Lecture 1 Feb 7

Question 1

What are the four Macromolecules?

Answer 1

Lipids, Proteins, Nucleic Acids, carbohydrates

Question 2

What is a covalent bond?

Answer 2

A strong chemical bond between atoms involving the sharing of one or more electrons

Question 3

What does a molecule’s valence refer to?

Answer 3

Bonding capacity

Question 4

What are macromolecules?

Answer 4

Molecules that include polymers made up of monomers

Question 5

What process facilitates the synthesis of polymers?

Answer 5

Dehydration because it removes a water molecule and forms a new bond

Question 6

What process breaks down polymers?

Answer 6

Hydrolysis, because it adds a water molecule and breaks a bond

Question 7

Examples of carbohydrates

Answer 7

Monomer:monosaccharide or simple sugar
Polymer:polysaccharide

Question 8

What are some facts about monosaccharides?

Answer 8

-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

Question 9

What is the right name for a six carbon and five carbon sugar?

Answer 9

Five carbon: Pentoses
Six Carbon: Hexoses

Question 10

What do glucose and other monosaccharides do in aqueous solutions?

Answer 10

They form rings to create the most stable compound

Question 11

What are the functions of monosaccharides?

Answer 11

Monomer for polysaccharides and fuel (catabolism)

Question 12

What are disaccharides?

Answer 12

joining of two monosaccharides with covalent bonds (glycosidic linkages)

Question 13

Examples of disaccharides

Answer 13

Sucrose, lactose, maltose

Question 14

What are polysaccharides?

Answer 14

multiple >2 monosaccharides with glycosidic linkages; function is storage and structure

Question 15

Examples of polysaccharides

Answer 15

Strach, glycogen, cellulose

Question 16

What is starch?

Answer 16

storage in plants, glucose monomers, surplus in starch granules, simplest form=amylose, 1-4 linkages; branches at 1-6 linkages

Question 17

What is glycogen?

Answer 17

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

Question 18

What is cellulose?

Answer 18

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

Question 19

How does polysaccharide digestion work?

Answer 19

Hydrolases of starch α linkages can’t hydrolyze β linkages in cellulose
* Cellulose = “insoluble fiber”
* Herbivore symbiotic relationship with bacteria

Question 20

Lipids

Answer 20

Unifying feature is hydrophobic with mostly hydrocarbon regions

Question 21

What are the three categories of lipids?

Answer 21

1. Steroids
2. Fats
3. Phospholipids

Question 22

Steroids

Answer 22

Carbon skeleton has 4 fused carbon rings; a component in animal cell membranes and a precursor for other steroids

Question 23

What is cholesterol?

Answer 23

a component in animal cell membranes and a precursor for other steroids; high cholesterol in blood may contribute to cardiovascular disease
HDL vs LDL

Question 24

What are fats?

Answer 24

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

Question 25

Fats are constructed of what two types of smaller molecules?

Answer 25

Glycerol and fatty acids

Question 26

What is glycerol?

Answer 26

3C alcohol with hydroxyl groups attached to each C

Question 27

What are fatty acids?

Answer 27

carboxyl group attached to a long carbon skeleton

Question 28

What are the two types of fats?

Answer 28

Saturated: no double bonds; saturated in hydrogen
Unsaturated: one or more double bonds; trans or cis

Question 29

Types of unsaturated

Answer 29

Polyunsaturated (>1 double bond) and monounsaturated (1 double bond)

Question 30

What are trans fats?

Answer 30

Fats with trans double bond

Question 31

What is hydrogenation?

Answer 31

Conversion of unsaturated fats to saturated fats by adding hydrogen

Question 32

Hydrophilic vs. hydrophobic

Answer 32

Hydrophilic: water-loving; polar charged molecules (ions, salts, alcohols, some proteins)
Hydrophobic: water fearing, non polar and no H bonding; oils and fats (fatty acids)

Question 33

What are phospholipids?

Answer 33

In water, self-assemble into double-layered sheets = phospholipid bilayers * At the cell surface
* Function: structure, semi-permeable barrier
a lipid containing a phosphate group in its molecule