MENDELIAN GENETICS

Question 1

• Gregor Johann Mendel
• 1866
• major postulates of transmission genetics
• garden pea (Pisum sativum)
• discrete units of inheritance exist and predicted their behavior during the formation of gametes (elementen)
• Mendel’s postulates were accepted as the basis for the study of what is known as transmission genetics.

Answer 1

MENDELIAN GENETICS

Question 2

• easy to grow and hybridize
  artificially
• self-fertilizing in nature
• seven visible features (unit characters), each represented by two contrasting forms, or traits
• Character: stem height: traits: tall and dwarf
• He selected six other visibly contrasting pairs of traits involving seed shape and color, pod shape and color, and pod and flower arrangement.

Answer 2

GARDEN PEA

Question 3

Mendel’s simplest crosses involved only one pair of contrasting traits from two parent strains, each exhibiting one of the two contrasting forms of the character under study

Answer 3

MONOHYBRID CROSS

Question 4

Offspring of self-fertilizing individuals

Answer 4

SELFING

Question 5

MENDELIANS’ FIRST THREE POSTULATES:
Genetic characters are controlled by unit factors that exist in pairs in individual organisms.

Answer 5

UNIT FACTORS IN PAIRS

Question 6

MENDELIANS’ FIRST THREE POSTULATES:
When two unlike unit factors responsible for a single character are present in a single individual, one unit factor is dominant to the other, which is said to be recessive.

Answer 6

DOMINANCE/RECESSIVENESS

Question 7

MENDELIANS’ FIRST THREE POSTULATES:
During the formation of gametes, the paired unit factors separate or segregate randomly so that each gamete receives one or the other with equal likelihood.

Answer 7

SEGREGATION

Question 8

MODERN GENETIC TERMINOLOGY:
The physical appearance of a trait is the ____ of the individual.

Answer 8

PHENOTYPE

Question 9

MODERN GENETIC TERMINOLOGY:
Mendel’s unit factors represent units of inheritance called ___ by modern geneticists.

Answer 9

GENES

Question 10

MODERN GENETIC TERMINOLOGY:
The phenotype is determined by alternative forms of a single gene called

Answer 10

ALLELES

Question 11

MODERN GENETIC TERMINOLOGY:
When alleles are written in pairs to represent the two unit factors (DD, Dd, or dd), these symbols are called the ____.

Answer 11

GENOTYPE

Question 12

MODERN GENETIC TERMINOLOGY:
When both alleles are the same (DD or dd), the individual is _____ or a ______.

Answer 12

HOMOZYGOUS OR A HOMOZYGOTE

Question 13

MODERN GENETIC TERMINOLOGY:
When the alleles are different (Dd), we use the term ____ or a ____.

Answer 13

HETEROZYGOUS OR A HETEROZYGOTE

Question 14

TERMINOLOGIES:
The genetic constitution of a individual (PP, Pp, pp)

Answer 14

GENOTYPE

Question 15

TERMINOLOGIES:
The outward appearance of an individual (purple, white)

Answer 15

PHENOTYPE

Question 16

TERMINOLOGIES:
The phenotype seen when two alternative alleles are present together (Pp: purple)

Answer 16

DOMINANT PHENOTYPE

Question 17

TERMINOLOGIES:
The form of the gene that is expressed when two alternative alleles are present together (P>p)

Answer 17

DOMINANT ALLELE

Question 18

TERMINOLOGIES:
The form of the gene that is not expressed when two alternative alleles are present together.

Answer 18

RECESSIVE ALLELE

Question 19

TERMINOLOGIES:
The phenotype that is only seen when two identical alleles are found together (pp: white)

Answer 19

RECESSIVE PHENOTYPE

Question 20

TERMINOLOGIES:
having two identical alleles (PP or pp)

Answer 20

HOMOZYGOUS

Question 21

TERMINOLOGIES:
having two different alleles (Pp)

Answer 21

HETEROZYGOUS

Question 22

Punnett square was named after

Answer 22

Reginald C. Punnett

Question 23

PUNNETT SQUARES:
The vertical column represents those of the ___ parent

Answer 23

FEMALE

Question 24

PUNNETT SQUARES:
The horizontal row represents those of the ___ parent.

Answer 24

MALE

Question 25

PUNNETT SQUARES: The process thus lists all possible

Answer 25

RANDOM FERTILIZATION EVENTS

Question 26

PUNNETT SQUARES: The genotypes and phenotypes of all potential offspring are

Answer 26

ASCERTAINED

Question 27

THE TESTCROSS: ONE CHARACTER A test cross resulting in all dominant offspring indicates that the parent is ____

Answer 27

HOMOZYGOUS DOMINANT

Question 28

THE TESTCROSS: ONE CHARACTER: A test cross resulting in a 1:1 ratio of yellow to green offspring indicates that the parent is _____

Answer 28

HETEROZYGOUS

Question 29

To distinguish the genotype, Mendel devised the _____. The organism expressing the dominant phenotype, but of unknown genotype, is crossed to a known homozygous recessive individual.

Answer 29

TESTCROSS METHOD

Question 30

Such a cross, involving two pairs of contrasting traits, is a

Answer 30

DIHYBRID CROSS OR TWO-FACTOR CROSS

Question 31

On the basis of similar results in numerous dihybrid crosses, Mendel proposed a fourth postulate called This postulate stipulates that segregation of any pair of unit factors occurs independently of all others. As a result of random segregation, each gamete receives one member of every pair of unit factors. All possible combinations of gametes are formed in equal frequency

Answer 31

INDEPENDENT ASSORTMENT

Question 32

Three pairs of contrasting traits, in what is called a When F1 individuals serve as parents, each produces eight different gametes in equal frequencies At this point, we could construct a Punnett square with 64 separate boxes and read out the phenotypes

Answer 32

TRIHYBRID CROSS OR THREE-FACTOR CROSS

Question 33

Such a family tree is called a Forked-Line Method or Branch Diagram

Answer 33

PEDIGREE

Question 34

Fraternal twins or also known as

Answer 34

DIZYGOTIC TWINS (sex may be the same or different)

Question 35

Identical twins or also known as

Answer 35

MONOZYGOTIC TWINS (sex may be the same)