Cell EnergyBy: Amber Tharpe

ATP

• Adenosine triphosphate

• High energy molecule that stores and releases energy for cell processes when needed

ATP• Energy “currency” for the cell• Get it by breaking down food

–Mostly carbohydrates (glucose)

• When a phosphate is removed from ATP and added to another molecule

• Turns ATP to ADP• Releases energy• ATP ↔ ADP + P + energy

Uses of Energy

• Build cell parts• To maintain homeostasis• Movement• Active transport across cell membrane

Autotroph HeterotrophMake own food through photosynthesis

Eat other organisms- plants and/or animals

plants animals

The Sun is the Main Source of Energy

•All organisms get their energy either directly, or indirectly from the sun

Photosynthesis

•Process that plants use to capture energy from sunlight to store as sugar

• Chlorophyll

–Molecule in chloroplasts that absorb energy from sunlight

–Make plants appear green

• Chloroplast

–Membrane bound organelle where photosynthesis occurs

• Thylakoid

–Membrane containing chlorophyll

• Stroma

–Fluid inside chloroplast

Light Dependent Reactions

• Takes place in the thylakoid• Requires light• Chlorophyll captures energy

from the sun• Water molecules are split• Oxygen is given off

Light Independent Reactions

• Aka Calvin cycle or carbon fixation

• Occurs in the stroma• Does not require light• Carbon dioxide is used to make sugar (glucose)

Photosynthesis

•Total Reaction

6CO2 + 6H2O → C6H12O6 + 6O2

Cellular Respiration• Reverse reaction of photosynthesis• Releases energy from carbon-

based molecules to make ATP• Aerobic

–requires oxygen• Occurs in the mitochondria

Glycolysis• 1st stage of cellular respiration• Occurs in the cytoplasm• Anaerobic

–Does not require oxygen• Splits glucose into 2 pyruvates

• Makes 2 ATP

Krebs Cycle• Occurs in the matrix of the

mitochondria

• Pyruvate is broken down further

• Carbon dioxide is released

• 2 ATP are made

Electron Transport Chain (ETC)

• Series of proteins embedded in the cristae that make energy

• Electrons make ATP as they go through the proteins

• Oxygen is consumed

• Water is given off as waste

• Lots of ATP are made

Cellular Respiration

• Total Reaction

C6H12O6 + 6O2 → 6CO2 + 6H2O

• 36 ATP are produced

Fermentation• Anaerobic breakdown of sugar• Still goes through glycolysis• Produces carbon dioxide and

alcohol• 2 types

–Alcoholic–Lactic acid

Fermentation• Less efficient than cellular respiration

• continues glycolysis

• Makes only 2 ATP

Uses of Fermentation

Alcoholic

• Brewing

• Baking

• Carbonating

Lactic Acid

• Sore muscles

• Souring milk