GAS EXCHANGE IN HUMANS

Question 1

Why do mammals need a large amount of 02 absorbed and C02 removed

Answer 1

1) they are large organisms

2) maintain a high temperature, so have high metabolic and respiratory rates

Question 2

What organ do mammals have to exchange gas

Answer 2

lungs

Question 3

Why are the lungs located inside the body

Answer 3

1) air is not dense enough to support and protect them

2) the body would lose a huge amount of water and dry out

Question 4

What are the lungs supported by

Answer 4

ribcage

Question 5

How are the ribs moved

Answer 5

intercostal muscles between them

Question 6

What are the main parts of the human gas exchange system

Answer 6

1) lungs
2) trachea
3) bronchi
4) bronchioles
5) alveoli

Question 7

What are the lungs

Answer 7

pair of lobed structures made up of highly branched tubes (bronchioles) that end in air sacs called alveoli

Question 8

What is the trachea

Answer 8

flexible airway

Question 9

What is the trachea supported by

Answer 9

rings of cartlidge

Question 10

Why does the trachea need to be supported

Answer 10

stops it collapsing as the air pressure drops when they breathe in

Question 11

What are the trachea walls made up of

Answer 11

muscle lined with ciliated epithelium and goblet cells

Question 12

What are the bronchi

Answer 12

2 divisions of the trachea each leading to the lungs

Question 13

What do the bronchi produce and why

Answer 13

mucus, to trap dirt particles

Question 14

What feature do bronchi have and why

Answer 14

cilia, to move dirt laden mucus towards the throught

Question 15

What is the larger part bronchi supported by

Answer 15

cartilage

Question 16

What are the bronchioles

Answer 16

series of divisions in bronchi

Question 17

What are bronchiole walls made up of and lined with and why

Answer 17

muscle, lined with epithelial cells, allows them to contrict so they can control the flow of air in and out of alveoli

Question 18

What are the alveoli

Answer 18

minute air-sacs that have membranes which are gas exchange surfaces

Question 19

What is the diameter of the alveoli

Answer 19

100um-300um

Question 20

What are between alveoli

Answer 20

collagen and elastic fibres

Question 21

What are the alveoli lined with

Answer 21

eputhelium

Question 22

What do the elastic fibres between alveoli allow them to do

Answer 22

stretch as they fill with air when breathing in, then spring back to expel the C02 rich air when breathing out

Question 23

What path does air take as it is breathed in

Answer 23

trachea, bronchi, bronchioles, alveoli

Question 24

How are alveoli adapted for gas exchange

Answer 24

1) thin exchange surface - alveolar epithelium only one cell thick
2) large surface area (lots of alveoli)