Chapter 11, 12.1-12.2

Question 1

What is a character?

Answer 1

A heritable feature that varies among individuals

Question 2

What is a trait?

Answer 2

Each variant for a character

Question 3

What does it mean to be true breeding?

Answer 3

Organisms that, over many generations, have produced the same genetic variety over and over

Question 4

What is hybridization?

Answer 4

The crossing of 2 true-breeding varieties

Question 5

What is a P generation? the F1 generation?

Answer 5

The generation true breeding parents, their offspring are the F1 generation

Question 6

What are alleles and what are they responsible for?

Answer 6

Alleles are alternative versions of the same gene. The are responsible for variations in inherited characters

Question 7

What is a gene?

Answer 7

A sequence of nucleotides at a specific location along a particular chromosome

Question 8

What is the law of segregation?

Answer 8

A law that states that two alleles for a heritable character segregate during gamete formation and end up in different gametes

Question 9

What is the difference between phenotype and genotype?

Answer 9

Phenotype: physical or physiological makeup

Genotype: Genetic makeup

Question 10

What is a testcross?

Answer 10

A test devised by mendel where you cross either a homozygous dominant or hererozygous genotype(you’re trying to determine which one) with a homozygous recessive and the outcome will give you the genotype of first plant

Question 11

What are monohybrids and what is a monohybrid cross?

Answer 11

A monohybrid is something that is heterozygous for one particular trait and a monohybrid cross is a cross between such heterozygotes

Question 12

What is a dihybrid and a dihybrid cross?

Answer 12

Individuals that are heterozygous for 2 characteristics, a dihydrid cross is a cross between two dihybrids. Example is crossing YYRR and yyrr to get YyRr, YyRr is the dihybrid

Question 13

What is the law of independent assortment?

Answer 13

A law that states that two or more genes assort independently-each pair of alleles segregates independently of each other pair during gamete formation. APPLIES ONLY WHEN GENES ARE ON DIFFERENT CHROMOSOMES OR VERY FAR APART ON THE SAME CHROMOSOME

Question 14

What is incomplete dominance?

Answer 14

A situation where neither allele is completely dominant, and the offspring lie somewhere in between the two parental varieties

Question 15

What is codominance?

Answer 15

Each allele effects the offsprings phenotype in separate and distinguishable ways

Question 16

What is pleiotropy?

Answer 16

A property that most alleles have where they have multiple phenotypic effects

Question 17

What is epistasis?

Answer 17

The phenotypic expression of a gene at one locus alters that of a gene in a second locus

Question 18

What are quantitative characters?

Answer 18

Those that vary in the population along a continuum(example: skin color, height)

Question 19

What is polygenic inheritance?

Answer 19

The additive effect of 2 or more genes on a single phenotype

Question 20

What does it mean if a gene is multifactorial?

Answer 20

Many factors, both genetic and environmental, collectively influence the phenotype

Question 21

When is phenotypic range usually broadest?

Answer 21

When the characters are polygenic

Question 22

What is the chromosome theory if inheritance?

Answer 22

The theory that Mendelian genes have specific loci along chromosomes, and it is the chromosomes that undergo segregation and independent assortment

Question 23

What accounts for the independent assortment of alleles for two or more genes located on different chromosomes?

Answer 23

The behavior of non-homologous chromosomes

Question 24

What is a wild type?

Answer 24

The phenotype for a character most commonly observed in a natural population

Question 25

What are Mendel’s two laws of inheritance?

Answer 25

The law of independent assortment and the law of segregation