Download Topic 2: Molecular Biology

Topic 2: Molecular Biology
2.1 Molecules to Metabolism
Essential Idea: Living Organisms control their composition by complex web of chemical reactions.
U1 Molecular biology explains living processes in terms of the chemical substances involved
U2 Carbon atoms can form four covalent bonds allowing a diversity of stable compounds to exist
U3 Life is based on carbon compounds including carbohydrates, lipids proteins and nucleic acids
U 4Metabolism is the web of all the enzyme-catalyzed reactions in a cell or organism
U5 Anabolism is the synthesis of complex molecules from simpler molecules including the formation of macromolecules
from monomers by condensation reactions
U6 Catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of
macromolecules into monomers
A1 Urea as an example of a compound that is produced by living organisms but can also be artificially synthesized
S1 Drawing molecular diagrams of glucose, ribose, a saturated fatty acid and a generalized amino acid
S2 Identification of biochemical such as sugars, lipids, or amino acids from molecular drawings
NOS1 Falsification of theories- the artificial synthesis of urea helped to falsify vitalism.
2.2 Water
Essential Idea: Water is the medium of life.
U1 Water molecules are polar and hydrogen bonds form between them.
U2 Hydrogen bonding and dipolarity explain the cohesive, adhesive, thermal and solvent properties of water.
U3 Substances can be hydrophilic or hydrophobic.
A1 Comparison of the thermal properties of water with those of methane.
A2 Use of water as a coolant in sweat.
A3 Modes of transport of glucose, amino acids, cholesterol, fats. Oxygen, and sodium in blood in relations to their
solubility in water.
NOS1 Use of theories to explain natural phenomena- the theory that hydrogen bonds form between water molecules
explain the properties of water.
2.3 Carbohydrates and Lipids
Essential Idea: Compounds of carbon, hydrogen and oxygen are used to supply and store energy.
U1 Monosaccharide monomers are linked together by condensation reactions to form disaccharides and polysaccharide
polymers.
U2 Fatty acids can be saturated, monounsaturated and polyunsaturated.
U3 Unsaturated fatty acids can be cis or trans isomers.
U4 Triglycerides are formed by condensation from three fatty acids and one glycerol.
A1 Structure and function of cellulose and starch in plants and glycogen in humans.
A2 Scientific evidence for health risks of trans fat and saturated fatty acids.
A3 Lipids are more suitable for long term energy storage in humans than carbohydrates.
A4 Evaluation of evidence and the methods used to obtain the evidence for health claims made about lipids.
S1 Use of molecular visualization software to compare cellulose, starch and glycogen.
S2 Determination of body mass index by calculation or use of a nomogram.
NOS1 Evaluating claims- health claims made about lipids in diets need to be assessed.
2.1 Molecules to metabolism
Please review p. 62-67 in the Oxford IB Text, p. 34-43 in the Campbell text and p. 51 in your Biozone.
1. Drawing molecular diagrams of glucose, ribose, a saturated fatty acid and a generalized amino acid
Molecule
name
Ribose
Formula
C5H10O5
Directions




Glucose
C6H12O6




Saturated
fatty acids
X





Amino
Acids
X


5-membered ring with a side chain
4 C are in the right and one forms the
side chain
# the 5 Cs starting with number 1 on
the right
The hydroxyl groups (OH) on carbon
atoms 1, 2, 3 point up, down, and
down respectively
6-membered ring with a side chain
5 C atoms are in the ring and one
forms side chain
The C atoms can be # starting with
number 1 on the right
The hydroxyl groups (OH) on carbon
atoms 1,2,3,4 point down, down, up
and down respectively
C atoms form an unbranched chain
Bonded by single bonds
# of C atoms usually between 14-20
At one end of chain the C atom is
part of a carboxyl group
At the other end the C atom is
bonded to 3 H atoms
All other Cs are bonded by 2 H atoms
A C atom in the center is bonded to 4
things:
*Amine group
* Carboxyl group
*H atom
*the R group
2. Define and explain condensation reactions
3. Define and explain metabolism, anabolism, and catabolism.
Diagram
2.2 Water
Please review p. 68-73 in the Oxford IB Text, p. 25-26 in the Campbell text and p. 52-53 in your Biozone.
1. Draw and annotate TWO bonded water molecules below. Include annotations of: polarity (negative and
positive poles), and covalent/hydrogen bonds Remember: Biological drawings need strong clear lines, accurate
shapes, neat labeling & no shading
Water molecules:
2. Fill out the table below on the properties of water
Properties of Water
Cohesive properties
Description
Adhesive properties
Thermal properties:
 High specific
heat capacity
 High latent
heat of
vaporization
 High boiling
point
Solvent properties
3. Explain how substances can be hydrophilic or hydrophobic.
How it is useful to living organisms
(Transpiration)
(Transpiration)
(Transport in blood plasma: sodium chloride, amino acids,
glucose, oxygen, fat molecules, and cholesterol)
2.3 Carbohydrates and lipids
Please review p. 73-86 in the Oxford IB Text, p. 36-41in the Campbell text and p. 54-61 in your Biozone.
1. Monosaccharides monomers are linked together by condensation reactions to form disaccharides and
polysaccharide polymers. Glucose, fructose and ribose are all examples of monosaccharides. Describe each
of the following and INCLUDE EXAMPLES OF EACH:
a. Monosaccharides:
b. Disaccharides:
c. Polysaccharides:
2. Label the process next to each arrow either condensation or hydrolysis.
3. What is the difference between a saturated, a monounsaturated and a polyunsaturated fatty acids in regards
to their covalent bonds?
Type of fatty acid
Description of bonds
Diagram
Saturated
Monounsaturated
Polyunsaturated
4. What is the difference between a cis and a trans fatty acid? Draw two pictures for comparison.
Unsaturated fatty
Description of bonds
Diagram
acid
Cis
trans
5. What are some of the health issues related to fatty acids?