Transcript Cellular Energy!!

Do Now!! 
What is energy?
What is the ultimate source of energy on
the earth?
Where do we get our energy from?
Objectives
 To define energy.
 To list the different types of energy.
 To explain the laws of thermodynamics.
 To begin discussing photosynthesis and cellular
respiration
Section 8.1: How organisms
obtain energy!!
So what is energy??
 EnergyThe ability to do work!!
 Thermodynamicsis the study of the flow and transformation of
energy in the universe.
3 Types of Energy
Chemical
Potential
Kinetic
3 Types of Energy
 Potential- stored energy, or energy of position
Ex: top of the rollercoaster!
 Kinetic- motion
Ex: moving down from top of rollercoaster!
 Chemical- energy found in bonds (released
when bonds are broken, stored when bonds
are formed)
Ex: lighting a match (released or stored?)
Laws of Thermodynamics
 First law —energy can be converted from one form
to another, but it cannot be created nor destroyed.
 Ex. Stored energy to chemical energy to
mechanical energy
Do Now!!  (P. 6)
What is the first law of thermodynamics?
What are the three types of energy?
How can plants harness energy from the
sun?
Objectives
 To discuss the second law of thermodynamics
 To define metabolism and differentiate
between anabolic and catabolic pathways.
 To define ATP
 To read and analyze the article “Will we ever
photosynthesize like plants?”
Laws of Thermodynamics
Second law —energy cannot be
converted without the loss of usable
energy.
Ex. Energy Lost as Heat
Second Law of Thermodynamics
 Entropy
Measure of unusable energy in a system.
Ex: thermal energy
 Entropy always increases.
Do Now!! 
Please take out your homework!
What are the 2 laws of thermodynamics?
What is entropy?
What is metabolism?
Objectives
 To define metabolism and differentiate
between anabolic and catabolic pathways.
 To define ATP
 To be able to list the inputs and outputs of
photosynthesis.
 To be able to identify the structures of a
chloroplast.
 (“Quest” on photosynthesis next week!)
Review of Reactions…
 Endothermic- uses energy to make bonds
H + H
H2
Energy put in
 Exothermic- breaks bonds and releases
energy
 H2
H + H
Energy Released
Autotrophs and Heterotrophs
o Autotrophs: make their own energy
Ex:
o Heterotrophs: have to eat to obtain energy
Ex:
Do Now!!  (P.2)
What is the first law of thermodynamics?
The second law?
What is entropy?
Objectives
To define metabolism and differentiate
between anabolic and catabolic
pathways.
To define ATP
To read and analyze the article “Will we
ever photosynthesize like plants?”
Metabolism
 Metabolism:
All chemical reactions in a cell
 Two types of Metabolic Pathways:
Catabolic: Release energy by breaking
down larger molecules
Anabolic: Use energy to build larger
molecules from smaller ones
Think- Pair - Share
 Of the following examples, list which ones are
catabolic and anabolic
1. Amino acids becoming polypeptide
chain
2. Glucose becoming glycogen
3. Your body breaking down food
4. Lifting weights and building up muscle
mass
Adenosine Tri Phosphate (ATP)
 ATP: most important biological molecule that provides
chemical energy
 Structure:
 Adenine base, ribose sugar, and 3 phosphate groups
 Function: Releases energy when bonds are broken
Processes involving Energy…
 Cellular respiration —organic
molecules are broken down to release
energy for use by the cell
-type of process:
 Photosynthesis —light energy from the
Sun is converted to chemical energy
for use by the cell
-type of process:
Next up… Photosynthesis!!