Transcript Chapter 2 The Chemistry of Life

Chapter 2
The Chemistry
of Life
DO NOW
 1) Grab a Chapter 2 packet and a weekly (Due
Friday)
 2) Use the information below to answer questions
on page 1
Atomic Number
Element Symbol
protons
electrons
Element Name
Atomic Mass
protons
neutrons
Today’s Learning Targets
 1) I can – differentiate between
elements, compounds, and
mixtures
 2) I can – differentiate between
ionic, covalent, and hydrogen
bonds
Section 1: Nature of Matter
 What is Matter?
 Matter: anything that has mass and
volume
 All matter consists of atoms  the
smallest unit of matter that cannot be
broken down
Think – Pair - Share
 Atoms consist of 3 subatomic particles
 Use the picture below to help you name and label
all three
Neutron (neutral)
Proton (positive
charge)
Electron (negative
charge)
Elements, Compounds, & Mixtures
 With your group, use the pictures below to
create a definition for an element, compound, and
mixture
 Element:
Compound:
Mixture:
Clean up – Close up
 1) I can – differentiate between elements,
compounds, and mixtures
 2) I can – differentiate between ionic, covalent, and
hydrogen bonds
 1 = Element
 2 = Compound
 3 = Mixture
DO NOW
1) Take out Chapter 2
packet
2) Complete p. Do Now
#1
3) Wait quietly to begin
Today’s Learning Targets
 1) I can – distinguish between
acids and bases
 2) I can – perform multiple pH
tests to draw conclusions on the
acidic or basic characteristics of a
solution
Aqueous Solutions
 The term aqueous means “dissovled in water”
 An aqueous solution is a mixture with substances
that are evenly distributed (they dissolve)
 Can you name some examples of aqueous
solutions?
 Because substances can dissolve in water they
can move easily throughout our body to our cells
 Ex: Sugar (sucrose) couldn’t get to our cells if it
wasn’t dissolved in water
Polarity
 We call water the “universal solvent”
 WHY? – Water is considered a “polar” substance
because of its positive and negative ends
(remember hydrogen bonds)
 Substances dissolve BEST in polar substances
like water
 A non polar substance – like OIL or FAT –
doesn’t dissolve in water well (separates)
 The properties of polar and non polar substances
are significant for living things
Think – Pair - Share
With your shoulder
partners, try to think
of two acids and two
bases to share with
the class
Acids and Bases
 Acids & bases are aqueous solutions
 When acids dissolve in water they form hydrogen
ions – H + , and make the solution more acidic
 Bases form hydroxide ions (OH-)
 Bases lower the acidity of a solution and make it
more basic
pH Scale
 All solutions have a pH value between 0 and 14
 0 – 6.9 = Acid
 7 = neutral
 7.1 – 14 = Base
Acid/Base Indicators
 An acid/base indicator is a substance that turns
to a specific color depending on whether it comes
into contact with an acid or a base
 Example Demo: Phenolphthalein – Turns pink for
base, colorless for an acid
 Other Examples: Red & Blue litmus paper
 Red Litmus – stays red for acid
 Blue Litmus – stays blue for base
Clean up – Close up
 I can – distinguish between acids and bases
 I can – perform multiple pH tests to draw
conclusions on the acidic or basic characteristics
of a solution
 1) Write your name on an index card.
 2) Give an example of an acid and base and give
their pH using the pH scale
DO NOW
1) Take out Chapter 2
packet
2) Complete p. Do Now
#2
3) Wait quietly to begin
Today’s Learning Targets
 1) I can – list two characteristics and
examples of each organic compound
 2) I can – describe the structures and
functions of each organic compound
 3) I can – explain the role and
significance of ATP in cells
Carbon Compounds
 Most matter in your
body that is not water
is made up of organic
compounds
 ALL organic compounds
have the atom carbon in
them
 They are usually
attached to hydrogen,
oxygen, and other
carbon atoms
4 Organic Compounds
 There are four classes of organic compounds
found in living things
 Carbohydrates
 Lipids
 Proteins
 Nucleic Acids
 Without these compounds, cells could not
function!
Research
 1) You will have the majority of the class to
research the characteristics, structures, and
functions of each biological molecule
 2) You will use your textbook – pages 34 – 37 to
complete your research
 3) **These are your notes! You are responsible
for taking good notes that you will use to study
for your upcoming test
 4) My PowerPoint on these molecules has been
uploaded to my website if you need extra
assistance when studying
Clean up – Close up

1) Grab an index card from the center basket and put your
name on it

2) List letters A, B, C, and D

3) Identify and name each biological molecule below
A
B
D
C
Carbohydrates
 Organic compounds made mostly of carbon,
hydrogen, and oxygen atoms
 Key source of energy
 Found in foods – fruits, vegetables, grains
 Monosaccharides: simple sugars, the building
blocks of carbs
 Ex: Glucose and Fructose
Monosaccharides
 If you can tell
me the chemical
formula for
glucose hold up
one finger
 Simple Sugars
Other Sugars
Disaccharides
 Double sugars
 Form when two
monosaccharides join
 Ex: Sucrose (table
sugar) contains
glucose and fructose
Polysaccharides
 Chains of 3 or more
monosaccharides
 Ex: Starch, Cellulose
(provides structural
support for plants)
Lipids
 Nonpolar molecules
that are not soluble
in water
 Ex.) Fats,
phospholipids (make
up lipid bilayer of cell
membranes),
steroids, and waxes
 Store Energy
Lipids
Saturated Fats
 Butter, lard, grease
 Considered “bad”
cholesterol
 Solid at room temp.
Unsaturated Fats
 Plant oils, olive oil,
fish oils
 Considered “good”
cholesterol
 Liquids at room temp.
Proteins
 Large molecules
 Examples:
 Amino Acids are the
 Collagen
building blocks of
proteins
 There are 20
essential amino acids
in proteins
 In skin, tendons,
ligaments
 Hemoglobin
 Carries oxygen
throughout your
body
Nucleic Acids
 All cells contain
nucleic acids
 Long chain of smaller
molecules 
nucleotides – consists
of 3 parts: a sugar, a
base, and a phosphate
group
 2 types of nucleic
acids:
 DNA- has 2 strands
of nucleotides that
spiral around each
other
 RNA- ribonucleic
acid- single strand of
nucleotides
DNA & RNA
ATP – Final biological molecule
 Adenosine
triphosphate –
single
nucleotide
with 2 extra
energystoring
phosphate
groups
 When food is broken
down inside cells,
some energy is stored
in ATP
 Cells need a steady
supply of ATP to
function
 ATP helps organisms
obtain materials,
move them around,
and get rid of waste
Food As Fuel
 Using the characteristics of the
different biological molecules we
discussed try to list at least two
foods rich in
 Carbs
 Proteins
 Lipids
DO NOW
1) Take out Chapter 2
packet
2) Complete p. Do Now
#3
3) Wait quietly to begin
Today’s Learning Targets
 1) I can – describe the role of
enzymes in chemical reactions
 2) I can – identify the effect of
enzymes on food molecules
Enzymes
 The chemical reaction in cells occur quickly and
at low temperatures because of enzymes
 Enzyme: substances that increase the speed of
chemical reactions
 Most enzymes are proteins
 Enzymes help organisms maintain homeostasis
Enzyme - Catalyst
 Most enzymes are catalysts: lower the activation
energy of a chemical reaction (speed up reaction
rate)
Why do we need them?
 Without enzymes chemical reactions in our body
would not occur quick enough for us to survive
 Ex: Amylase – helps break down glucose
 Ex: Carbonic anhydrase – increases the rate of a
reaction that releases carbon dioxide from your
body (increases the the reaction rate by 1 million
times!)
Enzyme Specificity
 Enzymes need their SPECIFIC substrate to
attach to in order to speed up a reaction
 Ex: Starch,
Amylase, Glucose
 An enzymes shape determines its
function/activity
 Enzymes have deep folds and pockets called
active sites
Lock & Key
 An enzyme acts only on a specific substrate
because only that substrate fits into its active
site
Factors in Enzyme Activity
 Any factor that changes the shape of an enzyme
affects the enzyme’s activity
 1. Temperature (too low or too high)
 2. pH value (each enzyme works best at a
different range of pH values)
Close up - Create an enzyme!
 1) Create an enzyme with a specific active site
 2) Create its “lock & key” substrate
 3) Name your enzyme (enzyme’s end with the
suffix “-ase” – Ex: amylase)
 4) Tell me what your enzyme is used for
 5) Give a detailed example of how your enzyme
may be destroyed
 ** These will be due on Tuesday 9/29, Chapter 2
Test on Monday**
DO NOW
 1) Turn in your weekly and
check off your name
 2) Grab a Chapter 2 study
guide from the front
 **Test Monday**
 3) Wait quietly to begin
Parts of an Atom
The Nucleus
The Electron Cloud
 The nucleus is
 The electron cloud is
 It contains the
 Surrounds the
located in the center
of an atom
protons and neutrons
the mostly made of
empty space
nucleus and is filled
with electrons
Elements
 Element- a pure substance made of only one kind of
atom
 There are more than 100 known elements, each
represented in the periodic table
What
elements are
found in living
things?
The Element Box
 Last year, we discussed the element box and
used it to determine the number of protons,
neutrons, electrons, the atomic number, AND the
atomic mass
 Lets Review This!
The Element Box
 The Oxygen Atom
Atomic Number
Element Symbol
p+
e-
Element Name
Atomic Mass
p+
How would you find JUST the number of neutrons
in an atom?
n0
Try it on Your Own!
 Complete the two examples in your notes for an
oxygen atom and a zinc (Zn) atom.
 Once your finished, take out the whiteboards
under your desk and draw just the oxygen atom
 Once the whole class is finished, I will ask for
specific answers for each atom!
Elements, Compounds, & Mixtures
 **Remember – Elements are pure substances
made of only one type of atom
 Compounds: are formed when two or more
different elements joined together
 Mixture: two or more substances are together
but not joined
Drawing Atoms
 **Remember the
protons and neutrons in
an atom are always in
the nucleus (the center)
 The electrons are in the
cloud
 Electron Levels:
 Level 1 = 2 electrons
 Level 2 = 8 electrons
 Level 3 = 18 electrons
Try it on Your Own!
 Using your whiteboards and your notes on the
oxygen atom, draw the oxygen atom placing all
subatomic particles in their correct places
Try it on Your Own!
 Draw a sodium atom on your whiteboards
 Use the information below to determine the
number of protons, neutrons, and electrons
Solutions, Acids,
& Bases
Section 3:
Chemistry of
Cells
Enzymes