Characteristics and Genetics Flashcards
What chromosome in Alpha thalassemia and how many genes does it require?
Alpha Thalassemia genes are located on chromosome 16 and have 4 genes.
What chromosome in Beta-thalassemia and how many genes does it require?
Beta Thalassemia genes are located on chromosome 11 and have two genes.
What is Thalassemia?
Thalassemia is an inherited disease caused by genetic mutations affecting the haemoglobin.
What is an allele?
Alleles are different forms of the same gene located at the same point of homologous chromosomes.
What is pure breeding?
Pure breeding is when all individuals have the same genetic information for a characteristic, generation after generation.
What is a dominant trait?
A dominant trait is one that is observed in the outward appearance of a heterozygous individual. (capital letter)
What is heterozygous?
Heterozygous means to have two different alleles on homologous chromosomes.
What is homozygous?
Homozygous means to have two identical alleles on homologous chromosomes.
What is a recessive trait?
A recessive trait is one that remains hidden in the heterozygous condition and seen only in the homozygous condition. (little letter)
What is a genotype?
A genotype is genetic information carried by an individual.
What is a phenotype?
A phenotype is observable characteristics of the individual; what the genotype results in.
How is the sex of an offspring determined?
Male sperm determines the offspring’s sex because half their sperm carries the X chromosome and half carries the Y chromosome. If a sperm containing X chromosome fertilises the egg, the offspring will be female (XX).
What is a zygote?
A zygote is a cell formed by the fusion of two gametes, sperm and egg.
What are sex-linked genes?
Sex-linked genes are present on the sex chromosomes. Red-green colour blindness and haemophilia are examples of sex-linked characteristics.
What is a pedigree?
A pedigree is a diagram used to show patterns of inheritance over generations.
