Week 2 & 3 MTC Notes
Essentials of Biochemistry
The ‘biological elements’
Water:
• Polar covalent bonds
o When a covalent bond is formed and there is an unsymmetrical distribution of
electron density (an unequal sharing of electrons)
• Hydrogen Bonding in H2O:
o Due to the polarity of water molecules, there is an electrostatic attraction
between molecules.
• Hydrophilic Molecules: are always either polar or ionic (charged) and therefore readily
dissolve in water.
• Hydrophobic Molecules: generally either contain non-polar bonds and are usually
insoluble in water. (eg. hydrocarbons)
• Hydrogen Ion Exchange: H+ ions can spontaneously move from one water molecule to
another, creating 2 ionic species: the hydronium ion (H3O+) and hydroxyl ion (OH-).
Weak Non-Covalent Bonds:
• Hydrogen bonds
• Hydrophobic Forces
• Ionic Bonds
• Van der Waals Forces
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, Basic Carbon Chemistry:
• Has 4 valence electrons
• Cannot form ionic bonds
o Rather, it forms covalent bonds through the sharing of its electrons.
• Has the ability to bond to either itself or four other atoms.
• May form chain, ring & branched structures.
chains:
• May form either single bonds (C-C), double bonds (C=C) or triple bonds (C=C).
• May form either saturated or non saturated molecules
o Saturated: contains the maximum number of Hydrogen atoms possible.
o Unsaturated: due to double/triple carbon bonds, there are less than the
maximum possible number of hydrogens.
C–O Compounds:
• Oxygen atoms in carbon-bonded molecules will always have 2 bonds (C=O or C-O-H) as
well as 2 unshared electron pairs.
• Functional groups:
www.MedStudentNotes.com
Essentials of Biochemistry
The ‘biological elements’
Water:
• Polar covalent bonds
o When a covalent bond is formed and there is an unsymmetrical distribution of
electron density (an unequal sharing of electrons)
• Hydrogen Bonding in H2O:
o Due to the polarity of water molecules, there is an electrostatic attraction
between molecules.
• Hydrophilic Molecules: are always either polar or ionic (charged) and therefore readily
dissolve in water.
• Hydrophobic Molecules: generally either contain non-polar bonds and are usually
insoluble in water. (eg. hydrocarbons)
• Hydrogen Ion Exchange: H+ ions can spontaneously move from one water molecule to
another, creating 2 ionic species: the hydronium ion (H3O+) and hydroxyl ion (OH-).
Weak Non-Covalent Bonds:
• Hydrogen bonds
• Hydrophobic Forces
• Ionic Bonds
• Van der Waals Forces
www.MedStudentNotes.com
, Basic Carbon Chemistry:
• Has 4 valence electrons
• Cannot form ionic bonds
o Rather, it forms covalent bonds through the sharing of its electrons.
• Has the ability to bond to either itself or four other atoms.
• May form chain, ring & branched structures.
chains:
• May form either single bonds (C-C), double bonds (C=C) or triple bonds (C=C).
• May form either saturated or non saturated molecules
o Saturated: contains the maximum number of Hydrogen atoms possible.
o Unsaturated: due to double/triple carbon bonds, there are less than the
maximum possible number of hydrogens.
C–O Compounds:
• Oxygen atoms in carbon-bonded molecules will always have 2 bonds (C=O or C-O-H) as
well as 2 unshared electron pairs.
• Functional groups:
www.MedStudentNotes.com
