2.1 - 2.4

Question 1

blending theory

Answer 1

predominant hereditary theory around time of mendle (mit to late 19th century)

viewed the traits of progeny as a mixture of the characteristics possessed byt the two parental forms. Under this theory, progeny were believed to display characteristics that were approximately intermediate between those of the parents.

Question 2

artificial cross-fertilization

Answer 2

in the case of mendel and his peas:

first, he emasculated developing pea flowers by cutting off the nascent anthers, making the plants incapable of self-pollination, but the ovules could still be fertilized by cross-fertilization with pollen from another plant.

Question 3

controlled genetic cross

Answer 3

using artificial cross-fertilization with organism that will likely produce an informative result

Question 4

pure-breeding strains (true breeding strains)

Answer 4

strains that consistently produce a single phenotype without variation

Question 5

Parental generation plants (P-generation plants)

Answer 5

the first two pure breeding plants crossed in a particular lineage

Question 6

first filial generation (F1 generation)

Answer 6

offspring of P-generation

and so on and so fourth for second and third filial generations

Question 7

replicate crosses

Answer 7

repeating the same cross multiple times

Question 8

reciprocal crosses

Answer 8

the same genotypes are crossed but the sexes of the donating parents are switched.
(i.e. the plant providing the ovule in the first cross is used as a source of pollen in the reciprocal cross.

Question 9

test crosses

Answer 9

a cross in which one parent’s genotype is unknown, while the other is known

Question 10

what 3 consistent features id Mendel’s results reveal?

Answer 10

1) dominance of one phenotype over the other in the F1 generation
2) reemergence of the recessive phenotype in the F2 generation
3) a ratio of approximately 3:1 (dominant:recessive) among F2 phenotypes

Question 11

particulate inheritance

Answer 11

proposed by gregor mendel

proposes that each plant (or sexually reproducing organism more generally) carries two particles of heredity for each trait. A plant receives one unit of heredity in the egg and the second unit in pollen. Each parental plant passes one of its two particles to offspring during reproduction.

Question 12

homozygous genotype

Answer 12

meaning that the two alleles carried by an organism are identicle.
pure breeding = homozygous

Question 13

heterozygous genotype

Answer 13

two different alleles make up the genotype

Question 14

monohybrid cross

Answer 14

a term referring to a cross between two organisms that have the same heterozygous genotype for one gene.

Question 15

what was the genotypic ratio expressed in mendel’s plants F2 generation

Answer 15

1 homozygous dominant: 2 heterozygous : 1 homozygous recessive

Question 16

The law of segregation (Mendel’s first law)

Answer 16

The two alleles for each trait will separate (segregate) from one another during gamete formation, and each allele will have an equal probability (1/2) of inclusion in a gamete. Random union of gametes at fertilization will unite one gamete from each parent to produce progeny in ratios that are determined by chance.

Question 17

dihybrid cross

Answer 17

a cross between two organisms that differ for two traits

Question 18

the law of independent assortment

Mendel’s second law

Answer 18

During gamete formation, the segregation of alleles at one locus is independent of the segregation of the segregation of alleles at another locus.

Question 19

trihybrid cross

Answer 19

a cross involving three traits

in the book example’s case, seed shape, seed color, flower color

Question 20

conditional probability

Answer 20

the probability of an evevent contingent upon a certain additional circumstance or set of circumstances

Question 21

autosomal inheritance

Answer 21

refers to the transmission of genes that are carried on autosomes, the chromosomes found in both males and females

Question 22

pedigree

Answer 22

a family tree
circles = females
squares = males

line through = deceased
filled = expressed phenotype