Podcast
Questions and Answers
What phenotype is exhibited by heterozygous individuals in incomplete dominance for hair texture?
What phenotype is exhibited by heterozygous individuals in incomplete dominance for hair texture?
When two wavy haired individuals mate, what genotype combinations can possibly be produced in their offspring?
When two wavy haired individuals mate, what genotype combinations can possibly be produced in their offspring?
If a roan cow (RW) mates with a white bull (WW), what percentage of the offspring will be roan?
If a roan cow (RW) mates with a white bull (WW), what percentage of the offspring will be roan?
What alleles must be present for a calf to be red when a roan cow mates with a white bull?
What alleles must be present for a calf to be red when a roan cow mates with a white bull?
Signup and view all the answers
What is the probability that a parent with Type AB blood can have a child with Type O blood?
What is the probability that a parent with Type AB blood can have a child with Type O blood?
Signup and view all the answers
What does it mean for an allele to be completely dominant?
What does it mean for an allele to be completely dominant?
Signup and view all the answers
What is an example of codominance?
What is an example of codominance?
Signup and view all the answers
What is meant by being a carrier in genetics?
What is meant by being a carrier in genetics?
Signup and view all the answers
What distinguishes a polygenic trait?
What distinguishes a polygenic trait?
Signup and view all the answers
Which of the following is considered a multifactorial trait?
Which of the following is considered a multifactorial trait?
Signup and view all the answers
What characterizes continuous traits?
What characterizes continuous traits?
Signup and view all the answers
Why are males generally more affected by sex-linked diseases than females?
Why are males generally more affected by sex-linked diseases than females?
Signup and view all the answers
What is the primary purpose of a pedigree chart in genetics?
What is the primary purpose of a pedigree chart in genetics?
Signup and view all the answers
When two heterozygous tall pea plants (Tt) are crossed, what percentage of offspring is expected to be homozygous dominant (TT)?
When two heterozygous tall pea plants (Tt) are crossed, what percentage of offspring is expected to be homozygous dominant (TT)?
Signup and view all the answers
In the cross between a homozygous tongue roller and a heterozygous tongue roller, what is the expected genotype of the offspring?
In the cross between a homozygous tongue roller and a heterozygous tongue roller, what is the expected genotype of the offspring?
Signup and view all the answers
If a man and a woman both have attached earlobes, what is the chance of having a child with free earlobes?
If a man and a woman both have attached earlobes, what is the chance of having a child with free earlobes?
Signup and view all the answers
In the cross of two heterozygous individuals for a widow's peak hairline, what is the expected phenotypic ratio?
In the cross of two heterozygous individuals for a widow's peak hairline, what is the expected phenotypic ratio?
Signup and view all the answers
What are the possible genotypes of offspring from a cross between a red flowered plant (RR) and a pink flowered plant (Rr) in four o'clock plants?
What are the possible genotypes of offspring from a cross between a red flowered plant (RR) and a pink flowered plant (Rr) in four o'clock plants?
Signup and view all the answers
What is the expected phenotypic ratio when crossing a pink four o'clock plant and a red one?
What is the expected phenotypic ratio when crossing a pink four o'clock plant and a red one?
Signup and view all the answers
Which genotype represents a white-flowered four o'clock plant?
Which genotype represents a white-flowered four o'clock plant?
Signup and view all the answers
What is the genotypic ratio (RR : Rr : rr) when a pink and a white four o'clock plant are crossed?
What is the genotypic ratio (RR : Rr : rr) when a pink and a white four o'clock plant are crossed?
Signup and view all the answers
What is the genotype ratio for male offspring from a cross between a heterozygous female and a red-eyed male?
What is the genotype ratio for male offspring from a cross between a heterozygous female and a red-eyed male?
Signup and view all the answers
In the context of hemophilia, if a man with hemophilia mates with a homozygous normal woman, what is the probability that they will have a son with hemophilia?
In the context of hemophilia, if a man with hemophilia mates with a homozygous normal woman, what is the probability that they will have a son with hemophilia?
Signup and view all the answers
What is the probability that a son from a man with the normal form of the blood clotting factor and a carrier woman will have hemophilia?
What is the probability that a son from a man with the normal form of the blood clotting factor and a carrier woman will have hemophilia?
Signup and view all the answers
What is the expected phenotype ratio for female offspring when a homozygous dominant female crosses with a red-eyed male?
What is the expected phenotype ratio for female offspring when a homozygous dominant female crosses with a red-eyed male?
Signup and view all the answers
For a man with hemophilia and a carrier woman, what is the probability that their daughters will have hemophilia?
For a man with hemophilia and a carrier woman, what is the probability that their daughters will have hemophilia?
Signup and view all the answers
Study Notes
Genetics Study Guide Questions
- Define genes, alleles, phenotype, genotype, homozygous, heterozygous, dominant allele, and recessive allele.
- Complete dominance means one allele completely masks the effect of another. An example is tall pea plants (dominant) over short pea plants.
- A carrier has one recessive allele and one dominant allele; the dominant allele masks the effect of the recessive allele.
- Incomplete dominance is when the heterozygote phenotype is intermediate between the two homozygous phenotypes. (e.g., pink flowers in four o'clock plants)
- Codominance occurs when both alleles are expressed equally in the heterozygote (e.g., roan coat color in cattle)
- Polygenic traits are determined by multiple genes, such as height or skin color. Continuous traits have a range of phenotypes (e.g., human height) and discontinuous traits have discrete phenotypes (e.g., flower color).
- Multifactorial traits are influenced by both genes and environmental factors. (e.g., depression)
- Sex is determined by chromosomes (XX for female and XY for male). Sex-linked traits are those determined by genes on the sex chromosomes. Males are more susceptible to sex-linked recessive traits because they only have one X chromosome.
- A pedigree chart shows inheritance patterns of traits in a family.
- Punnett squares are used to predict the probability of offspring inheriting specific traits.
Genetics Practice Problems
-
Complete Dominance Crosses: Using the example of tall pea plants (T) being dominant over short pea plants (t), and crossing two heterozygous (Tt) tall pea plants,
- the percentage of homozygous dominant (TT) plants is 25%
- the phenotype for homozygous dominant plants is tall
- the percentage of homozygous recessive (tt) plants is 25%
- the phenotype for homozygous recessive plants is short
- the percentage of heterozygous (Tt) tall plants is 50%
- the phenotypic ratio of tall to short plants is 3:1
- Other problems in the document involve similar concepts in different scenarios (e.g., tongue rolling, earlobe type, widow's peak).
Incomplete Dominance
- In incomplete dominance, the heterozygote phenotype is intermediate between the two homozygous phenotypes. (e.g., pink flowers in four o'clock plants).
- Problems involving incomplete dominance (e.g., hair texture in humans) often require determining genotypes and phenotypes of offspring.
Codominance
- In codominance, both alleles are expressed equally in the heterozygote. (e.g., roan coat color in cattle)
- Problems will involve determining the phenotypes of offspring when given specific parental genotypes.
X-Linked Traits
- Sex-linked traits are determined by genes on the sex chromosomes. Males are more susceptible to X-linked recessive traits because they only have one X chromosome.
- Problems concerning hemophilia, a recessive X-linked trait, often require calculating the probability of offspring inheriting the trait given specific parental genotypes.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge on key genetics concepts such as genes, alleles, and inheritance patterns. This quiz covers definitions, dominance, codominance, and polygenic traits, allowing you to explore the complexity of genetic traits and their expression. Ideal for students seeking to reinforce their understanding of genetics.
