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What Makes a Plant a Plant . Pgs 74 - 77. Plant Characteristics. Plants come in different shapes and sizes. Plants provide us with many everyday things such as chocolate, cotton for clothes, wood for a roof and paper. Almost all food comes from plants. Plants make their own food.
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What Makes a Plant a Plant Pgs 74 - 77
Plant Characteristics Plants come in different shapes and sizes. Plants provide us with many everyday things such as chocolate, cotton for clothes, wood for a roof and paper. Almost all food comes from plants.
Plants make their own food Most plants are green due to their chloroplasts. Chloroplasts contain chlorophyll that absorbs light energy from the sun. Plants use this energy to make food molecules, like glucose, in a process called photosynthesis.
Plants Have a Cuticle A cuticle is a waxy layer that coats the surface of stems, leaves and other plant parts. The cuticle is an adaptation that prevents plants from drying out.
Plant Cells Have Cell Walls All plant cells are surrounded by a rigid cell wall. It helps support and protect the plant. Cell walls contain complex carbohydrates and proteins that form a hard material. Sometimes a secondary cell wall forms and prevents plant cells from growing any larger.
Plants Reproduce with Spores and Sex Cells A plant’s life cycle has two parts. One is the spore producing stage called a sporophyte. The stage that develops the egg and sperm cells is the gametophyte . Spores can grow into new plants when conditions are right. Sex cells must join together to make a fertilized egg that will grow into a new plant.
The Origin of Plants Plant can chase their ancestry back to green algae. Green algae and plants share many similar characteristics: chlorophyll, cell walls, photosynthesis, and a two part life cycle.
How are plants classified? There are more than 260,000 species of plants living on Earth today. They can be divided into two groups: vascular plants and nonvascular plants. The difference between the two are the ability to form structures that transport water and minerals.
Plants without “Plumbing” Nonvascular plant have no “pipes” to transport water and nutrients. They depend on diffusion and osmosis to move material from one part of the plant to another. Nonvascular plants are very small plants in order to function this way.
Plants with “Plumbing” Vascular plants have tissues that deliver needed materials throughout a plant. These are called vascular tissues and allow plants to be any size. Vascular plants can be divided into two groups: Those that produce seeds and those that do not.
Seedless plants Plants that do not produce seeds are ferns, horsetails, and club mosses.
Plants with seeds Plants that do produce seeds are divided into two categories: gymnosperms and angiosperms. Gymnosperms are nonflowering plants. Angiosperms are flowering plants.