Download (acid) (base)

Name the 4 Macromolecules
needed by living things.
DO NOW
• Oct 13th
Name the monomer for each of the
4 MACROMOLECULES needed by
living things.
DO NOW
• Oct 14th
I. Water - the most important inorganic
(has no carbon) compound
- Water is a polar compound with
charged ends (+ and -). It forms polar
covalent bonds - electrons are
unevenly shared.
H+
H+
O-
H20 cont’d
• Water is called the
“universal solvent”
• Most cell reactions take
place in water
A. Chemical Formula - just shows
atoms
HOH (another way of writing H20)
B. Structural formula - shows
chemical bonds + atoms
H
H
O
II. Acids + Bases
- always caused by solutions having H+
ions.
- pH scale is uses to measure how strong
acids + bases are. pH measures H+
concentration.
0 ------------- 7 --------------14
ACIDS
BASES
NEUTRAL
Dissociation (breaking apart a
compound into opposite
charges)
HOH -----> H+ +
(acid)
OH (base)
HCl ------> H+ +
(acid)
Cl (base)
• Cohesion- an attractive force between
molecules of the same kind
• Ex: between water molecules in a drop of
water
• Adhesion- an attractive force between
unlike substances
• Ex: between water molecules and the walls
of a straw
• Capillarity- together adhesion
and cohesion allow water to
move upward through narrow
tubes against the force of
gravity
CHAPTER 3
III. Organic compounds
(Chapt. 3)
• Always contain carbon
• carbon atoms form very large
molecules in long chains
• macromolecules - large, complex
molecules usually containing carbon
IV. 4 kinds of organic molecules
necessary for life
- proteins, lipids, carbohydrates, nucleic
acids
Functional Groups
• Definition: Cluster of atoms in a
compound that influences the
properties of that compound
• Example: -OH group=Hydroxyl group
– Found in alcohols
-PO4- = phosphate group
3 phosphate groups found in ATP
ATP- bonds between 3 phosphate
groups yield energy when they are
broken
V. Carbohydrates - provide
quick energy release
A. Contain only C, H, and O in a ratio of 1
C to 2 H to 1 O
B. EX. Sugars, starches, cellulose
C. Are made of simple sugars called
monosaccharides. All have the formula
C6H12O6. EX. Glucose (blood sugar),
fructose (sugar in fruit), galactose
Glucose Molecule
Example: Monosaccharide:(means “one
sugar”) also called simple sugar
H2OH
H2OH
H C
O
H
OH C
C
C
OH C
H
H
H
H
OH
O
H
C OH
OH
Glucose C6H12O6
C
C
OH
H C
H
H
C OH
OH
Galactose C6H12O6
These are examples of structural isomers: They
have the same chemical formula but different
structural formulas (they look different)
Building carbohydrates:
• Monosaccharides combine by a
process called dehydration
synthesis
• Dehydration = losing a molecule of
H2O
• Synthesis = putting together
• 2 monosaccharides bond together
and one molecule of H2O is split off
CARBOHYDRATES CONT’D
D. Disaccharides - double sugars formed
by combining 2 monosaccharides
EX. Lactose = glucose + galactose
(sugar in milk)
Sucrose = glucose + fructose
(table sugar)
E. Polysaccharides Definition: Macromolecules made of
many sugars
1. Starch (amylose) - made of glucose
units
2. Glycogen - long chains of glucose
units stored by animals. Liver +
muscle cells are made of glycogen
3. Cellulose - made of glucose units that
are linked together by plant cells animals can’t digest it
Breaking down carbohydrates
• If polysaccharides are used for
energy , they must be broken down
into monosaccharides.
• This process is called hydrolysis
because a molecule of HOH is
split.
• It takes 1 HOH molecule to break
the bonds between 2
monosaccharides.
VI. Lipids
• lipids store energy + are found in the
cell membrane
• Examples: Fats, waxes, + oils
• Triglycerides made of a glycerol
molecule bonded to 3 fatty acids
glycerol (3 carbon molecule)
fatty acids
LIPIDS CONT’D
A. Saturated fats (SOLID)
• when the 3 fatty acids are lined up side
by side – no carbon-carbon double
bonds -carbon atoms in the fatty acid
chains are filled (saturated) with
hydrogen atoms
• EX. Butter, lard, chocolate, coconut oil,
beef
• raise blood cholesterol level
• usually solid at room temperature
LIPIDS CONT’D
B. Unsaturated fats (FLUID)
• when the 3 fatty acids are spread
apart and have kinks in them because
the C atoms are not filled with H
atoms – have carbon-carbon double
bonds
• liquid at room temp.
• EX. Olive oil, canola oil, peanuts, fish
oil
• unsaturated fats can be made into
saturated fats by adding H atoms
Phospholipids
• Glycerol, 2 fatty
acids and a
phospholipid
head
• Main components
of cell
membranes
VII. Proteins
• made of chains of amino acids
• most proteins have about 100 amino
acids that are coiled around each
other so they look globby
• humans use about 20 different kinds
of amino acids
• Proteins are used for cell growth,
repair, and maintenance
• Sometimes must be coupled with
other proteins to work
Amino acid structure
• 4 parts:
– 1. Central carbon atom
–2. an amino group (NH2)
–3. a carboxyl group (COOH)
–4. an “R” group – there are about
2O different amino acids, each
with a different R group.
–Amino acids may contain C, H,O,
N, and S
Protein Structure
• 2 connected amino acids make
a dipeptide
• A protein is also called a
polypeptide chain
Types of proteins
1. Globular proteins - twisted and
folded. EX. Hemoglobin (blood
protein that picks up O2)
2. Collagen - fibrous protein that
makes up cartilage, skin, bones,
tendons
3. Keratin - hair, feathers, rhino +
giraffe horns, finger nails
4. Enzymes – special type of
proteins that speed up chemical
reactions
• Enzymes are called “biological
catalysts.”
• They speed up reactions.
• They are not broken down
during the reaction
• Enzymes are specific! – each
reaction needs its own enzyme.
VIII. Nucleic acids
• Made of subunits called nucleotides
which are grouped into units called
genes
1. DNA - made up 2 coiling strands
called a double helix (which looks like
a twisted ladder (see next slide -->)
• provides the genetic code for making
proteins
• exists in the cell as compact bodies
called chromosomes
Double Helix
NUCLEIC ACIDS CONT’D
2. RNA
• Ribonucleic acid
• 3 kinds help DNA build proteins:
mRNA, tRNA, rRNA
• Decodes DNA messages into
amino acid sequences
• single stranded
RNA