Download Ch 2d power point


After students complete the pH lab,
they will have a basic understanding
of which substances are classified as
acids or bases as recorded in the pH
Lab Data table. Students will also
observe and be able to describe the
reaction between an acid and a base
when they are added together.

After discussing what
carbohydrates are and looking at
the molecular models in the
power point, students will
identify simple and complex
carbohydrates by stating which
foods contain them.
Contains carbon
 (Carbon dioxide & carbon
monoxide contain carbon, but
they are inorganic)
 Carbon is electroneutral
 Means it never loses or gains
electrons, it always shares


Organic compounds in the body
include:
 Carbohydrates
 Lipids
 Proteins
 Nucleic Acids

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Contain carbon, hydrogen, and
oxygen
Includes sugars and starches
Their major function is to supply a
source of cellular food
Classified as monosaccharides (one
sugar), disaccharide (two sugars),
and polysaccharide (many sugars)
Figure 2.13a
 Monosaccharides
or simple sugars
 Monosaccharides
are the building
blocks of all other carbohydrates
Figure 2.13a

Disaccharides or double sugars

Disaccharides are formed when 2
monosaccharides are joined by a
dehydration synthesis reaction.

Disaccharides are decomposed
back into monosaccharides by a
hydrolysis reaction. (water added)

Polysaccharides or polymers are
long chains of simple sugars
Figure 2.13c

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Important polysaccharides to the body –
starch and glycogen – both are polymers of
glucose
Starch


Storage carbohydrate of plants
Glycogen
Storage carbohydrate of animals
 Stored in muscles and the liver
 When blood sugar levels drop, liver cells
break down glycogen and release glucose into
the blood

Starch
Monosacchrides

After discussing what carbohydrates
are, looking at the molecular models
in the power point, and performing
the starch lab, students will identify
simple and complex carbohydrates,
and state which foods contain them.
Students will be able to test for the
presence of starch in foods.

After discussing what carbohydrates
are, looking at the molecular models
in the power point, and performing
the starch lab, and Simple sugar lab
students will identify simple and
complex carbohydrates, and state
which foods contain them. Students
will be able to test for the presence of
starch and simple sugars in foods.
NOW!

After discussing what lipids are
and looking at the molecular
models in the power point,
students will identify lipids and
state which foods contain them.
Students will be able to explain
why lipids are important to our
bodies.

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Insoluble in water
Contain C, H, and O, but the
proportion of oxygen in lipids is less
than in carbohydrates
Examples:
 Neutral fats or triglycerides
 Oils
 Phospholipids
 Steroids
 Waxes

Fats store energy, help to insulate the
body, and cushion and protect organs
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
lipids are important parts of
biological membranes and
waterproof coverings

Oils (liquid) unsaturated fat

Fats (solid) Saturated fat

Waxes Prevents water loss in plants


Earwax
Phospholipids found in cell
membranes
25
Saturated fatty acids have the
maximum number of hydrogens bonded
to the carbons (all single bonds
between carbons)
Unsaturated fatty acids have less than
the maximum number of hydrogens
bonded to the carbons (a double bond
between carbons)
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Single
Bonds in
Carbon
chain
Double bond in carbon chain
27

Composed of three fatty acids
bonded to a glycerol molecule
Figure 2.14a

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Body’s most efficient form for
storing large amounts of usable
energy
Found mainly beneath the skin and
around organs
Insulates deeper body tissues
from heat loss and protects from
trauma
Figure 2.14a

Women usually have a thicker
subcutaneous fatty layer (more
insulation) than men – why women are
more successful English Channel
swimmers

Most animal fats have a high proportion
of saturated fatty acids & exist as solids
at room temperature (butter, margarine,
shortening)
31

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Most plant oils tend to be low in
saturated fatty acids & exist as liquids at
room temperature (oils)
)
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•
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Cell membranes are made
of lipids called
phospholipids
Phospholipids have a head
that is polar & attract water
(hydrophilic)
Phospholipids also have 2
tails that are nonpolar and
do not attract water
(hydrophobic)
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
Phospholipids – modified
triglycerides with two fatty acid
groups and a phosphorus group
Figure 2.14b
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Amphipathic – has both polar and
nonpolar parts
Chief component of cell membranes
Nonpolar hydrocarbon portion (tail)
interacts with only other nonpolar
molecules
Phosphorus part is polar and
attracts polar or charged particles
like water and ions

Steroids – flat molecules with four
interlocking hydrocarbon rings
Figure 2.14c

Cholesterol is the structural basis
for all the body’s steroids
Found in cell membranes
 Raw material of vitamin D, bile salts,
sex hormones, and adrenal cortical
hormones.

 Estrogen & testosterone are steroids
Figure 2.14c
They
are variants of
testosterone
Some athletes use
them to build up
their muscles quickly
They can pose
serious health risks
38
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Eicosanoids – 20-carbon fatty acids
found in cell membranes – most
important is the prostaglandins which
has a role in blood clotting,
inflammation, and labor contractions
Fat-soluble vitamins – vitamins A, E,
and K
Lipoproteins which transport fatty
acids and cholesterol in the
bloodstream
Figure 2.14c
trans·lu·cent/transˈlo͞osnt/
Adjective: (of a substance)
Allowing light, but not detailed
images, to pass through;
semitransparent.

After discussing what proteins are
and looking at the molecular models
in the power point, students will be
able to identify proteins, state which
foods contain them, describe their
functions and state their building
blocks. Students will also be able to
explain the function of enzymes.



Basic structural material of the body
Other proteins play vital roles in cell
function
Proteins include
Enzymes
 Hemoglobin
 Contractile proteins of the muscle


All proteins contain carbon, oxygen,
hydrogen, and nitrogen, many contain
sulfur and phosphorus

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Amino acids are the building blocks
of protein,
 contains an amino group and a
carboxyl group
20 common types of amino acids
Figure 2.15a-c
Figure 2.15d, e
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Proteins are long chains of amino acids
joined together by dehydration
synthesis, resulting in a peptide bond
Most proteins are large molecules
containing from 100 to 10,000 amino
acids!
Figure 2.16
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Primary – amino acid sequence
Secondary – alpha helices or beta
pleated sheets
Tertiary – superimposed folding of
secondary structures
Quaternary – polypeptide chains
linked together in a specific manner
Figure 2.17a-c
Figure 2.17d, e

Fibrous proteins
 Extended and strandlike proteins
 Examples: keratin, elastin,
collagen, and certain contractile
fibers

Globular proteins
 Compact, spherical proteins with
tertiary and quaternary
structures
 Examples: antibodies, some
hormones, and enzymes

Reversible
unfolding of
proteins due
to drops in
pH and/or
increased
temperature
Figure 2.18a

Irreversibly denatured proteins
cannot refold and are formed by
extreme pH or temperature changes
Figure 2.18b
Changes in temperature & pH can
denature (unfold) a protein so it no
longer works
Cooking denatures
protein in eggs
Milk protein separates into
curds & whey when it
denatures
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Help other proteins to achieve
their functional three-dimensional
shape
Maintain folding integrity
Assist in translocation of proteins
across membranes
Promote the breakdown of
damaged or denatured proteins
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Most are globular proteins that act
as biological catalysts
Some enzymes are pure protein,
some have a cofactor, usually a metal
ion or an organic molecule derived
from vitamins
Enzymes are chemically specific
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Frequently named for the type of
reaction they catalyze
Enzyme names usually end in -ase
Lower activation energy

= energy needed to start a chemical
reaction
Figure 2.19

Enzyme binds with substrate


Product is formed at a lower
activation energy

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Substrate=reactants of an enzyme
catalyzed reaction
Product: compound produced by a
chemical reaction
Product is released
Active site
Amino acids
1
Enzyme (E)
Substrates (s)
H20
Enzymesubstrate
complex (E–S)
2
Free enzyme (E)
3
Peptide bond
Internal rearrangements
leading to catalysis
Dipeptide product (P)
Figure 2.20
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Blood sugar level is controlled by a
protein called insulin
Insulin causes the liver to uptake
and store excess sugar as Glycogen
The cell membrane also contains
proteins
Receptor proteins help cells
recognize other cells
63
INSULIN
Cell membrane with proteins &
phospholipids
64

After discussing what nucleic
acids are and looking at the
molecular models in the power
point, students will identify
them, their building blocks and
explain the importance of nucleic
acids in our bodies and how they
function.


Composed of carbon, oxygen,
hydrogen, nitrogen, and
phosphorus
Their structural unit, the
nucleotide, is composed of
Nitrogen-containing base, a
pentose sugar, and a phosphate
group
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Five nitrogen bases contribute to
nucleotide structure – adenine (A),
guanine (G), cytosine (C), thymine
(T), and uracil (U)
Two major classes – DNA and RNA
DNA has the bases A, G, C, &T.
RNA has the bases A, G, C, & U.

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Double-stranded helical molecule
found in the nucleus of the cell
Replicates itself before the cell
divides, ensuring genetic continuity
Provides instructions for protein
synthesis
Figure 2.21a
Figure 2.21b

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Single-stranded molecule found in
both the nucleus and the
cytoplasm of a cell
Uses the nitrogenous base uracil
instead of thymine
Three varieties of RNA:
messenger RNA, transfer RNA,
and ribosomal RNA


Source of immediately usable
energy for the cell
Adenine-containing RNA
nucleotide with three phosphate
groups
Figure 2.22
Figure 2.23
Lab next time.