Course 3 Cell Biology
BIOMOLECULES 2
DNA 4
REPLICATION 5
TRANSCRIPTION 6
TRANSLATION 7
MUTATIONS 8
HAN University of Applied Sciences, Nijmegen, The Netherlands
Bachelor of Life Sciences
Propaedeutic Year
Course 3: Molecular Biological research on DNA and Proteins
Notes by Melchior Philips (http://melch.io/r)
, Biomolecules
Biomolecules are molecules that are present and synthesised in biological systems.
Carbohydrates
Carbohydrates (polysaccharides) are a polymer of sugars (monosaccharides).
Carbohydrates are polymerized by means of dehydration synthesis, and are digested by
means of hydrolysis.
o Every link produces 1 H2O molecule when formed, and costs 1 H2O molecule to
break.
Sugars can vary in three different ways:
o Number of C-Atoms (Triose, Tetrose, Pentose, Hexose)
o Position of Carbonyl Group
If it's at the end, it's an Aldose.
If it's in the middle, it's a Ketose.
o Spatial arrangement around asymmetric carbons
Basically on what side of the carbon backbone the hydroxyl group is located.
o There are also deoxy sugars, which are variations of the same sugar with one oxygen
atom less.
e.g. Deoxyribose vs. Ribose
Sugars can have an α and β arrangement, also known as trans- and cis- respectively.
o On a cis arrangment, the hydroxyl group at the final carbon is on the same side of
the sugar molecule as the hydroxyl group on the 1-carbon. With trans it is on the
other side.
o Starch is a polymer of α-Glucose. It can be digested by humans.
o Cellulose is a polymer of β-Glucose. It cannot be digested by humans.
Lipids
Lipids store energy. More efficiently so than saccharides.
Lipids are a polymer of fatty acids, bound together with ester linkages.
Lipids can be saturated or unsaturated.
o Saturated fats have only single bonds
o Unsaturated fats have one or more double bonds, causing the molecule to bend and
take up more space.
Cis-unsaturated fats have a double bond where both hydrogens are at the
same side of the double bond.
Trans-saturated fats have a double bond where the hydrogens are at
different sides of the double bond.
Phospholipids are amphipathic; they are both hydrophilic and hydrophobic.
o The head is hydrophilic and consists of Choline, a Phosphate and a Glycerol.
o The tail is hydrophobic and consists of two fatty acids.
Cholesterol is a hormone, and thusly a lipid. In the cell membrane it reduces fluidity of the
membrane (increases viscosity), and hinders solidification (freezing) of the cell membrane at
low temperatures.
Course 3 Chemistry page 2 http://melch.io/r
BIOMOLECULES 2
DNA 4
REPLICATION 5
TRANSCRIPTION 6
TRANSLATION 7
MUTATIONS 8
HAN University of Applied Sciences, Nijmegen, The Netherlands
Bachelor of Life Sciences
Propaedeutic Year
Course 3: Molecular Biological research on DNA and Proteins
Notes by Melchior Philips (http://melch.io/r)
, Biomolecules
Biomolecules are molecules that are present and synthesised in biological systems.
Carbohydrates
Carbohydrates (polysaccharides) are a polymer of sugars (monosaccharides).
Carbohydrates are polymerized by means of dehydration synthesis, and are digested by
means of hydrolysis.
o Every link produces 1 H2O molecule when formed, and costs 1 H2O molecule to
break.
Sugars can vary in three different ways:
o Number of C-Atoms (Triose, Tetrose, Pentose, Hexose)
o Position of Carbonyl Group
If it's at the end, it's an Aldose.
If it's in the middle, it's a Ketose.
o Spatial arrangement around asymmetric carbons
Basically on what side of the carbon backbone the hydroxyl group is located.
o There are also deoxy sugars, which are variations of the same sugar with one oxygen
atom less.
e.g. Deoxyribose vs. Ribose
Sugars can have an α and β arrangement, also known as trans- and cis- respectively.
o On a cis arrangment, the hydroxyl group at the final carbon is on the same side of
the sugar molecule as the hydroxyl group on the 1-carbon. With trans it is on the
other side.
o Starch is a polymer of α-Glucose. It can be digested by humans.
o Cellulose is a polymer of β-Glucose. It cannot be digested by humans.
Lipids
Lipids store energy. More efficiently so than saccharides.
Lipids are a polymer of fatty acids, bound together with ester linkages.
Lipids can be saturated or unsaturated.
o Saturated fats have only single bonds
o Unsaturated fats have one or more double bonds, causing the molecule to bend and
take up more space.
Cis-unsaturated fats have a double bond where both hydrogens are at the
same side of the double bond.
Trans-saturated fats have a double bond where the hydrogens are at
different sides of the double bond.
Phospholipids are amphipathic; they are both hydrophilic and hydrophobic.
o The head is hydrophilic and consists of Choline, a Phosphate and a Glycerol.
o The tail is hydrophobic and consists of two fatty acids.
Cholesterol is a hormone, and thusly a lipid. In the cell membrane it reduces fluidity of the
membrane (increases viscosity), and hinders solidification (freezing) of the cell membrane at
low temperatures.
Course 3 Chemistry page 2 http://melch.io/r
