3.3 Animal Reproduction gonad testes ovary metamorphosis

Animal Reproductive Organs 3.3 Animal Reproduction Animal Reproductive Organs Gonads 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.

Internal Fertilization 3.3 Animal Reproduction Internal Fertilization Internal 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. Examples Earthworms, spiders, insects, reptiles, birds, and mammals

External Fertilization 3.3 Animal Reproduction External Fertilization External 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. Examples Jellyfishes, clams, sea urchins, sea stars, many fish species, and amphibians

External Embryo Development 3.3 Animal Reproduction External Embryo Development Animals whose embryos develop outside the mother are usually protected inside an egg.

3.3 Animal Reproduction Metamorphosis A developmental process in which the form of the body changes as an animal grows from egg to adult

3.3 Animal Reproduction Internal Development The 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.

3.3 Animal Reproduction Gestation Gestation 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.

Where are sperm formed in male animals? A eggs B ovaries C testis 3.3 Animal Reproduction A B C D Where are sperm formed in male animals? A eggs B ovaries C testis D glands Lesson 3 Review

How is the embryo in an egg nourished? A the outer covering 3.3 Animal Reproduction A B C D How is the embryo in an egg nourished? A the outer covering B an organ transfers nourishment from the mother C fluid produced in glands near the testes D the yolk Lesson 3 Review

D internal development 3.3 Animal Reproduction A B C D What is the developmental process in which the form of the body changes as an animal grows from egg to adult? A metamorphosis B gestation C fertilization D internal development Lesson 3 Review

End of Lesson 3

3.4 Asexual Reproduction asexual reproduction fission budding regeneration cloning

3.4 Asexual Reproduction Asexual Reproduction The production of offspring by one parent without a sperm and an egg joining Results in offspring that are genetically identical to the parent organism

Advantages of Asexual Reproduction No time or energy expended finding a mate. Less time to produce offspring Parent and offspring are genetically identical—equally well-adapted to the same environmental conditions.

Disadvantages of Asexual Reproduction Lack of genetic variation. Harmful mutations in the cells of an organism will be passed to offspring

Types of Asexual Reproduction Prokaryotes reproduce asexually by cell division that does not involve mitosis. Eukaryotes reproduce asexually by mitosis and cell division.

3.4 Asexual Reproduction Fission Bacteria reproduce by a process called fission which produces two genetically identical cells very rapidly.

3.4 Asexual Reproduction Mitotic Cell Division Some single-celled eukaryotes reproduce by mitotic cell division—mitosis followed by cell division. Produces two identical cells. Each cell is an organism.

3.4 Asexual Reproduction Budding Asexual reproduction in which a new organism forms on the parent organism The new organism—a bud—forms by mitosis and cell division, and eventually separates from the parent Example Some single-cell (yeast) and multicellular eukaryotes (hydra)

3.4 Asexual Reproduction Plant Cuttings If 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. Examples Strawberry plants and kalanchoe plants

3.4 Asexual Reproduction Animal Regeneration Some 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.

3.4 Asexual Reproduction What 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.

3.4 Asexual Reproduction Plant Cloning

3.4 Asexual Reproduction Animal Cloning The first animal to be successfully cloned was a sheep named Dolly, in 1996

3.4 Asexual Reproduction A B C D What type of asexual reproduction involves reproduction by cell division only? A fission B budding C regeneration D cloning Lesson 4 Review

A mitotic cell division B cloning C regeneration D budding 3.4 Asexual Reproduction A B C D What type of asexual reproduction involves a new organism forming on the parent organism? A mitotic cell division B cloning C regeneration D budding Lesson 4 Review

3.4 Asexual Reproduction A B C D What type of asexual reproduction involves producing a new animal from pieces of an animal’s body? A plant cuttings B cloning C regeneration D budding Lesson 4 Review

End of Lesson 4

Chapter Resources Menu Chapter Assessment California Standards Practice Concepts in Motion Image Bank Science Online Virtual Lab BrainPOP Click on a hyperlink to view the corresponding feature.

A B C D What is the name for the process of a sperm cell and an egg cell fusing together? A sexual reproduction B fertilization C meiosis D pollination Chapter Assessment 1

What is one advantage of sexual reproduction? B C D What is one advantage of sexual reproduction? A produces many offspring B offspring are genetically identical C offspring have more genetic variation D can produce offspring quickly Chapter Assessment 2

Where are pollen grains formed? A anther B ovule C testes D pollen tube Chapter Assessment 3

What are animal reproductive organs called? A zygotes B gonads C embryos D buds Chapter Assessment 4

What is not an advantage of asexual reproduction? B C D What is not an advantage of asexual reproduction? A organism does not have to spend time and energy finding a mate B can produce a number of offspring faster than with sexual reproduction C offspring have more genetic variation D parent and offspring are equally well adapted to the same environmental conditions Chapter Assessment 5

What type of organism can reproduce asexually by regeneration? SCI 2.a A B C D What type of organism can reproduce asexually by regeneration? A human B sea star C bacterium D yeast CA Standards Practice 1

What flower structure becomes fruit surrounding the seed? A stamen SCI 2.a A B C D What flower structure becomes fruit surrounding the seed? A stamen B pollen tube C ovary D pistel CA Standards Practice 2

A alternation of generations B asexual reproduction C metamorphosis SCI 2.a A B C D What term describes the development of a ladybug larva to an adult ladybug? A alternation of generations B asexual reproduction C metamorphosis D mitotic cell division CA Standards Practice 3

What type of seed plant does not produce flowers? A seedless plants SCI 2.a A B C D What type of seed plant does not produce flowers? A seedless plants B gymnosperms C angiosperms D strawberry plants CA Standards Practice 4

SCI 2.a A B C D How many times does division of the nucleus and cytokinesis happen in meiosis? A one B two C three D four CA Standards Practice 5

Meiosis and Fertilization Concepts in Motion 1

Concepts in Motion 2

Image Bank

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