Aerobic respiration

Give the function of respiration, and write the word equation for aerobic respiration.
Identify the location of aerobic respiration within cells (mitochondria).
Describe how the body obtains and transports the necessary reactants (glucose and oxygen) to cells and removes the waste product (carbon dioxide).

Your body needs energy for every activity it performs—from movement and growth to keeping warm, even while you’re asleep.
This energy comes from the food you eat.
Inside your cells, glucose from food reacts with oxygen in a process called aerobic respiration.
This reaction releases energy that powers cellular functions, producing carbon dioxide and water as waste products.
The word equation for aerobic respiration is:

glucose + oxygen → carbon dioxide + water + energy

Respiration takes place in mitochondria, which are structures inside cells.
Nearly all cells have mitochondria, but those with high energy demands, such as muscle cells, contain many more to provide the energy needed for their functions.

Glucose is a carbohydrate obtained from food.
During digestion, food breaks down into smaller molecules, including glucose.
This glucose is absorbed through the walls of the small intestine and enters the bloodstream.
In the blood, glucose dissolves in plasma, the liquid component, which carries it to cells throughout the body.
From there, glucose diffuses into cells to be used in respiration.

When you inhale, oxygen fills the alveoli (air sacs) in your lungs.
Oxygen then diffuses into the bloodstream, where it binds to haemoglobin, a protein in red blood cells.
These cells transport oxygen throughout the body, delivering it to the cells that need it.
Once there, oxygen diffuses into the cells to be used in respiration.

Carbon dioxide is a waste product of respiration, and if it accumulated in the body, it would be harmful.
Carbon dioxide diffuses out of cells and into the blood plasma, which transports it to the lungs.
In the lungs, carbon dioxide diffuses into the alveoli and is then expelled from the body when you exhale.

Aerobic respiration: The process that takes place in cells using oxygen to release energy from glucose.
Reactants: The substances that go into a chemical reaction.
Products: The substances that are produced by a chemical reaction.
Glucose: A simple sugar molecule from food that is a key reactant in respiration.
Oxygen: A gas required for aerobic respiration, taken in through breathing.
Carbon dioxide: A waste product of aerobic respiration, removed from the body during exhalation.
Energy: Released during respiration and used by the body for all activities.
Mitochondria: Structures within cells where aerobic respiration occurs.
Haemoglobin: A protein in red blood cells that binds to and transports oxygen.

Compare aerobic respiration with anaerobic respiration (which happens without oxygen), highlighting the differences in the process, products, and amount of energy released.
Investigate how medical conditions that affect the transport of glucose (like diabetes) or oxygen (like anaemia) can impact the process of aerobic respiration in the body.