Chapter 16

Question 1

Blending hypothesis

Answer 1

The idea that genetic material from the two parents blend together (blue and yellow paint becoming green)

Question 2

Particulate hypothesis

Answer 2

the idea that parents pass on discrete heritable units (genes)

Question 3

Character

Answer 3

A heritable feature that varies among individuals (flower color)

Question 4

Trait

Answer 4

Each variant of character, such as purple or white color for flowers

Question 5

True-breeding

Answer 5

organism that produce offspring of the same variety when they self-pollinate

Question 6

hybridization

Answer 6

the mating of two contrasting, true-breeding varieties

Question 7

P generation

Answer 7

the true-breeding parents

Question 8

F₁ generation

Answer 8

The hybrid offspring of the P generation

Question 9

F₂ generation

Answer 9

The offspring produced when F₁ individuals self-pollinate or cross pollinate with other F₁ hybrids

Question 10

alleles

Answer 10

the alternative versions of a gene

Question 11

Mendel’s model first concept

Answer 11

Alternative versions of genes account for variations in inherited characters

Question 12

Mendel’s model second concept

Answer 12

For each character, an organism inherits two alleles, one from each parent

Question 13

Mendel’s model third concept

Answer 13

If the two alleles at a locus differ, then one (the dominant allele) determines the organism’s phenotype, and the other (the recessive allele) has no noticeable effect on the phenotype

Question 14

Mendel’s model fourth concept

Answer 14

The law of segregation; the two alleles for a heritable character separate during gamete formation and end up in different gametes

Question 15

Homozygote

Answer 15

An organism with two identical alleles for a character

Question 16

Heterozygote

Answer 16

An organism with two different alleles for a gene

Question 17

Phenotype

Answer 17

physical appearance

Question 18

Genotype

Answer 18

genetic makeup

Question 19

testcross

Answer 19

breeding the mystery individual with a homozygous recessive individual

Question 20

law of independent assortment

Answer 20

Each pair of alleles segregates independently of any other pair of alleles during gamete formation

Question 21

multiplication rule

Answer 21

the probability that two or more independent events will occur together is the product of their individual probabilities

Question 22

addition rule

Answer 22

the probability that any one or two or more mutually exclusive events will occur is calculated by adding together their individual probabilities

Question 23

Watson and Crick

Answer 23

Introduced the double-helical model for DNA

Question 24

T. H. Morgan

Answer 24

Showed that genes were located on chromosomes; this spurred on the search for the true genetic material: DNA or proteins

Question 25

bacteriophages

Answer 25

Or phages, viruses widely used in molecular genetic research

Question 26

Virus

Answer 26

A DNA (sometimes RNA) enclosed by a protective coat, often simply protein

Question 27

Hershey and Chase

Answer 27

Discovered that DNA is the genetic material using phages and radioactivity

Question 28

antiparallel

Answer 28

DNA's subunits run in opposite directions

Question 29

Watson and Crick believed that based pairs paired with _________ pairs (A with __)

Answer 29

like; A

Question 30

A purine (A or G) pairs with a _______

Answer 30

pyrimidine (C or T)

Question 31

DNA replication is ________

Answer 31

Semi-conservative

Question 32

Semiconservative model

Answer 32

When DNA replicates, each daughter molecule will have one old strand and one newly made strand

Question 33

Meselson and Stahl

Answer 33

Proved the semi-conservative model of DNA replication by culturing bacteria with a heavy isotope, letting it replicate, and then culturing it in a lighter isotope. When centrifuged, two bands of DNA occurred

Question 34

Origins of replication

Answer 34

The particular site where replications begins, where the two NA strands are separated, opening up a replication bubble

Question 35

DNA is made in the _______ direction

Answer 35

5'-to-3'

Question 36

Primer

Answer 36

the initial nucleotide strand (RNA) that is 5-10 nucleotides long

Question 37

primase

Answer 37

an enzyme that synthesizes primers

Question 38

DNA polymerase

Answer 38

enzymes that catalyze the synthesis of new DNA at a replication fork

Question 39

Each nucleotide that is added to a growing DNA strand is a ____________

Answer 39

nucleoside triphosphate

Question 40

______ supplies adenine to DNA

Answer 40

dATP

Question 41

Leading strand

Answer 41

moves toward the replication fork

Question 42

lagging strand

Answer 42

works in the direction away from the replication fork

Question 43

Okazaki fragments

Answer 43

The name for the fragments which make up the lagging strand

Question 44

DNA ligase

Answer 44

Join together the Okazaki fragments