Download LS50 Section 02 Slides

(Biomolecules)
Nucleic acids
Carbohydrates
Lipids
Proteins
Slide logic:
1.
What elements do they use?
2.
What are the monomers?
3.
What are the functional groups?
4.
How are the monomers linked?
5.
What is the function of the molecule?
Images from: http://blog.science-matters.org/2012/01/23/the-four-major-classes-of-biomolecules/
Carbohydrates
Carbohydrates
Function
Energy and structure
What are the elements that make up carbohydrates?
How are carbohydrates linked together?
Elements: C,H,O
Cells build carbohydrate polymers by
using energy to form glycosidic linkages.
What are the building blocks (monomers) of carbohydrates?
Long chains with hundreds of monosaccharides
are called polysaccharides and are usually made
of one type of monosaccraride
Monomers: Monosaccharides with general formula (CH2O)n, where n is at least 3
Which are the functional groups?
Carbonyl
These are diastereomers,
which have different taste and
chemical reactivity
Hydroxyl
glycogen:
energy storage
cellulose:
structure
chitin: structure
Nucleic acids: DNA & RNA
Nucleic acids: DNA & RNA
How are nucleotides linked to form nucleic acids? (Nucleotide polymerization)
What are the elements that make up nucleic acids?
Elements: C,H,O,P,N
Nucleic acids are
synthesized from 5’ to 3’
phosphodiester bond
What are the building blocks (monomers) of nucleic acids?
Monomer: nucleotide (5 carbon sugar, phosphate group, nitrogenous base - A,T,C,G,U)
Function
Store & transmit hereditary information
What are these?
How do they come together?
How do nucleotides pair?
phosphate
nitrogenous base
sugar
Adenine
hydrogen bonding underlies base-pairing
Digression: ATP Information is transferred
by base-pairing
Lipids
(nucleotides have other functions)
What are the elements that make up lipids?
Energy currency
of the cell!
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clea
Elements: C,H,O,P
What are the building blocks (monomers) of lipids?
Monomers: glycerol, fatty acids (some of the classes of lipids)
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av
Which are the functional groups?
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Hydroxyl
Unit of information
transmission
Adenine
Carboxyl
Lipids
Proteins
How are monomers linked in lipids?
What are the elements that make up proteins?
Function
nonpolar
Energy storage (fats)
Chemical signaling (steroids)
Structure (phospholipids)
Elements: C,H,O,N,S
What are the building blocks (monomers) of proteins?
Monomers: amino acids (20 of these)
Which are the functional groups?
What is the difference?
R is the side-chain (amino acid identity)
hydrophobic tail
Amine
Carboxyl
hydrophilic head
Proteins
Proteins
How are amino acids linked to form proteins?
How are amino acids linked to form proteins?
1. Primary structure
2. Secondary structure
Linear sequence of amino acids in the polypeptide chain: the amino acids are joined together by covalent
peptide bonds
Peptide bond
rotation possible
rotation restricted
The peptide bond is a hybrid between the two resonance structures,
so all six atoms lie in the same plane
The amino acids arrange in space to maximize the number of hydrogen bonds
between the amide hydrogen N-H and the carboxyl oxygen
Proteins
Check these out:
How are amino acids linked to form proteins?
http://learn.genetics.utah.edu/content/molecules/builddna/
If you play around with this for a bit you will appreciate hydrogen bonding and (if you try to build the DNA as fast as you can)
the speed and accuracy of DNA polymerase. You can also get a feeling for how nucleotides fit together to form the double
helix (i.e. how many nucleotides are there per helix period?)
3. Tertiary structure
The final 3D structure of proteins, mostly driven by entropy
https://dlc.dcccd.edu/biology1-3
Overview of the four major classes of biomolecules (and source for a lot of the images in the slides). It has nifty animated
exercises for identifying functional groups and linking molecules together, you should try them out for practice.
https://www.youtube.com/watch?v=tk-SNvCPLCE
https://www.youtube.com/watch?v=457xnJv80O0
Nice (and brief) visualization of chirality, diastereomers, enantiomers …
Function
Structure
Transport
Defense
Enzymes