Chapter 14 - Mendelian Genetics

Question 1

Who is Gregor Mendel?

Answer 1

Gregor Mendel discovered heredity in garden peas. He entered into a monastery and started breeding garden peas to study inheritance.

Question 2

What did Gregor Mendel do?

Answer 2

He bred garden peas and found different inherited traits in the offspring of the plants.

Question 3

What is true breeding?

Answer 3

True breeding are generations of plants that are self pollinated and have the same traits (parent plants)

Question 4

What is hybridization?

Answer 4

The crossing of two true-breeding (parent) varieties.

Question 5

What is the P Generation?

Answer 5

Parental generation

Question 6

What is the F1 generation?

Answer 6

1st filial generation (filial comes from the latin word for son)

Question 7

What is the F2 generation?

Answer 7

2nd filial generation (filial comes from the latin word for son)

Question 8

what is a phenotype?

Answer 8

the observable traits, What you can see on the appearance

Question 9

What is a genotype?

Answer 9

the genetic make up

Question 10

What is the 1st part of the Mendel’s Model?

Answer 10

Alternate versions of genes account for variations in inherited characters. These alternate versions are called alleles.

Question 11

What is the 2nd part of Mendel’s Model?

Answer 11

For each character, an organism inherits two copies of a gene, one from each parent

Question 12

What is the 3rd part of Mendel’s Model?

Answer 12

If the two alleles at a locus differ, then one, the dominant allele, will determime the organism’s appearance; the other, the recessive allele, has no noticeable effect on the organism’s appearance.

Question 13

What is the 4th part of Mendel’s Model?

Answer 13

Is The law of segregation which states two alleles for a heritable character segregate during gamete formation and end up in different gametes.

Question 14

What is Mendel’s Model?

Answer 14

It is a model that Mendel developed to explain the 3:1 inheritance pattern that he consistently observed among the F2 offspring in his pea experiments.

Question 15

What is a Homozygous gene?

Answer 15

A pair of identical alleles for a gene (PP, pp, etc.)

Question 16

What is a heterozygous gene?

Answer 16

A pair of two different alleles for a gene (Pp, etc.)

Question 17

What is an allele?

Answer 17

alternative versions of a gene; ex. Pp a Capital P and a lower case p are two different alleles.

Question 18

What does testcross mean?

Answer 18

It is the breeding of an organism of unknown genotype with a recessive homozygote to figure out the unknown genotype.

Question 19

What is a monohybrid?

Answer 19

They are heterozygous for one characteristic being followed through the cross

Question 20

What is a dihybrid?

Answer 20

Heterozygous for two characteristics being followed through the cross.

Question 21

What is the Law of Independent Assortment?

Answer 21

• Each pair of alleles segregate independently of each other pair of alleles during gamete formation.
• The law only applies to genes (allele pairs) located on different chromosomes
• Mendel test using Dihybrid crosses

Question 22

Laws of probability is…?

Answer 22

You have a 50% chance of getting one of the alleles from one of the gametes. Its like flipping a coin.

Question 23

What is the multiplication rule?

Answer 23

Ex. When you try to determine the probability that two or more independent events will occur together in some specific combination, you will multiply the probability of one event happening by the probability of the other event. Then you can find the probability of events happening at the same time.

Question 24

When do you use the addition rule?

Answer 24

If you are looking for the probability of more than one outcome.

Question 25

What is Incomplete dominance?

Answer 25

Neither allele is completely dominant heterozygous offspring will be somewhere in between the parent alleles. (A mixture of colors: Red and white flowers breed and make pink offspring)

Question 26

What is Codominance?

Answer 26

Two alleles each will affect the phenotype in separate, distinguishable ways.. (They both show up)

Question 27

What is Multiple Alleles?

Answer 27

Even though pea plants have two alleles, most genes have more than two alleles. (Ex. Blood types: I^A, I^B, i; A, AB, B or O)

Question 28

What is Pleiotropy?

Answer 28

A gene affects more than one trait.

Question 29

What is Epistasis?

Answer 29

The phenotypic expression of a gene at one locus alters that of a gene at a second locus. (Ex. Labrador retrievers; Black Labs will breed and will create offspring with brown, black and golden fur.)

Question 30

What is Polygenic Inheritance?

Answer 30

Its the additive effect of two or more genes on a single phenotypic character. Like shades of skin color.

Question 31

What is Quantitative Characters?

Answer 31

Characteristics that vary in a population in gradations along a continuum

• Usually due to genetic input from two or more genes
• Examples - skin color, height, eye color

Question 32

Can Nature effect phenotypes?

Answer 32

Hydrangea flowers range in color due to acidity and aluminum content of the soil.

Question 33

What is a Pedigree?

Answer 33

A pedigree analysis can trace where certain traits come from

- diseases can be traced back through a family.