genetics- breeding

Question 1

define: Genetics

Answer 1

field of biology that studies heredity or the passing of traits from parents to offspring

Question 2

define: trait

Answer 2

an inherited characteristic such as eye colour or hair colour

Question 3

Gregor Mendel

Answer 3

discovered how traits are inherited by experimenting with pea plants

used true breeding pea plants

first offspring is first generation or f1

f1 self fertilize and create f2

Question 4

Chromosomes may carry

Answer 4

different alleles

Question 5

during gamete formation what happens?

Answer 5

pieces of homologous chromosomes separate

Question 6

each gamete receives what?

Answer 6

one chromosome from each pair so it receives one allele of each pair

Question 7

during fertilization, when male and female gametes meet, what happens?

Answer 7

homologous chromosomes and alleles are paired again

each gamete contributed an allele for each trait

Question 8

The Law of Segregation States that:

Answer 8

alleles for a trait separate during meiosis

Question 9

Each gamete carries what?

Answer 9

one allele for each trait

Question 10

Dominant Alleles will:

Answer 10

always be expressed if present

Question 11

Recessive alleles will:

Answer 11

be expressed only if there are two recessive alleles

Question 12

define: Phenotype

Answer 12

the physical description of an organisms trait

Question 13

define: Genotype

Answer 13

the specific combination of alleles an organism has for a trait

Question 14

define: Homozygous

Answer 14

an organism with two of the same alleles for a particular trait

Question 15

define: Heterozygous

Answer 15

an organisms with two different alleles for a particular trait

Question 16

What are the three possible genotypes?

Answer 16

Homozygous dominant, Homozygous recessive and Heterozygous

Question 17

A genetic cross is:

Answer 17

the deliberate mating between a genetic male and a genetic female or parents

Question 18

monohybrid cross

Answer 18

considers one trait

symbol X represents the word cross

Question 19

what is a Hybrid

Answer 19

an offspring that has different traits from its parents

Question 20

a punnet square is used to:

Answer 20

help determine the probability of inheriting traits in a monohybrid cross
shows genotypes of parent and offspring
genotypes of offspring are all possible combinations of alleles that can occur when gametes combine during fertilization

Question 21

Phenotypic ratio shows

Answer 21

the frequency of the phenotypes in the offspring

ex. 2 black: 1 white

Question 22

Genotypic ratio shows

Answer 22

the frequency of the genotypes in the offspring

ex. 1BB:2Bb:1bb

Question 23

define: Codominance

Answer 23

the condition in which both alleles for a trait are equally expresses in a heterozygote hybrid: both alleles are dominant

alleles are represented by a capital letter with a superscript for each allele
*an ex would look like H to the power of R and H to the power of W

Question 24

define: Incomplete dominance

Answer 24

the hybrid has a mixture of the traits displayed by its purebred parents
each trait is partly expressed
results in an intermediate phenotype expression of the trait
represented same as codominance

Question 25

define: Sex linked trait

Answer 25

a trait controlled by genes on sex chromosomes

Question 26

define: X linked trait

Answer 26

a trait controlled by genes on the X chromosomes

Question 27

recessive x linked traits affect:

Answer 27

males more often because they have only one x chromosome

Question 28

a carrier is:

Answer 28

a female that has one recessive allele in one of her x chromosomes