Chapter 7

Question 1

What are macronutrients?

Answer 1

Nutrients that the body needs in large amounts for growth, energy, and health.
- Carbohydrates, protein, and fat

Question 2

What are micronutrients?

Answer 2

Nutrients required for the body to function properly.
- Vitamins and minerals

Question 3

Organic molecules versus inorganic molecules

Answer 3

Organic - contain carbon
Inorganic - no carbon

Question 4

What are isomers?

Answer 4

Different arrangements of the same molecule.

Question 5

What are enantiomers?

Answer 5

Enantiomers are molecules that have the characteristic of chirality, in which their structures are nonsuperimposable mirror images of each other.

Question 6

What are macromolecules?

Answer 6

Polymers assembled from individual units (monomers) which bind together like building blocks.

Question 7

How are macromolecules formed?

Answer 7

Dehydration synthesis

Question 8

What is dehydration synthesis?

Answer 8

A process in which monomers bind together by combining their functional groups and generating water molecules as byproducts.

Question 9

What are carbohydrates used for?

Answer 9

Widely used for structural and energy-storage purposes.

Question 10

What are monosaccharides?

Answer 10

Individual sugar molecules

Question 11

How are monosaccharides classified?

Answer 11

Based on their number of carbons.
3C - trioses
4C - tetroses
5C - pentoses
6C - hexoses

Question 12

What are disaccharides?

Answer 12

Molecules composed of two monosaccharides linked together by a glycosidic bond.
Ex. sucrose, lactose, and maltose

Question 13

What are polysaccharides?

Answer 13

Polymers composed of hundreds of monosaccharide monomers linked together by glycosidic bonds.

Question 14

What are the three most biologically important polysaccharides?

Answer 14

Starch, glycogen, and cellulose

Question 15

What is the primary energy-storage molecule in animals and bacteria?

Answer 15

Glycogen

Question 16

What is the primary energy-storage molecule in plants?

Answer 16

Starch

Question 17

What are lipids composed of?

Answer 17

Mainly of carbon and hydrogen, but they can also contain oxygen, nitrogen, sulfur, and phosphorous.

Question 18

What do lipids do?

Answer 18

They provide nutrients for organisms, store carbon and energy, play structural roles in membranes, and function as hormones, pharmaceuticals, fragrances, and pigments.

Question 19

What are fatty acids?

Answer 19

Long-chain hydrocarbons with a carboxylic acid functional group. Their relatively long nonpolar hydrocarbon chains make them hydrophobic.

Question 20

What makes a fatty acid saturated versus unsaturated?

Answer 20

Saturated has no double bonds.
Unsaturated has double bonds.

Question 21

What are biological membranes?

Answer 21

Large-scale structures based on phospholipid bilayers that provide hydrophilic exterior and interior surfaces suitable for aqueous environments, separated by an intervening hydrophobic layer.

Question 22

What is a wax?

Answer 22

A long-chain isoprenoid that is typically water resistant.

Question 23

What are steroids?

Answer 23

Lipids with complex, ringed structures that function as structural components of cell membranes and as hormones.

Question 24

What are amino acids?

Answer 24

Amino acids are small molecules essential to all life.

Question 25

What are the parts of an amino acid?

Answer 25

Each has an α carbon to which a hydrogen atom, carboxyl group, and amine group are bonded. The fourth bonded group, represented by R, varies in chemical composition, size, polarity, and charge among different amino acids, providing variation in properties.

Question 26

What are peptides?

Answer 26

Peptides are polymers formed by the linkage of amino acids via dehydration synthesis. The bonds between the linked amino acids are called peptide bonds.

Question 27

What are proteins?

Answer 27

Proteins are polymers formed by the linkage of a very large number of amino acids.

Question 28

Why are proteins important?

Answer 28

They perform many important functions in a cell, serving as nutrients and enzymes; storage molecules for carbon, nitrogen, and energy; and structural components.

Question 29

What four groups are proteins sorted into?

Answer 29

The structure of a protein is a critical determinant of its function and is described by a graduated classification: primary, secondary, tertiary, and quaternary.

Question 30

What are conjugated proteins?

Answer 30

Conjugated proteins have a nonpolypeptide portion that can be a carbohydrate (forming a glycoprotein) or a lipid fraction (forming a lipoprotein). These proteins are important components of membranes.

Question 31

Why is it important to accurately identify bacteria?

Answer 31

Accurate identification of bacteria is essential in a clinical laboratory for diagnostic and management of epidemics, pandemics, and food poisoning caused by bacterial outbreaks.

Question 32

What are some identification techniques?

Answer 32

• Microbes can be identified by determining their lipid compositions, using fatty acid methyl esters (FAME) or phospholipid-derived fatty acids (PLFA) analysis.
• Proteomic analysis, the study of all accumulated proteins of an organism; can also
  be used for bacterial identification.
• Glycoproteins in the plasma membrane or cell wall structures can bind to lectins
  or antibodies and can be used for identification.