chapter thirteen/fourteen

Question 1

animal sexual life cycle

Answer 1

• only multicellular and zygote diploid
• only gametes haploid

Question 2

plant/algae sexual life cycle

Answer 2

• alternation of generations
• zygotes diploid, gametes haploid - unicellular
• sporophyte diploid stage, multicellular
• gametophyte haploid stage, multicellular

Question 3

sporophyte

Answer 3

• diploid stage, multicellular
• produces spores (haploid), divides mitotically, gametophyte

Question 4

gametophyte

Answer 4

• haploid stage, multicellular
• gives rise to gametes by mitosis, develops next sporophyte generation through fertilization

Question 5

fungi/protist sexual life cycle

Answer 5

• zygote only diploid, unicellular
• all multicellular = haploid (except some species)

Question 6

ancient theories of inheritance

Answer 6

Homunculus, blending, deGraaf

Question 7

Homunculus theory

Answer 7

a miniature human was already present in sperm that would increase in size

Question 8

blending theory of inheritance

Answer 8

many generations would blend toward a uniform population of individuals

Question 9

deGraaf theory of inheritance

Answer 9

egg of mom has mini human, sperm serves as activation

Question 10

character

Answer 10

a hereditable feature
- ear shape, flower color

Question 11

trait

Answer 11

a variant for a character
- attached ear lobes, purple flower

Question 12

true (pure) breeding

Answer 12

will always produce identical offspring with regard to character under study
- homozygous for genes

Question 13

self-pollinating

Answer 13

plant which produces pollen to fertilize its eggs

Question 14

hybridization

Answer 14

crossing of 2 pure-breeding parents to form a hybrid (mixture)

Question 15

3 generations of Mendel’s genetics

Answer 15

1. P
2. F1
3. F2

Question 16

P generation

Answer 16

parental generation, true bred
- hybridized them (purple x white)

Question 17

F1 generation

Answer 17

first filial generation, hybrid offspring
- all purple

Question 18

F2 generation

Answer 18

second filial generation, result from hybrids (self-pollinating for plants) of F1
- purple & white (3:1)

Question 19

ex. of reciprocal cross

Answer 19

white male X purple female or purple male X white female

Question 20

Law of Segregation
(Mendel’s 1st Law)

Answer 20

2 alleles of a gene separate during gamete formation
- only 1 allele per gamete
- occurs in meiosis I unless cross-over occurred, then can be meiosis II

Question 21

phenotypic ratio of F2

Answer 21

3 purple : 1 white

Question 22

genotypic ration of F2

Answer 22

1 PP : 2 Pp : 1 pp

Question 23

what do alternative versions of genes account for

Answer 23

variations in inherited characters

Question 24

allele

Answer 24

different versions of a character gene, each allele is a gene, produces a trait

Question 25

where are alleles located

Answer 25

on homologous chromosomes - one maternal in origin, one paternal - same locus (location) on chromosome

Question 26

gene

Answer 26

section of DNA that codes for an RNA molecule - if an mRNA is made, gene codes for a protein

Question 27

for each character, an organism inherits 2 alleles, one from each...

Answer 27

parent

Question 28

dominant allele

Answer 28

- observable in organism's appearance and heterozygous phenotype

Question 29

recessive allele

Answer 29

- has no noticeable effect on organisms appearance unless completely recessive

Question 30

when do 2 alleles for a hereditable character separate

Answer 30

gamete formation - Law of Segregation, 1 allele/gene

Question 31

homozygous

Answer 31

having 2 identical alleles for a gene

Question 32

heterozygous

Answer 32

having 2 different alleles for a gene

Question 33

phenotype

Answer 33

dominant or recessive - actual physical appearance due to gene expression - 3 purple : 1 white

Question 34

genotype

Answer 34

composition of genes (alleles) of given trait - genetic makeup - 1 PP : 2 Pp : 1 pp

Question 35

what is used to work genetic crosses

Answer 35

Punnett square

Question 36

test cross

Answer 36

cross dominant phenotype with unknown genotype (P-) with homozygous recessive (pp)

Question 37

Law of Independent Assortment (Mendel's 2nd Law)

Answer 37

each pair of alleles segregates independently of other pairs during gamete formation

Question 38

monohybrids

Answer 38

heterozygous for 1 character (could be F1 generation above)

Question 39

dihybrids

Answer 39

heterozygous for 2 characters

Question 40

Mendel's dihybrid cross ratio

Answer 40

self-crossing dihybrids (F1) to get an F2 - 9:3:3:1