Test one

Question 1

what is genetics

Answer 1

the study of heredity or the study of biological information

Question 2

what do we use as our experimental model organism

Answer 2

Drosophila melanogaster

Question 3

what is the life cycle of a drosophila

Answer 3

embryo
first instar larva
second instar larva
third instar larva
pupa
adult

Question 4

what on a virgin will you find on their abdomen

Answer 4

meconium

Question 5

what principles of genetic did Mendel discover

Answer 5

law of segregation

law of independent assortment

Question 6

what was the first scientist to combine data collection, analysis, and theory to discover the basic principles of genetics

Answer 6

gregor mendel

Question 7

why did mendel use peas in his experiment

Answer 7

breeding could be done by cross fertilization or selfing
large # of progeny in short period of time
traits remained constant in crosses within a line

Question 8

what determines traits

Answer 8

genes
one from mother
one from father

Question 9

each gene comes in alternative forms which are called

Answer 9

alleles

Question 10

what is a phenotype

Answer 10

an observable characteristic

Question 11

what is a genotype

Answer 11

a pair of alleles in an individual

Question 12

what is an homozygote

Answer 12

two identical alleles

Question 13

what is a heterozygote

Answer 13

two different alleles

Question 14

what are the parent phenotypes of a hybrid cross

Answer 14

one is homo dom and homo recess

Question 15

what is the F1 phenotype of a hybrid cross

Answer 15

all one phenotype

hetero dom

Question 16

what is a simple way to visualize the segregation and random union of alleles

Answer 16

punnett square

Question 17

what can reveal an unknown genotype

Answer 17

a testcross

Question 18

in a monohybrid what is the ratio of phenotypes for the F1 progeny

Answer 18

3:1

Question 19

when a true breeding dihybrid crosses, what is the F1 of this cross

Answer 19

heterozygote

RrYy

Question 20

what is the phenotypic ratio of the F2 generation in a dihybrid

Answer 20

9:3:3:1

Question 21

in the F1 dihybrid produces four possible gametes in what kind of ratio

Answer 21

1:1:1:1
YR
Yr
yR
yr

Question 22

what is the product rule

Answer 22

probability of two independent events occurring together is the product of their individual probabilities

Question 23

if both parents are true bred in dihybrid testcross what is the possible F1

Answer 23

one possible outcome

heterozygote dom

Question 24

if one parent is true bred and one parent is heterozygous for one trait, what does the F1 generation look like

Answer 24

two types of F1 phenotypes

Question 25

if one parent is true bred and one parent is heterozygous for both traits what does the F1 looks like

Answer 25

4 products of F1 generation | shows all four phenotypes

Question 26

what does a chi square test measure

Answer 26

how well the observed results conform the expected results

Question 27

what is a null hypothesis

Answer 27

observed values are no different from expected values

Question 28

what is needed to do a chi square

Answer 28

total number of progeny how many classes of progeny number of offspring observed in each class

Question 29

how to find degrees of freedom

Answer 29

``` df= n- 1 n= number of classes ```

Question 30

where is DNA packed

Answer 30

into highly condensed chromosomes

Question 31

how many chromosomes are present in a drosophila

Answer 31

4

Question 32

what are the steps in mapping a mutant allele

Answer 32

determine chromosome determine the region on the chromosome determine the actual gene locus

Question 33

how can you tell if mutant allele is on x chromosome

Answer 33

all males show the mutant phenotype | males inherit mutant fro mom

Question 34

when are two genes linked

Answer 34

when the parental type is greater than the recombinant type

Question 35

when are two genes not linked

Answer 35

ratio is 1:1:1:1 | parental type is equal in number to recombinant type

Question 36

when does unlinked genes occur

Answer 36

either when two genes are on different chromosomes or when they are sufficiently far apart on the same chromosome that at least one crossover occurs between them in every meiosis

Question 37

what is recombination frequency

Answer 37

percentage of total recombinant progeny

Question 38

where does crossover occurs

Answer 38

chiasmata

Question 39

what else can recombination frequencies be used for

Answer 39

a measure of physical distance between two linked genes

Question 40

in a three point cross, what does the most frequent class represent

Answer 40

parental configuration of alleles

Question 41

in a three point cross, what does the least frequent class represent

Answer 41

double cross overs

Question 42

what is the first step in mapping the genes in relation to each other in a three point cross

Answer 42

identify the middle gene | double cross over

Question 43

deviation from the 1:1:1:1 ratio always mean

Answer 43

linkage

Question 44

what is special about drosophila salivary glands

Answer 44

contain giant chromosomes

Question 45

what are giant chromosomes called

Answer 45

polytene