Heredity Flashcards
Pure dominant genotype
BB
Pure recessive genotype
bb
Hybrid genotype
Bb
Heterozygous Jeanpair
Bb
Homozygous Jean pair
BB or bb
Dominant allele
B
Recessive allele
b
When a pure dominant trait is crossed with a pure recessive trait, which trait will express itself and all the offspring? Dominant or recessive? Give an example.
Dominant because dominant alleles cover the recessive and all the offspring will have a heterozygous genotype
What type of genotype is necessary for a recessive trait to appear
Pure recessive (bb)
If a person is a carrier for disease but does not have the disease, how would you describe the condition of the alleles
Heterozygous/hybrid
What is a gene?
A small section of DNA that carries a specific code for a trait
Different forms of a gene are called?
Alleles
List the following in order from smallest to largest: chromosome, allele, nucleus, nitrogen base pair (adenine & thymine), DNA
Nitrogen base pair, allele (gene) DNA, chromosome, nucleus
What is a pedigree used for?
To trace the inheritance of a specific trait in a family
On a pedigree what did the squares represent?
Male
On a pedigree what does it mean if the circle is half shaded?
Carrier but does not express the recessive trait
What is the difference between genetic engineering and selective breeding?
Genetic engineering is the actual DNA is altered in someway by inserting a needed Jane directly into the persons cells
Selective breeding is specific traits are selected in the parents in order to ensure they are passed on in the offspring and the genes are not actually altered
List some positive uses for selective breeding
The traits can be easily predicted. You can produce offspring that can serve a specific purpose
List some benefits of genetic engineering and give specific examples
Make medication and treat diseases: create bacterial cells that produce important human proteins such as insulin
cure human genetic disorders: use virus to deliver the gene to cells in the lungs of someone with cystic fibrosis
What is the purpose of DNA in the nucleus of a cell?
To carry the codes that contain information about the proteins needed to form specific proteins needed to build certain traits that the organism can express
What is incomplete dominance?
When both alleles express themselves as a blend and neither allele dominates the other allele
