alleles Flashcards
What is an allele?
An allele is a variant form of a gene.
True or False: Alleles are located on chromosomes.
True
What are the two main types of alleles?
Dominant and recessive alleles.
Fill in the blank: A ________ allele masks the effect of a recessive allele.
dominant
What does homozygous mean?
Having two identical alleles for a particular gene.
What does heterozygous mean?
Having two different alleles for a particular gene.
Multiple Choice: Which of the following is an example of a homozygous genotype? A) AA B) Aa C) aa
A) AA
Multiple Choice: Which of the following represents a heterozygous genotype? A) BB B) Bb C) bb
B) Bb
True or False: An organism’s phenotype is influenced only by its genotype.
False
What is a phenotype?
The observable physical or biochemical characteristics of an organism.
Fill in the blank: The ________ is the genetic makeup of an organism.
genotype
What is the significance of alleles in inheritance?
Alleles determine the traits that are passed from parents to offspring.
True or False: An individual can have more than two alleles for a single gene.
True
What is codominance?
A situation where both alleles in a heterozygous genotype are fully expressed.
Multiple Choice: In a case of incomplete dominance, what is the phenotype of the offspring? A) Similar to one parent B) A blend of both parents C) Identical to both parents
B) A blend of both parents
What is the purpose of a Punnett square?
To predict the genotypes of offspring from a genetic cross.
Fill in the blank: The ________ of an allele refers to its position on a chromosome.
locus
True or False: All traits are controlled by a single pair of alleles.
False
What is polygenic inheritance?
Inheritance of traits that are controlled by multiple genes.
Multiple Choice: Which of the following best describes multiple alleles? A) Only two alleles exist for a gene B) More than two alleles exist for a gene C) Only one allele exists for a gene
B) More than two alleles exist for a gene
What is a test cross?
A cross between an individual with an unknown genotype and a homozygous recessive individual.
Fill in the blank: The ________ is the observable expression of a genotype.
phenotype
True or False: Alleles can only be dominant or recessive.
False
What are sex-linked traits?
Traits associated with genes located on the sex chromosomes.
