Unit 2.1 Flashcards
State composition of blood
Plasma (55%)
-Yellowy liquid containing mainly water (91%).
-Soluble blood proteins (7%).
-Hormones.
-Electrolytes (salts).
-Nutrients.
Cellular component (<1%)
-White blood cells and
-Platelets
Red Blood Cells (45%)
Systolic Blood Pressure
This is the force exerted on arterial walls when the ventricles are contracting.
Diastolic Blood Pressure
This is the force exerted on arterial walls when the ventricles are relaxing.
Talk about systolic and aerobic exercise and weight training impact on diastolic and systolic BP
Aerobic = Raises SBP, only a small rise in DBP.
Weight Training = Large Raises of SBP, large raise of DBP.
Larger muscle groups = larger change.
Talk about systolic and dynamic and static exercise impact on diastolic and systolic BP
Dynamic Exercise = Slight raise in SBP, no raise in DBP
Static Exercise = Large raise in SBP, small raise in DBP
Talk about heart structure
Heart - an involuntary muscle with
striated muscle fibers (myocardium).
Atria - (left & right) receiving blood
from the body. Have thin walls bc they
only have to pump to the ventricles
Ventricles - (left & right) they are thick
as they propel blood from the heart to
body
Valves - prevent backflow by shutting
when the heart relaxes
1. Atrioventricular valves (tricuspid &
bicuspid/mitral) 2. Pulmonary and
Aortic Semilunar Valve
Talk about intrisinc regulation of heart
- Starts in the right atrium
- A cardiac impulse is initiated from the sino-atrial
(SA) node (pacemaker) - The impulse causes the atria to contract
- Cardiac impulse reaches and activates the
atrioventricular (AV) node - This passes the impulse down Bundle of His (in
the septum of the heart) - Bundle of his splits left and right, up around the
heart (Purkinje fibers) - The impulse is spread around the walls of ventricles causing them to contract
- Ventricles relax and the cycle starts again
Talk about extrinsic regulation of heart
Parasympathetic nervous system
Its general function is to control homeostasis and the body’s rest-and-digest response.
Function:
Control the body’s response while at rest.
Activates response of:
Rest and digest
Originates in:
Sacral region of spinal cord
Cardiovascular System (heart rate):
Decreases heart rate
Sympathetic nervous system
Function:
Control the body’s response during perceived threat.
Originates in:
Thoracic and lumbar regions of spinal cord
Activates response of:
Fight-or-flight
Cardiovascular System (heart rate):
Increases contraction, heart rate
Outline the relationship between pulmonary and systemic circulation
Pulmonary Circulation - carries deoxygenated blood away from the heart to the lungs and returns oxygenated blood back to the heart
Systemic Circulation - carries oxygenated blood away from the heart to the body and returns deoxygenated blood back to the heart
Describe the relationship between heart rate, cardiac output and stroke volume at rest and during exercise
When the body starts to exercise there is a higher demand of oxygen, causing heart rate,
stroke volume and cardiac output to increase
Cardiac output equation
Q = SV x HR
Heart Rate (HR)
the number of times the heart beats per minute (bpm)
Stroke Volume (SV)
- the amount of blood pumped by the left ventricle per beat (litres)
Cardiac Output (Q)
- the amount of blood pumped from the heart in one minute (liters)
Basal Heart Rate
when HR is reduced to a min (ex. sleeping)
Venous Return
the amount of blood returned to the right side of the heart
- Less blood returned meaning heart rate is increased
Analyse cardiac output, stroke volume and heart rate data for Males vs Females at
rest and during exercise
Heart Rate - lower in males than females (exept max)
Stroke Volume - higher in males (body size plays a role)
Cardiac Output - higher in males
Trained vs Untrained cardiac output, stroke volume and heart rate
Heart Rate - trained have a lower heart at rest and during maximal exercise
Stroke Volume - trained have a larger stroke volume at rest and during maximal exercise
Cardiac Output - same during rest and sub-maximal exercise, but trained have higher during
maximal exercise
Young vs Old Untrained cardiac output, stroke volume and heart rate
Heart Rate - higher in children than adults
Stroke Volume - lower in children than adults
Cardiac Output - smaller in children than adults
Cardiovascular drift
After a long period of steady state exercise, less blood returns to the heart. Loss of blood plasma through sweating and our body sending blood to the skin to lose heat is the cause of this.
There is literally less blood volume, which means stroke volume decreases.
To cope with the lower Stroke Volume, our heart rate increases to maintain Cardiac Output.
Arteries structure and functions
Carry high pressure blood
Thick wall lumen
Elastic walls to cope high pressure
Usually carry oxygenated blood (expect pulmonary artery)
Vein structure and functions
Carry low pressure blood
Valves to prevent backflow of blood to bring deoxygenated blood back to heart (expect pulmonary vein)
Wide lumen
Capillary structure and functions
Once cell thick
Allows diffusion of glucose and oxygen
Redistribution of blood in exercise and rest
During rest blood will move to organs (ex. digestion)
Approx 80% to organs and 20% to mucles
at rest blood more evenly distributed amongst organs
During exercise blood will move towards the muscles
more then 80% blood to muscles less then 20% to organs
Vasodilation to muscles, vasoconstriction at other organs
