Ch 15 Non Medelian Genetics

Question 1

chromosome theory of inheritance

Answer 1

Mendelian genes have specific loci (sites) along chromosomes, and it is the chromosomes that undergo segregation and independent assortment.

Question 2

wild type

Answer 2

the phenotype for a character most commonly observed in natural populations

Question 3

sex linked gene

Answer 3

genes on either sex chromosome, many unrelated to sex
X - 1,100
Y - 78

Question 4

Hemophilia

Answer 4

X linked recessive disorder

Question 5

Barr Body

Answer 5

Condensed inactive X in each cell of a female

Question 6

linked genes

Answer 6

genes located near each other on the same chromosome; tend to be inherited together in genetic crosses

Question 7

genetic recombination

Answer 7

the production of offspring with combinations of traits that differ from those found in either P generation parent

Question 8

parental types

Answer 8

when phenotypes of offspring match the P generation

Question 9

recombinant types/recombinants

Answer 9

phenotypes are new combinations

Question 10

crossing over

Answer 10

the recombination of linked genes

Question 11

genetic map

Answer 11

an ordered list of the genetic loci along a particular chromosome

Question 12

linkage map

Answer 12

a genetic map based on recombination frequency

Question 13

map unit

Answer 13

one map unit is 1% recombination frequency

Question 14

nondisjunction

Answer 14

one gamete receives two of the same type of chromosome

Question 15

aneuploidy

Answer 15

either of the aberant (abnormal) gametes unites with a normal one at fertilization, the zygote will also have an abnormal number of a particular chromosome

monosomic - the cell has 2n-1 chromosomes
trisomic - has 2n+1 chromosomes

Question 16

deletion

Answer 16

error in meiosis where a chromosomal fragment is lost

Question 17

duplication

Answer 17

error in meiosis where a broken fragment becomes reattached as an extra segment

Question 18

inversion

Answer 18

error in meiosis where a chromosomal fragment reattaches to the original chromosome

Question 19

translocation

Answer 19

error in meiosis where a fragment joines a nonhomologous chromosome

Question 20

genomic imprinting

Answer 20

expresson of an allele in offspring depends on whether the allele is inherited from the male or female parent