Plant Reproduction Lesson 19.3 PDF

Lesson 19.3: Plant Reproduction B.P: 523-531  P: 523 Reproduction Sexual Asexual Reproduction Reproduction Vegetative Reproduction  Asexual Reproduction witho...

Lesson 19.3: Plant Reproduction B.P: 523-531  P: 523 Reproduction Sexual Asexual Reproduction Reproduction Vegetative Reproduction  Asexual Reproduction without the joining of an egg and Reproduction a sperm New plants grow from Vegetative parts of an existing plant Reproduction that are identical to the original plant. P: 523 Advantages of vegetative reproduction: Faster way to grow than from seed or spore Plants produced are uniform in appearance to their parents Some fruits do not produce seeds, so vegetative P: 523 reproduction is the only way to reproduce  P: 523 Gemmae Liverwort Cup tissue  P: 523 Mitosis: is a process of cell division resulting in two identical cells with the same number of chromosomes (2n). Meiosis : is a process of cell division resulting in four daughter cells with a reduced number of chromosomes (n). Alternation of Generations : P: 524  Flower Structure P: 525 Flowers vary in structure and form from one species to another. In each, the flower has one main function: to ensure that the plant reproduces successfully. Flower P: Organs: 525 Some organs provide support or protection, while others can be involved directly in reproduction. In general, flowers have four organs—sepals, petals, stamens, and one or more pistils. Sepals protect the flower bud and can look like P: 525 small leaves or even resemble the flower’s petals. Petals usually are colorful structures that can both P: attract pollinators and provide them with a landing 525 platform. Sepals and petals, if present, are attached to a flower stalk, called a peduncle.  Most flowers P: 525 have several stamens —the male reproductive organs. A stamen is composed of two parts— the filament and the The filament, or stalk, supports the anther. Inside the P: anther are cells that undergo meiosis and then mitotic cell 525 divisions, forming pollen grains. Two sperm eventually form inside each pollen grain. Each sperm cell will eventually fertilize a different structure inside the female reproductive organ. The female reproductive organ of a flower is the pistil. In the center of a flower is one or more pistils. A pistil usually has three parts: The stigma The style The ovary P: 525 The stigma is the tip of the pistil and is where P: pollination occurs. 525 The style is the part that connects the stigma to the ovary P: that contains one or more ovules. A female gametophyte 525 develops in each ovule, and an egg forms inside each female gametophyte  Flower Adaptations P: 526 Structural Differences: Complete A flower with all flower parts Flowers InComplete A flower missing one or more of Flowers its organs.  P: 526 Complete InComplete Flowers Flowers Structural P: Differences: 526 Perfect A flower with both stamens and Flowers pistils Imperfect A flower has either functional Flowers stamens or pistils not both  P: 526 The number of flower organs distinguishes P: 526 eudicots from monocots. When the petal number and other Eudicots organs for a flower is a multiple of four or five Monocots Flower organs in multiples of three. Pollination mechanisms: Different anthophyta species have flowers of distinctive sizes, shapes, colors, and petal arrangements. Many of these adaptations relate to pollination. P: 526 Pollination mechanisms: P: 526 Self Flowers can pollinate themselves or Pollination another flower on the same plant Flowers receive pollen from Cross another plant. Some flowers must Pollination be cross-pollinated, often by animals. Pollination mechanisms: Animal P: 527 pollinated flowers are brightly colored, have strong scents, or produce a sweet liquid called nectar. Pollination mechanisms: P: 527 Wind Flowers that lack showy or pollinated fragrant floral parts flowers - Produce huge amounts of lightweight pollen. - Stamens are hanged below the petals, exposing them to the wind. - Stigma is large: Ensures that a pollen grain might land on it.  Flowering Plants P: 528 - Division _Anthophyta _ largest and most diverse group of plants. - Provide much of food eaten by humans. - Known as _ Angiosperms _ produce flowers and develop seeds (part of the fruit). Seed and fruit development video video P: 528  P: 528 Seed and fruit development P: 528 Endosperm: Tissue that develops from the double fertilization and provides nourishment for the embryo. Rapid cell divisions without cell wall formation _as the endosperm matures, cell walls form _ ➔ Monocots: Endosperm makes most of the seed’s mass. ➔ Eudicots: The cotyledons absorb most of the endosperm tissue and provide nourishment for the embryo. The liquid inside a fresh coconut is liquid endosperm—cells without cell walls. Seed and fruit development P: 528 Seed coat: A protective tissue that forms as the endosperm matures and the outside layers of the ovule harden. Seed and fruit development P: 528 Thin, outer covering that loosens as seeds are cooked. Seed and fruit development P: 528 Fruits: ➔ Form primarily from the ovary wall. ➔ In some cases, fruits consist of the ovary wall and other flower organs.  P: 529 Seed dispersal Fruits protect and help in seed dispersal. Seed dispersal eliminates the competition between offspring and parents for resources. P: 529 Seed dispersal Other ways of Seed Dispersal: wind or water P: 529 Seed germination When the embryo starts to grow P: 530 Seed germination Factors that affect germination: a. Water b. Oxygen c. Temperature P: 530 Steps of germination: Begins when a seed absorbs water, either as a liquid or gas. The seed swells; this can break the seed coat. Water also transports materials to the growing regions of the seed. P: 530  Within the seed, digestive enzymes help start the breakdown of stored food. Used for growth P: of the plant 530 The first part of the embryo to appear outside the seed is a structure called the radicle that starts absorbing water and nutrients from its environment. Will develop into plant roots P: 530 The hypocotyl is the region of the stem nearest the seed and, in many plants, it is the first part of the seedling to appear above the soil. P: 530 In some eudicots, as the hypocotyl grows, it pulls the cotyledons and the P: embryonic leaves out of the soil. 530 Photosynthesis begins as soon as the seedling’s cells that contain chloroplasts are above ground and exposed to light. In monocots, seedling growth is slightly different because the cotyledon usually stays in the ground when the stem emerges from the soil. P: 530 Video Some seeds can survive Seeds Other seeds can harsh environmental germinate soon germinate after conditions, such as after dispersal long periods. drought and cold. Maple Ginkgo Seeds biloba P: 530 Most seeds produced at the end of a growing season enter dormancy , a period of little or no growth. Dormancy is an adaptation that increases the survival rate of seeds exposed to harsh conditions. The length of dormancy varies from species to species. P: Ginkgo biloba Cucurbita 531