Lec 2 Flashcards
(13 cards)
What are the four major types of organic compounds found in living cells?
Carbohydrates, Lipids, Proteins and Nucleic Acids
What determines the polarity of a covalent bond?
The difference in electronegativity between the atoms in the bond.
What is the difference between hydrophilic and hydrophobic compounds?
Hydrophilic compounds are water-soluble (polar), while hydrophobic compounds are not (non-polar).
What type of reaction forms polymers from monomers, and what molecule is released?
Condensation (dehydration) reaction; water (H2O).
What type of reaction breaks down polymers into monomers, and what molecule is required?
Hydrolysis; water (H2O).
What is the general formula for carbohydrates?
Cn(H2O)n
Name the four categories of biologically important carbohydrates.
Monosaccharides, Disaccharides, Oligosaccharides, and Polysaccharides
What is the difference between isomers and epimers?
Isomers have the same chemical formula but different arrangements of atoms. Epimers differ in the position of the hydroxyl group at only one asymmetric carbon.
What is a glycosidic linkage?
A covalent bond that joins two monosaccharides.
What is a polar bond?
A polar bond occurs when atoms in the bond have very different electronegativities, resulting in unequal sharing of electrons.
What is the difference between α- and β-glucose?
They are ring forms of glucose that differ in the position of the hydroxyl group on the anomeric carbon.
What is a glycosidic bond?
A bond formed when the -OH group on the anomeric carbon of one sugar reacts with an -OH group of another sugar.
What are the main differences between starch, glycogen, and cellulose?
Starch (plants) and glycogen (animals) are branched polymers of glucose with α-1,4 and α-1,6 glycosidic linkages
- Cellulose is an unbranched polymer of glucose with β-1,4 glycosidic linkages
