Energy Flow in Living Things CHEMICAL ENERGY What

Energy Flow in Living Things

CHEMICAL ENERGY ● What do organisms use energy for? o. Cell repair o. Growth o. Reproduction o. Movement o. Active Transport

Main Ideas The chemical energy used for most cellular processes is carried by ATP (adenosine triphosphate). ● Organisms break down carbon-based molecules to produce ATP. ●

ATP Adenine Ribose ATP = nitrogenous base(adenine), sugar (ribose), 3 phosphate groups

● Adenosine Triphosphate ● Transfers energy to cell processes. ATP ADP ● Adenosine Diphosphate ● Lower energy molecule that can be converted into ATP.

ATP-ADP Cycle “recharging a battery” - http: //www. biologyinmotion. com/atp/index. html

Breaking Down Carbon. Based Molecules Foods that you eat do not contain ATP, but after you digest the food it is broken down into smaller molecules which the body uses ● o. Carbohydrates = 4 calories of energy per mg o. Lipids = 9 calories of energy per mg o. Proteins = 4 calories of energy per mg ● Fats store 80% of the energy in your body.

Typical Energy Flow ● Most organisms rely directly or indirectly on sunlight and photosynthesis as their source of chemical energy. o Some do not…

Chemosynthesis ● Chemosynthesis: use chemical energy instead of light energy to make energystoring carbonbased molecules. o Ex: Bacteria near hydrothermal vents

A Look Ahead… Photosynthesis – process that captures energy from sunlight to make sugars that store chemical energy ● Cellular Respiration – releases chemical energy from sugars and other carbon-based molecules to make ATP when oxygen is present ●

Key Organelles