inheritance Flashcards
define phenotype [3]
observable feature of an organism
e.g. the colour of someone’s eyes
phenotype of an organism depends on the genotype
define Monohybrid inheritance
inheritance of a single characteristic (e.g. eye colour)controlled by one pair of alleles
define genotype
genetic make-up of an organisms in terms of alleles present
genotype tells us which alleles are present i.e. which version of the gene the organism has
define homozygous
having two sets of identical alleles of a particular gene
define heterozygous
having two different alleles of a particular gene
when two homozygous individuals reproduce, their offspring will be
homozygous
when individuals with different genotypes reproduce
their offspring will have different genotypes
dominant allele is always written as
Capital letter
recessive allele always written as
lowercase letter
Albinism is an inherited condition in which pigment does not develop in the skin, hair and eyes.
The allele for albinism is recessive. What are the chances of albino parents having an albino child?
100%
Which structure will be found in the nucleus of a body cell in a woman?
X chromosome
How does a young race horse inherit its characteristics?
equally from its mother and father
In pea plants the allele for tall, T, is dominant to the allele for dwarf, t. Which cross would produce plants in the proportion of 1 tall: 1 dwarf?
Tt × tt
A pure-breeding plant with smooth stems was crossed with a heterozygous plant with hairy stems.
What will be the ratio of hairy : smooth stems in the resulting plants?
1 hairy : 1 smooth
Which statement about the human sex chromosomes is correct?
Everybody has at least one X chromosome.
