Mendelian Genetics

Question 1

Analysis of the inheritance of physical characteristics from parent to offspring

Answer 1

Mendelian Genetics

Question 2

Monohybrid crosses yield a ___ phenotypic ration and a ___ genotypic ratio

Answer 2

3:1 and 1:2:1

Question 3

___ prove the Law of Dominance and Law of Segregation

Answer 3

Monohybrid Crosses

Question 4

___ yield a 9:3:3:1 phenotypic ration and a 1:2:1:2:4:2:1:2:1 genotypic ratio

Answer 4

Dihybrid Crosses

Question 5

Dihybrid Crosses prove the ____

Answer 5

Law of Independent Assortment

Question 6

Mating experiment in which the inheritance pattern of a single trait is followed

Answer 6

Monohybrid Cross

Question 7

Mating experiment in which the inheritance of two traits is followed simultaneously

Answer 7

Dihybrid Cross

Question 8

A genetic cross in which two parental organisms are genetically identical

Answer 8

Self-Cross

Question 9

The pair of genetic factors an organism possesses for a certain trait

Answer 9

Genotype

Question 10

The observable physical manifestation of a certain trait

Answer 10

Phenotype

Question 11

One of the possible variations of a trait’s expression

Answer 11

Allele

Question 12

The allele of a gene that is observed in hybrid organisms

Answer 12

Dominant

Question 13

The allele of a gene that is not observed in hybrid organisms

Answer 13

Recessive

Question 14

Describes a genotype in which the two alleles are identical

Answer 14

Homozygous

Question 15

Describes a genotype in which the two alleles are different

Answer 15

Heterozygous

Question 16

A genetic cross in which an organism of unknown genotype is crossed with an organism known to be homozygous recessive

Answer 16

Test-Cross

Question 17

A chart that depicts the results of a genetic cross

Answer 17

Punnett Square

Question 18

Neither allele is truly dominant. Heterozygous organisms exhibit an intermediate phenotype

Answer 18

Incomplete Dominance

Question 19

Both alleles exhibit dominance, neither is masked. Heterozygous organisms exhibit both alleles simultaneously

Answer 19

Codominance

Question 20

More than two potential variants/alleles exist in the population. There are more possible genotypes for these traits

Answer 20

Multiple Alleles

Question 21

Many characteristics are controlled by the combined influence of several genes. The result is a very broad range of phenotypes for the characteristic. E.g. Pigmentation

Answer 21

Polygenic Inheritance

Question 22

One gene/locus may affect several phenotypes

Answer 22

Pleiotropy

Question 23

Less than 100% of the individuals who are genetically expected to exhibit a certain phenotype actually exhibit that phenotype

Answer 23

Incomplete Penetrance

Question 24

The degree to which a trait is expressed varies greatly among individuals bearing the associated genotype

Answer 24

Variable Expressivity

Question 25

Sex can prevent the expression of some autosomal genes (Ovarian development)

Answer 25

Sex Limited

Question 26

Sex (Male v Female) can modify the expression of some autosomal genes (Pattern Baldness)

Answer 26

Sex Influenced

Question 27

Two non-allelic genes interact. One genotype masks (prevents) the expression of a phenotype for the other gene

Answer 27

Epistasis

Question 28

There may be multiple genetic sources of the same mutant phenotype

Answer 28

Complementation

Question 29

In some genes, the mother’s phenotype influences how the offspring’s genotype is expressed as a phenotype

Answer 29

Maternal Effect

Question 30

Way of “marking” a gene for cellular recognition.

Answer 30

Imprinting

Question 31

Adding ___ to the cytosine nucleotides is one way to mark/imprint a gene

Answer 31

Methyl groups

Question 32

During gamete formation or early embryonic development, a gene can be inactivated

Answer 32

Epigenectics

Question 33

The Slipper limpet (a sea mollusk) embryo develops a certain gender in response to the surface upon which the embryo lands. If it lands on sand or on a male, develops as a female. If it lands on a female, it develops as a male

Answer 33

Environmental Determination

Question 34

Refers to a pair of chromosomes that have different composition

Answer 34

Heteromorphic

Question 35

Refers to homologous chromosome pairs, not direct determinants of sex

Answer 35

Autosomes

Question 36

The sex/gender possessing a homologous pair of sex determination chromosomes

Answer 36

Homogametic

Question 37

The sex/gender possessing a mismatched (hetermorphic) pair of sex determination chromosomes

Answer 37

Heterogametic

Question 38

In ___ the ratio of X chromosomes to autosomes is the basic determining factor

Answer 38

Drosophila

Question 39

XX Numerator homodimers are a transcription activator for a gene on the X chromosome called __

Answer 39

Sxl

Question 40

The ___ is made early in female development. It stimulates the activity of a second gene, called tra

Answer 40

SXL peptide

Question 41

Expression of __ directs the editing/splicing of a third gene, dsx

Answer 41

Tra

Question 42

When tra is active, __ is spliced in a different way, ultimately leading to the molecules needed for male structures

Answer 42

Dsx

Question 43

___ plays a significant role in the development of sex phenotypes in Drosophila

Answer 43

Epistasis

Question 44

All early embryos have a ___ that includes a medulla and a cortex

Answer 44

Pre-gonad

Question 45

Can be induced to develop testes

Answer 45

Medulla

Question 46

Can be induced to develop into ovaries

Answer 46

Cortex

Question 47

If ___ gene is present, it codes for the ___

Answer 47

SRY, Testis Determination Factor (TDF)

Question 48

___ boosts androgen gene expression

Answer 48

TDF

Question 49

TDF also serves boosts the expression of an autosomal gene called ___

Answer 49

MIS

Question 50

___ destroys ovarian tissue that was beginning to form in the

Answer 50

MIS

Question 51

___ also suppresses the expression of the Ovarian development genes

Answer 51

MIS

Question 52

X chromosomes contain a gene called Xic, it codes for an RNA called ___

Answer 52

Xist= X inactivation specific transcript

Question 53

Methylation is an ___ on the X chromosome

Answer 53

Imprint

Question 54

Permanently condensed X chromosomes

Answer 54

Barr Bodies