Ch 11-1 Flashcards
What is a character in genetics?
A heritable feature that can vary among individuals (e.g., flower color).
What is a trait?
specific version of a character, like purple or white flower color.
Define true breeding
Organisms that produce offspring identical to themselves when self-pollinated.
What is hybridization?
The crossing of two true-breeding plants with different traits.
Alleles meaning
Different versions of a gene that account for variations in a trait.
What is a dominant allele?
An allele that masks the effect of a recessive allele in a heterozygous individual.
What is a recessive allele?
An allele whose effects are masked in the presence of a dominant allele
What is the Law of Segregation?
Alleles separate during gamete formation, with each gamete receiving only one allele per gene.
What is the Law of Independent Assortment?
Genes for different traits can separate independently during gamete formation.
Define phenotype.
The observable traits or appearance of an organism.
Define genotype
The genetic makeup or combination of alleles in an organism.
What is a homozygote?
An individual with two identical alleles for a gene.
Whats heterozygote
An individual with two different alleles for a gene.
What is test cross
A cross between an individual with an unknown genotype and a homozygous recessive individual.
Purpose of punnett square
To predict the genotype and phenotype ratios of offspring from a genetic cross.
Which term describes a heritable feature that varies among individuals?
A) Trait
B) Character
C) Gene
D) Allele
B
What are alternate versions of a gene called?
A) Genotypes
B) Traits
C) Alleles
D) Phenotypes
C
In Mendelian genetics, what is the dominant allele?
A) An allele that always shows its effect
B) An allele that is hidden in the presence of another
C) A trait passed only from fathers
D) The most common trait in a population
A
What is the ratio Mendel observed in F2 generation monohybrid crosses for dominant to recessive traits?
A) 1:1
B) 2:1
C) 3:1
D) 4:1
C
Which of the following is a phenotype?
A) Bb
B) Blue eyes
C) bb
D) Chromosome
B
What principle explains that alleles separate during gamete formation?
A) Law of Independent Assortment
B) Law of Dominance
C) Law of Segregation
D) Law of Recombination
C
What kind of cross helps determine the genotype of an organism with a dominant phenotype?
A) Monohybrid cross
B) Testcross
C) Dihybrid cross
D) Self-pollination
B
Which genotype represents a homozygous recessive individual?
A) AA
B) Aa
C) aa
D) Bb
C
What does a Punnett square show?
A) The possible genotypes and phenotypes of offspring
B) The DNA sequence of a gene
C) Chromosomal structure
D) Protein synthesis process
A
Mendel’s work with pea plants led to the development of:
A) Evolution theory
B) Cell theory
C) Laws of Inheritance
D) Photosynthesis
C
In a dihybrid cross, how many possible combinations of alleles are there if independent assortment occurs?
A) 1
B) 2
C) 3
D) 4
D
What does it mean if genes are “linked”?
A) They are on different chromosomes
B) They are far apart on the same chromosome
C) They are inherited together because they are close on the same chromosome
D) They mutate together
C
What is polygenic inheritance?
A) A single gene affecting multiple traits
B) Multiple genes affecting one trait
C) Two traits being inherited together
D) Linked genes on the same chromosome
B
What type of inheritance pattern results in a blend of traits, like red and white flowers making pink?
A) Complete dominance
B) Codominance
C) Incomplete dominance
D) Pleiotropy
C
Which rule is used when calculating the probability of two independent events both happening?
A) Addition rule
B) Subtraction rule
C) Multiplication rule
D) Division rule
C
True or False: Mendel’s Law of Segregation states that alleles separate during gamete formation.
T
True or False: In a testcross, the unknown genotype is crossed with a homozygous dominant individual.
F
True or False: Traits inherited through polygenic inheritance are influenced by multiple genes.
T
True or False: A genotype with two identical alleles is heterozygous.
F
True or False: The Law of Independent Assortment applies to genes on the same chromosome close together.
F
True or False: Codominance results in both alleles being expressed fully, like in a spotted cow.
T
True or False: In a monohybrid cross, the F2 generation shows a 3:1 ratio of dominant to recessive traits.
T
True or False: A phenotype is the genetic makeup of an individual.
F
True or False: Linked genes are usually inherited together because they are close on the same chromosome.
T
True or False: Mendel’s experiments proved that traits blend in offspring, creating intermediate phenotypes.
F
