ATP is Cell Energy Why do Cells need

ATP is Cell Energy

Why do Cells need Energy? • ATP powers most of the energyconsuming activities of cells, such as: Synthesis reactions. Examples: – joining transfer RNAs to amino acids for assembly into proteins – synthesis of all macromolecules – -photosynthesis – Active transport like sodium potassium pumps and endo and exocytosis – Cell reproduction

Why do Cells need Energy? • nerve impulses • adding phosphate groups (phosphorylation) to many different proteins, to alter their activity in cell signaling. • muscle contraction • beating of cilia and flagella (including sperm)

Using Cell Energy • When the third phosphate group of ATP is removed by hydrolysis, free energy is released. ATP + H 2 O → ADP + Pi + energy • ADP is adenosine diphosphate. • Pi is inorganic phosphate

Making Cell Energy ADP + Pi + energy→ ATP + H 2 O • requires energy • Energy comes from chemical bonds in food or from photosynthesis • occurs in the cytosol by glycolysis • occurs in mitochondria by aerobic cellular respiration

Recharging the Cell Battery ADP ATP Energy Adenosine diphosphate (ADP) + Phosphate Partially charged battery Energy Adenosine triphosphate (ATP) Fully charged battery

Have your Cell Energy and Eat it, too! LAB

Materials • 1 large marshmallow =ribose • 1 gummy bear= adenine • 3 small white marshmallows = inorganic phosphate groups • 3 regular toothpicks= covalent bonds • 1 colored toothpick= high energy bond

Procedure • Place 2 toothpicks on opposites sides of your RIBOSE • Connect one side with your adenine • One the other side, connect one phosphate • You now have AMP-> adenosine monophosphate

Procedure 2 • • Add 1 toothpick to other side of phosphate You now have ADP adenosine diphosphate Add 1 toothpick to other side of phosphate Add the colored toothpick to other side of the 2 nd phosphate • You now have ATP-> adenosine triphosphate

Procedure 3 • The colored toothpick represents the high energy bond between the two end phosphates that the important source of energy in ATP

ANALYSIS • Why is one toothpick a different color? • Write out the reaction showing ATP being used • Write out the reaction showing ATP being recharged • List at least 3 ways ATP can be used in cells • How do you make/recharge ATP?

Eat your ATP to make some more!