Lecture 1 Feb 7 Flashcards
What are the four Macromolecules?
Lipids, Proteins, Nucleic Acids, carbohydrates
What is a covalent bond?
A strong chemical bond between atoms involving the sharing of one or more electrons
What does a molecule’s valence refer to?
Bonding capacity
What are macromolecules?
Molecules that include polymers made up of monomers
What process facilitates the synthesis of polymers?
Dehydration because it removes a water molecule and forms a new bond
What process breaks down polymers?
Hydrolysis, because it adds a water molecule and breaks a bond
Examples of carbohydrates
Monomer:monosaccharide or simple sugar
Polymer:polysaccharide
What are some facts about monosaccharides?
-Molecular formula usually have a general formula of CH2O
-Characterized by multiple hydroxyl groups
-Glucose is most common C6H12O6
-Classified by: location of the carbonyl group (aldose or ketone); the number of carbons in skeleton
What is the right name for a six carbon and five carbon sugar?
Five carbon: Pentoses
Six Carbon: Hexoses
What do glucose and other monosaccharides do in aqueous solutions?
They form rings to create the most stable compound
What are the functions of monosaccharides?
Monomer for polysaccharides and fuel (catabolism)
What are disaccharides?
joining of two monosaccharides with covalent bonds (glycosidic linkages)
Examples of disaccharides
Sucrose, lactose, maltose
What are polysaccharides?
multiple >2 monosaccharides with glycosidic linkages; function is storage and structure
Examples of polysaccharides
Strach, glycogen, cellulose
What is starch?
storage in plants, glucose monomers, surplus in starch granules, simplest form=amylose, 1-4 linkages; branches at 1-6 linkages
What is glycogen?
Storage in animals, glucose monomers, stored mainly in liver and muscle cells, Hydrolysis releases glucose when demand for sugar increases, 1-4 linkages and branches 1-6 linkages
What is cellulose?
Major component of cell wall, glucose monomer, glycosidic linkages differ: only 1-4 linkages, and based on two ring forms for glucose: alpha and beta
How does polysaccharide digestion work?
Hydrolases of starch α linkages can’t hydrolyze β linkages in cellulose
* Cellulose = “insoluble fiber”
* Herbivore symbiotic relationship with bacteria
Lipids
Unifying feature is hydrophobic with mostly hydrocarbon regions
What are the three categories of lipids?
- Steroids
- Fats
- Phospholipids
Steroids
Carbon skeleton has 4 fused carbon rings; a component in animal cell membranes and a precursor for other steroids
What is cholesterol?
a component in animal cell membranes and a precursor for other steroids; high cholesterol in blood may contribute to cardiovascular disease
HDL vs LDL
What are fats?
Major function is energy storage, humans and other mammals store long-term food reserves in adipose cells, adipose tissues also cushion vital organs and insulate body; fat= triglyceride or triacylglycerol
