Plant Note Objectives *Know the basic characteristics of all plants. *Be able to describe the basic life cycle for all plants *Know the major characteristics of the division of plants that is the Most abundant and familiar *Know the 2 classes of plants in this division and the major differences Between the two classes *Know the basic flower parts and their functions *Be able to describe the process of pollination and fertilization in the Division Anthophyta and know what is unique about this process for This division *Know the functions of xylem and phloem

General Plant Information -Plant characteristics -all plants are multicellular, autotrophic, eukaryotic, have cell walls -Plants have 3 major parts 1. Roots: major functions are to absorb nutrients, store food, and anchor the plant 2. Stems: major functions are to support the leaves, transport nutrients between the leaves and roots, and to sometimes store food 3. Leaves: major function is to perform photosynthesis

Plant Life Cycle -All plants have 2 major parts to their life cycle -Sporophyte generation and Gametophyte generation -The sporophyte produces haploid spores which grow into haploid gametophytes. -The gametophytes produces haploid gametes that fuse together forming a diploid zygote that grows into diploid sporophyte -in most plants the dominant form of the life cycle is the sporophyte generation—this is the plant that we see and recognize -the gametophyte is microscopic

Divisions of Plants -There are about 10 divisions of plants, but we will be focusing mostly on Only one—it contains about 80% of all plant species -The division Anthophyta--aka the angiosperms contains the Flowering plants—produce seeds in fruit -There are 2 classes of angiosperms -Monocots and Dicots and there are 5 major differences between them 1. Monocots have parallel veined leaves while Dicots have net-veined leaves 2. Monocots have fibrous roots while Dicots have taproots 3. Monocots have their vascular tissue scattered throughout the stem while Dicots have their vascular tissue arranged in a ring in the stem 4. Monocots have flower parts in multiples of 3 and Dicots have flower parts in multiples of 4 or 5

5. Monocots have one cotyledon or seed part and Dicots have 2 cotyledons **Vascular tissue carries substances to different parts of the plant -there are 2 major types of vascular tissue in plants 1. Xylem carries water and minerals throughout the plant 2. Phloem carries food or sugar throughout the plant

Anthophytes produce flowers and seeds enclosed in fruit -There are 4 major whorls or circles of flower parts—we will look at them From the outside working toward the center of the flower 1.Sepals: enclose and protect the flower before it opens -are usually green in color and look like leaves, but are sometimes Brightly colored 2.Petals: are usually brightly colored to attract pollinators 3.Stamens: make up the male reproductive parts of the flower -Anther produces the pollen (which is the male gametophyte and produces the male gametes (sperm)) -Filament supports the stamen 4.Pistil: makes up the female reproductive part of the flower -Stigma is the top part and is the site of pollination -Style -Ovary is the base of the pistil and produces the female gametophyte (female gametes (eggs) made here)

Double Fertilization—Unique to Anthophytes -Pollination is the transfer of pollen from the anther to the stigma -Fertilization is the fusion of the egg and sperm -pollen grain lands on the stigma -pollen grain contains one tube nucleus and 2 sperm nuclei -tube nucleus creates a pollen tube down the style for the sperm to Reach the ovule inside the ovary -the ovule contains 8 nuclei -3 nuclei at the far end of the ovule—these die off -3 nuclei at the end near the opening of the ovule -the center nucleus is the egg -2 nuclei in the center of the ovule -one sperm fertilizes the egg creating the zygote that develops into a Plant embryo -one sperm fertilizes the polar nuclei to create the triploid Endosperm -the endosperm is a stored source of food for the plant embryo