2Chapter Menu Lesson 1: Sexual Reproduction and Meiosis Lesson 2: Plant ReproductionLesson 3: Animal ReproductionLesson 4: Asexual ReproductionClick on a hyperlink to view the corresponding lesson.
33.1 Sexual Reproduction and Meiosis eggspermfertilizationzygotemeiosisdiploidhaploid
4What is sexual reproduction? 3.1 Sexual Reproduction and MeiosisWhat is sexual reproduction?Reproduction in organisms produces new offspring.Sexual reproduction is the production of an offspring that results when the genetic materials from two different cells combine.
5What is sexual reproduction? (cont.) 3.1 Sexual Reproduction and MeiosisWhat is sexual reproduction? (cont.)Half the genetic material in sexual reproduction is contained in:an egg cella sperm cellIn a process called fertilization, the sperm and egg cells fuse together forming a zygote.Meiosis and Fertilization
6Advantages of Sexual Reproduction 3.1 Sexual Reproduction and MeiosisAdvantages of Sexual ReproductionGenetic variationVariety of genetic traits in a population of the same speciesCan help a species survive changes in environmental conditions
7Advantages of Sexual Reproduction (cont.) 3.1 Sexual Reproduction and MeiosisAdvantages of Sexual Reproduction (cont.)Selective breedingMale and female organisms with certain preferred traits are selected to be the parents of offspring with those preferred traitsProduces groups of organisms with similar traitsReduces genetic variation
8Disadvantages of Sexual Reproduction 3.1 Sexual Reproduction and MeiosisDisadvantages of Sexual ReproductionGetting egg and sperm together for fertilization can be difficultTime is needed for organisms to grow and develop before they can reproduce
9Why is meiosis important? 3.1 Sexual Reproduction and MeiosisWhy is meiosis important?Meiosis is cell division that produces sperm or eggs from certain reproductive cells in an organism.Meiosis ensures that a species’ offspring inherit the correct chromosome number.Without meiosis, the chromosome number would double with each generation.
10Maintaining Diploid Cells 3.1 Sexual Reproduction and MeiosisMaintaining Diploid CellsA diploid cell in an organism contains pairs of homologous chromosomes that equal the chromosome number of that organism’s species.A diploid human cell has 23 pairs of homologous chromosomes.Homologous chromosomes are similar, but not identical.
11Creating Haploid Cells 3.1 Sexual Reproduction and MeiosisCreating Haploid CellsA haploid cell contains one chromosome from each homologous pair.
12Creating Haploid Cells (cont.) 3.1 Sexual Reproduction and MeiosisCreating Haploid Cells (cont.)
133.1 Sexual Reproduction and Meiosis Phases of Meiosis IProphase I—Nuclear membrane breaks apart and chromosomes condense.Metaphase I—Sister chromatids line up along the center of the cell. Cytoskeleton fibers attach to sister chromatids.
14Phases of Meiosis I (cont.) 3.1 Sexual Reproduction and MeiosisPhases of Meiosis I (cont.)Anaphase I—Sister chromatids move to opposite ends of the cell.Telophase I—Nuclear membrane forms around each set of sister chromatids and the cytoplasm divides, forming two daughter cells.
15Phases of Meiosis II Prophase II—Nuclear membrane breaks apart. 3.1 Sexual Reproduction and MeiosisPhases of Meiosis IIProphase II—Nuclear membrane breaks apart.Metaphase II—Chromosomes line up along the center of the cell.
16Phases of Meiosis II (cont.) 3.1 Sexual Reproduction and MeiosisPhases of Meiosis II (cont.)Anaphase II—Sister chromatids of each chromosome begin to separate and move to opposite ends of the cells.Telophase II—A nuclear membrane forms around each set of chromatids, and the cytoplasm divides.
17Comparison of Meiosis and Mitosis 3.1 Sexual Reproduction and MeiosisComparison of Meiosis and Mitosis
18What is the new cell that forms from fertilization called? A sperm 3.1 Sexual Reproduction and MeiosisABCDWhat is the new cell that forms from fertilization called?A spermB eggC haploidD zygoteLesson 1 Review
193.1 Sexual Reproduction and Meiosis BCDHow many chromosomes from each homologous pair does a haploid cell contain?A oneB twoC threeD fourLesson 1 Review
20How many daughter cells are produced in meiosis? A one B two C three 3.1 Sexual Reproduction and MeiosisABCDHow many daughter cells are produced in meiosis?A oneB twoC threeD fourLesson 1 Review
23What is alternation of generations? 3.2 Plant ReproductionWhat is alternation of generations?Some organisms, including plants, have two life stages called generations.One generation has primarily diploid cells, the other generation has only haploid cells.Organisms that alternate between diploid and haploid generations have an alternation of generations.
24What is alternation of generations? (cont.) 3.2 Plant ReproductionWhat is alternation of generations? (cont.)
25How do seedless plants reproduce? 3.2 Plant ReproductionHow do seedless plants reproduce?Seedless plants, such as mosses and ferns, grow from haploid spores, not seeds.Haploid spores that grow by mitosis and cell division into haploid plants.Fertilization results in a diploid zygote that grows by mitosis and cell division into the diploid generation.The diploid generation produces haploid spores by meiosis, and the cycle repeats.
26How do seed plants reproduce? 3.2 Plant ReproductionHow do seed plants reproduce?Most of the land plants that cover Earth grew from seeds—called seed plants.There are flowerless seed plants and flowering seed plants.The haploid generation is within diploid tissue.Separate diploid male and diploid female reproductive structures produce haploid sperm and haploid eggs.
27The Role of Pollen Grains 3.2 Plant ReproductionThe Role of Pollen GrainsA pollen grain forms from tissue in a male reproductive structure of a seed plant.Pollination occurs when pollen grains land on a female reproductive structure of a plant of the same species.
28The Role of Ovules and Seeds 3.2 Plant ReproductionThe Role of Ovules and SeedsThe female reproductive structure of a seed plant contains one or more ovules.After fertilization, a seed develops from the ovule.
29Flowerless Seed Plant Reproduction In flowerless seed plants—gymnosperms— the seeds are not surrounded by a fruit.Cones are the male and female reproductive structures of conifers.Male cones produce pollen grains.Female cones produce eggs.Seeds form as part of the female cone.
30Flowering Seed Plant Reproduction Flowering seed plants—angiosperms—include most of the plants you see.Fruits and vegetables come from flowering seed plants.Seed Plants
31Reproduction and the Flower 3.2 Plant ReproductionReproduction and the FlowerA typical flower has male and female reproductive organs surrounded by petals.The stamen is the male reproductive organ.Pollen grains form at the tip of the stamen, in the anther.The filament is a long stalk that supports the anther and connects it to the base of the flower.
32Reproduction and the Flower (cont.) 3.2 Plant ReproductionReproduction and the Flower (cont.)The female reproductive organ of a flower is the pistil.Pollen can land at the tip of the pistil on the stigma, which is at the top of a long tube called the style.At the base of the style is an ovary containing one or more ovules which eventually will contain a haploid egg.
33Reproduction and the Flower (cont.) 3.2 Plant ReproductionReproduction and the Flower (cont.)
35Fruit and Seed Dispersal 3.2 Plant ReproductionFruit and Seed DispersalFruits and seed are important sources of food for people and animals.Fruits and seeds can be dispersed by:Air currentsAnimalsWaterGravityWhat is the life cycle of a simple plant?
363.2 Plant ReproductionABCDIn alternation of generations, the haploid structures of the diploid generation produces daughter cells called what?A zygotesB sporesC pollenD seedsLesson 2 Review
373.2 Plant ReproductionABCDWhat is an immature diploid plant that develops from the zygote of a seed plant called?A embryoB seedC fruitD stigmaLesson 2 Review
38What is another name for a flowering seed plant? A zygote B conifer 3.2 Plant ReproductionABCDWhat is another name for a flowering seed plant?A zygoteB coniferC gymnospermD angiospermLesson 2 Review
41Animal Reproductive Organs 3.3 Animal ReproductionAnimal Reproductive OrgansGonads are specialized organs that produce sperm or eggs.Testes are male gonads that contain a network of coiled tubes in which sperm cells form.Ovaries are female gonads that produce egg cells.
42Internal Fertilization 3.3 Animal ReproductionInternal FertilizationInternal fertilization happens inside the body of an organism.Internal fertilization ensures that an embryo is protected and nourished until it leaves the female’s body.ExamplesEarthworms, spiders, insects, reptiles, birds, and mammals
43External Fertilization 3.3 Animal ReproductionExternal FertilizationExternal fertilization occurs in the environment, outside of an animal’s body.Most animals that reproduce using external fertilization do not care for the eggs or young.ExamplesJellyfishes, clams, sea urchins, sea stars, many fish species, and amphibians
44External Embryo Development 3.3 Animal ReproductionExternal Embryo DevelopmentAnimals whose embryos develop outside the mother are usually protected inside an egg.
453.3 Animal ReproductionMetamorphosisA developmental process in which the form of the body changes as an animal grows from egg to adult
463.3 Animal ReproductionInternal DevelopmentThe embryos of some animals, including most mammals, develop inside the mother.A tissue or organ transfers nourishment from the mother to the embryo.Other embryos—some snakes, insects, and fishes—develop in an egg with a yolk inside the mother.
473.3 Animal ReproductionGestationGestation is the length of time between fertilization and the birth of an animal.Gestation varies by species and usually relates to the size of the animal at birth—smaller animals have shorter gestation.
48Where are sperm formed in male animals? A eggs B ovaries C testis 3.3 Animal ReproductionABCDWhere are sperm formed in male animals?A eggsB ovariesC testisD glandsLesson 3 Review
49How is the embryo in an egg nourished? A the outer covering 3.3 Animal ReproductionABCDHow is the embryo in an egg nourished?A the outer coveringB an organ transfers nourishment from the motherC fluid produced in glands near the testesD the yolkLesson 3 Review
50D internal development 3.3 Animal ReproductionABCDWhat is the developmental process in which the form of the body changes as an animal grows from egg to adult?A metamorphosisB gestationC fertilizationD internal developmentLesson 3 Review
533.4 Asexual ReproductionAsexual ReproductionThe production of offspring by one parent without a sperm and an egg joiningResults in offspring that are genetically identical to the parent organism
54Advantages of Asexual Reproduction No time or energy expended finding a mate.Less time to produce offspringParent and offspring are genetically identical—equally well-adapted to the same environmental conditions.
55Disadvantages of Asexual Reproduction Lack of genetic variation.Harmful mutations in the cells of an organism will be passed to offspring
56Types of Asexual Reproduction Prokaryotes reproduce asexually by cell division that does not involve mitosis.Eukaryotes reproduce asexually by mitosis and cell division.
573.4 Asexual ReproductionFissionBacteria reproduce by a process called fission which produces two genetically identical cells very rapidly.
583.4 Asexual ReproductionMitotic Cell DivisionSome single-celled eukaryotes reproduce by mitotic cell division—mitosis followed by cell division.Produces two identical cells.Each cell is an organism.
593.4 Asexual ReproductionBuddingAsexual reproduction in which a new organism forms on the parent organismThe new organism—a bud—forms by mitosis and cell division, and eventually separates from the parentExampleSome single-cell (yeast) and multicellular eukaryotes (hydra)
603.4 Asexual ReproductionPlant CuttingsIf you cut a green stem from a houseplant and put it in water, roots and leaves can grow, producing a new plant.Some plants propagate themselves asexually.ExamplesStrawberry plants and kalanchoe plants
613.4 Asexual ReproductionAnimal RegenerationSome animals have cells that can change into other cell types.Regeneration is asexual reproduction that produces new animals from pieces of an animal’s body.Regeneration is sometimes used to describe growth that replaces a missing part of an animal.
623.4 Asexual ReproductionWhat is cloning?Cloning refers to a method of asexual reproduction developed by scientists and performed in laboratories.Cloning produces identical individuals from a cell or cells taken from a multicellular organism.
643.4 Asexual ReproductionAnimal CloningThe first animal to be successfully cloned was a sheep named Dolly, in 1996
653.4 Asexual ReproductionABCDWhat type of asexual reproduction involves reproduction by cell division only?A fissionB buddingC regenerationD cloningLesson 4 Review
66A mitotic cell division B cloning C regeneration D budding 3.4 Asexual ReproductionABCDWhat type of asexual reproduction involves a new organism forming on the parent organism?A mitotic cell divisionB cloningC regenerationD buddingLesson 4 Review
673.4 Asexual ReproductionABCDWhat type of asexual reproduction involves producing a new animal from pieces of an animal’s body?A plant cuttingsB cloningC regenerationD buddingLesson 4 Review
69Chapter Resources Menu Chapter AssessmentCalifornia Standards PracticeConcepts in MotionImage BankScience OnlineVirtual LabBrainPOPClick on a hyperlink to view the corresponding feature.
70ABCDWhat is the name for the process of a sperm cell and an egg cell fusing together?A sexual reproductionB fertilizationC meiosisD pollinationChapter Assessment 1
71What is one advantage of sexual reproduction? BCDWhat is one advantage of sexual reproduction?A produces many offspringB offspring are genetically identicalC offspring have more genetic variationD can produce offspring quicklyChapter Assessment 2
72Where are pollen grains formed? A anther B ovule C testes D pollen tubeChapter Assessment 3
73What are animal reproductive organs called? A zygotes B gonads C embryosD budsChapter Assessment 4
74What is not an advantage of asexual reproduction? BCDWhat is not an advantage of asexual reproduction?A organism does not have to spend time and energy finding a mateB can produce a number of offspring faster than with sexual reproductionC offspring have more genetic variationD parent and offspring are equally well adapted to the same environmental conditionsChapter Assessment 5
75What type of organism can reproduce asexually by regeneration? SCI 2.aABCDWhat type of organism can reproduce asexually by regeneration?A humanB sea starC bacteriumD yeastCA Standards Practice 1
76What flower structure becomes fruit surrounding the seed? A stamen SCI 2.aABCDWhat flower structure becomes fruit surrounding the seed?A stamenB pollen tubeC ovaryD pistelCA Standards Practice 2
77A alternation of generations B asexual reproduction C metamorphosis SCI 2.aABCDWhat term describes the development of a ladybug larva to an adult ladybug?A alternation of generationsB asexual reproductionC metamorphosisD mitotic cell divisionCA Standards Practice 3
78What type of seed plant does not produce flowers? A seedless plants SCI 2.aABCDWhat type of seed plant does not produce flowers?A seedless plantsB gymnospermsC angiospermsD strawberry plantsCA Standards Practice 4
79SCI 2.aABCDHow many times does division of the nucleus and cytokinesis happen in meiosis?A oneB twoC threeD fourCA Standards Practice 5