The Cell in Action Cell Energy Photosynthesis Cellular Respiration Fermentation

Cells Need Energy Cells of all organisms need energy to –Carry chemical activities of the cell –Reproduce –Grow –Live Where does this energy come from?

What Is Photosynthesis? Photosynthesis is the process by which a cell captures the energy in sunlight and uses it to make food. Photo = light & synthesis = put together Photosynthesis occurs inside chloroplast in the cells of plants and algae. Where in plants are cells with many chloroplasts found? Chloroplasts are green organelles inside plant cells.

Plant Cell Chloroplast Mitochondria

Chloroplast Traps the Sun’s Energy This energy-capturing process occurs in the leaves, and other green parts of the plant that contain chloroplast. This energy is then transferred to chlorophyll, a green pigment inside chloroplast. Chlorophyll gives plants their green color.

Photosynthesis

The energy captured by chloroplast drives the second stage of photosynthesis. At this stage, plants use: –Carbon dioxide CO 2 (a gas in the air) –Water H 2 O (absorbed by roots from soil) –Sun’s energy Carbon dioxide CO 2 enters the plant through small openings on the leaves called stomata. Once in the leaves, water and carbon dioxide move to chloroplast.

The Photosynthesis Equation 6 CO H 2 O → → → → → → C 6 H 12 O O 2 Light Energy

Cellular Respiration Cellular respiration is the process of converting nutrients such as carbohydrates, proteins, and lipids into glucose. In both plants and animals, cellular respiration takes place in the mitochondria. In cellular respiration glucose and oxygen combine to produce energy in form of ATP, water, and carbon dioxide.

Photosynthesis & Cellular Respiration

Plants do both photosynthesis and respiration. This means that plants are the only organisms that can make their own food. Hence, they are called producers. Animals can only make energy by eating other organisms. So, they are called consumers.

Cellular Respiration Equation C 6 H 12 O O 2 → → → 6 CO H 2 O + ATP glucose + oxygen → → → carbon dioxide + water + energy