Jessie Tran H Bio Chapter 13

Front 1

Patterns of Inheritance

Back 1

the pattern which the offspring gene gets from the parents

Front 2

Gene

Back 2

a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring

Front 3

Allele

Back 3

the versions of a gene that exist in more than 1 forms

Front 4

Homologous chromosome

Back 4

A couple of homologous chromosomes are a set of one maternal chromosome and one paternal chromosome that pair up with each other inside a cell during meiosis

Front 5

Dominant

Back 5

One in two traits of a gene, which tend to express when making the proteins

Front 6

Recessive

Back 6

One in two traits of a gene, which tend not to express when

Front 7

Principle of segregation

Back 7

The two members of a gene pair (alleles) segregate (separate) from each other in the formation of gametes. Half the gametes carry one allele, and the other half carry the other allele

Front 8

Genotype

Back 8

the genetic constitution of an individual organism.

Front 9

Phenotype

Back 9

the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment.

Front 10

Homozygous

Back 10

If an organism has two copies of the same allele, for example AA or aa, it is homozygous for that trait

Front 11

Heterozygous

Back 11

If the organism has one copy of two different alleles, for example Aa, it is heterozygous.

Front 12

Principle of independent assortment

Back 12

describes how different genes independently separate from one another when reproductive cells develop. Independent assortment of genes and their corresponding traits was first observed by Gregor Mendel in 1865 during his studies of genetics in pea plants.

Front 13

incomplete dominance

Back 13

refers to a genetic situation in which one allele does not completely dominate another allele, and therefore results in a new phenotype.

Front 14

codominance

Back 14

relationship between two versions of a gene. Individuals receive one version of a gene, called an allele, from each parent. If the alleles are different, the dominant allele usually will be expressed, while the effect of the other allele, called recessive, is masked

Front 15

Multiple alleles

Back 15

a gene can have more than two allelic forms segregating within a population. These genes are referred to as having multiple alleles.

Front 16

Polygenic inheritance

Back 16

determination of a particular characteristic, e.g. height or skin colour, by many genes (polygenes), each having a small effect individually

Front 17

Linked genes

Back 17

When two genes are located on the same chromosome they are called linked genes because they tend to be inherited together

Front 18

X-linked genes

Back 18

X-linked inheritance means that the gene causing the trait or the disorder is located on the X chromosome. Females have two X chromosomes, while males have one X and one Y chromosome.

Front 19

Nondisjunction

Back 19

the failure of one or more pairs of homologous chromosomes or sister chromatids to separate normally during nuclear division, usually resulting in an abnormal distribution of chromosomes in the daughter nuclei.

Front 20

Multifactorial/quantitative traits

Back 20

involving or dependent on a number of factors or causes.