KEY CONCEPT All cells need chemical energy.

KEY CONCEPT All cells need chemical energy.

Photosynthesis & Cellular Respiration The “Big Picture” Light is sent to leaves of plants

(In Autotrophs only) Process of Photosynthesis Chlorophyll in a plant’s chloroplast absorbs the light energy and converts it into glucose, a carbohydrate. (In ALL cells) Process of Cellular Respiration Mitochondria break down the glucose to form ATP which is a stored and useable form of energy

(In all cells) ATP Cycle Photosynthesis Cellular Respiration The chemical energy used for most cell processes is supplied by ATP molecules.

Adenosine (adenine + ribose) Phosphate groups tri=3 Adenosine (adenine + ribose) Phosphate groups di=2 ATP Molecules

ATP Cycle The ATP cycle is like a rechargeable battery. Breaking off a ~P uses energy. Adding a ~P adds energy. A P ~ P ~P High energy bonds A P ~ P (ADP) A P (AMP) A P ~ P ~P (ATP)

phosphate removed ATP Cycle (continued) • Energy is released when a phosphate is removed • Energy is added when a phosphate is added

Organisms break down organic molecules to make ATP. • Lipids store the most energy. • Carbohydrates are the molecules most commonly broken down to make ATP. • up to 36 ATP from one glucose molecule • 80 percent of the energy in your body • about 146 ATP from a fat • Proteins are least likely to be broken down to make ATP. • amino acids not usually needed for energy • about the same amount of energy as a carbohydrate

Comparison of Energy from Organic Compounds

KEY CONCEPT All cells need chemical energy.