Genetics Test Flashcards

Questions and Answers

The form of a gene that is always expressed if present is the ___ form.

dominant

What are the expected phenotypic results when two heterozygous purple-flowering pea plants are crossed, given that purple is dominant over white?

create a punnett square

What law best explains why an organism with 'Tt' will show only the dominant phenotype?

Law of Dominance

If an organism inherits one dominant allele and one recessive allele for eye color, their genotype would be?

heterozygous Signup and view all the answers

What is the chance that any of the children of two parents with the genotype Gg will inherit a recessive genetic disorder?

25% Signup and view all the answers

Which Mendelian law of inheritance states that organisms inherit two copies of each gene and donate one copy to each of their offspring?

law of segregation Signup and view all the answers

What percent chance does the offspring have for red feathers when a homozygous dominant and a homozygous recessive bird mate?

create a punnett square Signup and view all the answers

What must be the genotypes of a rough coat boar and a soft coat sow that produce 50% rough coat and 50% smooth coat piglets?

Rr × rr Signup and view all the answers

What would the genotypic ratio of the offspring be from two heterozygous parents who have a dominant allele A for brown eyes and a recessive allele for blue eyes?

create a punnett square Signup and view all the answers

What is the genotype for TT?

Homozygous Signup and view all the answers

What is the genotype for Tt?

heterozygous Signup and view all the answers

What is the genotype for tt?

homozygous Signup and view all the answers

If square is dominant over round, what are the phenotypes for the genotypes SS, Ss, and ss?

square, square, round Signup and view all the answers

What must you know when practicing punnett squares?

know how to find genotype, phenotype, and find how many offspring would have traits Signup and view all the answers

For an XX female to express a recessive sex-linked trait, she must have?

two recessive alleles Signup and view all the answers

What type of trait occurs in a continuous range due to many gene interactions?

polygenic trait Signup and view all the answers

Which pattern of inheritance explains the common inheritance of red hair and freckles?

Linked Genes Signup and view all the answers

Which pair of genes in a diagram would be most likely to be inherited together?

the two closest to each other Signup and view all the answers

What is the only blood type not possible in the children of a man with Type A blood and a woman with Type AB blood?

create punnett squares to answer this question Signup and view all the answers

What type of inheritance is shown when a cross between a red-haired and a white-haired purebred animal produces offspring with both hair colors?

co dominance Signup and view all the answers

In a cross between tropical fish where all male offspring have long tails while none of the females do, this trait is considered?

sex linked Signup and view all the answers

What type of dominance occurs in a cross between a white horse and a chestnut horse producing all light brown horses?

incomplete dominance Signup and view all the answers

What type of inheritance is shown when a cross between tall and short sunflowers results in varying heights?

polygenic inheritance Signup and view all the answers

What is the probability of a colorblind male being born to a color-blind mother and a color-normal father?

show a punnett square to answer this question: remember XX and XY Signup and view all the answers

Mutations can be caused by all of the following except?

Global warming Signup and view all the answers

In order for a mutation to be passed on from parent to offspring, it must occur in?

gametes Signup and view all the answers

What is it called when a mutation only changes the nucleotide sequence for a single protein?

gene mutation Signup and view all the answers

What kind of mutation occurred in the sex chromosome of an individual with the genotype XXY?

nondisjunction Signup and view all the answers

Study Notes

Genetic Terminology

Dominant form of a gene is expressed if present in an organism's genotype.
Heterozygous genotype occurs when an organism inherits one dominant and one recessive allele.
Homozygous indicates having two identical alleles for a trait, while heterozygous refers to different alleles.

Mendelian Inheritance Laws

Law of Dominance: An organism with a heterozygous genotype (like 'Tt') will display the dominant phenotype.
Law of Segregation: Each organism inherits two copies of each gene and donates one to their offspring.

Punnett Squares

Used to predict the phenotypic and genotypic ratios of offspring in genetic crosses.
Crosses of homozygous dominant and homozygous recessive parents yield predictable results based on dominant and recessive traits.

Genetic Ratios and Traits

A genetic cross involving two heterozygous individuals often results in a phenotypic ratio of 3:1 for dominant and recessive traits.
Polygenic traits, like human height, arise from the interaction of multiple genes, resulting in a continuous range of expression.
Co-dominance occurs when both alleles are expressed equally, while incomplete dominance results in a blend of traits.

Sex-linked Traits

Recessive sex-linked traits require two recessive alleles for females (XX) to be expressed.
Male offspring of a colorblind mother and a normal vision father have a probability of being colorblind, requiring analysis through Punnett squares.

Mutations

Mutations affecting gametes can be passed from parent to offspring.
Types of mutations include gene mutations that alter nucleotide sequences of a single gene and nondisjunction, which can lead to disorders such as Down syndrome.

Miscellaneous Genetic Concepts

Disorders can arise from nondisjunction events, specifically in autosomes or sex chromosomes.
Linked genes are inherited together more frequently if they are located close to one another on the same chromosome.
Genetic crosses can demonstrate specific inheritance patterns based on the dominance or interaction of alleles.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Test your knowledge of genetics with these flashcards covering key terms and concepts. Each card includes definitions and examples, helping you to better understand genetic principles such as dominance and the law of segregation. Perfect for students studying genetics or preparing for exams.