Do Now – Socrative rm 420161
1. What is energy?
a. The ability to move
b. The ability to do work
c. All chemical reactions in a cell
2. What organism can make its own food?
a. Autotroph
b. Heterotroph
c. Phototroph
3. What is the idea that energy cannot be created or
destroyed?
a. First Law of Thermodynamics
b. Second Law of Thermodynamics
c. Third Law of Thermodynamics
Objectives
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To define energy.
To list the different types of energy.
To explain the laws of thermodynamics.
To understand the general idea of
photosynthesis and respiration.
Cellular Energy!!
Chapter 8
8.1: What is energy?!
 Energy The ability to do work
 Thermodynamics is the study of the flow and transformation of
energy in the universe.
Types of Energy
ATP
Types of Energy
 Potential- stored energy, or energy of
position.
 Kinetic- motion
 Chemical- energy found in bonds
( released when bonds are broken)
Laws of Thermodynamics
 First law —energy can be converted from
one form to another, but it cannot be
created nor destroyed.
 Ex. The body converts stored energy in
food into Chemical Energy
Laws of Thermodynamics
 Second law —energy cannot be
converted without the loss of usable
energy.
 Ex. Energy Lost as Heat
(some energy is changed
to thermal energy)
Second Law of
Thermodynamics
 Entropy
 Measure of disorder (randomness)
 Measure of unusable energy
 Entropy always ___________.
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
 Autotrophs are organisms that make their
own food.
-Ex. Plants
 Heterotrophs are organisms that need to
ingest food to obtain energy.
 Ex. Animals
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
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1. Amino acids becoming polypeptide chain
2. Glucose becoming glycogen
3. Your body breaking down food
4. Fatty Acids becoming triglycerides
Adenosine Tri Phosphate
(ATP)
 Structure:
 Adenosine Molecule, a ribose sugar, and 3
phosphate groups
Processes involving
Energy… Exit Ticket:
 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:
§ Entropy is _________________.