Topic 3 - Monohybrid Inheritance And Genetic Diagrams Flashcards
What do family trees show?
The inheritance of different phenotypes over generations in the same family.
What is a monohybrid cross?
A cross that looks at the probability of the offspring of two parents having certain genotypes and phenotypes.
What diagram is used to visualize the combinations of alleles from parents?
Punnett square diagram.
What do uppercase letters represent in genetic notation?
Dominant characteristics.
What do lowercase letters represent in genetic notation?
Recessive characteristics.
In a Punnett square, what is the chance of having an offspring who is homozygous dominant (BB)?
¼ chance.
Fill in the blank: A monohybrid cross looks at the probability of the offspring of two parents having certain _______.
[genotypes and phenotypes]
What is the purpose of a Punnett square?
To predict the genotype and phenotype probabilities of offspring.
What does homozygous dominant mean?
Having two dominant alleles (BB).
True or False: You can choose any letter to represent alleles in genetic notation.
True.
What is the typical choice of letters used for simplicity in genetic notation?
A or B.
What is the significance of family pedigrees in genetics?
They show how a condition (or the allele causing it) is passed down through generations
Pedigrees help visualize inheritance patterns and identify carriers of genetic conditions.
How do we represent males and females in family pedigrees?
Males are represented by squares and females by circles
This visual distinction helps in tracking inheritance patterns.
What do black shapes represent in a family pedigree?
Affected individuals
Black shapes indicate individuals who exhibit the trait or condition being studied.
What do white shapes represent in a family pedigree?
Unaffected individuals
White shapes indicate individuals who do not exhibit the trait or condition.
What does a line through a shape mean in a family pedigree?
The individual is deceased
This notation helps track the lineage and history of the family.
What does a line passing directly between two shapes indicate?
The two individuals are partners
This shows a marital or partnership relationship in the pedigree.
What does a line overhanging a group of individuals signify?
They are siblings
This notation indicates that the individuals share at least one parent.
What is the relationship between Bb (heterozygous recessive) offspring and symptoms?
Symptoms depend on whether the condition is recessive or dominant
This highlights the role of dominant and recessive alleles in expressing traits.
Fill in the blank: Recessive alleles normally ‘skip a _______.’
generation
This phenomenon occurs when carriers do not express the trait but can pass it to their offspring.
True or False: A homozygous recessive offspring can occur if both parents have the allele.
False
If both parents have the allele, homozygous recessive offspring are not possible.
