Genetics: Basic Concepts
70 Questions
1 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 statements accurately describes an X-linked recessive disorder?

  • It predominantly affects males. (correct)
  • It affects males and females equally.
  • It affects more females than males.
  • It has no impact on females.

    • Barr bodies result from the deactivation of one of the X chromosomes in female cells.

    True

    What is the role of a Barr body in female cells?

    To inactivate one of the two X chromosomes.

    In heterozygous female cats, 50% of the cells express the _____ allele, and 50% express the ____ allele, depending on which chromosome is active.

    <p>orange, black</p> Signup and view all the answers

    Match the following terms related to X-linked traits with their definitions:

    <p>CVD = An X-linked recessive disorder Barr body = Inactive X chromosome in females X-linked recessive = Typically affects more males than females Heterozygous female = A female with two different alleles on her X chromosomes</p> Signup and view all the answers

    What is the primary function of DNA?

    <p>Carriage of genetic information</p> Signup and view all the answers

    An individual that is homozygous for a gene has two different alleles for that gene.

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

    What is a Punnett Square used for?

    <p>To predict the outcome of a breeding experiment.</p> Signup and view all the answers

    The observable physical characteristics of an organism are referred to as __________.

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

    Match the following terms with their definitions:

    <p>Gene = A unit of heredity transferred from parent to offspring Allele = Alternative forms of a gene Chromosome = Structure carrying genetic material Genotype = The genetic constitution of an individual</p> Signup and view all the answers

    Which law states that alleles of two or more different genes get sorted into gametes independently?

    <p>Law of Independent Assortment</p> Signup and view all the answers

    Recessive alleles are expressed in the phenotype when dominant alleles are present.

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

    What determines whether an organism is homozygous or heterozygous?

    <p>The alleles for a particular gene.</p> Signup and view all the answers

    What term describes the inheritance pattern where a gene is located on a sex chromosome?

    <p>Sex-linked Inheritance</p> Signup and view all the answers

    Incomplete dominance results in a phenotype that is a blend of two alleles.

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

    What is the significance of crossing over during meiosis?

    <p>It introduces genetic variation in offspring.</p> Signup and view all the answers

    During __________ I, homologous chromosomes separate and move toward opposite poles.

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

    Match each term with its definition.

    <p>Diploid = Cells containing two sets of chromosomes Haploid = Cells containing one set of chromosomes Somatic cells = Body cells excluding gametes Karyotype = Arrangement of an individual's chromosomes</p> Signup and view all the answers

    Which stage of the cell cycle involves the division of the nucleus?

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

    Homologous chromosomes have different genes at the same locations.

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

    What is produced at the end of telophase II in meiosis?

    <p>Four haploid daughter cells</p> Signup and view all the answers

    The genetic material of an organism is made up of __________.

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

    Which of the following best describes trisomy?

    <p>Having three copies of a chromosome</p> Signup and view all the answers

    The human diploid number is 2n = 46.

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

    Which molecules are the building blocks of DNA?

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

    A __________ involves the fusion of a male and female gamete to form a zygote.

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

    Match the stages of meiosis with their correct descriptions.

    <p>Prophase I = Homologous chromosomes pair and exchange genetic material Metaphase I = Homologous chromosomes align at the cell's equator Anaphase II = Sister chromatids separate to opposite poles Telophase I = Formation of two new cells with half the chromosome number</p> Signup and view all the answers

    What is a pedigree used for?

    <p>To document inheritance patterns of traits in a family</p> Signup and view all the answers

    An autosomal dominant disorder can skip generations.

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

    What are the two types of autosomal disorders?

    <p>Autosomal dominant and autosomal recessive</p> Signup and view all the answers

    The flow chart that shows inheritance patterns over generations is called a ______.

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

    Match the following inheritance patterns with their characteristics:

    <p>Autosomal Dominant = Requires only one copy of the allele to be affected Autosomal Recessive = Requires two copies of the allele to be affected X-linked Recessive = Affected males pass the allele to all daughters Incomplete Dominance = Heterozygotes show a blend of both phenotypes</p> Signup and view all the answers

    Which of the following disorders is an example of an X-linked recessive disorder?

    <p>Duchenne muscular dystrophy</p> Signup and view all the answers

    Polygenic inheritance results in traits with distinct categories.

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

    What is the significance of using superscripts in inheritance patterns?

    <p>Superscripts indicate alleles that demonstrate codominance or incomplete dominance.</p> Signup and view all the answers

    Traits located on the X or Y chromosome are referred to as ______ traits.

    <p>sex-linked</p> Signup and view all the answers

    What type of testing looks for abnormalities in enzymes and proteins?

    <p>Biochemical testing</p> Signup and view all the answers

    Sickle cell anemia demonstrates incomplete dominance.

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

    What does crossing over during meiosis do for linked genes?

    <p>It can unlink genes on the same chromosome.</p> Signup and view all the answers

    The trait for red-green color vision deficiency is an example of a(n) ______ disorder.

    <p>X-linked recessive</p> Signup and view all the answers

    What is the F1 generation in a classical genetics cross?

    <p>First generation of offspring</p> Signup and view all the answers

    What is produced as a result of genetic reduction during meiosis?

    <p>Daughter cells with half the number of chromosomes of the parent cell</p> Signup and view all the answers

    Crossing over occurs during prophase II.

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

    Which process produces sperm cells in male animals?

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

    During meiosis II, sister chromatids are separated during __________.

    <p>anaphase II</p> Signup and view all the answers

    Match the genetic conditions with their causes:

    <p>Down Syndrome = Trisomy 21 Turner Syndrome = Monosomy X Cri du Chat Syndrome = Deletion of a chromosome section Charcot-Marie-Tooth disease = Duplication of a chromosome section</p> Signup and view all the answers

    What is one way genetic variation occurs during meiosis?

    <p>Independent assortment</p> Signup and view all the answers

    All gametes produced during meiosis have the same combination of alleles.

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

    What happens during telophase I of meiosis?

    <p>Nuclear membrane forms around each group of chromosomes</p> Signup and view all the answers

    The technique of __________ involves taking a sample of amniotic fluid to test for genetic disorders.

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

    Match reproductive technologies with their procedures:

    <p>In vitro fertilization = Harvesting eggs and joining them with sperm in a lab Artificial insemination = Introducing sperm into the reproductive tract Pre-implantation genetic diagnosis = Testing an embryo for genetic disorders Cloning = Making identical copies of an organism</p> Signup and view all the answers

    What is a common outcome of non-disjunction during meiosis?

    <p>Gametes with too many or too few chromosomes</p> Signup and view all the answers

    The process of artificial insemination is only applicable to human reproductive technologies.

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

    What is genetic recombination?

    <p>The process by which the products of meiosis have different combinations of alleles.</p> Signup and view all the answers

    Gametes formed through meiosis are __________ cells.

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

    Match the process with its description:

    <p>Spermatogenesis = Production of sperm cells Oogenesis = Production of egg cells Crossing over = Exchange of genetic material between homologous chromosomes Selective breeding = Breeding for desirable traits</p> Signup and view all the answers

    What is one application of genetically modified organisms (GMOs) in plants?

    <p>Increasing nutritional value</p> Signup and view all the answers

    Transgenic animals cannot be modified to produce human proteins.

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

    What percentage chance is there for a specific allele to be passed on to a gamete?

    <p>50%</p> Signup and view all the answers

    The dominant allele for yellow pea seeds is represented by the letter ______.

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

    Match the Mendelian laws of inheritance to their descriptions:

    <p>Law of Segregation = Alleles separate during gamete formation Law of Dominance = Dominant allele masks recessive allele Law of Independent Assortment = Genes for different traits assort independently</p> Signup and view all the answers

    What is a common concern related to herbicide-resistant plants?

    <p>Development of super-weeds</p> Signup and view all the answers

    Mendel's experiments showed a consistent phenotypic ratio of 9:3:3:1 in all crosses.

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

    What term describes the physical expression of an organism's genotype?

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

    When two heterozygous plants are crossed, the expected phenotypic ratio for a single trait is ______.

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

    Match the following traits with their dominant characteristics in pea plants:

    <p>Stem length = Tall Pod shape = Inflated Seed color = Yellow Flower color = Purple</p> Signup and view all the answers

    What is a potential drawback of genetic modification in agriculture?

    <p>Public skepticism and concern</p> Signup and view all the answers

    Mendel believed that traits are inherited independently from one another.

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

    What is the relationship between chromosomes and genes according to the Chromosome Theory of Inheritance?

    <p>Genes are carried on chromosomes.</p> Signup and view all the answers

    In Mendelian genetics, a test cross involves crossing an individual with an unknown genotype with one that is ______.

    <p>homozygous recessive</p> Signup and view all the answers

    Study Notes

    Genetics: Basic Concepts

    • Genetics: The scientific study of heredity and variation.
    • Gene: A unit of heredity determining a characteristic.
    • Chromosome: A thread-like structure of nucleic acids and protein carrying genetic information (genes).
    • DNA (Deoxyribonucleic acid): Self-replicating material, the main component of chromosomes, carrying genetic information.
    • Allele: One of two or more alternative forms of a gene arising by mutation.
    • Genotype: The genetic constitution of an individual (two alleles for a gene).
    • Phenotype: Observable traits of an organism (influenced by genotype and dominance).
    • Homozygous: Having two identical alleles.
    • Heterozygous: Having two different alleles.
    • Dominance: One allele masking the expression of another.
    • Recessivity: An allele's expression masked by a dominant allele.
    • Heredity: Passing traits from parents to offspring.
    • Punnett Square: A diagram used to predict outcomes of genetic crosses.

    Mendel's Laws of Inheritance

    • Law of Segregation: Alleles separate during gamete formation.
    • Law of Independent Assortment: Alleles for different genes separate independently.
    • Law of Dominance: One allele can mask another in the phenotype.

    Cell Division and Reproduction

    • Cell Theory: All living things are composed of cells; cells are the smallest unit of life; new cells arise only from pre-existing cells.
    • Cell Cycle: Interphase (growth/activity), Mitosis (nuclear division), and Cytokinesis (cytoplasm division).
    • Somatic cells: Body cells undergoing cell cycles.
    • Chromosomes: Humans have 23 pairs of chromosomes (22 autosomes, 1 sex chromosome pair).
    • Karyotype: An ordered display of chromosomes.
    • Sexual Reproduction: Fusion of male and female gametes (sperm and egg) creating a zygote.
    • Meiosis: Cell division producing haploid gametes (one set of chromosomes).
    • Meiosis I: Separation of homologous chromosomes.
    • Meiosis II: Separation of sister chromatids.
    • Crossing Over: Exchange of genetic material between homologous chromosomes (prophase I).
    • Independent Assortment (Meiosis): Random alignment of homologous chromosomes.
    • Haploid: One set of chromosomes (n).
    • Diploid: Two sets of chromosomes (2n).
    • Genetic Variation: Variations via independent assortment, crossing over.

    Complex Patterns of Inheritance

    • Incomplete Dominance: Intermediate phenotype in heterozygotes.
    • Codominance: Both alleles fully expressed in heterozygotes.
    • Multiple Alleles: More than two alleles for a gene (e.g., blood type).
    • Polygenic Inheritance: Multiple genes influencing a trait (e.g., height, skin color).
    • Linked Genes: Genes on the same chromosome, not always inherited independently.
    • Sex-linked Inheritance: Traits carried on sex chromosomes (X or Y).
    • Barr Bodies: Inactive X chromosomes in females.

    Genetic Testing and Applications

    • Prenatal Genetic Testing (e.g., Amniocentesis, CVS): Detecting genetic disorders in fetuses.
    • Karyotype: Visualizing chromosome structure.
    • Reproductive Strategies: Selective breeding, artificial insemination, embryo transfer, IVF, preimplantation genetic diagnosis (PGD).
    • Cloning: Gene cloning, therapeutic cloning, and reproductive cloning.
    • Transgenic Organisms: Genetically modified organisms (GMOs) for agricultural and medicinal purposes.

    Human Genetic Disorders

    • Errors in Chromosome structure/number: Deletion, duplication, inversion, translocation.
    • Nondisjunction: Homologous chromosomes or sister chromatids fail to separate during meiosis leading to aneuploidy (ex. Trisomy 21, Monosomy X).
    • Pedigree Analysis: Visual representation of inheritance patterns in families.

    Studying That Suits You

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

    Quiz Team

    Description

    Test your understanding of fundamental genetics concepts. This quiz covers key terms such as genes, chromosomes, DNA, and various inheritance patterns. Explore the basics of heredity, genotype, and phenotype through engaging questions.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser