ch6.4 - building blocks of life
TRANSCRIPT
The Building Blocks of Life
Chapter 6 Lesson 4
p.166-171
Vocabulary
• Macromolecule• Polymer• Carbohydrate• Lipid• Protein• Amino acid• Nucleic Acid• Nucleotide
Important Greek terms to make life easier
• Poly- = many
• Mono- = one
• Di- = two
• Meros- = part
Why study Carbon?
• All of life is built on carbon• Life on Earth is “carbon-based” • Cells
– ~72% H2O
– ~25% carbon compounds• carbohydrates• lipids• proteins • nucleic acids
– ~3% salts • Na, Cl, K…
Each carbon atom can make fourEach carbon atom can make fourcovalent bonds with other types of covalent bonds with other types of atoms or additional carbons.atoms or additional carbons.
Question: How many Question: How many electrons does carbon need electrons does carbon need to fill its outer energy level? to fill its outer energy level?
Answer: FourAnswer: Four
Chemistry of Life• Organic chemistry is the study of organic
compounds, or carbon compounds
• Carbon occurs so often in organic chemistry we don’t even need to put the atomic symbol.
MACROMOLECULES OF LIFE
• Found in all living things
• Building blocks of all cells• There are 4
1. Carbohydrates C, H, & O
2. Lipids C, H, & O
3. Proteins C, H, O, N, & S
4. Nucleic Acids C, H, O, N, & P
Macromolecules• Large molecules that are formed by joining
smaller organic molecules together.
Macromolecules
Monomers & Polymers• Macromolecules are actually made up of even
smaller subunits. Each subunit of a macromolecule is called a monomer.
• The macromolecules themselves are called polymers, because they are made up of many of these subunits.
Monomer: one basic unit or subunit
Polymer: a chain of many basic units
Biological Macromolecules
Carbohydrates Lipids Proteins Nucleic Acids
Carbohydrates
• (CH2O)n or C1:H2:O1 ratio
• n = number of CH2O units in a chain
Carbohydrates
Monosaccharide Disaccharide Polysaccharide
Monosaccharide
• (CH2O)3-7
• Simple sugars
• Function: Energy source for organisms– Example: glucose (C6H12O6)
Disaccharides
• 2 monosaccharide units linked together
Polysaccharides
• Long chains of monosaccharides
Lipids• Mostly made up of carbon and hydrogen
• Primary Function: energy storage• Include oils, fats, waxes, and steroids
Triglycerides
• Oils = if liquid at room temperature
• Fats = if solid at room temperature
Triglycerides
• Structure:– 3 Fatty Acids + Glycerol
• If the fatty acid tail only has single bonds between the carbon atoms, it is a saturated fat.– “Saturated” mean filled to maximum
capacity.
• If the fatty acid tail has one or more double bonds between the carbon atoms, it is an unsaturated fat.– Because the tail could make room,
accommodate, at least one more hydrogen.
• If the fatty acid tail has more than one double bond, you can call it a polyunsaturated fat.
Phospholipids
Phospholipids
• Special lipids that make up cell membranes.
• Like most lipids they are hydrophobic– Repels water– This makes for great barriers in the watery
environment of our cells
Other Lipids
• Waxes
• Steroids– Cholesterol – not all bad– Hormones – estrogen and testosterone
PROTEINS
• Monomer: amino acids
• Amino acids are small compounds that are made of carbon, nitrogen, oxygen, hydrogen, and sometimes sulfur.
• Function: enzymes, transport, and cell structure
Amino Acids
• Differ by R- unit or variable group
• There are 20 different variable groups
• So, there are 20 different amino acids
• Bonded by peptide bonds.• These form between one amino group
and one carboxyl group
Protein structure
• Proteins, amino acid chains, can be any length and any combination.
• They have four levels of structure.
Primary (1°)
• Number and order of amino acids in a chain
Secondary (2°)
• Hydrogen bonds between different amino acids cause the chain to fold
• They can form shapes like a helix, pleated sheet, or fold
Tertiary Structure (3°)
• The full structure of the protein with can include many 2° structures.
• And they look really cool!
Quaternary Structure (4°)
• Not all proteins have a 4° structure.
• The combination of proteins that work together as one.
Protein Function
• Proteins are ~15% of your total body mass• Involved in almost every function:
– Muscles, skin, hair
– Cellular communication
– Enzymes
– Control cell growth– Protection (immunity)– Storage
• Our cells contain over 10,000 different proteins
Nucleic Acids
• Function: store and transmit genetic information
• Monomer: nucleotides– Nucleotides are composed of C, N, O, P, H
• There are 5 major nucleotides– The book says 6, because it includes ATP
(wrong)
• The sugar of one nucleotide bonds to the phosphate of another nucleotide
• The nitrogenous base sticks out to form hydrogen bonds that hold the double helix together.
Types of nucleic acids
Adenosine Triphosphate (ATP)
• A modified nucleotide
• 3 phosphate groups
