Lipids, Nucleic Acids

1
Chapter 2-3

• Lipids, Nucleic Acids Proteins

2
Four Groups of Organic Molecules

• Carbohydrates
• Lipids
• Protein
• Nucleic Acid

3
Lipids

• Made of mostly Carbon and Hydrogen
• Insoluble in water
• Three main categories fats, oils, waxes

4
Insolubility
5
(No Transcript)
6
(No Transcript)
7
Lipids Function

• Lipids are used to store energy
• What other organic compound is used to store
  energy?
• Carbohydrates- 4 calories/gram
• Fat- 9 calories/gram

8
Lipids Function

• Lipids are used to create biological membranes
• Membranes are the outer shells of animal cells
• Lipids form a protective barrier around the cell

9
Lipid Bilayer

• Membranes are created because of the unique shape
  of some lipids
• Certain lipids have a hydrophilic head
• and a hydrophobic tail

10
Lipid Bilayer

• When these lipids are put together, they create a
  lipid bilayer

11
(No Transcript)
12
(No Transcript)
13
How does detergent get greasy stains out?

• The structure of detergent is very similar to
  that of a lipid bilayer
• Detergent molecules with hydrophilic heads and
  hydrophobic tails surround grease/oil particles

14
How does detergent get greasy stains out?

• The hydrophobic tails surround grease/oil
  particle
• The hydrophilic heads interact with water
• The resulting structure is called a micelle
• The micelle is washed away with water, carrying
  the grease/oil particle with it!!

15
A Micelle
16
Fatty Acids

• Fatty acids- lipids built upon a glycerol
  backbone
• What is glycerol?

17
Fatty Acids

• When long chains of lipids join to glycerol, the
  resulting structure is called a fatty acid
• Fatty acids can be saturated- this means that
  each Carbon atom is connected to the maximum
  number of hydrogen atoms
• Fatty acids can be unsaturated-this means that
  some Carbon atoms are not connected to the
  maximum number hydrogen atoms

18
Fatty Acids
19
Fatty Acids

• Unsaturated fatty acids contain double bonds!!
• Fatty acids are the major component of cooking
  oils

20
Steroids

• Steroids- lipids with four carbon rings

21
Steroids

• The most important function of steroids is their
  role as hormones
• Examples testosterone, estrogen, aldosterone
• Another important steroid cholesterol

22
Nucleic Acids

• Macromolecules containing carbon, hydrogen,
  oxygen, nitrogen and phosphorus
• Composed of monomers called nucleotides

23
Nucleotides

• Nucleotides are the building blocks of nucleic
  acids
• There are four major nucleotides
• 1) Adenine
• 2) Thymine
• 3) Guanine
• 4) Cytosine

24
Nucleotides

• Nucleotides are composed of three major parts
• 1) a 5-carbon sugar
• 2) a phosphate group
• 3) a nitrogenous base
• Figure 2-15 on page 47

25
Nucleotides
26
Nucleic Acids Function

• Nucleic acids store and transmit heredity
• Nucleic acids are what make up the genetic code
• Two types of nucleic acids DNA (deoxyribonucleic
  acid) and RNA (ribonucleic acid)

27
DNA
28
DNA
29
Proteins

• Macromolecules that contain carbon, hydrogen,
  oxygen and nitrogen
• Composed of monomers called amino acids

30
Amino Acid

• The building blocks of proteins
• All amino acids contain an amino group
• (-NH2)
• All amino acids contain a carboxyl group
• (-COOH)
• Figure 2-16 on page 47

31
Amino Acid Structure
32
(No Transcript)
33
Amino Acids

• There are more than 20 amino acids!!
• The R group on each amino acid varies in size,
  shape, and chemical properties
• Amino acids combine to form the primary structure
  of a protein

34
Protein Structure

• Primary- amino acid chain forms
• Secondary- amino acids begins to twist and fold
• Tertiary- the chain begins to fold
• Quaternary- multiple chains twist into each
  other they are held together by Van der Waals
  forces

35
(No Transcript)
36
(No Transcript)
37
Protein Function

• Some proteins control the rate of chemical
  reactions within a cell (enzymes)

38
Protein Function

• Some proteins regulate cell what passes into and
  out of a cell (passive transport)

39
Protein Function

• Some proteins are used to provide structure for
  bone, muscle and other tissue