Punnett Sauare

Asexual Reproduction

a type of reproduction when offspring are created from one parent only

Sexual Reproduction

a type of reproduction where it tends to combine the genetic info of two individuals to create new individual

Trait

a specific characteristic that varies from one individual to another

Allele

these are different possibilities of a give trait

Two types of Alleles

Dominant & Recessive allele

Dominant Allele

these are alleles that are expressed frequently

Recessive Allele

these are alleles that are present yet rarely appear in a generation

Genotypes

is the genetic make up of an individual organism

Phenotype

a set of observable characteristics of an individual

Homozygous

refers to an organism that has two identical alleles for a particular trait

Heterozygous

an organism that has two different alleles for the same traits

Punnett square

used to determine the probability offspring will express a certain genotype

Reginald Crundall Punnett

is the person that devised punnet square

Types of cross

Monohybrid, Dihybrid, Polyhybrid

Monohybrid Cross

the hybrid of two individuals with homozygous & heterozygous genotypes. Red Hair v.s Black hair (allele). The crossing of an Allele

Dihybrid cross

the cross between different genes that differ in two observed traits. Gene crossing

Polyhybrid Cross

crossing of more than two traits of parents

Pedigree Analysis

a tool used to study the inheritance patterns of genetic traits

Francis Galton

he invented the pedigree analysis

Types of Pedigree analysis

Autosomal dominant & Recessive, X-linked dominant and recessive

Autosomal Dominant

occurs when a single copy of mutated genes is sufficient to cause the trait to be expressed

Autosomal Recessive

occurs when two copies of the mutated genes are required to express the trait

X-linked Dominant

type of inheritance that tends to affect females more than males

X-linked recessive

type of inheritance that tends to affect males more than females

Steps involved in Pedigree Analysis

Collect family info, construct pedigree, analyse the pedigree, interpret the results, follow up test

Limits & Challenges of pedigree analysis

Incomplete/inaccurate information, complex inheritance pattern, small sample size, non-paternity/non-maternity, limited diversity, environmental factors, ethical considerations