What is a genotype? The entire genetic code and composition of an organism
What is a gene? A length of DNA that codes for a particular protein
What is an allele? An alternate version of a gene that determines the way the
gene expresses itself and what phenotype it produces
What is a phenotype? The characteristic of an organism, as a result of the
interaction between the expression of one or more alleles and the environment
What is a locus? The position of a gene on the chromosome
What does dominant mean? Only one of the alleles is required to express the
phenotype
What does recessive mean? Both copies of the allele must be present in the
homologous pair for the phenotype to be expressed
What does codominant mean? Two alleles will contribute to the phenotype, and the
phenotype is either a blend of two or both are expressed
How do you choose a letter for the alleles? You choose the first letter of one
of the contrasting characteristics for example Gg for green/yellow in peas
What is dihybrid inheritance? When the inheritance of two genes located on
different chromosomes is investigated
How many letters are there in the genotype of a dihybrid inheritance? 4
How many letters are there in the gametes of a dihybrid inheritance? 2
How many possible gametes are there for a heterogenous organism in a dihybrid
inheritance? 4
What does a dihybrid inheritance look like for a F2? "<img src=""paste-
69b3ad657d477491eb8a72249db946438a6aaf59.jpg"">"
What is multiple alleles defined as? When there are multiple alleles, and only
two of which can be present at the locus of the gene
What does a codominance monohybrid cross look like? "<img src=""paste-
98527d07f97f802621cf345e67c2077dabffc8ca.jpg"">"
What is the chi-squared test used for? Categorical data
What is sex linkage defined as? When a gene is carried on the X
chromosome
What does a sex-linked gene controlled by a recessive allele make more likely and
why? If a gene is on the X chromosome and the allele for the characteristic is
recessive, it makes it more likely that males will express the allele as the male
only requires one copy of the allele for it to be expressed whereas females need
two copies of the allele
What does a sex-linked cross look like? "<img src=""paste-
9141291e41b4a2f83ed61a07a727069157d26305.jpg"">"
What is the formula for the chi squared test? "<img src=""paste-
732017e225dde05f71fa5af6952029ecd8ae71ab.jpg"">"
How do you calculate the degrees of freedom for chi squared? n-1
What is autosomal linkage defined as? When both genes being investigated are on
the same chromosome and so have a tendency to be kept together on the same
chromosome during independent segregation in meiosis
How many gametes are there involved in autosomal linkage and why? Only 2, and
that is because there is only one homologous pair involved, so only two gametes can
be formed, as both genes are on the same chromosome
What is epistasis defined as? Where the allele of one gene affects or masks the
expression of another in the phenotype
In the example where gene A is fur banding, where the dominant is black bands, and
gene B is pigment, and the dominant is pigment, what would the genotype AABB
produce? A brown colour, as despite the black pigment, the banding means the
colour comes out as brown
"In the example where gene A is fur banding, where the dominant is black bands, and
gene B is pigment, and the dominant is pigment, what would the genotype
aaBB <span style=""color: var(--field-fg); background: var(--field-
bg);"">produce?</span>" Black, as the black pigment is present, and the banding is
uniform, producing a true black fur colour
In the example where gene A is fur banding, where the dominant is black bands, and
gene B is pigment, and the dominant is pigment, what would the genotype AAbb
What is a gene? A length of DNA that codes for a particular protein
What is an allele? An alternate version of a gene that determines the way the
gene expresses itself and what phenotype it produces
What is a phenotype? The characteristic of an organism, as a result of the
interaction between the expression of one or more alleles and the environment
What is a locus? The position of a gene on the chromosome
What does dominant mean? Only one of the alleles is required to express the
phenotype
What does recessive mean? Both copies of the allele must be present in the
homologous pair for the phenotype to be expressed
What does codominant mean? Two alleles will contribute to the phenotype, and the
phenotype is either a blend of two or both are expressed
How do you choose a letter for the alleles? You choose the first letter of one
of the contrasting characteristics for example Gg for green/yellow in peas
What is dihybrid inheritance? When the inheritance of two genes located on
different chromosomes is investigated
How many letters are there in the genotype of a dihybrid inheritance? 4
How many letters are there in the gametes of a dihybrid inheritance? 2
How many possible gametes are there for a heterogenous organism in a dihybrid
inheritance? 4
What does a dihybrid inheritance look like for a F2? "<img src=""paste-
69b3ad657d477491eb8a72249db946438a6aaf59.jpg"">"
What is multiple alleles defined as? When there are multiple alleles, and only
two of which can be present at the locus of the gene
What does a codominance monohybrid cross look like? "<img src=""paste-
98527d07f97f802621cf345e67c2077dabffc8ca.jpg"">"
What is the chi-squared test used for? Categorical data
What is sex linkage defined as? When a gene is carried on the X
chromosome
What does a sex-linked gene controlled by a recessive allele make more likely and
why? If a gene is on the X chromosome and the allele for the characteristic is
recessive, it makes it more likely that males will express the allele as the male
only requires one copy of the allele for it to be expressed whereas females need
two copies of the allele
What does a sex-linked cross look like? "<img src=""paste-
9141291e41b4a2f83ed61a07a727069157d26305.jpg"">"
What is the formula for the chi squared test? "<img src=""paste-
732017e225dde05f71fa5af6952029ecd8ae71ab.jpg"">"
How do you calculate the degrees of freedom for chi squared? n-1
What is autosomal linkage defined as? When both genes being investigated are on
the same chromosome and so have a tendency to be kept together on the same
chromosome during independent segregation in meiosis
How many gametes are there involved in autosomal linkage and why? Only 2, and
that is because there is only one homologous pair involved, so only two gametes can
be formed, as both genes are on the same chromosome
What is epistasis defined as? Where the allele of one gene affects or masks the
expression of another in the phenotype
In the example where gene A is fur banding, where the dominant is black bands, and
gene B is pigment, and the dominant is pigment, what would the genotype AABB
produce? A brown colour, as despite the black pigment, the banding means the
colour comes out as brown
"In the example where gene A is fur banding, where the dominant is black bands, and
gene B is pigment, and the dominant is pigment, what would the genotype
aaBB <span style=""color: var(--field-fg); background: var(--field-
bg);"">produce?</span>" Black, as the black pigment is present, and the banding is
uniform, producing a true black fur colour
In the example where gene A is fur banding, where the dominant is black bands, and
gene B is pigment, and the dominant is pigment, what would the genotype AAbb
