Alleles can produce dominant and recessive traits

Alleles can produce dominant and recessive traits

1.6 Alleles can produce dominant or recessive traits

Multiple Choice

What is the label for A?

• Phosphate

• Nitrogen base pairs

• Deoxyribose (sugar)

• Hydrogen Bonds

Multiple Choice

What is the label for B?

• Hydrogen bonds

• Deoxyribose (sugar)

• Phosphate

• Nitrogen base pairs

Multiple Choice

What is the label for C?

• Nitrogen base pairs

• Phosphate

• Hydrogen bonds

• Deoxyribose (Sugar)

Multiple Choice

What is the label for D?

• Phosphate

• Deoxyribose (Sugar)

• Nitrogen base pairs

• Hydrogen bonds

What is an Allele?

• An Allele: A version of a gene. Each person inherits one allele from each parent

Alleles

• You inherit genes from your parents, eg. Eye colour.

• Each version of the same gene, at the same position of a chromosome is called an allele

Definitions

Homozygous: Having two identical alleles for a particular trait.

Heterozygous: Having two different alleles for a particular trait: a carrier for the recessive trait.

Homozygous and Heterozygous Alleles

• If you have two identical alleles for a trait or characteristic, than you are said to be homozygous for that trait. For example two blue eye alleles.

  
  

• If you have two different alleles for the same trait, then you are heterozygous for the trait. For example a blue eye allele and a brown eye allele. 

Definition

Phenotype: The physical characteristics that result from the interaction between the genotype and the environment.  

Genotype: the combination of alleles for a particular trait. 

Multiple Choice

TT and Tt are is

• Dominant

• Recessive

• Both

• None

Multiple Choice

Recessive alleles are written with:

• Upper case always

• Lower case always

Multiple Choice

Dd is

• Dominant

• Recessive

• Both

• None

Multiple Choice

DD is

• Dominant

• Recessive

• Both

• None

Multiple Choice

dd is

• Dominant

• Recessive

• Both

• None

Multiple Choice

The Physical characteristics of an organism that we can observe or see.

• Alleles
• Genes
• Genotype
• Phenotype