Teacher Notes
Unit 2: The Chemistry of Life
Quick Chemistry: Matter ​
(sketch and label a simple atom below)
Opposite charges ___​
attract​
____, like charges ____​
repel​
____.
Quick Chemistry: Water
? How does water support life on Earth?
Polarity ​
- unequal sharing of electrons gives a slight positive or negative behavior to an atom
Sketch:
Oxygen has more protons, so it attracts electrons more strongly.
Hydrogen Bonds
Polarity causes _​
hydrogen​
___ bonds when partially positive hydrogens are attracted to partially negative
oxygen (see sketch above)
Unit 2: The Chemistry of Life 1 F2015 Teacher Notes
Properties of Water
Cohesion - water has a tendency to “stick” to itself
Adhesion - water has a tendency to “stick” to other polar things
Hydrophilic - “water-loving”, having a tendency to interact with water molecules, usually polar
Hydrophobic - “water-fearing”, having a tendency to ​
not​
interact with water molecules, usually
nonpolar
Capillary Action - the tendency of water to “creep up” a substance, espc. the in a narrow tube
Density - water has a lower mass per unit volume as a solid than as a liquid; this is unique to water
Solvent - water can dissolve more substances than any other liquid on earth
Solutes and Solvents​
(sketch below)
Heat Capacity - water has the ability to absorb and store significant amounts of heat
Unit 2: The Chemistry of Life 2 F2015 Teacher Notes
? What are the building blocks of life?
The Chemistry of Life
The elements that make up the molecules of living things are
through birth and death
ultimately recycled
​
The Primary Atoms of Living Organisms
Carbon (C)
Oxygen (O)
Hydrogen (H)
Nitrogen (N)
Phosphorous (P)
Diagram a carbon atom and show where/why carbon is stable making four chemical bonds (sketch below)
Carbon will can easily make _4__ stable bonds, including bonding to itself
Carbon will readily bond to itself (sketch single, double, and triple bonds, lattice or sheets, and a ring
configuration of carbon)
Unit 2: The Chemistry of Life 3 F2015 Teacher Notes
Quick Chemistry: Molecular Bonds
Covalent Bond
Ionic Bond
atoms SHARE electron pairs
atoms EXCHANGE an electron
Sketch
Sketch
It is difficult for carbon to ​
lose​
or ​
gain​
4 electrons in an _________ bond, so it usually forms strong
_______________ bonds.
Compound - a pure substance made up of two or more types of atoms
Organic Compound - compounds that are essentially built on carbon
Ion - an atom or molecule with a ‘formal’ electrical charge
Ions interact with polar molecules
Functional Groups
Functional Group - clusters of atoms that determine the characteristics of a chemical compound
R Group - placeholder for a carbon side chain
Handles : Tools :: ___________: molecules
Heads : Tools :: ___________________: molecules
(sketch and label the analogy above)
Unit 2: The Chemistry of Life 4 F2015 Teacher Notes
The Macromolecules
Macromolecules - large molecules containing a very large number of atoms
Monomers - individual building blocks of macromolecules; bind to form polymers
Polymers - long chains of repeating subunit molecules (monomers)
The Four Macromolecules of Life
Carbohydrates
Lipids
Proteins
Nucleic Acids
C, H, O
C, H, O, P
C, H, O, N, S
C, H, O, N, P
sugars, glucose, starch
fats, steroids,
membranes
enzymes, muscle,
antibodies
DNA, RNA, ATP
Monomer
Monosaccharide
Fatty Acids
Amino Acid
Nucleotide
Function
Provide and store
energy
Store energy, form
cell membranes
Cell structure, cell
function, chemical
reactions
Hold information
to make proteins
Elements
Examples
Monomers of Macromolecules
Carbohydrate
Amino Acid
(sketch)
(sketch)
Lipid
(sketch)
Nucleic Acid (sketch)
Unit 2: The Chemistry of Life 5 F2015 Teacher Notes
Carbohydrates [Sugars]
Mono​
saccharide​
- monomer of carbohydrates; usually a carbon ring with
an oxygen atom
○ ex: glucose, fructose, galactose
Poly​
saccharide ​
- a chain of monosaccharides
sketch
!
The C-C bonds in carbohydrates ​
store energy​
for quick use by cells, and form strong, rigid
cellulose​
____ in plants.
Lipids [Fats]
Fatty Acid - monomer of lipids; usually a glycerol + 3 fatty acid ‘tails’
○ found in: butters, oils, waxes, fat
Phospholipid - lipids of cell membranes; have a hydrophilic head and hydrophobic tails
sketch
!
The hydro​
phobic​
tails of lipids make them ____​
insoluble​
____ in water, and therefore they make good
waterproof barriers within cells.
Unit 2: The Chemistry of Life 6 F2015 Teacher Notes
Nucleic acids
Nucleotide - monomer of nucleic acids; usually a 5-carbon sugar + a nitrogen base
○ DNA - deoxyribonucleic acid; the information storage molecules in most cells
sketch
!
Like letters in a sentence, the order of the ____​
nitrogenous bases​
____ encodes biological information
in every organism known.
Amino acids
Amino Acid - a monomer of proteins, always an NH4 group and a COOH attached to some carbon
backbone.
Polypeptide - a chain of amino acids, folds like magnets on a string to form complex protein
structures
○ Peptide Bond - a covalent bond between amino acids
sketch
!
Some amino acids are ___​
polar​
_____, while others are ____​
non-polar​
_____. This characteristic allows
polypeptide chains to fold into complex structures called ___​
proteins​
____, which are necessary for
nearly every chemical process within cells.
!
Of the millions of possible amino acids, only _~​
20​
__ are used by Earth’s life.
!
The ____​
RNA World​
____ hypothesis claims that _​
RNA​
_ was the first biomolecule in the evolution of
life on Earth.
Unit 2: The Chemistry of Life 7 F2015 Teacher Notes
Chemical Reactions
Reactant - the starting materials of a chemical reaction
Product - the end products of a chemical reaction
!
!
___​
energy​
___ is stored in ________​
chemical bonds​
_________.
An organism’s ​
metabolism​
rearranges atoms using energy from chemical reactions
Endergonic and Exergonic
Exergonic - chemical reactions that give off energy; energy is a product
Endergonic - chemical reactions that require the addition of energy
Activation Energy - the amount of energy required to start a chemical reaction
Catalyst - reduce the amount of activation energy required for a chemical reaction
Biological Chemical Reactions
Enzyme - ​
proteins​
that accelerate biological chemical reactions
○ Active Site - the part of an enzyme that actually performs the chemical reaction
○ Substrate - the molecule that the enzyme acts upon
Lock and key - substrates fit into the active site of enzymes like a lock into a key
Induced fit model - enzymes change shape when participating in a chemical reaction
Competitive Inhibition
Noncompetitive Inhibition
Explain: block enzymes at active site
Explain: block enzymes, but not from active site
sketch
sketch
Unit 2: The Chemistry of Life 8 F2015 Teacher Notes
Biological Energy
ATP - energy-carrying molecule that powers cell processes
○ Like: batteries that give energy to enzymes
sketch
ADP - uncharged ATP, needs another phosphate added to it
○ P​
i​ inorganic phosphate, “recharges” ADP to ATP
Unit 2: The Chemistry of Life 9 F2015