Plants Kingdom: Plantae Sporophytes are diploid and gametophytes are haploid. Review Photosynthesis and Cellular Respiration Plant provide the base for food chains on land. They also provide shade, shelter and oxygen for animals.

Plant Life Cycle Plant life cycle has 2 alternating phases, a diploid (2N) phase and a haploid (N) phase. This is known as alternation of generations. Mitosis and meiosis alternate to produce the 2 types of reproductive cells which are the spores and gametes. Diploid (2N) phase is known as the sporophyte or spore producing plant. Haploid (N) phase is known as the gametophyte or gamete producing plant.

Plant Life Cycle Plant spores are haploid (N) reproductive cells formed in the sporophyte plant by meiosis that can grow into new individuals is the gametophyte. Gamete is a reproductive cell that is produced by mitosis and fuses during fertilization with another gamete to produce a new individual, the diploid sporophyte. The earliest type of plants, mosses and ferns, required water to reproduce. Seed plants have evolve reproductive cycles can be carried out without water. Many plants have forms of vegetative or asexual reproduction. See Figure 22-2

Movement of H 2 O and Nutrients Plants takes up water and mineral through their roots and make food in their leaves. Specialized tissues carry water and nutrients upward from the soil and distribute the products of photosynthesis throughout the plant body. Simpler types of plants carry out these function by diffusion.

Early Plants Early plants evolved structures that acquire, transport, and conserve water. The first plant evolved from an organism much like the multicellular green algae living today. Green algae have cell walls and photosynthetic pigments that are identical to those of plants. Fossils suggest the first true plant depended on water to complete their life cycles. The evolved of plants are more resistant to the drying sun. These plants are capable of conserving water and reproduce without water.

Plant Kingdom Four groups based on 3 features: 1. Water conducting tissues 2. Seeds 3. Flowers 4. Reproductive structures The first plant evolved from a green algae living in fresh water not in the sea as once thought. Flowering plants have 235,000 species. Page 555