ventilation

Question 1

trachea

Answer 1

passage of air, cells lined with cillia and have rings of cartilage

Question 2

bronchi

Answer 2

initial branching of the trachea

Question 3

bronchioles

Answer 3

deliver air to and from the lungs

Question 4

alveoli

Answer 4

increases surface area of lungs + site of gas exchange

Question 5

capillary network

Answer 5

brings C02 to lungs and removes 02 - site of gas exchange

Question 6

pleural membrane

Answer 6

secretes pleural fluid to reduce friction when breathing

Question 7

intercostal muscles

Answer 7

contracts to move ribs up and out

Question 8

diaphragm

Answer 8

contracts and flattens

Question 9

ciliated epithelial cell

Answer 9

found in the lining of trachea, bronchi and bronchioles
secretes mucus from goblet cells and cillia and traps the mucus along with pathogens + harmful substances
- travels in waves, transporting the mucus out of the airways so that they can be removed

Question 10

what happens to intercostal muscles and diaphragm when contracting

Answer 10

IM gets shorter & D contracts

Question 11

explain inspiration/inhalation

Answer 11

1. external intercostal muscles contracts moving the ribs outwards and upwards
2. diaphragm also contracts causing it to flatten
3. volume of thoracic cavity increases
4. pressure of lungs decreases that of atmospheric pressure (lower compared to outside)
5. air moves into the lungs down a pressure gradient

Question 12

what type of process is inhalation/inspiration?

Answer 12

active

Question 13

explain exhalation/expiration

Answer 13

1. external intercostal muscles relaxes causing the ribcage to move inwards and downwards
2. diaphragm also relaxes causing it to return to its domed position
3. volume of thoracic cavity decreases
4. pressure in lungs increases above that of atmospheric pressure
5. air moves out of the lungs down pressure gradient

Question 14

tidal volume

Answer 14

amount of air that an individual breathes in and out at rest

Question 15

inspiratory reserve volume

Answer 15

volume of extra air that can be breathed out

Question 16

expiratory reserve volume

Answer 16

volume of EXTRA air that can be exhaled during a forceful breath out

Question 17

vital lung capacity

Answer 17

total amount of air after maximum exhalation

Question 18

total lung capacity

Answer 18

volume of air exhaled during a forceful breath out

Question 19

residual volume

Answer 19

volume of air that remains after a forceful expiration

Question 20

peak expiratory flow

Answer 20

volume of air expelled from the lungs in one quick exhalation

Question 21

what does peak expiratory flow indicate

Answer 21

whether airways are narrowed

Question 22

forced vital capacity

Answer 22

maximum air that is forcibly exhaled from the lungs after fully inhaling

Question 23

what is forced vital capacity used to diagnose

Answer 23

COPD and other respiratory related conditions

Question 24

why should peak flow score be repeated

Answer 24

to calculate an average of results & repeat 3x

Question 25

fick's law

Answer 25

law stating that diffusion is directly proportional to surface area and concentration but not the thickness of membrane

Question 26

using fick's law explain how the lungs are adapted for efficient gas exchange

Answer 26

- alveoli walls is thin + 1 cell thick so so short diffusion pathway between alveolar walls and capillary network - layer of water surrounding alveoli so moisture as gases can diffuse easily and efficiently + contains a surfactant which reduces surface tension preventing the alveolar walls from collapsing and sticking together - alveoli and capillaries have large total surface area squamous endothelial cells squashed cells to allow short diffusion pathway due to being thin good blood supply - maintains high concentration gradient for both gases

Question 27

how does oxygen enter the blood?

Answer 27

oxygen passes through the epithelial cell of the alveoli by diffusion 2. then diffuses into the endothelial cell of alveoli 3. combines with haemoglobin on red blood cells forming oxyhaemoglobin