HUB2021S – Practical Exam Notes
Cardiovascular system
Calculate the heart rate:
- Count the number of peaks over the time period given; time is in seconds, convert to
minutes
- 46 beats per minute
A frog heart was connected to a force transducer and perfused:
,Direct stimulation of the heart:
A wave of atrial and ventricular
systole is depicted. Stimulation
occurred between atrial systole-
diastole and ventricular systole.
Ventricular systole is observed,
followed by an extra systole.
Because of this, a
compensatory pause followed
which is a long pause after an
abnormal heat. The heat then
returns backs to sinus rhythm.
Stimulation occurred during
ventricular diastole.
Ringer’s solution at different temperatures:
Room temperature (23°C)
Higher temperature = greater number of beats
per minutes
, Lower temperature = lower number of beats per
minute
Baseline measurements were made which is labelled as the “normal” phase → a chemical
was added at point 1→ the heart was flushed which is shown by the second “normal phase”
→ a second chemical was added at point 2
Point 1 –
- Mimics the sympathetic nervous pathway of the autonomic nervous system
- It caused an increase in the heart rate and an increase force production
Point 2 –
- Mimics the parasympathetic nervous pathway of the autonomic nervous system
- It caused a decrease in the heart rate and a decrease in force production
Cardiac physiology:
- The slow Calcium channels can be found in the cardiac muscle action potentials
- The slow Calcium channels prevent the cardiac muscle cells from entering tetanus
- The slow Calcium channels lengthen the cardiac muscle’s absolute refractory period
Cardiovascular system
Calculate the heart rate:
- Count the number of peaks over the time period given; time is in seconds, convert to
minutes
- 46 beats per minute
A frog heart was connected to a force transducer and perfused:
,Direct stimulation of the heart:
A wave of atrial and ventricular
systole is depicted. Stimulation
occurred between atrial systole-
diastole and ventricular systole.
Ventricular systole is observed,
followed by an extra systole.
Because of this, a
compensatory pause followed
which is a long pause after an
abnormal heat. The heat then
returns backs to sinus rhythm.
Stimulation occurred during
ventricular diastole.
Ringer’s solution at different temperatures:
Room temperature (23°C)
Higher temperature = greater number of beats
per minutes
, Lower temperature = lower number of beats per
minute
Baseline measurements were made which is labelled as the “normal” phase → a chemical
was added at point 1→ the heart was flushed which is shown by the second “normal phase”
→ a second chemical was added at point 2
Point 1 –
- Mimics the sympathetic nervous pathway of the autonomic nervous system
- It caused an increase in the heart rate and an increase force production
Point 2 –
- Mimics the parasympathetic nervous pathway of the autonomic nervous system
- It caused a decrease in the heart rate and a decrease in force production
Cardiac physiology:
- The slow Calcium channels can be found in the cardiac muscle action potentials
- The slow Calcium channels prevent the cardiac muscle cells from entering tetanus
- The slow Calcium channels lengthen the cardiac muscle’s absolute refractory period
