Genetics Flashcards
What is a Gene
A section of DNA that codes for a particulatr trait if characteristic.
What is an Allele
A different form of a gene that codes for a different version of a characteristic.
What is a dominant allele
An allele that will be expressed if one or both alleles are of this type e.g. Hh or HH.
What is a recessive allele
A recessive allele is an allele that will only be expressed when both alleles are of this type e.g. hh
What is a genotype
A description of the pair of alleles present for a characteristic.
What is a phenotype
The physical expression of the alleles.
What does homozygous mean
If alleles in a matching pair are the same, they are called homozygous alleles e.g. yellow petal - yellow petal
What does heterozygous mean
If alleles in a matching pair are different, they are called heterozygous alleles e.g. red petals - yellow petal
What does DNA stand for
Deoxyribonucleic acid
How many pairs of chromozones does the human body have in every cell
23 pairs
What is a chromozone
A chromosome is a coiled structure of DNA found in the nucleus of cells made from many genes.
What type of allele is cystic fibrosis
Recessive
What type of allele is ploydactyly
Dominant
What is genetic engineering
In genetic engineering, genes from the chromosomes of humans and other organisms can be cut out using emzymes and transferred to cells of other organisms
What is selective breeding
When you breed two animals together to get the desired offspring
