Chapter 14 Biology Review

Front 1

Character

Back 1

A heritable feature that varies among individuals, such as flower color

Front 2

Trait

Back 2

Each variant for a character, such as purple or white color for flowers

Front 3

Planned breeding

Back 3

Organisms are bred and results are analyzed (such as fruit flies, pea pods). Produces large number of offspring, short life cycle, convenient to contain.

Front 4

Pedigree analysis

Back 4

examines history of inheritance of traits, used for when controlled breeding cannot be done (humans)

Front 5

Genes

Back 5

The segment of DNA that codes for protein

Front 6

True breeding

Back 6

when plants self-pollinate, all of their offspring are of the same variety

Front 7

P Generation

Back 7

True breeding parents

Front 8

F1 Generation

Back 8

First filial offspring

Front 9

F2 Generation

Back 9

Second filial offspring

Front 10

Phenotypes of Mendel's F1

Back 10

All purple

Front 11

Phenotypes of Mendel's F2

Back 11

3:1 Dominant to recessive (purple to white)

Front 12

Allele

Back 12

different forms of a gene

Front 13

Locus

Back 13

physical location of a gene on a chromosome

Front 14

Homozygous

Back 14

Two alleles are the same

Front 15

Heterozygous

Back 15

Two alleles are different

Front 16

Dominant allele

Back 16

Trait produced in heterozygous and homozygous conditions

Front 17

Recessive allele

Back 17

Trait produced only in homozygous conditions

Front 18

Phenotype

Back 18

Physical traits

Front 19

Genotype

Back 19

genetic makeup expressed in letters

Front 20

Law of Segregation

Back 20

members of a pair of genes separate during gamete formation (an offspring organism gets 2 alleles, 1 from each parent)

Front 21

Monohybrids

Back 21

All of F1 progeny produced in crosses of true-breeding parents

Front 22

Monohybrid cross

Back 22

Cross involving genes at 1 locus, a cross between heterozygotes

Front 23

Dihybrids

Back 23

Individuals heterozygous for two characters

Front 24

Dihybrid cross

Back 24

Cross between individuals with heterozygous genotypes for two alleles

Front 25

Test cross

Back 25

A cross done to determine the genotype of a parent with a dominant phenotype

Front 26

Tester

Back 26

Homozygous recessive

Front 27

If parent is Pp (test cross)

Back 27

Offspring will be 50/50 on phenotypes

Front 28

If parent is PP (test cross)

Back 28

Offspring wil all exhibit dominant phenotype

Front 29

Law of Independent Assortment

Back 29

Genes for a pair of traits are distributed independently of one another when gametes are formed (only occurs when genes are on separate chromosomes)

Not all genes exhibit it

Front 30

Phenotype of F2 Dihybrid Cross

Back 30

9:3:3:1

Front 31

Codes for a functional protein

Back 31

Dominant allele

Front 32

Codes for a non-functional protein

Back 32

Recessive allele

Front 33

Complete dominance

Back 33

YY and Yy have same phenotype

Front 34

Codominance

Back 34

Both alleles are expressed, such as A and B making AB type blood

Front 35

Incomplete dominance

Back 35

Heterozygote has a phenotype intermediate between homozygous phenotypes

Front 36

Tay-Sachs disease

Back 36

brain cells cannot metabolize certain lipids

Front 37

Pleiotropy

Back 37

When a gene has multiple phenotypic effects

Front 38

Epistasis

Back 38

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

Front 39

In terms of disease, exhibit dominant phenotype yet have one recessive allele

Back 39

Carrier

Front 40

Cystic fibrosis

Back 40

Recessive genetic disease, lack of membrane protein to transport chloride ions between cells and extracellular fluid

Front 41

Huntington's Disease

Back 41

Lethal, caused by dominant allele that doesn't have phenotypic effect until later age