SNC4M “Public Health and Diseases”
Lifestyle: Nutrients and
Nutrition
Carbohydrates – Sugars and Starch
◦
Carbs provide immediate short-term
energy
Proteins
◦
Proteins provide structural support,
or important molecules like enzymes
Fats
Building Up and Breaking
Down
Breaking Down Macromolecules
(Large Nutrients like carbs, fats,
and proteins)
◦
This occurs in your digestive system: It takes
big molecules and makes smaller molecules
for absorption into your bloodstream; these
reactions are called
HYDROLYSIS
reactions
•
Building Up Macromolecules
This occurs in your cells as they collect the
small molecules from the bloodstream and
build them into larger material; these
reactions are called
CONDENSATION
Carbohydrates: Sugars and
Carbohydrates: Sugars and
Starches
Sugars
Sugars
Most names for sugars end in
–
ose
,
like
glucose, lactose, sucrose etc.
Often made of rings of carbon with O and H
coming off of the C’s
These single units are
mono
saccharides,
“single sugar”
OH
OH
H
H
HO
CH
2OH
H
H
H
OH
O
Glucose
H
OH
HO
O
H
H
HO
H
Ribose
CH
2OH
Secrets of Sugars video – fifth
estate I think
Also, see CSPI- MOH letter to
Health Minister Ambrose re:
nutrition labelleing; it’s a pdf in
my documents in the SNC4M
Building bigger carbohydrates
Building bigger carbohydrates
Occurs in your cells
Occurs in your cells
•
These small
mono
saccharides can be
chemically bonded to produce larger
carbohydrates, like
di
saccharides or
polysaccharides
Building sugars
Building sugars
Condensation Reactions
glucose glucose
monosaccharides disaccharide
maltose (dissacharide)
H2O
Glycosidic linkage
Note that water results from this reaction, hence “condensation” reaction. Also note the name of the bond – glycosidic link
+ H2O
Breaking Down Sugars
Breaking Down Sugars
Occurs in your Digestive System
Occurs in your Digestive System
Hydrolysis Reactions, “water breaking”
disaccharide
monosaccharides
Polysaccharides, or “Starch”
Polysaccharides, or “Starch”
•
Condensation Reactions can occur over
and over, producing very large
carbohydrates called
“
poly
saccharides’, or complex sugars
•
Common polysaccharides are starches
and cellulose in plants
Protein – Amino Acids
Protein – Amino Acids
Proteins contain
building blocks
called amino acids
There are 20
different types of
amino acids. Each
amino acid has a
different R group.
We will represent
an amino acid with
a rectangle.
—
N
—
Examples of different R
Examples of different R
groups:
groups:
The R groups give amino acids specific properties
Building proteins
Building proteins
Amino Acids will join together in
condensation reactions forming
long chains held together by
“peptide bonds”.
peptide bond
Protein structure & function
Protein structure & function
hemoglobin
Function depends on structure
◦
3-D structure
twisted, folded, coiled into unique shape
Protein structure
Protein structure
1°
3°
4°
2°
PolypeptidePolypeptide will naturally coil into alpha helices and beta pleated sheets, folding into a specific 3-D shape
The importance of the amino
The importance of the amino
acid sequence: Sickle cell
acid sequence: Sickle cell
anemia
anemia
This is a result of a mutation on the hemoglobin gene on the DNA which, through transcription and translation, results in a wrong amino acid. Sickle cell
Protein denaturation
Protein denaturation
Unfolding a protein
◦
conditions that disrupt the bonds
causes denaturation
temperature
pH
salinity
◦
alter structure
alter 3-D shape
◦
destroys functionality
some proteins can return to their functional
Lipids
Lipids
Structure:
◦
glycerol
(3C alcohol)
+
up to 3
fatty acids
fatty acid =
long HC “tail” with carboxyl (COOH) group
“head”
Building Lipids
Building Lipids
•
Up to 3 fatty acids linked to one
glycerol
•
Can form mono-, di- or triglyceride
Building Lipids
Building Lipids
Focus on fatty acids
Focus on fatty acids
All C bonded to H
No C=C double bonds
long, straight chain
most animal fats
solid at room temp
Unsaturated
fatty acids
• C=C bonds present • Kinks in the chain • Mostly oils
Saturated vs. Unsaturated
Saturated vs. Unsaturated
saturated
unsaturated
An Important Dietary Lipid:
An Important Dietary Lipid:
Cholesterol
Cholesterol
Important cell component
◦
animal cell membranes
◦
precursor of all other steroids
including testosterone, progesterone,
estrogen
Are all fats bad?
Needed to build cell membranes,
the sheaths surrounding nerves. It
is essential for blood clotting,
muscle movement, and
inflammation. For long-term health,
some fats are better than others.
Examples of good and bad
fats
Make a T-Chart
to compare good
and bad fats
including at least
