Cardio-respiratory Sytem

Question 1

Structure of the respiratory system

Answer 1

See diagram in GC

Question 2

Function of the respiratory system

Answer 2

To supply body with oxygen and remove CO2.
Air enters your body and goes into your lungs.
In the lungs there are air sacs called alveoli.
They are surrounded by blood vessels called capillaries.
Oxygen is transported from the alveoli into the blood stream, then circulated to cells through the body.

Question 3

Physiology of respiratory system
(Inspiration)

Answer 3

Inspiration (air in):
-Diaphragm: contracts becomes flatter, lungs are pulled downwards.

-External intercostal muscles: These muscle contract, so ribs move up and out, allowing thoracic cavity to increase volume.

-Air pressure: The lungs increase volume, so there’s lower pressure within the lung than in the atmosphere. Therefore air is drawn in.

Question 4

Physiology of respiratory system
(Expiration)

Answer 4

-Diaphragm: Relaxes, moves upwards and returns to concave shape.

-External intercostal muscles: Relax, so ribs move downwards and inwards, reducing thoracic cavity volume.

-Air pressure: Lung volume decreases so pressure in the lung is higher than pressure of atmospheric air, so air moves out.

Question 5

Gas exchange

Answer 5

Is the delivery of oxygen from the lungs to the bloodstream. And the elimination of CO2 from the bloodstream to the lungs.

Question 6

Gas exchange process

Answer 6

It occurs in capillaries, that lie in the walls of the alveoli.
There’s a high conc of oxygen in alveoli and low in blood. So, oxygen diffuses from alveoli to blood.
And a high conc of CO2 in blood and low in alveoli. So, CO2 diffuses from blood to alveoli.

Question 7

Diffusion

Answer 7

Is the movement of a gas from an area of high conc, to an area of low conc.
Gas exchange occurs by diffusion

Question 8

Pressure gradient

Answer 8

The relative differences between the pressure within two adjacent areas.

Question 9

Diffusion gradient

Answer 9

Is a situation where the concentration of molecules of a particular substance (say oxygen for example) is greater on one side of a space than on the other side of the same space.

Question 10

What is a spirometer?

Answer 10

Is used to measure and record volumes of inspired an expired air.

See diagram in gc

Question 11

Spirogram

Answer 11

Is the graph produced by a spirometer.

Lines moving upwards on a spirometer trace show inhalation, while lines going down show exhalation

Question 12

How do lung volumes vary?

Answer 12

-Age
-Gender
-Body size
-Stature

Question 13

Breathing frequency

Answer 13

-Number of breaths per min
-Average resting value: 12 breaths per min
-The fitter the individual the lower breathing frequency.

Question 14

Tidal volume

Answer 14

-The volume of air displaced from the lungs during steady-state inspiration.
-Average resting value: 500ml
-The higher the tidal volume, the more CO2 is expelled from the lungs to breath.

Question 15

Minute ventilation

Answer 15

-Breathing frequency x tidal volume = MV
-The volume of air inspired or expired per min.
-Average resting value: 6.0 l/min
-Having a good MV aids to oxygen transport.

Question 16

Effects of exercise on respiratory system

Answer 16

-Respiratory muscles get fitter and stronger
-increase in lung volumes and capacity to breathe air.
-Improved utilisation of the alveoli, so increase gaseous change.
-Smaller oxygen debt

Question 17

What is an adaptation?

Answer 17

Take longer to occur, and are more permanent – at least until the environment changes

Question 18

Long term exercise - Adaptation

Answer 18

-Respiratory muscular system – diaphragm / intercoastal muscles – fitter and stronger

-submaximal workloads VO2 will be less because of greater efficiency of oxygen uptake

-Increase in oxygen diffusion rate.

-Increased number of alveoli’s.

-Capillarisation results in an increase of capillaries wrapped around the alveoli.