Photosynthesis and Respiration USE THIS FOR SLOT NOTES

Sources of Energy All cells need energy to carry out their functions, such as making proteins and transporting materials in and out of the cell. Many organisms need to eat food in order to gain this energy.

Sources of Energy Some organisms, such as plants, algae, and some bacteria,don't eat food. Instead, they use the energy in sunlight to make their own food.

Sources of Energy An organism that uses energy from the sun to make it's own food is called an AUTOTROPH. An organism that obtains energy by eating other organisms as it's food is called a HETEROTROPH.

Sources of Energy The process by which a cell captures energy in sunlight and uses it to make food is called Photosynthesis. Nearly all living things obtain their energy either directly or indirectly from the energy of sunlight captured during photosynthesis.

DO NOW Trace the energy in each ingredient in a ham and cheese sandwich all the way back to the sun.

Photosynthesis During photosynthesis plants use the energy from the sun to convert Carbon Dioxide and Water into Oxygen and Sugar.

Photosynthesis Photosynthesis happens in 2 stages 1. Capture the sun's energy. 2. Use the energy to make food.

Capturing the Sun's Energy step 1 The chloroplasts in plant cells are full of a green pigment called chlorophyll. This pigment absorbs and traps the sun's energy.

Using the Captured Energy to Make Food step 2 In order to make a sugar, the cell needs two raw materials Water (comes up the roots to the leaves) 2. CO2 (comes into the leaf through the stomata) In the chloroplast these materials undergo a complex series of chemical reactions which produce sugar and oxygen as products.

Photosynthesis

Cellular Respiration During cellular respiration cells take sugar and break it down, releasing the stored energy.

Cellular Respiration In order get energy from sugar, the cell needs two raw materials Sugar (comes from the food an organism eats) 2. Oxygen (comes from the air or water surrounding the organism) In the mitochondria these materials undergo a complex series of chemical reactions which produce Carbon Dioxide and water as products.

Cellular Respiration The first part of cellular respiration takes place in the cytoplasm. Here molecules of sugar are broken down and a small amount of energy is made. The second part of cellular respiration takes place in the mitochondria. Here oxygen is used to create a large amount of energy.

Cellular Respiration

FERMENTATION Fermentation is a way of providing energy for cells without using any oxygen. Some organisms, like yeast, use fermentation to make energy for their cells. This produces alcohol in the process so it is called alcoholic fermentation. In humans, when not enough oxygen is available, muscle cells use a process called lactic acid fermentation to provide energy for your cells.