BREATHING

Question 1

What is inspiration (inhalation) and when does it occur

Answer 1

air being forced into lungs, when the air ppressure of atmosphere is greater than air pressure inside the lungs

Question 2

What is expiration (exhalation) and when does it occur

Answer 2

air forced out of the lungs, when the air ppressure of atmosphere is less than air pressure inside the lungs

Question 3

How many sets of muscles cause inhalation/exhalation and what are they

Answer 3

3,

1) diaphram
2) internal intercostal muscles
3) external intercostal muscles

Question 4

What is the diaphram

Answer 4

sheet of muscle that seperates the thorax from the abdomen

Question 5

Where do the internal intercostal muscles

and external intercostal muscles lie

Answer 5

between the ribs

Question 6

What does the contraction of the internal intercostal muscles cause

Answer 6

exhalation

Question 7

What does the contraction of the external intercostal muscles cause

Answer 7

inhalation

Question 8

Is inhalation a passive or active process

Answer 8

active

Question 9

What are the processes of inhalation (5)

Answer 9

1) external intercostal muscles contract & internal relax
2) ribcage is pulled upwards and outwards so volume of thorax increases
3) diaphram contracts so flattens, increasing volume of thorax
4) volume increases, so pressure in lungs decreases
5) atmospheric pressure is greater than pulmonary pressure, so air is forced into lungs (pressure gradient)

Question 10

Is expiration a passive or active process

Answer 10

mainly passive

Question 11

What are the processes of exhalation (5)

Answer 11

1) internal intercostal muscles contract & external relax
2) ribcage moves downwards and inwards and so volume of thorax decreases
3) diaphram muscles relax and so pushed up by the cintents of abdomen that were compressed during inspiration = volume of thorax decreases
4) decreased thorax volume increases pressure in the lungs
5) pulmonary pressure is greater than atmospheric pressure, so air is forced out (pressure gradient)

Question 12

What happens during forced expiration

Answer 12

intercostal muscles movement is antagonistic (opposing)as the external relax whilst internal contract

Question 13

What is pulmonary ventilation rate

Answer 13

the total volume of air moved into the lungs during one minute

Question 14

How do you calculate the pulmonary rate

Answer 14

tidal volume (dm3) X breathing rate (min-1)

Question 15

What is the pulmonary rate measured in

Answer 15

dm3min-1

Question 16

What does the pulmonary ventilation rate tell us

Answer 16

the amount of air taken in and out of the lungs in a given time