Cardio-respiratory system Flashcards
Identify the 5 locations involved in the Pathway of Air (- Never Make Tracey Buy Little Blueberries After-all)
- Nose/ Mouth
- Trachea
- Bronchi
- Lungs
- Bronchioles
- Alveoli
Where does Gaseous Exchange take place?
Alveoli
What features of the alveoli assist Gaseous Exchange?
- Large surface area
- Moist, thin walls (one cell thick). Promoting quick diffusion
- Lots of capillaries
- Large blood supply
- Movement of gas from a low concentration to a high concentration (concentration gradient)
Name the 3 main blood vessels
- Veins
- Arteries
- Capillaries
Name the largest artery in the body and describe it’s function
Aorta - transports oxygenated blood away from the heart to the rest of the body
Where do we find valves? What are their function?
Veins - prevent the back flow of blood
Function of capillaries
- Deliver nutrients e.g glucose
- Remove waste products e.g carbon dioxide
Structure of capillaries
- Thin, one cell thick
- Narrow, only allows one red blood cell through at a time
- Connect arteries to veins
Structure of an artery
- Thick
- Very elastic
- Small arteries are called arterioles
Function of an artery
Carries oxygenated blood away from the heart at high pressure
Structure of veins
- Thin
- Non-elastic
- Contains pocket valves
(- Small veins are called venules)
Function of veins
- Carries blood at low pressure
- Carries blood towards the heart
- Carries deoxygenated blood
Redistribution of blood during exercise is called… ?
Vascular Shunt
Name the two mechanisms used to control the redistribution of blood
Vasoconstriction and Vasodilation
What is Vasodilation?
The expanding of the blood vessels to distribute the blood to the areas of the body that need it the most.
E.g. When running, the blood vessels that access the muscles in the legs expand to allow more oxygenated blood to reach the working muscles. Consequently, the muscles can work for a longer period of time.
What is Vasoconstriction?
The narrowing of the blood vessels to redistribute the oxygenated blood to the working muscles elsewhere in the body.
E.g. When running, the blood vessels in the arms will narrow to allow the oxygenated blood to be redistributed to the working muscles in the legs.
Name the 4 chambers of the heart and identify what type of blood they use
Right Atrium - Receives de-oxygenated blood
Right Ventricle - Contains de-oxygenated blood
Left Atrium - Receives oxygenated blood from the lungs
Left Ventricle - Contains oxygenated blood
Name the 4 main blood vessels in the heart
- Pulmonary Artery
- Aorta
- Vena Cava
- Pulmonary Vein
Function of the Pulmonary Artery
Carry deoxygenated blood from the heart to the lungs
Function of the Aorta
Carries oxygenated blood under high pressure from the heart to the body
Function of the Vena Cava
Returns deoxygenated blood to the heart
Function of the Pulmonary Vein
Returns oxygenated blood from the heart to the lungs in order to be pumped to the rest of the body
Name the 2 stages to a heart beat
- Diastole
2. Systole
What happens during Diastole?
The heart fills with blood; it is relaxing
What happens during Systole?
The heart is empties; it is contracting
Mechanics of breathing - Inspiration
- Intercostals contract - lifting the ribcage up and out (causing the chest to expand).
- Diaphragm contracts - pulls the floor of the rib cage down and flattens it
- Lungs increase in size (chest is expanding).
- Pressure inside of the lungs falls as they expand. (Because the higher pressure is outside of the lungs, air is sucked in via the nose and mouth).
Mechanics of breathing - Expiration
- Intercostals relax - ribs move down and in (chest decreases in size).
- Diaphragm relaxes (pushed back into the dome shape).
- Lungs decrease in size - diaphragm and intercostals are ‘squeezing’ the air out (chest decreases in size).
- Pressure inside of the lungs increases. (Because the pressure outside of the lungs is now lower, air is forces out via the nose and mouth).
Define Tidal Volume
The normal volume of air inspired and expired per breath.
What happens to tidal volume during exercise?
It increases
Define Inspiratory Reserve Volume
The volume that can be forcibly inspired during normal breathing
What happens to Inspiratory Reserve Volume during exercise?
It decreases
Define Expiratory Reserve Volume
The volume of air that can be forcibly expired after a normal breath.
Define Residual Volume
The volume of air left in the lungs after maximum expiration
What happens to Residual Volume during exercise?
It stays the same
What happens to Expiratory Reserve Volume during exercise?
It decreases (slightly).
What muscles allow the lungs to expand more during exercise (inspiration)
Pectorals and Sternocleidomastoid (neck)
