biological molecules
DESCRIPTION
Biological molecules. Carbohydrates, Lipids, Proteins, and Nucleic Acids. Is it made of carbohydrates?. Carbohydrates. Carbohydrates. Organic compounds composed of carbon, hydrogen, and oxygen in a 1:2:1 ratio. A carbohydrate with 6 carbon atoms would have… - PowerPoint PPT PresentationTRANSCRIPT
BIOLOGICAL MOLECULES
Carbohydrates, Lipids, Proteins, and Nucleic Acids
Is it made of carbohydrates?
CARBOHYDRATES
CARBOHYDRATES Organic compounds composed of carbon,
hydrogen, and oxygen in a 1:2:1 ratio.A carbohydrate with 6 carbon atoms would
have…
______ hydrogen atoms and ______ oxygen atoms 12 6
Source of ENERGY
Structural components of cells
MONOSACCHARIDES Monomer of carbohydrate (simple
sugar)
Most have 6 carbon atoms
Most common:1) Glucose (main source of energy)
2) Fructose (found in fruits)
3) Galactose (found in milk)
ISOMERS
Glucose, fructose, and galactose have the same chemical formula.
C6H12O6
Same formula but different structural forms.
DISACCHARIDES AND POLYSACCHARIDES Disaccharide: two monosaccharides
bond to form a double sugar.Example: sucrose
Polysaccharide: complex molecule composed of three or more monosaccharides.
POLYSACCHARIDES IN ANIMALS AND PLANTS Glycogen: animals store glucose in the
form of the large, complex molecule – glycogen
Starch: plants store glucose molecules in the form of starch.
Cellulose: large polysaccharide made by plants, which provide strength and rigidity to plant cells.
WHITE VS. WHOLE GRAIN
WHITE VS. WHOLE GRAIN
White bread is a simple carbohydrate (little nutritional value, digested more quickly, converted to fat more quickly)
Whole grain bread is a complex carbohydrate (high in fiber, vitamins and minerals, provide more energy, digested slowly)
LIPIDS
LIPIDS Large organic molecules
Nonpolar – do NOT dissolve in water
Include phospholipids, triglycerides, waxes, steroids
Higher ratio of carbon and hydrogen to oxygen than carbohydrates…. More C-H bonds
Store more energy per gram than most other organic compounds
FATTY ACIDS
Hydrocarbon End
C-HNonpolar
Hydrophobic
Carboxyl End-COOHPolar
Hydrophilic
Saturated: Each carbon atom is single-bonded to 4 other atoms; straight chain; molecules are close together; solid at room temperature
Unsaturated: Double bonds in the C chain; kinked chain; molecules are farther apart; liquid at room temperature
TYPES OF FATTY ACIDS: SATURATED VS UNSATURATED http://www.youtube.com/watch?v=
ESPNqKUluRs
Let’s list some more differences in the form and function of fatty acids
TYPES OF LIPIDS MADE OF FATTY ACIDSTriglycerides (FATS)
3 fatty acids molecules joined to 1 glycerol
Saturated triglycerides are composed of saturated fatty acids (butter, other dairy products, fat from red meat)
Unsaturated triglycerides are composed of unsaturated fatty acids (mostly found oils and in plant seeds)
TYPES OF LIPIDS MADE OF FATTY ACIDS
Phospholipids
Glycerol is connected to 2 fatty acid molecules and a phosphate group.
The plasma membrane of the animal and plant cells are composed of a phospholipid bilayer.
TYPES OF LIPIDS MADE OF FATTY ACIDSWaxes
Composed of a long fatty acid chain and a long alcohol chain.
Waterproof and provide protection.
Found on the surface of plants and in the ear canals of many animals (including humans).
STEROIDS NOT composed of fatty acids
Four fused carbon rings which are attached to other functional groups
Cholesterol (found in the cell and plasma membrane)
Hormones such as testosterone and estrogen
PROTEINS
Is it made of Proteins?
PROTEINS ~ WHAT ARE THEY? Organic molecules compose of
hydrogen, carbon, oxygen and NITROGEN
Monomers = AMINO ACIDS
Examples: HairHornsSkinMusclesENZYMES (to learn more about later!)
AMINO ACIDS (AA) 20 different AA
Central carbon, C, that is covalently bonded to 4 other groups1. Hydrogen = blue2. Carboxyl (-COOH) = green3. Amine (-NH2) = yellow4. R group = red (varies in each AA and
determines the AA’s form and function
AA can also be illustrated as a ball
DIPEPTIDES AND POLYPEPTIDES
Dipeptide: two amino acids bond Polypeptides: long chains of amino acids
(made up of 1 or more dipeptide) Making proteins: what builds them?
Reaction: condensation or hydrolysis
Water is released or used
DIPEPTIDES AND POLYPEPTIDES Some proteins are very large, some are
small. Protein shape:
Influences its function (form and function)Shape can be influenced by factors like
temperature and solvent) … for example, egg white is clear when it is uncooked, and white when it is cooked
ENZYMES RNA or protein molecules that act as
biological catalystsCatalyst – speeds up the reaction by
lowering the activation energy Essential for cellular function Each Enzyme bonds with a specific
Substrate for form the Active Site
HOW DO ENZYMES WORK Speed up reactions – how????
Enzyme bonds to substrate and the enzyme shape changed slightly
The chemical bonds in the substrate are weakened
Lowers the activation energy
What happens after the reaction? Enzyme releases the products Enzyme is unchanged…
BUT changes in temperature and pH can change the enzyme (denature it) and it may not function properly or at all
NUCLEIC ACIDS
NUCLEIC ACIDS ~ SOURCE OF THE INFORMATION Large and complex biological molecules
Store and transfer important information in the cell
Genetic Code
Two types – both are polymers 1. DNA - DeoxyriboNucleic Acid 2. RNA - RiboNucleic Acid
DNA is transcribed into RNA, which is translated into PROTEINS
NUCLEIC ACIDS ~ STRUCTURE Each nucleotide is made of:
a phosphate group, a five carbon sugar, and a ring-shaped nitrogen base
Nitrogen basesA - AdenineC – CytosineG – GuanineT – ThymineU - uracil