Vascular Plants Bryophytes. Seedless Plants

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1 plant reproduction The Plants Vascular Plants Bryophytes Liverworts, Hornworts, Mosses lack roots and specialized tissues grow in moist, shady areas All have sieve cells and tracheids Seedless Plants Ferns Seed Plants Angiosperms Monocots, Dicots Gymnosperms Cycads, Ginkos, Conifers

2 plant reproduction Seed Plants: Sexual Reproduction Conifers Seed are produced in cones. male cones contain pollen and female cones contain eggs, and house the seeds as they develop. male pollen producing cone female ovulate cone

3 Angiosperms The most prolific and successful group of plants, the flowering plants include not only those with obvious flowers but also hardwood trees like maple and oak, all the fruits, vegetables, nuts, herbs, grains and grasses. There are two main groups: the monocots which include grasses, palms, irises, orchids, cattails, and the dicots which include trees and shrubs (except conifers), herbs and fruits. The flowering plants are able to reproduce asexually and sexually, through the reproductive organ of the flower.

4 Anatomy of a Flower Sexual Reproduction in Angiosperms petals modified leaves that attract pollinators pistil or carpel female part of flower style

5 Angiosperm Life Cycle Amsel, Sheri. Life Cycle Posters. Apple Tree Life Cycle (Flowering Plant). Exploring Nature Educational Resource October 22, <

6 Seed Germination What do seed need to germinate? Water Heat germination Click here for Radish seed germination video

7 Read pages Complete the flower diagram and flower structures chart. Answer: 1. Describe the process of seed germination, note the order that structures develop. Why does this happen? 2. Describe three methods of seed dispersal.

8 Asexual Reproduction in Angiosperms Vegetative Reproduction The leaves, stems and roots of a plant are the vegetative parts. When these are involved in reproduction, the new plants are genetically identical to the parent plant. Natural Vegetative Reproduction Bulbs: short underground stems surrounded by thick fleshy leaves that store food. e.g. tulips, onions, lilies Tubers: enlarged portion of underground stems that store food. They contain buds that sprout new plants e.g. the "eyes" of a potato

9 Runners: (stolons) horizontal stems with buds that grows along the surface of the ground. Where buds contact the soil new roots stems and leaves form a new plant. e.g. strawberries Rhizomes: Thick fleshy food storing stems that grow horizontally under the ground. Enlarged regions called nodes give rise to new shoots and roots. e.g. cattails, irises, ginger

10 Artificial Vegetative Reproduction Farmers and gardeners have developed methods to force vegetative propagation to maintain plants with desirable traits. Cuttings: Stem and leaf cutting placed in moist soil or water, will sprout new roots. This process can be assisted by the use of plant hormones. Remove Callus Callus & Roots Layering: The stem is bent over so part of it is covered with soil. New roots will form and shoots will emerge. This process also occurs naturally. e.g. herbs such as lavender and mint, raspberries, roses

11 Grafting: The stem or bud of one plant is removed and joined permanently with the stem of a closely related plant. The cambium from each section eventually grow together. The result is a plant with the base from one species (stock) and the shoots and branches of another (scion). This is commonly done for commercial production of fruits such as apples, oranges, grapes and seedless varieties. scion stock waterproof tape

12 Advantages of Artificial Propagation Plants from seeds have characteristics of both parent plants. Plants produced by asexual means have the same (desirable) traits as the parent because they are genetically identical. Vegetative propagation by passes the "seedling" stage and is usually a faster means of increasing numbers of plant or fruits. Seedless varieties can ONLY be cultivated this way! Grafting can be used to produce higher yields of fruit or nut crops.

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