2.2 Asexual and Sexual Reproduction G.O.2: As species reproduce. Characteristics are passed from parents to offspring.

Reproduction Reproduction produces new individuals of a species. Reproduction produces new individuals of a species. The way a species reproduces determines how much variation the new individuals will have. The way a species reproduces determines how much variation the new individuals will have. Reproduction can produce new individuals that are identical to or very different from one another Reproduction can produce new individuals that are identical to or very different from one another Asexual Reproduction – involves one individual, all of the offspring are identical to that parent Asexual Reproduction – involves one individual, all of the offspring are identical to that parent Sexual Reproduction – usually involves two individuals, the offspring will have a mix of characteristics from both parents Sexual Reproduction – usually involves two individuals, the offspring will have a mix of characteristics from both parents

Asexual Reproduction Type of reproduction with only one parent. Each offspring is identical to the parent (how is this different than sexual reproduction?) Type of reproduction with only one parent. Each offspring is identical to the parent (how is this different than sexual reproduction?) Types of asexual reproduction: Types of asexual reproduction: Budding Budding Binary Fission Binary Fission Spore reproduction Spore reproduction Vegetative reproduction Vegetative reproduction

Asexual Reproduction There are 4 ways that organism reproduce asexually: There are 4 ways that organism reproduce asexually: 1) Binary Fission 2) Budding 3) Spore Production 4) Vegetative Reproduction

Asexual Reproduction Binary Fission: Cell splits in two and produces two identical organisms. 5w Binary Fission: Cell splits in two and produces two identical organisms. 5whttp:// 5whttp:// 5w Budding: parent organism produces a smaller version of itself (known as a bud). The bud eventually detaches from the parent and becomes an independent organism which is exactly the same as the parent. Budding: parent organism produces a smaller version of itself (known as a bud). The bud eventually detaches from the parent and becomes an independent organism which is exactly the same as the parent.

Budding sea sponges Budding tube sponge Budding barrel sponge

Asexual reproduction Spore production – Spores are like seeds but are produced by one parent (seeds require two parents). The spore is identical to the parent. Spore production – Spores are like seeds but are produced by one parent (seeds require two parents). The spore is identical to the parent. Mould Spores

Spores forming on lichen Spores forming on a fern Spore forming bacteria

Types of Asexual Reproduction: 4) Vegetative Reproduction – reproduction that does not involve the formation of a seed - Many plants reproduce this way, but there is more than one method of vegetative reproduction - Each method involves taking a cutting of the parent plant, which will eventually grow identical to the parent

Vegetative Reproduction Grafting Runners Pg. 31 Aspen suckers

Sexual Reproduction Reproduction with two individuals. Most plants and animals reproduce sexually. The offspring has a mix of characteristics of both parents. Reproduction with two individuals. Most plants and animals reproduce sexually. The offspring has a mix of characteristics of both parents.

Sexual Reproduction in Animals Sexual reproduction in animals: Sexual reproduction in animals: re=fvsr re=fvsr

Sexual Reproduction in Animals General process of animal reproduction is similar (from fungi to protists to dragonflies to bears; small details vary) General process of animal reproduction is similar (from fungi to protists to dragonflies to bears; small details vary) Involves gametes (sex cells) Involves gametes (sex cells) Male gametes = Sperm Cell Male gametes = Sperm Cell Female gametes = egg Cell (Ova) Female gametes = egg Cell (Ova) Union of the two gametes during mating is called fertilization Union of the two gametes during mating is called fertilization The fertilized cell created is known as the Zygote The fertilized cell created is known as the Zygote The zygote undergoes continuous divisions (cleavage) to create a multicellular life form called the embryo The zygote undergoes continuous divisions (cleavage) to create a multicellular life form called the embryo

Sexual Reproduction in Animals The cell division will take place inside the female (most mammals) or outisde in an egg (most other animals) The cell division will take place inside the female (most mammals) or outisde in an egg (most other animals) Remember: The embryo is not identical to either parent; it will have a mix of characteristics from both parents Remember: The embryo is not identical to either parent; it will have a mix of characteristics from both parents

Sexual Reproduction in Animals Only one of the many sperm cells surrounding the egg will fertilize the egg. Only one of the many sperm cells surrounding the egg will fertilize the egg. InfoBit: Hermaphrodites InfoBit: Hermaphrodites Common garden worms and slugs are hermaphrodites. They can produce both math and female gametes. Common garden worms and slugs are hermaphrodites. They can produce both math and female gametes. Although most slugs and worms usually prefer to mate with other individuals of their species, in times of environmental stress, they can fertilize themselves. Although most slugs and worms usually prefer to mate with other individuals of their species, in times of environmental stress, they can fertilize themselves.

Sexual Reproduction in Plants Sexual reproduction in plants: Sexual reproduction in plants:

Sexual Reproduction in Plants As in animals, sexual reproduction requires the joining of a male and female gametes to create a zygote, and with continued division, an embryo As in animals, sexual reproduction requires the joining of a male and female gametes to create a zygote, and with continued division, an embryo Most plants produce both male and female gametes; some only produce one or the other Most plants produce both male and female gametes; some only produce one or the other Pollen contains the male gametes (found in the stamen) Pollen contains the male gametes (found in the stamen) Ovules contain the female gametes (found in the pistil) Ovules contain the female gametes (found in the pistil)

Sexual Reproduction in Plants You will need to know all of the structures involved in plant reproduction. You will need to know all of the structures involved in plant reproduction. Stamen Stamen Filament Filament Anther Anther Pistil Pistil Stigma Stigma Style Style Ovary Ovary Ovule Ovule Sepal Sepal Petal Petal Receptacle Receptacle Pistil

Sexual Reproduction in Plants Pollination occurs when pollen is transferred from the anther of the stamen to the stigma of the pistil. Pollination occurs when pollen is transferred from the anther of the stamen to the stigma of the pistil. Fertilization occurs when the male and female gametes unite Fertilization occurs when the male and female gametes unite Cross-Pollination occurs when the pollen of one plant is carried to the stigma of another by wind, water, or animals, such as bees or butterflies Cross-Pollination occurs when the pollen of one plant is carried to the stigma of another by wind, water, or animals, such as bees or butterflies Cross-fertilization occurs when a grain of this pollen produces a long tube that eventually grows down the style into the ovary that contains the ovules Cross-fertilization occurs when a grain of this pollen produces a long tube that eventually grows down the style into the ovary that contains the ovules

Asexual Reproduction Sexual Reproduction

Asexual or Sexual Some species have the ability to reproduce both sexually and asexually. Some species have the ability to reproduce both sexually and asexually. In plants, seeds can often be produced sexually and asexually. If the seeds don’t have a contribution from a sperm cell they will be genetically identical to the parent (i.e. _____________, sunflowers, roses) In plants, seeds can often be produced sexually and asexually. If the seeds don’t have a contribution from a sperm cell they will be genetically identical to the parent (i.e. _____________, sunflowers, roses) In animals, aphids, sponges, __________ and moss can alternate between asexual and sexual reproduction In animals, aphids, sponges, __________ and moss can alternate between asexual and sexual reproduction