KEY CONCEPT The cells of all organisms need chemical energy to carry out their life sustaining processes.

What do the cells need chemical energy for? To move To reproduce To grow To actively transport materials across the cell membrane (Ex. Endocytosis, exocytosis, sodium-potassium pumps) To carry out chemical reactions –Activation Energy Ex. Photosynthesis, respiration , All metabolism

Energy is stored in Food Molecules Chemical E is stored in the organic molecules found in food.

Carbohydrates and lipid molecules are the most important energy containing molecules in foods we eat.

Page 1: Title: ATP (write down the following then transfer on to your booklet on page one.) -Define ATP -Define ADP -How are ATP & ADP alike? -How are they different? Page 2: Title: ATP & ADP -Draw, Label, & COLOR Figure 4.2 on page 101 Summarize what you have learned about ATP in your own words. What is ATP and what is its role in the cell? Explain ATP energy transfers and the ATP/ADP cycle.

1. AUTOTROPHS – MAKE THEIR OWN FOOD MOLECULES USING ENERGY AND CARBON DIOXIDE (CO2) gas FROM THE ENVIRONMENT *

2 Groups of Autotrophs Photoautotrophs Chemoautotrophs

Photoautotroph – use light E to make their food through Photosynthesis CyanoBacteria Protists (Algae) Plants

Chemoautotrophs use chemical E to make their food through Chemosynthesis Ex. Archaebacteria

Autotrophs make the organic compounds that serve as food for themselves and all other organisms on Earth

2. Heterotrophs – Organisms that eat other organisms (or their products) to obtain energy and carbon compounds Animals Fungus Some Protists Most Bacteria ANIMALS

Are We Autotrophs or Heterotrophs?

Autotroph or Heterotroph?

Law of Conservation of Energy Energy cannot be created or destroyed but it can be changed from one form to another

Energy Transformations that Support Life

Two processes are needed to convert the sun’s light energy into chemical energy the cell can use. PHOTOSYNTHESIS and CELL RESPIRATION

In photosynthesis, sunlight E is transformed into chemical E stored in food molecules Starch Glucose

In cell respiration, the chemical E stored in food molecules is released and repackaged into high energy molecules called ATP the cells can use.

ATP What happens to the E released from food in cellular respiration? It is used to make high energy molecules called ATP

What is ATP? ATP stands for the molecule Adenosine Triphosphate

ATP is a high energy containing molecule used by all cells to carry out cellular functions.. Sodium-Potassium Pump Muscle contraction

ATP – ADP ATP – Adenosine Triphosphate ADP – Adenosine Diphosphate

The ATP – ADP cycle ATP –High energy molecule ADP –Low energy molecule phosphate removed

When ATP loses a phosphate molecule it gives off E and becomes ADP. The E given off is used to power chemical reactions in the cell

When ADP gains E and a phosphate molecule, it becomes “recharged” to form ATP. The E source to “recharge” ADP comes from the breakdown of food through respiration.

This process is called the ATP – ADP Cycle

Removing a Phosphate - Release Energy “use the battery” ATP Energy + P + ADP   Adding a Phosphate – Stores Energy “recharge battery” ADP + Energy + P ATP

This is constantly occuring in every cell of your body, millions of times a minute! The E given off is used to power every chemical reaction occuring in the cell

ATP to ADP Recharging your body’s batteries