MODIFICATION OF MENDELIAN RATIOS

Question 1

ALLELES ALTER PHENOTYPES IN DIFFERENT WAYS:
most frequently encountered allele in a population, arbitrarily considered as normal.

Answer 1

WILD-TYPE ALLELE

Question 2

ALLELES ALTER PHENOTYPES IN DIFFERENT WAYS:
Modification of genetic sequence

Answer 2

MUTATION

Question 3

ALLELES ALTER PHENOTYPES IN DIFFERENT WAYS:
Mutation that brough about diminished functionality of the gene

Answer 3

LOSS OF FUNCTION MUTATION

Question 4

ALLELES ALTER PHENOTYPES IN DIFFERENT WAYS:
Eventual loss of function of a gene due to mutation

Answer 4

NULL ALLELE

Question 5

ALLELES ALTER PHENOTYPES IN DIFFERENT WAYS:
Increased activity of a gene due to mutation

Answer 5

GAIN OF FUNCTION MUTATION

Question 6

ALLELES ALTER PHENOTYPES IN DIFFERENT WAYS:
Mutation in a gene that does not necessarily altered its activity

Answer 6

NEUTRAL MUTATION

Question 7

GENETICISTS USE A VARIETY OF SYMBOL FOR ALLELES:
Lowercase and italicized (dd)

Answer 7

RECESSIVE ALLELE

Question 8

GENETICISTS USE A VARIETY OF SYMBOL FOR ALLELES:
Uppercase and italicized (DD)

Answer 8

DOMINANT ALLELE

Question 9

In a population of organisms, the presence of three or more alleles of the same gene.

Answer 9

MULTIPLE ALLELES

Question 10

The ABO Blood Group was discovered by

Answer 10

KARL LANDSTEINER

Question 11

The simplest case of multiple alleles is that which three alternative alleles of one gene exist

Answer 11

THE ABO BLOOD GROUP

Question 12

A rare variant of the ABO antigen system in which affected individuals do not have A or B antigens and thus appear to have blood type O, even though their genotype may carry unexpressed alleles for the A and/or B antigens.

Answer 12

THE BOMBAY PHENOTYPE

Question 13

Genetic mutation which might lead to death

Genes function primarily for the expression/production of substances essential to life,

Answer 13

LETHAL ALLELES

Question 14

LETHAL ALLELES:
The lethal mutation is present (mutation that leads to total non-functionality of the gene) but there is another allele that may compensate.

Answer 14

HETEROZYGOUS RECESSIVE LETHAL ALLELE

Question 15

LETHAL ALLELE:
Lethal indeed

Answer 15

HOMOZYGOUS RECESSIVE LETHAL ALLELE

Question 16

LETHAL ALLELE
Inheritance of even just one copy is lethal

Answer 16

DOMINANT LETHAL ALLELE

Question 17

It is defined as the tendency for alleles close together on the same chromosome to be transmitted together as an intact unit through meiosis.

Answer 17

GENETIC LINKAGE

Question 18

PHENOTYPES ARE OFTEN AFFECTED BY MORE THAN ONE GENE:
The non-reciprocal interaction between non-allelic genes such that one gene influences or interferes with the expression of another gene, leading to a specific phenotype.

Answer 18

EPISTASIS

Question 19

PHENOTYPES ARE OFTEN AFFECTED BY MORE THAN ONE GENE:
Other cases of gene interaction yield novel, or new, phenotypes in the F2 generation, in addition to producing modified dihybrid ratios.

Answer 19

NOVEL PHENOTYPES