Bio Genetics Q&A Flashcards

What does the Claim, Evidence, and Reasoning model entail in a scientific explanation?

It consists of a clear claim followed by evidence that supports the claim, and reasoning that explains how the evidence supports the claim.

What is the purpose of a claim in scientific writing?

A claim is a statement that answers the question posed and should be presented first in an explanation.

What kind of information constitutes evidence in scientific explanations?

Evidence includes factual data that can be qualitative or quantitative and must be sufficient and relevant to support the claim.

In the context of scientific explanations, what should reasoning include?

Reasoning should contain logical steps that connect the evidence back to the claim, often using terms like 'this implies' or 'this supports'.

How would you describe the average leg lengths of a corgi and a cougar based on the provided data?

Corgis have an average leg length of ~23 cm, while cougars have an average leg length of ~72 cm.

What is the conclusion drawn from the anatomical comparison between a corgi and a cougar?

The conclusion is that a cougar would win a 100m dash because it has a longer step length compared to the corgi.

What does the term 'genome' refer to?

The genome refers to the entire set of DNA found in a cell or organism.

What is a mutation?

A mutation is a change in the nucleotide sequence of DNA that can affect the amino acid sequence and function of proteins.

What key event occurs during crossing-over in meiosis?

Crossing-over involves the exchange of DNA segments between non-sister chromatids of homologous chromosomes.

What is meant by 'linkage' in genetics?

Linkage refers to genes that are located close to each other on a chromosome and tend to be inherited together.

What is a test cross used for in genetics?

A test cross is used to determine the genotype of an individual with a dominant phenotype by crossing it with a homozygous recessive individual.

What does X-linked inheritance imply about the patterns of inheritance for traits on the X chromosome?

X-linked inheritance often leads to different phenotypic ratios between male and female offspring due to the presence of only one X chromosome in males.

What results from a dihybrid cross involving two heterozygous parents?

It produces a phenotypic ratio of 9:3:3:1.

Define incomplete dominance as it pertains to allele interactions.

Incomplete dominance occurs when the heterozygote exhibits a phenotype that is distinct from and intermediate between the phenotypes of the two homozygotes.

What is co-dominance in terms of genetic expression?

In co-dominance, both alleles in a heterozygote contribute to the phenotype without blending, leading to both traits being expressed.

How does environmental influence affect phenotypes?

Environmental factors can interact with an organism's genotype to affect observable traits.

What are the primary modes of inheritance discussed in genetics?

The primary modes include autosomal dominant, autosomal recessive, X-linked dominant, and X-linked recessive.

What is a pedigree and its significance in genetic studies?

A pedigree is a diagram that depicts family relationships and the inheritance of traits across generations, helping to identify patterns of inheritance.

How do you determine a possible mode of inheritance using a pedigree?

By analyzing phenotypic ratios, generational patterns, and the relationships between affected and unaffected individuals.

What assumption is often made when interpreting a pedigree regarding sex chromosomes?

It is commonly assumed that males are XY and females are XX, but individuals can have atypical sex chromosome configurations.

What is the implication of having non-distinct phenotypes in pedigree analysis?

The presence of similar phenotypes may complicate the ability to clearly classify individuals as affected or unaffected.

How many possible gametes can be produced from a dihybrid cross of two heterozygous individuals?

A dihybrid cross of two heterozygous individuals can produce four possible gametes.

What is the role of probability in genetics?

Probability is used to predict the likelihood of certain genotypes or phenotypes occurring in offspring based on parental genotypes.

Why is understanding genetic variation important?

Genetic variation is crucial for the adaptability and survival of a population, especially in changing environments.

What is the phenotypic ratio of a monohybrid cross involving two heterozygous parents?

The phenotypic ratio is 3:1.

Define autosomal recessive inheritance.

Autosomal recessive inheritance occurs when an individual inherits two recessive alleles for a trait, resulting in the expression of that trait.

What is the purpose of a test cross?

A test cross is used to determine if an individual with a dominant phenotype is homozygous or heterozygous for the trait.

How is X-linked recessive inheritance typically expressed in phenotypes?

X-linked recessive traits are more commonly expressed in males, who have only one X chromosome.

What phenotypic ratio results from a dihybrid cross involving a homozygous dominant and a homozygous recessive parent?

The ratio is 100% dominant phenotype.

How can environmental factors contribute to phenotypic variation?

Environmental factors can alter the expression of genes, leading to differences in appearance or behavior of an organism within the same genotype.

What is the significance of identifying traits that exhibit incomplete dominance?

Incomplete dominance provides insight into how alleles can blend phenotypically, showing a range of expressions rather than discrete categories.

What is a pedigree's role in understanding inheritance patterns?

A pedigree visually represents the inheritance of traits over generations, aiding in the study of genetic diseases and traits.

How is the phenotypic ratio affected in cases of co-dominance?

In co-dominance, both alleles are fully expressed in the phenotype, leading to distinct traits being observable rather than blended.