Gene Interaction

Question 1

When discrete phenotypic categories are produced that vary from one another in a qualitative way

Answer 1

Discontinuous variation

Question 2

Phenotypic categories vary in a quantitative way

Answer 2

Continuous variation

Question 3

is a form of gene interaction in which one gene masks the phenotypic expression of another gene at a different locus

Answer 3

Epistasis

Question 4

*alleles that are masking the effect

Answer 4

epistatic alleles

Question 5

*alleles whose effect is being masked

Answer 5

hypostatic alleles

Question 6

Fur color in Labrador Retrievers is controlled by two separate genes.
 Fur color is a __________ trait!

Gene 1: Represented by B
: Controls color
Gene 2: Represented by E
: Controls expression of B

Answer 6

polygenic

Question 7

Recessive at one either locus masks the expression of the dominant phenotype at the other locus.

Answer 7

Duplicate Recessive (9:7)

Question 8

Recessive Trait at one locus masks the effect of the second locus.

Answer 8

Single Recessive (9:3:4)

Question 9

• The dominant trait at either locus will expression one phenotype, the other phenotype is homozygous at both loci.

Answer 9

Duplicate Dominant (15:1)

Question 10

Dominant trait at one locus masks the expression of the second locus.

Answer 10

Single Dominant (12:3:1)

Question 11

Duplicate effects from the two loci.
The phenotypes are:
* Two dominant
* One dominant
* None dominant.

Answer 11

Dominant ´ Recessive (9:6:1)

Question 12

Pattern of inheritance:
* Involve genes in the nucleus

Answer 12

Maternal effect and epigenetic inheritance

Question 13

Inheritance pattern:
* Involves genes in organelles other than the nucleus
- Mitochondria
- Chloroplasts

Answer 13

Extranuclear inheritance

Question 14

refers to an inheritance pattern for certain nuclear genes in which the genotype of the mother directly determines the phenotype of her offspring
* Surprisingly, the genotypes of the father and offspring themselves do not affect the phenotype of the offspring

Answer 14

Maternal effect

Question 15

Genetic phenomenon?

Phenotype determined by genes located on the sex chromosome

Answer 15

Sex-linked characteristic

Question 16

Genetic phenomenon?

Phenotype determined by genes on autosomal chromosomes that are more readily expressed in one sex

Answer 16

Sex-influenced characteristic

Question 17

Genetic phenomenon?

Phenotype determined by autosomal genes whose expression is limited to one sex

Answer 17

Sex-limited characteristic

Question 18

Genetic phenomenon?

Phenotype determined by nuclear genotype of the maternal parent

Answer 18

Genetic maternal effect

Question 19

Genetic phenomenon?

Phenotype determined by cytoplasmic genes, which are usually inherited entirely from only one parent

Answer 19

Cytoplasmic inheritance

Question 20

Genetic phenomenon?

Phenotype determined by genes whose expression is affected by the sex of the transmitting parent

Answer 20

Genomic imprinting

Question 21

• percentage of individuals that show at least some degree of expression of a mutant genotype
• Ex. If 15 percent of flies with a given mutant genotype show the wild-type appearance, the mutant gene is said to have a ___________ of 85 percent.

Answer 21

penetrance

Question 22

• reflects the range of expression of the mutant genotype.
• Ex. Flies homozygous for the recessive mutant gene eyeless exhibit phenotypes that range from the presence of normal eyes to a partial reduction in size to the complete absence of one or both eyes

Answer 22

Expressivity

Question 23

Type of penetrance:

identical known genotypes yield <100% of expected phenotype

Answer 23

Incomplete penetrance

Question 24

Type of penetrance:

identical known genotypes yield 100% expected phenotype

Answer 24

Complete penetrance

Question 25

Type of expressivity: Identical known genotypes with an expressivity effect yield a range of phenotypes

Answer 25

Variable expressivity

Question 26

Type of expressivity: Identical known genotypes with no expressivity effect yield 100% expected phenotype

Answer 26

Constant expressivity

Question 27

Identical known genotypes produce a broad range of phenotypes, due to varying degrees of gene activation and expression

Answer 27

Incomplete penetrance with variable expressivity

Question 28

Measure the degree to which an allele is expressed at the phenotypic level

Answer 28

Expressivity

Question 29

* the physical location of a gene in relation to other genetic material may influence its expression * Ex. if a region of a chromosome is relocated or rearranged (called a translocation or inversion event), normal expression of genes in that chromosomal region may be modified

Answer 29

POSITION EFFECT

Question 30

* Provides an organisms with its genetic potential- a possible phenotype.

Answer 30

Genotype

Question 31

* Act on organism as it grows to produce an individual with a unique phenotype.

Answer 31

ENVIRONMENTAL FACTORS

Question 32

ENVIRONMENTAL FACTORS INCLUDE SUCH VARIABLES AS:

Answer 32

WIND EXPOSURE WATER AVAILABILITY ACIDITY TEMPERATURE SOIL TYPE LIGHT PREDATION

Question 33

Sources of genetic variation:

Answer 33

Dominant alleles Recessive alleles Mutations Crossing over Independent assortment Gene interactions

Question 34

Sources of environmentally induced variation

Answer 34

Wind Water availability Acidity Temperature Soil type Light Predation

Question 35

Evening primrose produces red flowers when grown at 23°C and white flowers when grown at 18°C

Answer 35

reason behind* chemical activity depends on the kinetic energy of the reacting substances (depends on the surrounding temperature)

Question 36

Some breeds of cat and rabbit have distinctive darker fur on the extremities (called __________) EXAMPLE: Siamese cats, Himalayan rabbits

Answer 36

pointing

Question 37

The environmental influence of a genotype on the phenotype

Answer 37

phenocopy

Question 38

The sex of some animals is determined by the temperature at which they were incubated during embryonic development EXAMPLE: crocodiles, American alligators, and turtles In some species: * - high incubation temperature produce males * - low incubation temperatures produce females * - in some species the opposite is true

Question 39

Plants of the same species produce a smaller or stunted phenotype with higher altitude. Such patterns are observable in vegetation growing on mountainsides. This may be due to the combined effects of:

Answer 39

* 1. Wind exposure * 2. Cooler temperatures * 3. Water availability * 4. Rarified atmosphere (low oxygen)

Question 40

The presence of other members of the same species may control the determination of sex in other individuals of the group. EXAMPLE: ________________ * 1. These fish live in groups comprising females and juveniles with a single male. * 2. In the presence of the male, all juvenile fish of this species grow into females. * 3. When the male dies, the dominant female will change her sex to become a male for the group.

Answer 40

Sandagers wrasse (parrotfish)

Question 41

In microorganisms, mutations that prevent synthesis of nutrient molecules are quite common, such as when an enzyme essential to a biosynthetic pathway becomes inactive What do you call these organisms?

Answer 41

Auxotroph

Question 42

EXAMPLE: _______________ * If can no longer synthesize the amino acid leucine, proteins cannot be synthesized * If leucine is present in the growth medium, the detrimental effect is overcome.

Answer 42

bread mold Neurospora

Question 43

Cannot metabolize the amino acid phenylalanine

Answer 43

Phenylketonuria

Question 44

Cannot metabolize galactose

Answer 44

Galactosemia

Question 45

Cannot metabolize lactose

Answer 45

Lactose intolerance

Question 46

The color of some flowers is determined by the pH of the soil they grow in. EXAMPLE: Flower color in _______ * Acid soil – _________ * Alkaline soil – ________

Answer 46

hydrangeas pink flowers blue flowers

Question 47

The sedative drug caused improper development of the fetus leading to abnormally stunted limbs

Answer 47

thalidomide

Question 48

What is the gene interaction if the ratio is 9:3:3:1

Answer 48

Additive

Question 49

What is the gene interaction if the ratio is 9:7

Answer 49

Complementary

Question 50

What is the gene interaction if the ratio is 9:3:4

Answer 50

Recessive epistasis

Question 51

What is the gene interaction if the ratio is 12:3:1

Answer 51

Dominant epistasis

Question 52

What is the gene interaction if the ratio is 15:1

Answer 52

Duplicate genes