injury are slowly brought together again
___ and _____ in platelets contract in 30-60 min
actin and myosin
platelets pull on the _____ strands, squeezing ____ from the clot
fibrin, serum
clot repair
platelet derived growth fctor (PDGF) stimulates divison of smooth muscle cells and fibroblasts to rebuild BV walls
____________ stimulates endothelial cells to multiply and restore the endothelial lining
vascular endothelial growth factor
fibrinolysis
- prevents blood clots from growning
- begin in 2 days
- plasminogen in clot converted to plasmin
- plasmin is a fibrin-digesting enzymes
what cleaves the fibrin mesh at various places, leading to circulating fragments that are clared by other proteases or by the kidney and liver
fibrinolysis
_____ in clot is converted to plasmin
plasminogen
____ is a fibrin digesting enzyme
plasmin
factors preventing undesirable clotting (platelets adhesion is prevented by
- smooth endothelial lining of BV
- antithrombic substances nitric oxide and prostacyclin secreted by endothelial cells
- vit E quinine, which acts as a potent anticoagulant
___________ which act as a potent anticoagulant
Vit. E quinine
hemostasis disorders
thromboembolytic disorders- undesirable clot formation
bleeding disorder- abnormalties that prevent normal clot formation
thromboembolytic disorders
undesirable clot formation
bleeding disorder
abnormalties that prevent normal clot formation