Cardiovascular System Flashcards
What are primary roles of the cardiovascular system?
- Transport oxygen from lungs to tissues
- Transport carbon dioxide from tissues to lungs
- Transport nutrients from digestive system to body
- Transport waste to excretion
What does the atria do?
Receive blood from peripheral organs and pumps blood into ventricles
What does the Right ventricle do?
Pumps blood to the lungs
What does the Left ventricle do?
Pumps blood through entire body
Diastole
Ventricles relaxing and filling with blood
Systole
Ventricles contracting, push blood through
Arteries carry _______ blood EXCEPT for the ___________
- Oxygenated blood
- Pulmonary artery
Veins carry ______ blood EXCEPT for the ____________
- Deoxygenated blood
- Pulmonary vein
What is the heart structure?
Heart tissue blood supply
-Coronary arteries
-Coronary veins
Sinus node
The beating of the heart is governed by a automatic electrical impulse generated by the sinus node
Action potential in the heart?
An electrical charge generated by the sinus node. The action potential causes the muscle walls of the heart to contract
Purkinjie fibres
What distributes the action potential to the two ventricles
Heart rate = beats per minute (bpm
Average = ________ bpm
60 - 80 bpm
What is Tachycardia?
Persistent resting heart rate >100 bpm
What is Bradycardia?
Persistent resting heart rate <60 bpm
Stroke volume = ml/beat
________ ml/beat
60 - 80 ml/beat
Cardiac output: volume ejected 1/min
= heart rate (bpm) x stroke volume (ml/beat)
At 80 bpm x 60 ml/beat = 4.8 L
At 80 bpm x 80 ml/beat = 6.4 L
What is MaxHR?
Highest rate achieved with all-out effort
When does MaxHR begin to decrease?
Decreases about 1 beat/ yr after 15 yr
How to estimate MaxHR in adults?
MaxHR = 220 - age
What are the vessels of the circulatory system?
Arteries
Veins
Capillaries
What are the vessels of the arterial system?
Arteries
Arterioles
Capillaries
What are Arterioles?
Arteries that branch into smaller and smaller vessels
What are capillaries?
Arterioles that branch into even smaller vessels
Capillaries function
Exchange of oxygen and nutrients from blood to muscles and organs
Allow blood to pick up waste products and CO2 from metabolism
What do veins have that arteries don’t?
Valves that open as blood returns to the heart and close as blood flow away from the heart
Redistribution of blood
- Vasodilation
- Vasoconstriction
At rest:
____% of blood to liver and kidney
____% of blood to muscles
Heavy endurance training
____% blood to muscle
- 50%
- 15%
- 80%
What is blood pressure (mmHg)?
Pressure exerted on the vessels during systole (contraction of ventricles) and diastole (relaxation of ventricles)
Systolic pressure average?
120 mmHg
Diastolic pressure average?
80 mmHg
What does exercise do to heart rate?
Increases heart rate via proprioceptors. Signals to heart centre in medulla, which signals heart to increase rhythm
What does muscular activity increase?
Venous return
What does sustained exercise do?
- Creates more efficient heart (increased size of cavities and thickness of walls = cardiac hypertrophy)
- increased stroke volume
- allows heart rate to beat more slowly at rest (endurance athletes 40 -60 bpm)
Increases:
Red blood cells and capillaries
