Mendel's Experiments and Punnett Squares
13 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

Which of the following is a characteristic of an autosomal recessive disorder?

  • The trait can skip generations. (correct)
  • The trait appears in every generation.
  • The trait is always caused by a mutation in the Y chromosome.
  • The trait is more common in males than females.

    • Huntington's Disease is an example of a recessive disorder.

    False (B)

    What is the primary function of CRISPR technology in genetic engineering?

    CRISPR technology allows for precise editing of DNA sequences, enabling targeted changes to genes.

    A _ is an individual who carries one copy of a recessive allele but does not display the associated trait.

    <p>carrier</p> Signup and view all the answers

    Match the following terms with their corresponding descriptions:

    <p>Hemophilia = A disorder where blood does not clot properly Cancer = Uncontrolled cell growth due to mutations Pedigrees = Tools used to trace inheritance of traits through generations Benign = Non-cancerous tumor that does not spread Malignant = Cancerous tumor that can spread to other tissues</p> Signup and view all the answers

    What is the expected phenotype ratio of the F2 generation in a monohybrid cross between two heterozygous individuals?

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

    A homozygous individual possesses two identical alleles for a specific trait.

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

    What is the purpose of crossing over during meiosis?

    <p>Crossing over increases genetic variation by exchanging genetic material between homologous chromosomes.</p> Signup and view all the answers

    The process of cell division that produces two genetically identical daughter cells is called ______.

    <p>mitosis</p> Signup and view all the answers

    Match the following genetic terms with their definitions:

    <p>Phenotype = The physical expression of a trait Genotype = The genetic makeup of an individual Homozygous = Having two identical alleles for a trait Heterozygous = Having two different alleles for a trait Recessive allele = An allele that is only expressed when two copies are present</p> Signup and view all the answers

    Which of the following best describes the role of meiosis in sexual reproduction?

    <p>To generate genetically unique gametes (sperm and egg cells) (B)</p> Signup and view all the answers

    Incomplete dominance occurs when the heterozygous phenotype is a blend of both parental phenotypes.

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

    Explain the difference between mitosis and meiosis in terms of the number of daughter cells produced and their genetic composition.

    <p>Mitosis produces two genetically identical daughter cells with the same number of chromosomes as the parent cell. Meiosis produces four genetically unique daughter cells with half the number of chromosomes as the parent cell.</p> Signup and view all the answers

    Flashcards

    Mendel's F2 Generation

    75% tall plants and 25% short plants from a cross.

    Dominant Allele

    An allele that masks the effect of a recessive allele.

    Homozygous

    An organism with two identical alleles (e.g., AA or aa).

    Heterozygous

    An organism with one dominant and one recessive allele (e.g., Aa).

    Signup and view all the flashcards

    Phenotype

    The observable physical traits of an organism.

    Signup and view all the flashcards

    Meiosis

    A type of cell division that produces four genetically unique gametes.

    Signup and view all the flashcards

    Crossing Over

    The exchange of genetic material between homologous chromosomes during meiosis.

    Signup and view all the flashcards

    Sickle Cell Anemia

    A genetic disorder causing abnormally shaped red blood cells (recessive trait).

    Signup and view all the flashcards

    Hemophilia

    A blood disorder where blood does not clot properly, often inherited as a sex-linked trait.

    Signup and view all the flashcards

    Huntington's Disease

    A dominant genetic disorder that leads to nerve degeneration and symptoms typically appear in middle age.

    Signup and view all the flashcards

    Autosomal Recessive Trait

    A trait that can skip generations and requires two recessive alleles to be expressed.

    Signup and view all the flashcards

    CRISPR

    A gene-editing technology that allows precise changes to DNA.

    Signup and view all the flashcards

    Tumors

    Abnormal growths in tissue; can be benign (non-cancerous) or malignant (cancerous and spreads).

    Signup and view all the flashcards

    Study Notes

    Mendel's Experiments

    • Mendel studied trait inheritance in pea plants.
    • F1 generation: All plants displayed the dominant trait (e.g., tall).
    • F2 generation demonstrated a 3:1 ratio of dominant to recessive traits (e.g., 75% tall, 25% short).
    • The tall allele (T) is dominant over the short allele (t).

    Punnett Squares & Probability

    • Punnett squares predict genotype and phenotype ratios.
    • Dominant allele (A) masks the recessive allele (a).
    • Recessive alleles are expressed when two copies are present (aa).
    • Homozygous: Two identical alleles (AA or aa).
    • Heterozygous: One dominant and one recessive allele (Aa).
    • Genotype: Genetic makeup (e.g., Aa, AA, aa).
    • Phenotype: Physical traits (e.g., eye color).
    • Monohybrid cross: Involves one trait (like eye color).
    • Dihybrid cross: Involves two traits (eye color & hair type); F2 ratio is 9:3:3:1.
    • Codominance: Both alleles are fully expressed (e.g., speckled chicken).
    • Incomplete dominance: Heterozygous phenotype is a blend (e.g., pink flowers from red and white).
    • Example: BB (black) x ww (white) = all Bb (gray) rabbits demonstrates incomplete dominance.

    Meiosis vs. Mitosis

    Mitosis

    • Purpose: Growth, repair, asexual reproduction.
    • Results in two identical daughter cells.
    • Maintains the chromosome number (diploid).
    • One cell division.

    Meiosis

    • Purpose: Sexual reproduction, genetic variation.
    • Results in four genetically unique gametes (haploid).
    • Two cell divisions.
    • Crossing over in Prophase I increases genetic variation.
    • Independent assortment ensures unique combinations.
    • Chromosome number reduces from 46 (diploid) to 23 (haploid).

    Genetics Terminology

    • Phenotype: Observable traits (e.g., eye color).
    • Genotype: Genetic composition (e.g., BB, Bb, bb).
    • Homozygous: Identical alleles (BB or bb).
    • Heterozygous: Different alleles (Bb).
    • Sex-linked traits: Carried on X and Y chromosomes.
    • Mutation: Permanent DNA changes (harmful, neutral, or beneficial).

    Genetic Disorders & Pedigrees

    • Sickle cell anemia: Abnormally shaped red blood cells (recessive).
    • Cystic fibrosis: Thick mucus in lungs and intestines (recessive).
    • Hemophilia: Blood clotting disorder (sex-linked).
    • Huntington's disease: Dominant disorder causing nerve degeneration.
    • Pedigrees trace trait inheritance through generations.
    • Carriers have one recessive allele but don't show the trait.

    Human Genome & Genetic Engineering

    • Human Genome Project: Mapped all human genes.
    • Selective breeding: Choosing organisms with desired traits.
    • Cloning: Creating genetically identical organisms.
    • Genetic engineering: Altering DNA for medical and agricultural purposes.
    • CRISPR: Gene-editing technology for precise DNA changes.

    Genetic Disorders Review

    • Autosomal dominant: Trait appears in every generation.
    • Autosomal recessive: Trait can skip generations.
    • X-linked traits: More common in males.

    Cancer

    • Cause: Uncontrolled cell growth due to mutations.
    • Tumors: Benign (non-cancerous, non-spreading) or malignant (cancerous, spreading).
    • Treatment: Surgery, chemotherapy, radiation.

    Studying That Suits You

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

    Quiz Team

    Description

    Explore Mendel's foundational experiments on trait inheritance and the use of Punnett squares in genetics. This quiz covers dominant and recessive traits, genotype and phenotype ratios, as well as the concepts of homozygous and heterozygous conditions. Test your understanding of these key principles in genetic science.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser