360 likes | 906 Views
Seed Plants. Chapter 22.4 - 22.5. Chapter 22 Vocabulary – Part B. 22.4 Gymnosperm Cone Pollen grain Pollination Seed Embryo Seed Coat. 22.5 Angiosperm Fruit Monocot Dicot Cotyledon Annual Biennial Perennial. Crash Course Biology. Vascular Plants
E N D
Seed Plants Chapter 22.4 - 22.5
Chapter 22 Vocabulary – Part B • 22.4 • Gymnosperm • Cone • Pollen grain • Pollination • Seed • Embryo • Seed Coat • 22.5 • Angiosperm • Fruit • Monocot • Dicot • Cotyledon • Annual • Biennial • Perennial
Crash Course Biology • Vascular Plants • https://www.youtube.com/watch?v=h9oDTMXM7M8&index=38&list=PL3EED4C1D684D3ADF
Evolution of Land Plants REMEMBER: • Plants evolved from a green algal ancestor. • The earliest land plants were nonvascular, spore producers (bryophytes). • Ferns were the 1st vascular, spore producing plants. • Gymnosperms & angiosperms were the 1st vascular, seed plants.
Characteristics of Seed Plants • Multicellular • Autotrophic • Alternation of Generations • Reproduce by Seeds • Vascular tissue for transport
Seed Plants • Seed plants are the most dominant groups of photosynthetic organisms on land. • Seed plants are divided into 2 groups: • 1. Gymnosperms – bear seeds directly on the surface of cones. • Means “naked seed.” • 2. Angiosperms – bear seeds within a layer of tissue that protects the seed. • Means “enclosed seed.”
Reproduction Free from Water • Seed plants do NOT require water for fertilization of gametes. • Seed plants have a life cycle that alternates between a gametophyte stage and a sporophyte stage. • Adaptations that allow seed plants to reproduce without water include flowers, cones, pollination, seeds.
Reproduction – Cones & Flowers • The gametophytes of seed plants grow and mature within the sporophyte structures • The sporophyte structuresare: • Cones– the seed-bearing structures of gymnosperms. • Flowers– the seed-bearing structures of angiosperms.
Reproduction - Pollen • The entire male gametophyte is contained in a tiny structure called a pollen grain. • Pollen grain is carried to the female structure by wind, insects, or small animals • Transfer of pollen from male reproductive structure to the female reproductive structure is called pollination.
Reproduction - Seeds • The seed is an embryo of a plant that is encased in a protective covering and surrounded by a food supply. • Seeds have a stored food supply that provides nutrients to the developing embryo. • The seed coatsurrounds and protects the embryo and keeps the contents of the seed from drying out.
Structure of a Seed Seed Coat Seed Embryo Wing Stored Food Supply
Exit Slip 22.4 • 1. List 4 characteristics of seed plants. • 2. What are the 2 sporophyte structures in seeded plants? • 3. What are the parts of a seed?
22.4 Vocabulary • Gymnosperm • Cone • Pollen grain • Pollination • Seed • Embryo • Seed Coat
Groups of Gymnosperms • There are 4 groups of gymnosperms: • 1. Gnetophytes • 2. Cycads • 3. Ginkgoes • 4. Conifers
Gnetophytes • Small group, consisting of approximately 68 species. • More similar to flowering plants.
Cycads • Palm-like plants that reproduce with large cones. • Most numerous when dinosaurs roamed the Earth. • Grow naturally in tropical and subtropical climates.
Ginkgoes • Only one species living today, Ginkgo biloba. • Fossil ancestors were similar to the species living today. • Often planted in US cities because of their resistance to air pollution.
Conifers • Most common type of gymnosperm. • Have long, thin leaves with a waxy coating to help reduce water loss. • Most conifers are evergreen, retaining their leaves year-round.
Conifers Male Cones Female Cones
22.5 Vocabulary • Angiosperm • Fruit • Monocot • Dicot • Cotyledon • Annual • Biennial • Perennial
Angiosperms • Develop unique reproductive organs known as flowers. • Flowers are an evolutionary advantage because they attract animals, which then transport pollen from flower to flower.
Flowers & Fruits • Flowers contain ovaries, which surround and protect the seeds. • After pollination the ovary will develop into a fruit. • A fruit is a wall of tissue that surrounds a seed. • Protects • Aids in seed dispersal
Angiosperm Diversity • Angiosperms are categorized in multiple ways and can belong to more than one group: • Monocot vs. Dicot • Based on the number of seed leaves. • Woody vs. Herbaceous • Based on stem characteristics. • Annual, Biennial, or Perennial • Based on plant life span.
Monocot vs. Dicot • Monocots and Dicots are named for the number of seed leavesor cotyledons. • A cotyledon is the first leaf or the first pair of leaves produced by the embryo of a seed plant. • Monocots– have one seed leaf. • Dicots – have two seed leaves.
Woody vs. Herbaceous Woody Herbaceous Stems are smooth and non-woody. Includes dandelions, sunflowers, etc. • Produce wood as they grow. • Have a thick cell wall for support. • Includes trees, shrubs, and vines.
Plant Life Spans • Annuals • Complete life cycle in 1 year. • Biennials • Complete life cycle in 2 years. • Year 1: • Germinate • Grow short stems, roots, and sometimes leaves • Year 2: • Grow new stems and roots • Produce flowers and seeds • Die • Perennials • Live for more than 2 years.
Exit Slip 22.5 • 1) What are the 4 groups of gymnosperms? • 2) What is the most common type of gymnosperm? • 3) In what 3 ways are angiosperms categorized? • 4) How can you tell if a plant is a monocot or dicot? • 5) What type of flowering plant completes their life cycle in 2 years?