cardiac system Flashcards
what are the functions of blood
- transport respiratory gases, nutrients, waste, hormones, heat
- regulation of pH, ion composition and volume of blood
- protecting with immune defences and hemostasis
what is the colour of blood, with O2 and without
bright red (saturated w oxygen)
dark red (unsaturated)
what is plasma
- watery extracellular matrix
- the fluid portion of blood
what does plasma contain
- dissolved substances
- 91% water, 8.5% solutes
what percentage does plasma make up of the total blood composition
55%
what are proteins only found in blood called
plasma proteins or dissolved proteins
what are the proteins found in plasma
albumin
fibrinogen
globulin
albumin: functions, percentage it makes up of proteins
- 60% of plasma proteins
functions - contributes to osmotic pressure of blood
- transports fatty acids, steroids, hormones,
- acts as a buffer
what is the function of fibrinogen
- blood clotting
- turns from fibrinogen (soluble) to fibrin (insoluble)
what is the function of globulin
- transports proteins for metals, fats and thyroid hormone
- works as an antibody
what is immunoglobin
type of globulin produced during immune responses
what is found in the formed elements of blood?
- cell and cell fragments
the formed elements make up what percentage of total blood composition
45%
what is formed elements made up?
- 99% red blood cells
- 1% white blood cells and platelets
what is the function of rbc
- transports oxygen from lungs to body cells
- transports CO2 from body cells to lungs
- contain hemoglobin
what is the function of white blood cells
- protect body from pathogens and foreign substance
- contribute to body’s defence mechanism
what is the function of platelets
release chemicals that promote blood clotting when blood vessels are damaged
out of the formed elements, what are true cells
- wbc
- rbc and platelets have lost true ell function
what are platelets
- cell membrane wrapped cytoplasmic pieces
- no nucleus
what is hematocrit
- percentage of total blood volume occupied by rbc
- carrying capacity blood
what is he hematocrit in women vs men
women: 42%
men: 47%
why do men have a higher hematocrit than women
- because they have more testosterone, which synthesis a hormone that inc production of rbc
what are densities of the components of blood
formed elements > buffy (wbc and platelets) > blood plasma
how does plasma contribute to homeostasis
- plasma is in equilibrium with IF –> it controls the composition of IF
what’s the difference between IF and plasma
plasma contains proteins, IF doesn’t
what is hemostasis
stoppage of bleeding
how do platelets contribute to hemostasis
- swell and stick together
- forms temporary plug to stop bleeding
how does fibrin contribute to hemostasis
- fibrinogen is turn into fibrin when triggered by wound signals
- platelets stick to fibrin mesh
what is serum?
plasma without fibrin
- it wont clot
what is the pericardium
double serous membrane that forms the pericardial sac and epicardium
what are the 2 layers of the pericardium
fibrous pericardium and serous pericardium
what is the fibrous pericardium
- outer protective layer
- made of dense CT
- fused to serous pericardium
what is the serous pericardium
- inner layer of the pericardium
- double membrane (parietal and visceral pericardium)
what is the parietal pericardium
- outer serous membrane
- fused to fibrous pericardium
what is the visceral pericardium
- inner serous membrane
- fused to heart
- is the epicardium
what is the pericardial cavity
- contains fluid that reduce friction
- in between serous membrane
what are the 3 layers of the heart wall
epicardium
myocardium
endocardium
what is the epicardium made of
epithelium and CT
what is the myocardium
- middle heart wall layer
- made of cardiac muscles cells and fibrous skeleton, blood vessels and nerves
what is fibrous skeleton
- skeleton collagen and elastic fibers
- support the valves and isolate the atria and ventricles
what is the endocardium
- inner layer of heart wall
- made of simple squamous and CT –> smooth surface
describe the characteristics of cardiac muscles
- parallel elongated muscle cells
- striated
- mono nucleate
- contains intercalated discs with some branching
what are intercalated discs
sieve like structures between cardiac cells that allow ions to pass from one cell to the next
- allows muscles to contract as a unit
what’s the difference between the act pot of the NS and cardiac muscles
- cardiac muscles have prolonged act pot = produces longer contraction
- is automaticity system = heart can initiate contractions on its own
each side of the heart contains what?
- atrium
- ventricle
- av valve
- sl valve
what is the function of the atria
collecting chamber –> receives/collects blood
what is the function of the ventricles
pumping chamber –> discharges/pumps blood
what are the 2 circuits of the heart
pulmonary and systemic
what is the pulomary circuit
- right side
- pumps to the lungs to pick up oxygen and unload carbon dioxide
what is the systemic circuit
- left side
- pumps to the tissues of the body to deliver nutrients and oxygen, and to pick up waste (Co2)
what are the structure that both pumps have
arteries
capillaries
veins
what are facts about both pumps
- work in sequence
- carry equal volumes of blood but aren’t the same length
how are the 2 circuits connected?
capillaries
how is the right side different from the left side?
- produced lower pressure pump –> circuit is shorter
- thinner walls
- crescent shape around wrapping around left ventricle
how is the left side different from the right
- produced greater pressure –> circuit is longer
- thickest walls
- round shaped around wrapping of right ventricle
where are the atrioventricular valves found
between atria and ventricles
what do av valves consist of?
flaps, chordae tendinae, papillar muscles
what are the 2 types of av valves
- tricuspid: right side - 3 sides
- bicuspid: left side - 2 flaps
what is a mitral valve
bicuspid valve
what is the semilunar valve found
between ventricles and vessels
what’s the structure of the sl valve
3 cup like flaps
what are the 2 types of sl valve
- pulmonary: right side
- aortic: left side