Organisms are a composition of different types of cells that perform different types of functions- essential to keep them alive. like – nutrition /transport /excretion /reproduction AND to perform all of these processes the cells require.

1. A process in living organisms involving the
production of energy .
RESPIRATION

2. Pratyusha Ranjan Sahoo
and
Swechha kumari
RIE, NCERT, Bhubaneswar

3. Why do we NEED to respire ?
Organisms are a composition of different types of
cells that perform different types of functions-
essential to keep them alive.
like – nutrition /transport /excretion /reproduction
AND to perform all of these processes the cells
require. This energy is
acquired from
respiration

4. Food has stored energy –released during respiration.
all organisms respire – energy-from food.
• Air (breathe in ) – has oxygen
Air (breathe out) – carbon dioxide rich
• The air that we breathe – transported – all parts of the
body –to reach every cell
• Oxygen in the air –helps- breakdown of food .

5. • The process of breakdown of food in the cell with the
release of energy is called – Cellular respiration.
• Cellular respiration takes place in cells of all organisms .
• In this process
food=glucose
• The breakdown of glucose is possible in the presence
and absence of oxygen.

6. Aerobic respiration Anaerobic respiration
Breakdown of
food/glucose with the
use of oxygen
Breakdown of
food/glucose
without the use of
oxygen

7. • Organisms that survive in the absence of
oxygen are called anaerobes.
eg:- Yeast – single celled organisms - respire
anaerobically - produce alcohol - therefore are used to make
wine and beer
• why anaerobic mode of respiration when one
can utilize oxygen to produce energy?
answer:- availability of oxygen

8. Anaerobic respiration in human beings
our muscle cells – can respire anaerobically – but only for
a short period of time – when there is shortage in
oxygen supply to the muscles .
muscular activities- heavy exercise, fast running, cycling ,
walking for a many hours, weight lifting – high demand
of energy .
Oxygen supply is limited in the muscles (or any part of
body), so to fulfill the sudden requirement of energy ,
the muscle cells do anaerobic respiration.
.

9. • Partial breakdown of glucose produces lactic
acid which gets deposited in the muscle cells.
• The accumulation of lactic acid in the muscles
causes muscle cramps.

10. Aerobic respiration in human beings
• Aerobic respiration in humans occurs by the
process of breathing .
• Breathing is essential to survive . If not -
30-180sec–looseconsciousness
1min-braincellsbegintodie
10Min–coma
Breathing means taking in air containing
oxygen and giving out air rich in carbon
dioxide.

11. inhalation
The taking in oxygen rich air into the body.
Exhalation
The giving out of air rich in carbon dioxide.
It is a continuous process that goes on all the time and throughout the life of an
organism.
One breathe = one inhalation +one exhalation
ACTIVITY:- lets count the no. of times we breathe in a minute .
The no. of times a person breathes in a minute is termed as the breathing rate .

12. Summary
Respiration- A process in living organisms involving the production of
energy .
Aerobic respiration - Breakdown of food/glucose with the use of
oxygen.
Anaerobic respiration- Breakdown of food/glucose without the use of
oxygen.
Breathing- it means taking in air containing oxygen and giving out air
rich in carbon dioxide
Inhalation -The taking in oxygen rich air into the body.
Exhalation- The giving out of air rich in carbon dioxide.
Breathing rate- The no. of times a person breathes in a minute is
termed as the breathing rate .