Mendel's Experiments and Inheritance Laws
48 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What type of variation did Mendel primarily work with in his experiments?

  • Phenotypic variation
  • Discontinuous variation (correct)
  • Continuous variation
  • Environmental variation

What was the common misconception about inheritance during Mendel's time?

  • Traits blended together to form an intermediate appearance. (correct)
  • All traits were passed down automatically.
  • Traits were inherited as separate entities.
  • Only dominant traits could be inherited.

In what year did Mendel publish his most notable work?

  • 1866 (correct)
  • 1868
  • 1865
  • 1870

What role did Mendel take on in 1868 that led to him abandoning his scientific pursuits?

<p>He became abbot of the monastery. (B)</p> Signup and view all the answers

Which aspect of Mendel's work went unrecognized during his lifetime?

<p>His scientific contributions were overlooked (B)</p> Signup and view all the answers

What does continuous variation refer to?

<p>The range of small differences in a characteristic (B)</p> Signup and view all the answers

What was the main outcome of Mendel's experiments with discontinuous variation?

<p>Offspring inherited distinct traits from their parents. (D)</p> Signup and view all the answers

When was Mendel’s work rediscovered, leading to its revitalization?

<p>1900 (C)</p> Signup and view all the answers

What did Mendel discover regarding the F1 generation when he crossed plants with white and violet flowers?

<p>100% of the F1 hybrids had violet flowers. (D)</p> Signup and view all the answers

Which statement best describes Mendel’s approach to ensuring a valid understanding of flower color inheritance?

<p>Mendel used plants that bred true for both flower colors. (B)</p> Signup and view all the answers

How did Mendel confirm that the only difference in the plants was flower color?

<p>He ensured the other characteristics were identical. (D)</p> Signup and view all the answers

What was the expected outcome of blending traits that was disproven by Mendel’s findings?

<p>Hybrid plants should have qualities of both parents. (C)</p> Signup and view all the answers

In his experiments, what characteristic did Mendel examine regarding seed texture?

<p>Seeds exhibited a single dominant trait regardless of generation. (C)</p> Signup and view all the answers

What was Mendel’s method for performing his crosses?

<p>He exchanged pollen between plants of different traits. (C)</p> Signup and view all the answers

What role did the large number of F2 plants play in Mendel’s experiments?

<p>They helped Mendel to observe variations in traits. (C)</p> Signup and view all the answers

Why was Mendel’s confirmation of true breeding plants essential to his experiments?

<p>It ensured that the traits studied were consistent and reliable. (A)</p> Signup and view all the answers

What is the primary distinction between phenotypic and genotypic ratios?

<p>Phenotypic ratios are based on visible traits, while genotypic ratios are based on gene combinations. (C)</p> Signup and view all the answers

According to Mendel’s law of dominance, which scenario results in the expression of a dominant trait?

<p>A heterozygote will display the dominant trait while the recessive remains concealed. (D)</p> Signup and view all the answers

In the provided genotype examples, which phenotype corresponds to the genotype 'yy'?

<p>Green (C)</p> Signup and view all the answers

What distinguishes phenotype from genotype in Mendel's experiments?

<p>Phenotype is the observable trait while genotype is the genetic constitution. (C)</p> Signup and view all the answers

What does Mendel mean by 'latent unit factor'?

<p>A hidden recessive allele that is not expressed. (D)</p> Signup and view all the answers

Which genetic scenario will lead to a recessive trait being exhibited in offspring?

<p>One parent is homozygous recessive and the other is heterozygous. (D)</p> Signup and view all the answers

When true-breeding yellow seed plants are crossed with green seed plants, what is the genotype of the F1 offspring?

<p>Yy (D)</p> Signup and view all the answers

Which statement about the alleles in Mendel's pea plants is correct?

<p>The genotype Yy represents a plant that is heterozygous for the trait. (C)</p> Signup and view all the answers

What phenomenon occurs when true-breeding violet-flowered plants are crossed with white-flowered plants?

<p>All offspring will show violet flowers, concealing the white allele. (C)</p> Signup and view all the answers

What can be concluded about homozygous dominant and heterozygous individuals?

<p>They exhibit the same phenotype but have different genotypes. (B)</p> Signup and view all the answers

What does it mean for a plant to be homozygous for a gene?

<p>It has two identical alleles for that gene. (B)</p> Signup and view all the answers

How are dominant alleles transmitted to offspring?

<p>Along with recessive alleles from both parents equally. (B)</p> Signup and view all the answers

Why did the green seed allele appear in some F2 offspring?

<p>The F2 generation included homozygous individuals. (D)</p> Signup and view all the answers

What is the genotype of the F1 plants that result from crossing a true-breeding yellow seed plant (YY) with a true-breeding green seed plant (yy)?

<p>Yy (C)</p> Signup and view all the answers

What does the 'P' generation refer to in Mendel's experiments?

<p>The initial parental generation used for crosses. (A)</p> Signup and view all the answers

In Mendel's experiments, what does the term 'true-breeding' imply?

<p>The plants produce offspring that are genetically identical for that trait. (B)</p> Signup and view all the answers

What is the genotype of the offspring in the F1 generation from the cross of true-breeding wrinkled green seeds (rryy) and round yellow seeds (RRYY)?

<p>RrYy (D)</p> Signup and view all the answers

If a dihybrid cross is performed between RrYY and rrYy, how many unique gametes can be produced by RrYY?

<p>2 (B)</p> Signup and view all the answers

What phenotypic ratio do F2 offspring exhibit when conducting a dihybrid cross?

<p>9:3:3:1 (B)</p> Signup and view all the answers

Which law indicates that each gamete can have only one allele per gene?

<p>Law of Segregation (C)</p> Signup and view all the answers

In a Punnett square for the dihybrid cross, how many total squares are created?

<p>16 (A)</p> Signup and view all the answers

What is the expected occurrence of wrinkled-green seeds in the offspring described from the dihybrid cross?

<p>12.5% (A)</p> Signup and view all the answers

When a gamete from a heterozygous plant receives an 'r' allele, which alleles could it also receive?

<p>Either Y or y (D)</p> Signup and view all the answers

Which of the following processes can demonstrate the basis for the law of independent assortment?

<p>Meiosis I (D)</p> Signup and view all the answers

What is meant by the term 'wild type' in genetics?

<p>The most common phenotype or genotype in a natural population (D)</p> Signup and view all the answers

How many alleles for a given gene can an individual organism have?

<p>Two (D)</p> Signup and view all the answers

In the ABO blood-type system, which alleles are codominant?

<p>IA and IB (C)</p> Signup and view all the answers

What results from an individual carrying the IA and i alleles in terms of blood type?

<p>Type A blood (A)</p> Signup and view all the answers

How does having multiple alleles affect the phenotypes observed in a population?

<p>It increases the number of potential genotypes (A)</p> Signup and view all the answers

Which of the following statements about alleles is true?

<p>Alleles can vary in dominance and expressiveness. (D)</p> Signup and view all the answers

Which of these statements accurately reflects the inheritance of the ABO blood groups?

<p>Six genotypes can be formed from three alleles. (A)</p> Signup and view all the answers

What is a common characteristic of blood type alleles IA, IB, and i in relation to dominance?

<p>IA and IB are both dominant over the i allele. (B)</p> Signup and view all the answers

Flashcards

Mendel's Experiments

Mendel's work demonstrating the faithful transmission of traits from parents to offspring in specific patterns.

Discontinuous Variation

Variation in a trait where each individual displays one of a few easily distinguishable traits (e.g., violet or white flowers).

Continuous Variation

A range of small differences seen in a characteristic like human height among individuals.

Inheritance (in genetics)

The process by which genetic material is passed from parents to offspring, often through gametes.

Signup and view all the flashcards

Mendel's Publication Year

Mendel published his work in 1866.

Signup and view all the flashcards

Rediscovery of Mendel's Work

Mendel's work wasn't recognized until 1900, when scientists rediscovered and re-evaluated it.

Signup and view all the flashcards

Gamete cells

Reproductive cells (e.g., eggs and sperm) that carry genetic material.

Signup and view all the flashcards

Blended Inheritance (incorrect idea)

The incorrect early idea that parental traits blended to produce an intermediate appearance in offspring.

Signup and view all the flashcards

Mendel's Flower Color Cross

Mendel crossed pea plants with contrasting flower colors (white and violet) to study inheritance patterns.

Signup and view all the flashcards

True-breeding plants

Plants that always produce offspring with the same trait when self-pollinated.

Signup and view all the flashcards

F1 generation

The first generation of offspring resulting from a cross between two parent plants.

Signup and view all the flashcards

F2 generation

The second generation of offspring from the cross of two first-generation (F1) offspring.

Signup and view all the flashcards

Trait

A characteristic or feature that varies among individuals.

Signup and view all the flashcards

Flower Color

One of the seven characteristics Mendel studied, with contrasting traits of violet and white.

Signup and view all the flashcards

Contrasting traits

Different forms of a characteristic (e.g., white vs. violet flowers).

Signup and view all the flashcards

Dominant trait

A trait that completely masks the expression of a recessive trait.

Signup and view all the flashcards

Phenotype

The observable characteristics or traits of an organism, such as flower color or seed shape.

Signup and view all the flashcards

Genotype

The genetic makeup of an organism, represented by the specific combination of alleles it possesses.

Signup and view all the flashcards

Homozygous

Having two identical alleles for a particular gene. e.g., YY or yy.

Signup and view all the flashcards

Heterozygous

Having two different alleles for a particular gene. e.g., Yy.

Signup and view all the flashcards

Dominant Allele

An allele that masks or overrides the expression of the recessive allele when present in a heterozygous state.

Signup and view all the flashcards

Recessive Allele

An allele whose expression is masked by a dominant allele when present in a heterozygous state.

Signup and view all the flashcards

True-Breeding

Organisms that always produce offspring with the same phenotype as themselves when self-fertilized or crossed with another true-breeding individual.

Signup and view all the flashcards

Hybrid Offspring

Offspring resulting from the cross of parents with different traits, possessing a combination of alleles from both parents.

Signup and view all the flashcards

Phenotypic Ratio

The proportion of different visible traits in offspring.

Signup and view all the flashcards

Genotypic Ratio

The proportion of different gene combinations in offspring.

Signup and view all the flashcards

Law of Dominance

In a heterozygote, the dominant allele's trait is expressed, masking the recessive allele's trait.

Signup and view all the flashcards

Dihybrid Cross

A breeding experiment where two organisms that differ in two characteristics are crossed, analyzing how each trait is inherited.

Signup and view all the flashcards

Independent Assortment

Genes for different traits are inherited independently of each other, meaning alleles for one trait don't influence the inheritance of alleles for another.

Signup and view all the flashcards

Punnett Square

A diagram used to predict the possible genotypes and phenotypes of offspring from a cross.

Signup and view all the flashcards

Multiple Alleles

When a gene has more than two possible alleles in a population. Each individual still only has two alleles.

Signup and view all the flashcards

Wild Type

The most common phenotype or genotype in a population, often considered the 'normal' form.

Signup and view all the flashcards

Variant

Any phenotype or genotype that differs from the wild type.

Signup and view all the flashcards

Codominance

When both alleles of a gene are expressed equally in the heterozygote.

Signup and view all the flashcards

ABO Blood Group

A blood type system in humans determined by three alleles, resulting in four possible blood types (A, B, AB, O).

Signup and view all the flashcards

Genotype vs. Phenotype

Genotype refers to the genetic makeup of an organism, while phenotype refers to the observable characteristics.

Signup and view all the flashcards

What is the phenotype of an individual with the genotype IA i?

The individual will have blood type A.

Signup and view all the flashcards

What are the possible genotypes for someone with blood type AB?

The only possible genotype is IA IB. This is because both IA and IB alleles are codominant and are both expressed equally.

Signup and view all the flashcards

Study Notes

Mendel's Experiments

  • Johann Gregor Mendel established the foundation of genetics.
  • Mendel used pea plants for his experiments.
  • Pea plants reproduce quickly and have observable traits.
  • Mendel focused on characteristics with two clearly distinct traits (e.g., purple or white flowers).
  • Mendel conducted controlled crosses (hybridization) of plants.
  • Mendel followed the inheritance of traits from parent to offspring.
  • Mendel's work was initially overlooked.
  • Mendel's experiments demonstrated predictable inheritance patterns.

Laws of Inheritance

  • Mendel's work revealed fundamental principles of heredity.
  • Genes, carried on chromosomes, are the basic functional units of heredity.
  • Mendel's postulates form the basis of Mendelian genetics.
  • Genetic traits are transmitted from parents to offspring in patterns.

Extensions of the Laws of Inheritance

  • Not all traits follow simple Mendelian patterns.
  • Incomplete dominance: Heterozygous offspring display traits that are intermediate between those of the homozygous parents.
  • Codominance: Both traits of the parents are observed in the heterozygous offspring.
  • Multiple alleles: More than two alleles exist for a gene.
  • Sex-linked traits: Traits determined by genes on sex chromosomes.
  • Epistasis: One gene affects the expression of another gene.
  • Polygenic inheritance: Multiple genes contribute to a single trait's expression.

Studying That Suits You

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

Quiz Team

Related Documents

Chapter 8: Patterns of Inheritance PDF

Description

Explore the groundbreaking work of Gregor Mendel in the field of genetics. This quiz covers his experiments with pea plants, the laws of inheritance he established, and the extensions of these laws. Test your understanding of Mendelian genetics and the principles that govern heredity.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser