1.2 Gas exchange and respiration (Cellular respiration)

• Biology
• Middelbare school
• havo, vwo
• Leerjaar 2

Learning objectives: 'what I am going to learn?'

I can .... 

• explain what air is.
• explain the difference between breathing, gas exchange and cellular respiration 
• explain the relation between photosynthesis and cellular respiration

New key terms:

inhalation - exhalation - lung ventilation - gas exchange - 

cellular respiration 

Air is a mixture of gasses 

breathing = lung ventilation = inhalation + exhalation

so your body takes 4% oxygen and gets rid of 3,96% of CO2 and a lot of water ... why? Read a again the introduction of par. 1.1.

so 21- 17 = 4% O2 is used in the body

so 4-0,04=3,96% CO2 is waste from the body

a lot of water is exhaled!

Why?

breathing (a.k.a. respiration) vs gas exchange vs cellular respiration

external : 

    outside the body

internal: 

-   inside your body -   in or in between         your cells 

breathing (a.k.a. respiration) vs gas exchange vs cellular respiration

1. breathing/respiration/lung ventilation: 

• inhalation & exhalation; moving air through the respiratory tract

2. gas exchange (par. 1.3) 

• exchange of gasses from alveoli (external)  to lung capillaries  (internal) and vice versa , or between capillary and body cell, by a process called diffusion

3. cellular respiration: 

• the process by which your cells make energy (and carbon dioxide and water vapour) from glucose, with the help of oxygen

combustion vs cellular respiration 

combustion:  fuel + oxygen -> carbon dioxide + water + energy 

fuel :  candle, paper, alcohol, gasoline, etc. 

energy: heat, light, locomotion

cellular respiration = combustion is body cells 

fuel : glucose

energy: heat, ATP 

why do organisms need cellular respiration? the energy is needed for  

- to move (muscle contractions) 

- to keep 37C body temperature 

- to grow or to repair or replace damaged cells 

cellular respiration:

glucose + 1 -> 2 + water vapour + E

1. 1=carbon dioxide 2= oxygen
2. 1= oxygen 2= carbon dioxide

When do your body cells respire the most?

1. when you run
2. when you've had your dinner
3. when you are asleep
4. when you just have woken up

when do your muscle cells respire the most?

1. playing basketball during PE hour
2. doing a practical during biology

You are shivering because the temperature in your room is 15C.
- how does your body react?

1. more cellular respiration
2. less cellular respiration

huiswerk

par. 1.2 

summarize What is air & cellular respiration

do exercise 1, 10 and 11