Energy in a Cell

All Cells Need Energy  Cells need energy to: –Make new molecules. –Build membranes and organelles. –Move molecules in and out of the cell. –Move.

Autotrophs (producers)  Organisms that make their own food  Use light energy from the sun to make food Example: PLANTS

Heterotrophs (consumers)  Organisms that get energy from the foods they eat Example: ANIMALS

NOT a flashcard.

Where Does A Cell Get Energy?  Food is broken down to a form the cell can use.  Extra energy is stored in an ATP molecule.

ATP  Adenosine triphosphate is a molecule made up of –adenine –ribose –3 phosphate groups. Adenine Ribose (ENERGY STORED HERE!)

ADP  Adenosine diphosphate. Made up of –adenine –ribose –2 phosphate groups. Adenine Ribose

How Does ATP Work?  Energy is stored in the bond between the second and third phosphate group.  When the bond is broken, energy is released and ADP is formed. Adenine Ribose

Storing Energy  Energy is stored by the cell when 1 phosphate is added to the end of an ADP molecule forming ATP. Adenine Ribose Adenine Ribose

2 Ways to make ENERGY! 1. Photosynthesis – takes place in the chloroplasts. 2. Cellular Respiration – takes place in the mitochondria.

Photosynthesis  Autotrophs make their own food by trapping light energy and converting it to carbohydrates. Equation: 6CO 2 + 6H 2 O + sunlight C 6 H 12 O 6 + 6O 2

The O 2 released by photosynthesis is made from the oxygen in water. Plants produce O 2 gas by splitting water 6CO 2 + 6H 2 O + sunlight C 6 H 12 O 6 + 6O 2 NOT a flashcard.

Cellular Respiration  The process of breaking down food molecules to release energy.  Occurs in the mitochondria. Equation: C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + ENERGY

Compare The Equations!  Photosynthesis:  Cellular Respiration: 6CO 2 + 6H 2 O + sunlight C 6 H 12 O 6 + 6O 2 C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + ENERGY NOT a flashcard.

Two Types of Respiration  Aerobic Respiration– requires oxygen.  Anaerobic Respiration– requires an absence of oxygen.

The End  Any questions?

Anaerobic Respiration  Two types: –Fermentation – occurs when bacteria break down plants (vegetables and fruit) and release alcohol or vinegar. –Lactic Acid Fermentation – occurs in muscles – a buildup of lactic acid causes soreness.

Sunlight Photo- System I Photo- system II NADP + ADP NADPH ATP Calvin CO 2 H2OH2O O2O2 ATP NAD + NADH Electron Transport System Cycle Citric Acid Heat CHLOROPLASTMITOCHONDRIA ATP Glycolysis Glucose Pyruvate Cycle NOT a flashcard.

Chemosynthesis  Some autotrophs can convert inorganic substances to energy.  Most are adapted to live in conditions where there is no oxygen. –Digestive tracts of mammals –Lake sediments –Marshes –Deep in the ocean

NOT a flashcard.

The End  Any questions?

Photosynthesis in a picture! NOT a flashcard.