Mutations
What is a mutation?
A change in the DNA sequence
What is a genotype ?
The genetic makeup of an organism
The genes
Which type of trait is expressed when at least one dominant allele is present
Dominant Trait
What does homozygous mean?
Having two identical alleles for a trait
What is a Punnett square used for
Predicting the probability of offspring traits
What type of mutation has no effect on the organism?
Neutral mutation
What is a phenotype?
The physical traits or appearance of an organism
what you can physically see
What symbol is typically used for a dominant allele?
A capital letter (e.g. A)
What does heterozygous mean?
Having two different alleles for a trait
If both parents are Aa, what are the possible genotypes of their offspring?
AA, Aa, aa
What kind of mutation can improve an organism survival?
Beneficial mutation
If a plant has the genotype Tt, what is its phenotype if T is tall and t is short?
Tall
What symbol is used for a recessive allele?
a lowercase letter (e.g, a)
Is AA homozygous or heterozygous?
Homozygous
what percentage of offspring will be homozygous recessive if we crossed Aa and Aa
25%
What kind of mutation can cause diseases or disorders?
Can two organisms have the same phenotype but different genotypes
Yes
If both parents are heterozygous for a trait, what is the chance their child will show the recessive trait? Percentage!
25%
Is Qq is homozygous or heterozygous?
Heterozygous
What is the phenotype ration from an Aa and Aa cross?
___ dominant : __ recessive
3 dominant : 1 recessive
Give an example of a beneficial mutation in humans
lactose tolerance, Sickle cell trait, malaria resistance, and high altitude adaption
What genotype combinations result in a recessive phenotype?
Homozygous recessive (e.g tt)
Give an example of a dominant human trait
Brown eyes
Can a heterozygous organism express a recessive trait?
No, unless the recessive trait is codominant or incomplete dominant.
If one parent is AA and the other is aa, what will all the offspring be?
All heterozygous ! Aa