Cellular respiration is the process by which organisms produce energy through the breakdown of glucose and oxygen. It takes place in the mitochondria of cells. The three main stages are glycolysis, the Krebs cycle, and oxidative phosphorylation. Glycolysis breaks down glucose, the Krebs cycle further breaks down these products, and oxidative phosphorylation uses the energy from these processes to produce ATP through electron transport chains. Cellular respiration requires oxygen and glucose and produces carbon dioxide, water, and energy in the form of ATP. It is essential for energy production in all living organisms.

1. CELLULAR RESPIRATION
(process of energy production)
SIPHESIHLE MASEMOLA
216053035
TST0B3: RE-PURPOSE

2. WHAT IS CELLULAR RESPIRATION?
 The process by which energy is produced using oxygen and food.
 The requirements of cellular respiration are oxygen and glucose,
 The byproducts are carbon dioxide and water.
 The chemical formula of cellular respiration is as follows;
C6H12O6 (glucose) + O2 = CO2 + H2O + ATP
And is the opposite of photosynthesis.

3. WHICH ORGANISMS CAN UNDERGO
CELLULAR RESPIRATION?
 All living organisms undergo cellular respiration
 Cellular respiration helps living organisms with metabolic processes
 Herbivores obtain their food through cellular respiration
 Carnivores and omnivores benefit from cellular respiration by means of metabolic reactions
 Cellular respiration is directly linked to photosynthesis.

4. WHERE DOES CELLULAR RESPIRATION
TAKE PLACE IN LIVING ORGANISMS?
Cellular respiration takes in both the animal and plant cells of living
organism.
It takes in an organelle called the mitochondria of the cell which is
responsible for providing the cell with energy.
The mitochondria has a double unit membrane which is the; outer
membrane (smooth oval) and the inner membrane (folded cristae)

5. THE STRUCTURE OF THE
MITOCHONDRIA

6. COENZYMES REQUIRED FOR CELLULAR
RESPIRATION
 NAD+ :
• A coenzyme that is a electron acceptor, accepts 2 electrons and 1 hydrogen ion to form
NADH.
• The opposite can happen with NADH giving off electrons and hydrogen ions to form NAD+
again.
 FAD:
 A coenzyme that is a electron acceptor, accepts 2 electrons and 2 hydrogen ions to form
FADH2.

7. STAGES OF CELLULAR RESPIRATION
 Cellular respiration is divided into 2 processes:
1. Aerobic respiration
 Requires oxygen to take place
 Glucose + oxygen = water + carbon dioxide + ATP
 Includes 3 phases; glycolysis, Krebs's cycle and oxidative phosphorylation
2. Anaerobic respiration
 Does not require oxygen to take place
 Products are alcohol and lactic acid
 Includes fermentation

8. GLYCOLYSIS
 Occurs in the cytoplasm of the cell
 Glucose is broken into 2x pyruvic acids
 Energy rich in H atoms are given to coenzyme NADH and move to the
mitochondria to used during oxidative phosphorylation.
 2ATP molecules are released.

9. GLYCOLYSIS

10. KREB’S CYCLE
o Occurs in the mitochondria
o Pyruvic acid from Glycolysis is broken down
into carbon dioxide and energy rich H atoms
which are picked up by NAD, to be used
during oxidative phosphorylation.
o Carbon dioxide will be transported in the
blood to the lungs and exhaled during
breathing.
o The cycle starts again.

11. OXIDATVE PHOSPHORYLATION
 Occurs in the mitochondria
 The energy from the energy rich NADH is
used to make ATP
 The H in the in the NAD combines with
oxygen to make water
 The water is either exhaled as water
vapour or is excreted by the kidneys as
part of urine.

12. FERMENTATION
 Fermentation is an anaerobic reaction of cellular respiration that does not
require oxygen to take place
 It therefore, a glycolysis reaction that happens during this phase.
 Fermentation has two products:
1. Alcoholic fermentation
2. Lactic acid fermentation

13. FERMENTATION

14. REFERENCE
• Jones, R. (2007) 4.4 Aerobic respiration. Available from Slideshare at https://www.slideshare.net/cgales/cellular-
respiration?next_slideshow=1
• McGinley, M. (2012) Cellular Respiration. Available from Slideshare at
https://www.slideshare.net/MarkMcGinley/cellular-respiration-11758578
• Serrano, C. (2015) Cellular Respiration. Available from Slideshare at https://www.slideshare.net/chrstnbby/cellular-
respiration-45943784
• BiologyIB. (2010) Cellular Respiration. Available from Slideshare at https://www.slideshare.net/BiologyIB/cellular-
respiration-powerpoint
• Skyujones. (2013) Aerobic Respiration. Available from Slideshare at https://www.slideshare.net/skyujones/aerobic-
respiration-16471478