Transcript 2.3 Carbon based molecules powerpoint mod

2.3 Carbon-Based Molecules
• Objective:
SWBAT: Summarize the Characteristics of
organic compounds
IOT: Identify the function and structure of
biomolecules
2.3 Carbon-Based Molecules
KEY CONCEPT
Carbon-based molecules are the foundation of life.
Meaning all living things are based on carbon-based
molecules.
2.3 Carbon-Based Molecules
Carbon atoms have unique bonding properties.
• Carbon atoms form stable bonds with four other atoms
(Hydrogen, Oxygen, Nitrogen and/or Carbon), this makes it
suited for the construction of complex molecules.
• Chemically, this is due to carbons 4 valence electrons
which make it able to form 4 bonds to achieve stability.
Valence electrons – electrons in the outermost energy level;
these are the electrons that are available to bond with other
atoms
2.3 Carbon-Based Molecules
• Many carbon-based molecules are made of many small
subunits bonded together called monomers.
– Monomers join together to form a polymer.
• Assembling & Disassembling Polymers via Chemical
Reactions
– Hydrolysis- water interacts with a polymer breaking
the bonds that link monomers to each other.
Break a polymer down into monomers
– Dehydration synthesis- bonds are formed linking
monomers together while losing water molecules.
Build a polymer by bonded a bunch of monomers
2.3 Carbon-Based Molecules
Four main types of carbon-based molecules are found in
living things.
1. Carbohydrates
• Chemical Make-up
Carbohydrates are made of C, H, and O
in a 1:2:1 ratio
• Monomer/Polymer
– Monomer: Monosaccharides
– Polymer: Polysaccharides
2.3 Carbon-Based Molecules
• Functions
Carbohydrates can be broken down to provide energy for
cells.
Some carbohydrates are part of cell structure.
• Example
Carbohydrates include sugars, cellulose, starches
Polymer (starch)
Polymer (cellulose)
monomer
Starch is a
polymer of
glucose
monomers that
often has a
branched
structure.
Cellulose is a
polymer of
glucose
monomers that
has a straight,
rigid structure
2.3 Carbon-Based Molecules
2. Lipids
• Chemical Make-up
Composed of C, H and a little O
• Monomer/Polymer
– Monomer: Fatty acids bonded to glycerol
– Polymer: Lipids
• Examples
Triglycerides (fats, oils) phospholipids, steroids (cholesterol,
hormones) and wax.
Triglyceride
2.3 Carbon-Based Molecules
• Fats and oils have different types of fatty acids.
– saturated fatty acids
– unsaturated fatty acids
Chemical Structure
2.3 Carbon-Based Molecules
• Saturated versus Unsaturated fats
Saturated fats butter, dairy products, meat- which remains
solid at room temperature.
–“Bad” because in excess raise cholesterol
–Saturated or full- no more hydrogen (or other atoms) can be
added
Unsaturated fats avocado, soybean oil, canola oil and olive
oil.
–“Good”
–Unsaturated or not full- More hydrogen can be added
2.3 Carbon-Based Molecules
• Functions
Lipids have several different functions.
– broken down as a source of energy
– make up cell membranes
– used to make hormones- control important body functions
2.3 Carbon-Based Molecules
3. Proteins
• Chemical Make-up
Made up of C, H, O, S and N
• Monomer/Polymers
– Monomer: Amino acids (Twenty different amino acids are
used to build proteins in organisms.)
– Polymer: Polypeptides or Proteins (bunch of amino acids)
R group
Amino group
Carboxyl
2.3 Carbon-Based Molecules
• Examples
- Can be found in foods like beans, nuts and meat
- Enzymes
- Hormones
• Functions
- Different proteins have different functions
- Major functions include structural support,
- Speed up chemical reactions (enzymes)
- Communication via hormones
2.3 Carbon-Based Molecules
Nucleic acids
• Make-up
Made up of C, H, O, P and N
• Monomer/Polymer
– Nucleotides (are made of a sugar, phosphate group,
and a nitrogen base.)
– Nucleic acids
A phosphate group
deoxyribose (sugar)
nitrogen-containing
molecule,
called a base
2.3 Carbon-Based Molecules
Examples
– DNA deoxyribose nucleic acid
– RNA ribonucleic acid
DNA
Functions
– DNA stores genetic information;
holds instructions for controlling
EVERYTHING that happens in a
cell.
RNA
– RNA builds proteins