RESPIRATION

RESPIRATION

TYPES OF RESPIRATION

There are 2 types of respiration:

•Aerobic respiration

•Anaerobic respiration

WHAT IS RESPIRATION?

•Respiration is a chemical reaction that takes place in the mitochondria of all cells.

•This chemical reaction releases energy in the form of a molecule called ATP

Organisms need energy:

•To power the chemical reactions needed to keep us alive, e.g. building large molecules.

•For movement (both within the organism and contraction of muscles)

•For keeping warm.

ORGANISMS ALSO NEED ENERGY FOR:

•Cell division

•To maintain a constant environment in our bodies

•For active transport

•To send nerve impulses

AEROBIC RESPIRATION

•When respiration uses oxygen it is called AEROBIC RESPIRATION.

•It is an exothermic reaction which means that it gives out heat.

•Any energy that is not used to create ATP (energy store) is released as heat

•Remember that any living organism has to carry out respiration therefore animals, plants and microorganisms all carry out respiration.

AEROBIC RESPIRATION REACTION

Glucose   +   Oxygen   à   Carbon dioxide +  Water + ATP

C6H12O6   +   6O2   à   6CO2        +   6H2O   + ATP

This reaction actually summarises a series of several reactions that take place in the cytoplasm of cells and mitochondria within cells.

One molecule of glucose can produce up to 38 ATP’s

https://www.youtube.com/watch?v=Xp0o19gWX7E Click on this to know more about respiration process.

RESPIRATION WITHOUT OXYGEN

•Respiration without oxygen is called ANAEROBIC RESPIRATION.

A good example of where anaerobic respiration happens is in:

•Fermentation (brewing)

•Active muscles e.g. sprinting/weight lifting

•Waterlogged plants (plants growing under water)

https://www.youtube.com/watch?v=6-D1oes63_U Anaerobic respiration fermentation

HOW DOES EXERCISE AFFECT RESPIRATION 

•Exercising increases the activity of muscles.

•These muscles will need more energy in order to contract faster.

•Therefore respiration must happen faster.

•This means that more oxygen and glucose needs to be delivered to the respiring cells.

•As a result breathing rate increases so that more oxygen diffuses into the blood.

•Heart rate increases so that more oxygen and glucose is delivered to the respiring cells.

ANAEROBIC RESPIRATION IN FERMENTATION 

ANAEROBIC RESPIRATION

•Yeast is a fungi that uses the sugar in the beer starting mixture for respiration so that they can grow (multiply).

•After a few hours there are so many yeast cells that the oxygen runs out and anaerobic respiration starts.

•When microorganisms respire anaerobically it is called FERMENTATION.

•Anaerobic respiration happens in the CYTOPLASM of cells.

ANAEROBIC RESPIRATION REACTION

Glucose à Ethanol + Carbon Dioxide (+ ATP)     PLANTS

Glucose à Lactic Acid + ATP            ANIMALS (HUMANS)

•Anaerobic respiration is less efficient than aerobic respiration and so does not make as much ATP.

•Each molecule of glucose produces about 2 ATP’s.

•The 2 ATP’s provide enough energy to enable the cells to survive