Chapter 10.3

Question 1

MONOHYBRID CROSS

Answer 1

a mating between individuals that are both heterozygous for the same gene

Question 2

PUNNETTE square

Answer 2

uses the allele combination ( genotype ) of the parents to reveal which allele combinations the offspring may inherit

Question 3

Homozygous recessive

Answer 3

are the only way to describe a receive gene that is expressed in a phenotype

Question 4

what are the 2 possibilities of a dominant allele

Answer 4

Yy or YY ( homozygous dominant or heterozygous dominant)

Question 5

TEST CROSS

Answer 5

is an experiment to help determine which dominant genotype a (YY or Yy) a offspring has
It is a mating between the two possibilities of unknown genotype (YY or Yy) with a homozygous recessive individual (yy)
to determine the unknown genotype.

( to determine the unknown genotype ( whether YY or Yy) of a plant it is crossed with a homologous recessive individual)

If the offspring are all the same their is 100% chance that the parent was a homologus dominant

If the offerings were divided (50%) in half there parent would heterozygous dominant Yy)

Question 6

ALTERNATIVE VERSIONS

Answer 6

Medndel term for alleles

Question 7

LAW OF SEGREGATION

Answer 7

although each parent gets a version of a gene , an allele, that may be different or the same, the homologs they reside on are separated in anaphase of meiosis I and pulled to opposite ends of the cell. So the homologous alleles of a gene are separated and are finally placed in different gametes

. Two alleles of each gene are packaged into separate gametes

.During meiosis , homologous pairs of chromosomes ( and the gene they carry) segregate from one another and a packaged into separate gametes.
At fertilization, gametes combine at random to form the next generation

Question 8

following mendels law of segregation a plant genotype of Yy would produce gametes carrying

Answer 8

50 % Y( goes into one gamete) and 50 % y ( goes into the other)

Question 9

following mendels law of segregation a plant genotype of YY would produce gametes carrying

Answer 9

Y in one gamete Y in the other

Question 10

1. What is a monohybrid cross, and what are the genotypic and phenotypic ratios expected in the offspring of the cross?

Answer 10

A monohybrid cross is a mating between two individuals that are both heterozygous for one gene. The genotypic ratio expected in a monohybrid cross is 1:2:1; the phenotypic ratio is 3:1.

Question 11

How are Punnett squares helpful in following inheritance of single genes?

Answer 11

Punnett squares show the genotypes of each parent as well as the genotypes of potential offspring. Phenotypic and genotypic ratios of offspring can be predicted from the data in Punnett squares.

Question 12

What is a test cross, and why is it useful?

Answer 12

A test cross is a mating between a homozygous recessive individual and an individual of unknown genotype. The genotype of the unknown parent can be deduced from the ratio of phenotypes in the F1 generation.

Question 13

How does the law of segregation reflect the events of meiosis?

Answer 13

The law of segregation reflects the movement of homologous chromosomes into separate cells during meiosis I.

Question 14

When heterozygous plants self fertilize, phenotype occurs in a distinct ratio

Answer 14

9:3:3:1

Question 15

DIHYBRID CROSS

Answer 15

is a mating between individuals that are heterozygous for two genes

Question 16

An individual with the genotype RrYy would produce approx equal numbers of of four types of gametes ( 4 phenotypes)

Answer 16

RY,ry,Ry and rY

Question 17

dihybrd would have how many possibilities of offspring

Answer 17

16 with a phenotypic ratio of 9:3:3:1

Question 18

THE LAW OF INDEPENDENT ASSORTMENT

Answer 18

based on dihybrid cross
. inference to metaphase in I in meiosis
. It states that during gamete formation, the segregation of alleles for one gene does not influence the alleles for another gene( provided that the genes are on sperate chromosomes
. alleles for two different gens are a re randomly packaged into gametes.

Question 19

THE PRODUCT RULE

Answer 19

States that the chance that two independent events will occur = the product of the individual chances that each event will occur

. to calculate the offspring possibility for each gene from heterozygous parents e.g.. ( RrYy) set up Psquares for each (Rr xRr)
then Yy x Yy. calculate the ratio for whatever specific gamete you re looking for for each then multiply the answers of each gene together.

Or just find out for one offspring and raise it to number of offsprings

Question 20

When does the law of independent assortment of snot apply

Answer 20

genes that close together on the same chromosome

Question 21

What is a dihybrid cross, and what is the phenotypic ratio expected in the offspring of the cross?

Answer 21

In a dihybrid cross, two individuals that are heterozygous for two genes are mated. The phenotypic ratio that is expected is 9:3:3:1.

Question 22

. How does the law of independent assortment reflect the events of meiosis?

Answer 22

The law of independent assortment reflects that each homologous pair of chromosomes aligns independently of other chromosome pairs during metaphase I of meiosi

Question 23

How can the product rule be used to predict the results of crosses in which multiple genes are studied simultaneously?

Answer 23

The product rule allows you to estimate the odds that an offspring will have a certain combination of alleles for multiple genes by multiplying the probability that each separate event will occur.