Energy UnitReview- Ch. 5

Types of energyCapturing energyReleasing energy

Energy – the ability to do work• The Law Of Conservation of Energy:

• Energy cannot be created or destroyed, it can only be transformed (changed) from one state to another.

• Energy can be divided into two main groups

• Potential energy = stored energy• Kinetic energy = moving/working energy

• Can potential energy be turned into kinetic energy? YES

• Can kinetic energy be turned into potential energy? YES

STATES OF ENERGY

Potential and kinetic energy exist in many forms:

Forms of energy:• Mechanical – energy with which moving objects

perform work• Chemical – energy stored in substances• Heat – produced by molecular motion of matter• Light – moves in waves• Nuclear – stored in nucleus of atoms• Electrical – movement of electrons

CHEMICAL REACTIONSA + B AB

AB A + BReactants Products

MetabolismThe sum of all the chemical

reactions occurring in an organism

Exothermic

Energy is released(BREAKDOWN OF GLUCOSE)

AB A + B

Endothermic

Energy is absorbed(BUILDING MACROMOLECULES- Like Glucose)

A + B AB

EnzymesProteins that

increase the speed of a chemical reaction by

lowering the activation energy

(the energy needed to start a reaction)

PHOTOSYNTHESIS

6CO2 + 6H20 C6H12O6 + 6O2

reactants products Carbon dioxide + water glucose + oxygen

STEP ONE

The Three Steps of Photosynthesis

STEP 1:Chlorophyll

traps energy from

sunlight.

(Chloroplasts have small disks, Thylakoids that

contain chlorophyll.)

The Three Steps of PhotosynthesisSTEP 2:

Captured Light Energy is used to make ATP

in the thylakoid

ATP is used as Activation

Energy to start the

Calvin Cycle

The Three Steps of PhotosynthesisSTEP 3:

Calvin Cycle:Cells use the energy from breakdown of ATP to make

carbohydrates (glucose) from

the carbon atoms in CO2

REACTIONS OF PHOTOSYNTHESIS

LIGHT REACTION• Can only occur

when light is present

• Products:– ATP– Oxygen

CALVIN CYCLE• The “Dark Reaction”• Doesn’t need light,

but needs products from light reaction (ATP!!!)

• Products:– Glucose

Please add this to the back of your notepage.

• Sunlight is _____________________ energy• Carbon dioxide and water are rearranged to

produce _______________________• ___________________ is a by-product (waste

product) of photosynthesis• ______________________ is used by plants and

animals for energy. Glucose is ________________ energy

KINETIC (LIGHT)

GLUCOSE (SUGAR) AND O2

OXYGEN

CHEMICAL (POTEN.)

GLUCOSE

Please write the questions on the

back of your notepage and answer them.

Cellular Respiration – releases the energy in food and turn it

into a form that can be used for the activities of life

C6H1206 + 602 6CO2 + 6H2O + 36 ATP

ORSugar + oxygen carbon dioxide + water + energy

Identify products and reactants

2 types of CR

Aerobic:• Takes place when

oxygen is present• Yields 36 ATPS (a

lot!)

Anaerobic:• Takes place when

oxygen is NOT present.

• Yields only 2 ATPs• Some organisms

are completely anaerobic

AEROBIC RESPIRATIONO2 present. Lots of Energy!

• 1st glucose moves from the blood into a cell’s cytoplasm where it is split in ½ – Creates:

• Pyruvic acid• 2 ATP

• Pyruvic Acid moves into mitochondria to be broken down further resulting in

ATPs.For a grand total of _____ ATPs

34

36

Lactic Acid Fermenation

• When animal muscles use so much energy the oxygen runs out

• Some bacteria also produce lactic acid, which is used to make some foods.• Produces:

– 2ATP– lactic acid

Alcoholic Fermentation

• Small organisms that are in environments without oxygen– Yeast– Bacteria

• Produces:– 2 ATP– Alcohol