exam 1 review Flashcards
where does apex point?
towards the left hip
which layer of the heart wall consumes the most energy?
myocardium
what causes the plateau portion of the action potential in contractile cardiac muscle cells?
an influx of calcium ions
where does the stimulus for the heart’s rhythmic contractions come from?
a pacemaker potential
which structure is responsible for setting the hearts pace?
SA node
Sinoatrial node
why is the SA node the pacemaker?
it depolarizes the fastest
what would happen if the AV node became the pacemaker?
the rhythm would be slower
which heart abnormality has no P waves on an otherwise normal ECG?
junctional rhythm
what does input to the heart from the cardioinhibitory center primarily affect?
the SA node and AV node
what causes the lub sound?
closing of AV valves
what causes the dub sound?
closing of Semilunar valves
which blood vessel components is most critical in regulating systemic blood pressure?
tunica media
the ability to recognize and bind to a specific antigen
Immunocompetence
what contains the majority of the body’s blood volume at any one time?
systemic veins and venules
why has pulse pressure disappeared by the time blood reaches the capillary beds?
the muscular arterioles do not exhibit elastic rebound
what effect does a long period of skeletal muscle inactivity have on blood flow?
it causes blood pooling and slowing of blood flow
the major factor controlling stroke volume during resting periods?
venous return to the heart
what do baroreceptors detect changes in?
stretch in arterial walls
hormone that will help lower blood pressure
atrial natriuretic peptide
why is vasodilation prominent in the skin when a person increases physical activity?
heat is dissipated across the skin from the blood to help cool the body
primary mechanism driving filtration in capillary beds?
hydrostatic pressure within the capillaries
what creates capillary colloid osmotic pressure?
nondiffusible plasma proteins
anaphylaxis
a severe allergic reaction
where does blood from the digestive organs empty into before going through the liver?
hepatic portal vein
major vessel delivering deoxygenated blood to the lungs
pulmonary trunk
which vessel receives blood drainage from the liver and returns it to the heart?
inferior vena cava
what portion of the hemoglobin does oxygen bind to?
iron atom
what does an elevated neutrophil count indicate?
an acute bacterial infection
antihistamine counters the actions of which white blood cells?
basophils
the progenitor of platelets
megakaryocyte
bleeding disorder caused by any condition that suppresses of destroys the red bone marrow
thrombocytopenia
what is a buboe?
a swollen lymph node
largest lymphoid organ
spleen
function of red pulp
filter out worn out blood erythrocytes
activated B cells that produce antibodies
plasma cells
the process of attaching complement proteins to the bacterial cell wall to enhance phagocytosis
opsonization
proteins that make it possible for our immune system to differentiate between our cells and those that are foreign
MHC
what can become antigenic if they attach themselves to larger proteins?
haptens
cells responsible for tissue graft rejection
cytotoxic T cells
how are T cells introduced to antigens?
antigen-presenting cells link antigenic peptides to MHC proteins to which T cells will attach
CD4 cells turn into what?
helper T Cells
what do CD8 cells turn into
cytotoxic T cells
where are lymph nodes found
inguinal, axillary, cervical
what is the P wave?
atrial depolarization
what is the femoral vein once inside the pelvis?
internal iliac
what is the organ that regulates red blood cell production?
kidneys
how are acquired bleeding causes?
impaired liver function
which cells are lost when someone has AIDS
T Helper Cells
main factor causing vasoconstriction
nitric oxide (NO)
where does blood exit the spleen?
the hilum
how do neutrophils cling to the walls of the capillaries?
margination
free floating clot
embolus
what converts fibrinogen to fibrin
thrombin
what cells indicate a rejection of a transplant
cytotoxic T cells
1st step of homeostasis
vascular spasm
how are T cells activated?
by the antigen presenting cells and co-stimulation
what are clone cells?
plasma cells, ( B lymphocytes)
what is the breakdown of a clot called?
fibrinolysis
lymphatic organ that increases in size through childhoos
thymus
what are monocytes in the bloodstream called?
macrophages
proteins released by virus infected cells?
interferons
arteries that supply the large and small intestine
superior and inferior mesenteric
2 main deep veins of the leg
anterior and posterior tibial vein
what does an increase in the mean arterial pressure causes in brain vessels?
contriction
blood vessel that is the immediate inferior continuation of the external iliac artery
femoral artery
The complete circle of connecting vessels in the brain
circle of Willis/cerebral arterial circle
valve that prevents backflow into the right atrium
tricuspid valve
what do CD4 cells become after activation?
T helper Cells
harmful or disease causing microogranisms
pathogens
a lymph organ that stores blood platelets
spleen
type of immunity directed against pathogens in the extracellular fluid
Humoral
the part of the spleen that is made of reticular fibers that trap old erythrocytes
red pulp
where does the thoracic duct empty into?
left subclavian vein
Which cells are the first white blood cells to arrive at a site of tissue damage?
neutrophils
CD4 cells bind to which MHC proteins?
class II
which lymphatic organs have blind-ended structures called crypts?
tonsils
Inflammation is part of which line of defense?
second
isolated clusters of lymph follicles found in the wall of the small intestine
Peyer’s patches
Your patient has no blood flow to the right arm and the right side of the head. Which blood vessel do you think is most likely blocked?
Brachiocephalic trunk
Vasodialation is due to which action of vascular smooth muscle?
relaxation
Define end systolic volume(ESV)
the volume of blood remaining in a ventricle at the end of the ejection phase
What effect do signals from the cardioinhibitory center have on the heart rate?
decrease it
During which part of the cardiac cycle are both the bicuspid and tricuspid valves open?
Ventricular filling
What effect does thyroxine have on the heart rate?
Leads to an increaseof the heart rate
Which heart valve has three flaps (cusps) and prevents backflow into the left ventricle?
Aortic valve
what chamber does the anterior surface of the heart consist mostly of?
rights ventricle
