RAT 3 Flashcards
what are the two regions of the adrenal gland?
- adrenal cortex
- adrenal medulla
what are the three zones of the adrenal cortex?
- zona glomerulosa
- zona fasciculata
- zona reticularis
which zone of the adrenal cortex produces mineralocorticoids?
zona glomerulosa
what do mineralocorticoids regulate?
concentration of certain minerals in the body
what is the main mineralocorticoid?
aldosterone
what is the main role of glucocorticoids?
helps mediate the body’s response to stress
what do the glucocorticoids regulate?
blood glucose
what is the name of the main glucocorticoid?
cortisol (hydrocortisone)
what are the three primary targets of cortisol?
- liver, muscle, adipose tissues
what effect does cortisol have in each organ?
- gluconeogenesis in the liver
- release of amino acid’s from muscle tissue
- release of fatty acids from adipose tissue
how would each effect help with stress?
increases the availability of fuel molecules
what organ produces CRH?
hypothalamus
what is the target for CRH?
anterior pituitary
what is the effect of CRH?
stimulates the release of ACTH
what organ produces ACTH?
anterior pituitary
what is the target for ACTH?
zona fasciculata
what is the effect of ACTH?
stimulates cortisol production
what organ produces cortisol?
adrenal glands (zona fasciculata)
are platelets cells? if not, what are they?
no, small fragments of cells surrounded by a plasma membrane
what is a megakaryocyte?
cell located in the bone marrow from which platelets are derived
explain how platelets form from megakaryocytes
small pieces break off into the cell creating new formed platelets
what is hemostasis?
the process by which blood loss is stepped from a damaged blood vessel
what are the five steps of hemostasis?
- vascular spasm
- platelet plug formation
- coagulation
- clot formation
- thrombolysis
describe the first step of hemostasis?
blood vessel diameter is decreases which leads to a local reduction in blood pressure and blood flow
what is the second step of hemostasis?
platelets adhere to an injury site and form a platelet pluf
what is the second step of hemostasis?
platelets adhere to an injury site and form a platelet plug
what is the primary component of a platelet plug?
platelets
why do platelets adhere to an injury site?
collagen fibers and chemicals become exposed
factors released by platelets attract nearby ______________ and cause them to ___________________
- platelets
- clump together
this causes platelets to clump together or ____________
aggregate
this aggregation forms the _______________ _________ that temporarily seals an injured vessel.
platelet plug
what is the third step of hemostasis?
coagulation - where fibrin converts the soft, liquid platelet plug into a more solid mass
what is the name of the protein that forms a blood clot?
fibrin
hat is the inactive form of fibrin called?
fibrinogen
what is the name of the process of the formation of a blood clot?
coagulation
what are clotting factors?
enzymes produced by the liver that circulate in the blood in their inactive forms
what are the two pathways of starting the coagulation cascade?
- intrinsic pathway (contact activation pathway)
- extrinsic pathway (tissue factor pathway)
why is the intrinsic pathway named “intrinsic”?
all the factors required for it to proceed are located in the blood
hat is the first step in the intrinsic pathway?
exposed collagen fibers activate factor XII
what ion is needed for this coagulation cascade?
calcium ions
what is the last factor activated in the intrinsic pathway?
factor X
why is the extrinsic pathway named “extrinsic”?
initiated by a factor outside the blood
what ion is needed for this coagulation cascade?
calcium ions
what is the last factor activated in the extrinsic pathway?
factor X
what is the name of the pathway that continues the coagulation cascade after the intrinsic and extrinsic pathways converge?
common pathway
what is the function of prothrombin activator?
converts prothrombin into thrombin
what is the function of thrombin?
turns fibrinogen into fibrin
what is the 4th part of hemostasis? describe it.
clot retraction: brings the edges of the wounded vessel closer together (like sutures)
after healing takes place, what is the name of the process in which are unnecessary clot is dissolved?
thrombolysis
prostacyclin prevents platelets from sticking to intact blood vessel. what cells produce prostacyclin?
endothelial cells
where are endothelial cells produced?
blood vessels
what is an anticoagulant?
substances that inhibit coagulation
name two anticoagulants.
- antithrombin-III
- heparan sulfate
how does antithrombin-III prevent clots?
binds and inhibits the activity of both factor Xa and thrombin
name a disease caused by a clotting protein deficiency
hemophilia A or hemophilia B
what is the term for the condition that results in the formation of an inappropriate clot?
thrombosis
what is the name of the inappropriate clot?
thrombus
if a piece of the clot breaks off and travels in the blood stream it is known as a ______________________ or an embolus
thromboembolus
what is the most serious complication of a deep vein thrombosis?
pulmonary embolism
what are the surface markers found on most cells including RBC’s?
antigens
what are the two groups of antigens we focus on that are found on RBC’s?
- ABO blood group
- Rh blood group
what are the two antigens in the ABO blood group?
antigen A and antigen B
what are the four ABO bloof types?
- type A
- type B
- type AB
- type O
what antigen is in the Rh blood group?
Rh antigen
what are the two Rh blood types?
- Rh positive
- Rh negative
what are the eight blood types when ABO and Rh are combined?
- AB+
- AB-
- A+
- A-
- B+
- B-
- O+
- O-
what is agglutination?
the clumping together
when does agglutination take place?
when antibodies interact with bound antigens
what ultimately occurs when RBC’s agglutinate?
erythrocyte hemolysis
antigens on your own cells are recognized as “______________________”
self-antigens
do you typically produce antibodies that bind to your own antigens? why or why not?
no because if you did, your antibodies would bind your own antigens
anti-A antibodies and anti-B antibodies are pre-formed. what does that mean?
present in the plasma even if the individual has never been exposed to those antigens
what blood type has anti-a antibodies?
type B
what blood type has anti-b antibodies?
type A
when do anti-Rh antibodies form?
only if a person has been exposed to blood containing Rh antigens
which vessels supply most of the arterial blood to the head and neck?
right and left common carotid arteries
what are the two branches of each common carotid artery?
- external carotid artery
- internal carotid artery
what structure does the external carotid artery supply with blood?
head and face
what structure does the internal carotid artery supply with blood?
the brain
where is the carotid sinus located?
- ascend through the neck by passing through the transverse foramina in the transverse processes of the cervical vertebra
- branches of the right and left subclavian arteries
what do the vertebral arteries supply?
the brain
