missing que cards Flashcards
which vessels in the heart enter through the atriums?
these are the two upper chambers in the heart
right= deoxygenated blood from vena cava
left = oxygenated blood from the pulmonary vein
what are ventricles and what vessels enter through here
two lower chambers of the heart
- right = deoxygen blood from atrium
- left = oygenated blood from atrium
describe the pathway of a RBC form the atrium to the aortic arch
- right atrium
- tricupsid valve
- atrium
- right ventricle
- pulmonary semilunar valve - pulmonary artery
- pulmonary vein
- left atrium
- mitral valve
- left ventricle
- aortic semilunar valve
- aorta
what is the purposes of the valves in the heart?
open to allow blood to enter the next chamber or trunk and close to ensure there is no back flow
why is elasticity and contractility of arteries important?
- when the heart pumps blood, arteries fill up and stretch to accommodate the extra blood
- as ventricles relax, arteries force blood forward
Trace a drop of blood through major arteries and veins from the aortic arch through its systemic circulatory route to your right ankle and back to your heart again.
- aorta (descends down)
- hepatic artery (liver)
- renal artery (kidneys)
- common iliac artery (pelvis)
- divide into arterioles
- further divide into capillaries
- capillaries join together to form venules
- venules join to form right femoral vein
- right iliac vein
- renal vein
- hepatic vein
- join to form inferior vena cava
- right atrium of heart
Explain how blood returns to the right atrium. Why should one “cool down” after exercise rather than stop suddenly?
- enters through vena cava (vein)
- blood pressure increases during excersise and redirects blood to working muscles
- we cool down to allow parasympathetic nervous system to take over, blood vessels relax and blood flows to abdomen to slow heart rate
- gradually allows heart rate to return to normal
Why is the wall of the left ventricle thicker than the right?
systemic circulation is a higher pressure system than pulmonary circulation
left side needs to pump to rest of body
Why are heart valves important? Can the heart function with leaky valves?
controls/regulates blood flow and prevents blood from going backwards
- may lead to serious heart problems
Why are artery walls so much thicker than those of corresponding veins?
- extra strength & elasticity to deal with surges of blood
- also needs to maintain pressure to keep blood flowing
Blood pressure measurement (step by step) 11 steps
- use take to measure circumference of relaxed arm (use correct size)
- use a sphygmomanometer (blood pressure cuff and recording manometer) to measure major artery (brachial artery) which is 1 inch above elbow joint
- pump to 100mm Hg
- place stethoscope over the artery
- release the pressure in the bag to 0 by rotating pressure control knob in counter clockwise
- korotokoff sounds become audible as pressure declines and sound disappears
7) phase 1: first appearance of faint clear tapping sounds which gradually increase - this represents the SYSTOLIC BP
8) phase 2: period during which murmur of swishing quality is heard
9) phase 3: period during which sounds deeper and increase in intensity
10) phase 4: period marked by distinct, abrupt muffling of sound so that soft, blowing quality is heard
11) phase 5: point at which sounds disappear - represents DIASTOLIC BP
When measuring blood pressure you must listen for Korotkoff sounds at the brachial artery using a stethoscope. Why can’t you hear these sounds before the cuff is inflated?
pressure in the bag-cuff system is higher than the systolic pressure exerted on the walls of the brachial artery, SO it is constricted and no blood will flow to the lower arm
If blood pressure was measured at the level of a subject’s calf rather than at the level of the upper arm, would you expect the blood pressure readings to be different?
- no, because BP is greatest closest to the heart
- BP would have decreased as it travels to other major arteries
4 sources of error when recording blood pressure from exercising subject
- in a hot/cold room
- exercised
- ate/smoked half hour before test
- changed posture w/i 5 minutes before test
Give a physiological explanation for the changes in systolic and diastolic blood pressure which you theoretically would expect to observe for your subject on the bicycle ergometer as exercise intensity increased from a low level to a higher level.
SBP increases as it delievers more oxygen to muscles but DPB oes not change too much because the blood vessels are dilated to help heat escape
Procedures which use submaximum exercise heart rates to predict VO2 max. are based on a number of assumptions. Describe three of these assumptions.
1) similar max HR for all subjects - standard of ~10 bpm from the average max HR for people of same age group
- max HR declines with age so age correction factor must be used
2) day to day variation in HR - even under standardized conditions (environmental temperature, time of day, diet, drugs, etc) variation is ~5 bpm at the same work rate
3) VO2 is predicted from work rate, fixed mechanical efficiency is assumed.
- mechanical efficiency may vary by 6% on a bicycle ergometer.
How would the predicted VO2 max. of a 40 year old subject be affected if the age correction factor was not used?
VO2 max decreases with age, so w/o it, it would appear as the 40 y/o had a very bad VO2 max when in reality, it is adequate for his/her age
Do you think that the Astrand bicycle ergometer test for predicting VO2 max. is a “well designed” physical fitness test?
no, most people not used to cycling
- better to use treadmill as walking more common
Fit individual has a heart rate of 122 bpm at power output of 900 kpm/min., while unfit subject has a heart rate of 164 bpm at same power output. Is cardiac output 1/3 higher in the untrained subject (assuming that the two men are the same height and weight)?
- fit individual will have a lower HR than unfit individual
- cardiac output will stay the same
Astrand Test: if measured heart rate 20-30 seconds afterwards rather than during exercise, then used the same tables to predict the subject’s VO2 max., what effect would this have on the estimation of the subject’s aerobic fitness level?
- HR would have time to decrease
- implies subject’s aerobic fitness is better
3 characteristics of a scholarly article
- peer reviewed
- sources
- written by scholar
Peer-reviewed journals
journal that has been reviewed by scholar’s peers (experts in certain field)
Serials
any publication issued in successive parts which are intended to be continued indefinitely
Research articles
reports the results of original research and is peer-reviewed
