Introduction to Respiration

Biology

What do we need energy for?

• You have 2 min as a group to act out different activities your body requires energy for!

How is digested food used by the body?

Glucose, from digested carbohydrates, is an important substance that contains stored chemical energy. This is released when it reacts with oxygen in cells.

The energy is used in many ways, such as for:

The body needs a constant supply of energy which comes from digested food.

enabling muscles to contract

keeping warm in mammals and birds

building new molecules, cells and tissues.

What is respiration?Respiration is the process that the body uses to release energy from digested food (glucose).

This type of respiration is called aerobic respiration because energy is released in the presence of oxygen.

How do the glucose and oxygen needed for aerobic respiration get to the all the body’s cells?

oxygencarbondioxideglucose + + water ( energy)+

from the digestive system

from the respiratory

system

waste product (exhaled)

waste product (exhaled)

What do you notice about these two equations?

Plants respire too!glucose + oxygen Water + carbon dioxide (+ energy)

Reactants Products

• Aerobic respiration (uses oxygen)• Happens all the time• Overall plants produce more oxygen by photosynthesis than they use by

respiration

YouTube - Plant Physiology: Respiration (Britannica.com)

How can we prove respiration is taking place?

• Limewater-tests for the presence of carbon dioxide-how does it change when it is present?

• Cobalt chloride paper-tests for the presence of water-how does it change when water is present?

Why do we breathe more when we exercise?

• Each group needs to come up with a theory linking it back to the equation for aerobic respiration

• Carry out an experiment to test your theory-I’ll provide this!