Transcript Lecture Notes 3: Biochemistry

Lecture Notes 3:
Biochemistry
Biology A
Eaton Rapids High School
K.Coppins
I. Basics of Chemistry
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A. The Atom
Smallest unit of any element
 1. ______________________________
positive nucleus
 2. Made of a __________________
surrounded by a cloud of negative
electrons
particles called ____________.
 3. All elements are listed on the
Periodic Table
_____________.
I. Basics of Chemistry

A. The Atom
 4. Elements in the body:
 Oxygen (65%)
 Carbon (18%)
 Hydrogen (10%)
 Nitrogen (3%)
 Calcium (1.5%)
 Phosphorus (1.0%)
 Potassium (0.35%)
 Sulfur (0.25%)
 Sodium (0.15%)
 Magnesium (0.05%)
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Copper, Zinc, Selenium,
Molybdenum, Fluorine,
Chlorine, Iodine,
Manganese, Cobalt, Iron
(0.70%)
Lithium, Strontium,
Aluminum, Silicon, Lead,
Vanadium, Arsenic,
Bromine (trace amounts)
Reference: H. A. Harper, V. W.
Rodwell, P. A. Mayes, Review
of Physiological Chemistry,
16th ed., Lange Medical
Publications, Los Altos,
California 1977.
I. Basics of Chemistry

B. Molecules
 1. When two or more atoms join
molecule
together, they form a ___________.
chemical bonds
 2. These are called _______________,
and are based on interactions between
electrons
the _________.
 3. If a bond joins different elements,
compound
the new substance is a __________.
I. Basics of Chemistry

C. Types of Bonds
Ionic bonds
 1. _____________
a. Electrons move from one atom to
the other.
b. Atoms become positively or
negatively charged; called ____.
ions
c. Charges attract or repel.
conducting electricity
d. Good for __________________.
I. Basics of Chemistry

C. Types of Bonds
Covalent bonds
 2. _______________
a. Electrons are shared between two
atoms.
b. Atoms must remain together
c. Bonds are flexible
large structures
d. Good for ________________.
I. Basics of Chemistry

C. Types of Bonds
Hydrogen bonds
 3. _______________
a. Hydrogen holds electrons weakly
b. Has a slightly positive charge,
attracted to anything negative.
c. Creates weak bonds that help hold
structures but can be broken easily.
DNA, hair, water
d. Examples: _________________
I. Basics of Chemistry

D. Molecules and Energy
 1. Energy is stored in the bonds
between atoms. Energy is required to
make or break bonds.
______________
 2. The amount of energy varies with
the type of bond. Some bonds
(hydrogen) are easily broken while
others (triple covalent) are very hard.
II. Water Chemistry
A. ________
Water
is the most abundant
chemical in the body.
 B. Water has many characteristics that
make it vital to our bodies.
Size
 1. _____—water
is a very small
molecule, so it moves fast and can
squeeze into tiny crevasses between
other molecules.

II. Water Chemistry

B. Water has many
characteristics that make it
vital to our bodies.
Polarity
 2. _________--Hydrogen
has a slightly positive
charge while oxygen has a
slightly negative charge.
This makes it easy for
water to pry apart other
charged molecules,
dissolving them. Called a
Universal Solvent
__________________.
II. Water Chemistry

B. Water has many characteristics that
make it vital to our bodies.
Crystal structure
 3. _______________--Due
to polarity,
water forms a crystal structure that is
less dense than liquid water.
II. Water Chemistry

B. Water has many characteristics that
make it vital to our bodies.
Heat capacity
 4. _____________--water
absorbs and
releases heat energy slowly, and can
hold a great deal of heat energy. This
helps organisms maintain their body
temperature in the safe range.
II. Water Chemistry

B. Water has many
characteristics that make it
vital to our bodies.
 5. __________________-Cohesion & Adhesion
Polarity allows water to
stick to itself (cohesion)
and to any charged
material (adhesion).
Water can glue materials
together.
II. Water Chemistry

B. Water has many
characteristics that make
it vital to our bodies.
Buffer
 6. _______--Water
can act as either an
acid or a base,
maintaining a stable
pH in our bodies.
III. Macromolecules

A. What are they?
Very large molecules that make
 1. __________________________________
most of the structure of the body
_______________________________________
 2.
Made of smaller pieces called
monomers that can be assembled like
__________
legos to form a variety of structures. A
large chain of monomers is called a
polymer
_________.
III. Macromolecules

B. Carbohydrates
monosaccharide (sugar)
 1. Monomer: ____________________
polysaccharide (starch)
 2. Polymer: _____________________
rings of carbon with
 3. Structure:______________________
oxygen and hydrogen attached; CH2O
________________________________
energy, plant structure
 4. Uses: ___________________
sucrose, cellullose
 5. Examples: ________________
Examples of Carbohydrates
III. Macromolecules

C. Lipids
fatty acid
 1. Monomer: __________
lipid or fat
 2. Polymer: ___________
3 long chains of carbon
 3. Structure:______________________
hydrogen on a glycerol molecule
________________________________
energy, structure, warmth
 4. Uses: ________________________
fat, oil, cholesterol
 5. Examples: ____________________
Examples of Lipids
III. Macromolecules

D. Protein
amino acid (20)
 1. Monomer: _______________
protein or polypeptide
 2. Polymer: _____________________
central carbon atom with
 3. Structure:______________________
________________________________
hydrogen, amine, carboxyl, & R groups
structure, emergency energy
 4. Uses: ________________________
skin, insulin, enzymes
 5. Examples: ____________________
Examples of Proteins
III. Macromolecules

E. Nucleic Acids
nucleotide (5)
 1. Monomer: _______________
nucleic acid
 2. Polymer: ___________
5-carbon sugar attached
 3. Structure:______________________
to nitrogen base and phosphate group
________________________________
stores genetic code
 4. Uses: ___________________
DNA and RNA
 5. Examples: _______________
Examples of Nucleic Acids
IV. ATP
adenosine triphosphate
A. ATP stands for _____________________
 B. Cells use ATP as a __________________
rechargeable battery
3 phosphates
 C. Made of adenine with ___
 D. Lots of energy is stored in the bond
the second and third phosphates
between _____________________________
 E. When this bond is broken, tremendous
energy is released.
 F. The pieces are then reassembled, storing
more energy for another use.

Examples of ATP
V. Enzymes

A. Special proteins that
speed chemical reactions
 1. Chemical reactions
require a certain
activation energy to
_______________
get started.
 2. Enzymes decrease
this energy, making
reactions occur faster.
V. Enzymes

B. Lock-and-Key Model
 1. Enzymes are not used up by the
reaction, but each can only work on one
enzyme specificity
reaction (________________).
 2. This is called the lock-and-key model
key
of enzymes. An enzyme is like a _____
which can open exactly one _____.
lock If
you want to “unlock” another reaction,
you need a different enzyme.
V. Enzymes
V. Enzymes

C. Factors which affect enzymes
Temperature
 1. _____________--enzymes,
like all
proteins, change shape when exposed
to heat or cold. Each has an optimal
temperature range.
pH
 2. ____--all
enzymes have an optimal
range of pH. Example: stomach
Concentration
 3. _____________--having
more
enzymes makes the reaction faster.
Images used in this presentation
were obtained from:
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Atom: PowerPoint clipart
Water molecule and Water attraction:
stainsfile.info/StainsFile/jindex.html
Bohr water molecule: ghs.gresham.k12.or.us
Spoon on nose: statweb.calpoly.edu
pH scale: bcn.boulder.co.us
Glucose and Cellulose: www.greenspirit.org.uk
Sucrose: encarta.msn.com
Images, continued
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Saturated and unsaturated fatty acids, cis and
trans fat, and lipid molecule: biology.clc.uc.edu
Generic Amino acid: ffden-2.phys.uaf.edu
Peptide bond: www.rothamsted.bbsrc.ac.uk
Nucleotide: faculty.uca.edu
DNA helix: www.biologycorner.com
ATP: textbookofbacteriology.net
Activation energy: faculty.clintocc.suny.edu
Enzyme lock-and-key: www.celltech.com