Chapter 7 Flashcards
What are 3 major circulatory elements?
- A pump (heart)
- Channels or tubes (blood vessels)
- A fluid medium (blood)
______ generates pressure to drive blood through vessels.
Heart
What must meet metabolic demands?
Blood flow
What are the 6 major functions of the cardiovascular system? (DRTTAI)
- Delivers O2, nutrients
- Removes CO2, other waste
- Transports hormones, other molecules
- Temperature balance and fluid regulation
- Acid base balance
- Immune function
The right side of the heart utilizes ______ circulation.
Pulmonary
The right side of the heart pumps ________ blood from body to lungs.
Deoxygenated
The left side of the heart utilizes _____ circulation.
Systematic
The left side of the heart pumps ______ blood from lungs to the body.
Oxygenated
What is the myocardium?
Cardiac muscle
Which has thicker walls, Left or right ventricle?
Left ventricle
Why does the left ventricle have thicker walls?
Hypertrophy due to exercise
T/F: Myocardium needs blood.
True
What supplies the right side of the heart?
Right coronary artery
What supplies the left side of the heart?
Left (main) coronary artery
What is atherosclerosis?
Coronary artery disease
Which cells are described to be:
- large, long, unbranched, multinucleated
Skeletal muscle cells
Which cell is small, short, branched and has one nucleus?
Myocardial
Which cell has intermittent and voluntary contractions?
Skeletal muscle
Which cell has continuous and involuntary rhythmic contractions?
Myocardial cells
Which cell has Ca+2 which is released from SR?
Skeletal muscle
Which cell has calcium-induced calcium release?
Myocardial cells
What are the 4 steps of calcium induced calcium release? (ADEI)
- AP spreads along sarcolemma down T-tubules
- DHP receptors in T-tubule are stimulated and open
- Extracellular Ca+2 to enter cell, but insufficient to cause contraction
- Instead, triggers ryanodine receptors on SR to release Ca+2
How many fiber type(s) are within myocardial cells?
1
Cardiac muscle fibers connected by regions called ________.
Intercalated discs
What holds cells together?
Desmosomes
What rapidly conducts action potentials?
Gap junctions
What is the unique ability of cardiac muscle being able to generate its own electrical signal?
Spontaneous rhythmicity
T/F: Spontaneous rhythmicity allows cardiac muscle contraction without any external stimulation.
True
What is the pathway of electrical impulse in cardiac muscle?
Right atrium —> throughout entire heart
What is the starting point of the heart?
Sinoatrial node (SA node)
Where and what is the fastest intrinsic firing rate?
SA node & about 100 beats/min
What is the term used to describe special cardiac cells generating and spreading electrical signal?
Spontaneous rhythmicity
What are the 4 locations of spontaneous rhythmicity? (SAAP)
- SA node
- AV node
- AV bundle (bundle of His)
- Purkinje fibers
What initiates contraction signal in the cardiovascular system?
SA Node
What delays and relays signals to ventricles in the cardiovascular system?
AV Node
What stimulates RA, LA contraction?
SA Node
What allows RA and LA to contract before RV and LV?
AV Node
What relays signal to RV and LV?
AV bundle
What sends signals into RV and LV?
Purkinje fibers
Purkinje fibers are terminal ____ of right and left bundle branches.
Branches
Which fiber stimulates RV, LV contraction?
Purkinje fibers
Which division controls:
- Decreases force of contraction
- Decreases HR below intrinsic HR
Parasympathetic control
Elite endurance athlete: ____ beats/min
35
Which division controls:
- Increase force of contraction
- Increases HR above intrinsic HR
- Determines HR during physical, emotional stress
- Maximum possible HR: 250 beats/min
Sympathetic control
_____: relaxation phase of the cardiac cycle.
Diastole
____: contraction phase of the cardiac cycle
Systole
Which cardiac cycle phase is being described:
- Chambers fill with blood
- Twice as long as systole
Diastole
Which cardiac cycle is being described:
- Ejection of blood
Systole
What is the cycle where all mechanical and electrical events that occur during one heartbeat?
Cardiac Cycle
The Ventricular systole is ___ of cardiac cycle time?
1/3
The Ventricular diastole is ____ of cardiac cycle time.
2/3
What is the volume of blood pumped in one heartbeat?
Stroke Volume
How do you calculate SV?
EDV - ESV = SV
What is the normal Ejection fraction for healthy, active young adult at rest?
60%
What is the term for total volume of blood pumped per minute?
Cardiac Output
Resting cardiac output:
About 4.2 to 5.6 L/min
What carries blood away from the heart?
Arteries
What controls blood flow and feed’s capillaries?
Arteriole
What is the site of nutrient and waste exchange?
Capillaries
What collects blood from capillaries?
Venules
What carries blood from Venules back to heart?
Veins
What is the pressure exerted by blood on arterial walls?
Blood pressure
What is the highest pressure in artery during systole?
Systolic pressure
What is the lowest pressure in artery (during diastole)?
Diastolic pressure
What is the average pressure over entire cardiac cycle?
Mean Arterial Pressure
T/F: Blood flow is required by all tissues.
True
What is the force that drives flow?
Pressure
What is the force that opposes flow?
Resistance
What is the easiest way to change flow?
Change resistance
When the artery constricts
Vasoconstriction
When the artery widens/opens.
Vasodilation
What is also known as resistance vessels?
Arteriole s
What is the site of most potent VC and VD?
Arterioles
T/F: Arteriole walls can respond to local control mechanisms.
True
What is the ability of local tissues to constrict or dilate Arterioles that serve them?
Intrinsic control
How many types of intrinsic control are there?
3
