Lecture 1: Key Molecules

Question 1

Describe fatty acids as an energy source

Answer 1

• carboxylic acid group on one end and methyl at the other
• long aliphatic chain between that can be saturated (C-C) or unsaturated (C=C)
• twice the energy of glucose per g

Question 2

Roles of fatty acids

Answer 2

• energy (fatty acids)
• structure (membrane lipids)
• signalling (steroid hormones)

Question 3

Draw phospholipid/membrane lipid

Question 4

Draw general structure of amino acids

Question 5

Describe general structure of amino acids

Answer 5

• altering the R chain alters the amino acid properties
• amino acid residues are linked by peptide bonds to form proteins
• primary structure folds into mature form of the protein

Question 6

Polarity of amino acids

Answer 6

Amine to carboxyl

Question 7

Polarity of DNA strands

Answer 7

• read from 5’ to 3’
• antiparallel

Question 8

How are phylogenetic trees built?

Answer 8

• comparison of partial ribosomal RNA data
• gene sequences conserved between organisms

Question 9

Carl Woese

Answer 9

• 1977
• discovered that archaea diverged from bacteria in early evolution