Chapter 3- The Molecules Of Cells

Question 1

Amino acid

Answer 1

An organic molecule containing a carbonyl group and an amino group; serves as the monomer of proteins.

Question 2

Amino group

Answer 2

A chemical group consisting of a nitrogen atom bonded to two hydrogen atoms.

Question 3

Anabolic steroid

Answer 3

A synthetic variant of the male hormone testosterone that mimics some of its effects

Question 4

Carbohydrate

Answer 4

Member of the class of biological molecules consisting of single-monomer sugars (monosaccharides) two-monomer sugars (disaccharides), and polymers (polysaccharides).

Question 5

Carbonyl group

Answer 5

A chemical group consisting of a carbon atom linked by a double bond to an oxygen atom.

Question 6

Carboxyl group

Answer 6

A chemical group consisting of a carbon atom double-bonded to an oxygen atom and also bonded to a hydroxyl group.

Question 7

Cellulose

Answer 7

A structural polysaccharide of plant cell walls composed of glucose monomers. Cellulose molecules are linked by hydrogen bonds into cable-like fibrils.

Question 8

Disaccharide

Answer 8

A sugar molecule consisting of two monosaccharides linked by a dehydration reaction

Question 9

Double helix

Answer 9

The form of native dna, referring to its two adjacent polynucleotide strands interwound into a spiral shape.

Question 10

Enzyme

Answer 10

A macromolecule, usually a protein, that serves as a biological catalyst, changing the rate of a chemical reaction without being consumed by the reaction.

Question 11

Fat

Answer 11

A lipid composed of three fatty acids linked to one glycerol molecule; a triglyceride. Most fats function as energy-storage molecules.

Question 12

Functional group

Answer 12

A specific configuration of atoms commonly attached to the carbon skeletons of organic molecules and involved in chemical reactions

Question 13

Gene

Answer 13

A discrete unit of hereditary information consisting of a specific nucleotide sequence in DNA (or RNA, in some viruses). Most of the genes of a eukaryote are located in its chromosomal DNA; a few are carried by the DNA of mitochondria and chloroplasts.

Question 14

Gene expression

Answer 14

The process whereby genetic information flows from genes to proteins; the flow of genetic information from the genotype to the phenotype.

Question 15

Glucose

Answer 15

A six-carbon monosaccharide that serves as a building block for many polysaccharides and whose oxidation in cellular respiration is a major source of ATP for cell.

Question 16

Glycogen

Answer 16

An extensively branched glucose storage poly-saccharide found in liver and muscle cells; the animal equivalent of starch.

Question 17

Hydrocarbon

Answer 17

An organic compound composed only of the elements carbon and hydrogen.

Question 18

Hydrolysis

Answer 18

A chemical reaction that breaks bonds between two molecules by the addition of water; process by which polymers are broken down in an essential process of digestion.

Question 19

Hydrophilic

Answer 19

“Water-loving”; pertaining to polar or charged molecules (or parts of molecules) that are soluble in water.

Question 20

Hydrophobic

Answer 20

“Water-fearing”; pertaining to nonpolar molecules (or parts of molecules) that do not dissolve in water.

Question 21

Hydroxyl group

Answer 21

A chemical group consisting of an oxygen atom bonded to a hydrogen atom.

Question 22

ISOmers

Answer 22

Organic compounds with the same molecular formula but different structures and, therefore, different properties.

Question 23

Lipid

Answer 23

An organic compound consisting mainly of carbon and hydrogen linked by nonpolar covalent bonds, making the compound mostly hydrophobic. Lipids include fats, phospholipid, and steroids and are insoluble in water.

Question 24

Macromolecule

Answer 24

A giant molecule (a polysaccharide, protein, or nuclei acid) formed by the joining of smaller molecules, usually by a dehydration reaction.

Question 25

Methyl group

Answer 25

A chemical group consisting of a carbon atom bonded to three hydrogen atoms.

Question 26

Monomer

Answer 26

The subunit that serves as a building block of a polymer.

Question 27

Monosaccharide

Answer 27

The simplest carbohydrate; a simple sugar with a molecular formula that is generally some multiple of CH2O. Monosaccharides are the monomers of disaccharides and polysaccharides.

Question 28

Nuclei canid

Answer 28

A polymer consisting of many nucleotide monomers; serves as a blueprint for proteins and, through the actions of proteins, for all cellular structures and activities. The two types of nuclei acids are DNA and RNA

Question 29

Nucleotide

Answer 29

A building block of nucleic acids, consisting of a five-carbon sugar covalently bonded to a nitrogenous and or or more phosphate groups.

Question 30

Organic compounds

Answer 30

A chemical compound containing the element carbon and usually the element hydrogen.

Question 31

Peptide bond

Answer 31

The covalent bond between two amino acid units in a polypeptide, formed by a dehydration reaction.

Question 32

Phosphate group

Answer 32

A chemical group consisting of a phosphorus atom bonded to four oxygen atoms.

Question 33

Phospholipid

Answer 33

A lipid made up of glycerol joined to two fatty acids and a phosphate group, giving the molecule two non polar hydrophobic tails and a polar hydrophilic head. Phospholipids form bilayers that function as biological membranes.

Question 34

Polymer

Answer 34

A large molecule consisting of many identical or similar monomers linked together by covalent bonds.

Question 35

Polypeptide

Answer 35

A polymer (chain) of amino acids linked by peptide bonds.

Question 36

Polysaccharide

Answer 36

A carbohydrate polymer of many monosaccharides linked by dehydration reactions

Question 37

Primary structures

Answer 37

The first level of protein structures; the specific sequence of amino acids making up a polypeptide chain.

Question 38

Protein

Answer 38

A functional biological molecule consisting of one or more polypeptides folded into a specific three-dimensional structure.

Question 39

Quaternary structure

Answer 39

The fourth level of protein structure; the shape resulting from the association of two or more polypeptide subunits

Question 40

Ribonucleic acid

Answer 40

A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous gases adenine, cytosine, guanine, and uracil; usually single-stranded; functions in protein synthesis, gene regulation, and as the genome of some viruses.

Question 41

Saturated fatty acid

Answer 41

A fatty acid in which all carbons in hydrocarbon tail are connected by single bonds and the maximum number of hydrogen atoms are attached to the carbon skeleton. Saturated fats and fatty acids solidify at room temperature.

Question 42

Secondary structure

Answer 42

The second level of protein structure; the regular local patterns of coils or folds in a polypeptide chain.

Question 43

Starch

Answer 43

A storage polysaccharide in plants; a polymer of glucose.

Question 44

Steroid

Answer 44

A type of of lipid whose carbon skeleton is in the form of four fused rings with various chemical groups attached. Examples are cholesterol, testosterone, and estrogen.

Question 45

Tertiary structure

Answer 45

The third level of protein structure; the overall three-dimensional shape of a polypeptide due to interactions of the r groups of the amino acids making up the chain.

Question 46

Trans fat

Answer 46

An unsaturated fat linked to health risks that is formed artificially during hydrogenation of vegetable oils.

Question 47

Unsaturated fatty acid

Answer 47

A fatty acid that has one or more double bonds between carbons in the hydrocarbon tail and thus lack the maximum number of hydrogen atoms. Unsaturated fats and fatty acids do not solidify st room temperature.