Warm-U Describe five things you can remember about fungi: (for example, what do they eat? what kind of cells do they have? where do you find fungi? Etc.)
Plants Holly Springs High School Biology
What are plants? Multicellular Eukaryotes Cell walls made of cellulose Autotrophic Carry out photosynthesis
Plant Needs Sunlight Water and minerals Gas Exchange Movement/transport of water and nutrients
Overview of Plant Kingdom Flowering plants Cone-bearing plants Ferns and their relatives Mosses and their relatives Green algae ancestor Flowers; Seeds Enclosed in Fruit Seeds Water-Conducting (Vascular) Tissue Gymnosperms Angiosperms ^-thought to have arisen from multicellular green algae (a protist)
Mosses Club mosses & Spike mosses Ferns & Horsetails Gymnosperms Flowering Plants simple vascular tissue vascular tissue becomes complex and branched Seeds
1. Bryophytes – Mosses 2. Ferns 3. Angiosperms 4. Gymnosperms Moss FOUR MAIN GROUPS OF PLANTS…
1. Bryophytes - Mosses No vascular tissues: water transported by osmosis Reproduction depends on water. HornwortLiverwort Moss FOUR MAIN GROUPS OF PLANTS…
Mosses: non-vascular plants… …are plants without a water transfer system – to get water, they must be close to the source Nonvascular plants like mosses and their relatives have no way to transport water up into the plant – this is why they must stay small and close to water.
How do nonvascular plants reproduce?
Life Cycle of a Moss bio.miami.edu Sexual Reproduction Asexual Reproduction Spores but no seeds
2. Ferns First plants to have vascular tissues This allowed them to grow taller and get away from direct contact with water. Use spores to reproduce. Have roots, leaves, and stems.
Seed Plants Reproduction in either flowers or cones 3. Gymnosperms: (cones) naked seeds 4. Angiosperms: (flowers) protected seeds Both have vascular tissue Sexual Reproduction: Pollination SEEDS – plant embryo is surrounded by a protective covering
3. Gymnosperms Seeds produced on cones Needles – good adaptation…why? Cycad
4. Angiosperms Seeds produced in flowers and are protected Special adaptations: 1) Flowers: a) attract animals which helps them transport seeds b) contain ovaries which surround and protect seeds 2) Fruit: protects seeds and is a bribe to animals to eat and spread the seeds elsewhere
4. Angiosperms * Cool Fact: Angiosperms consist of 235,000 species; 90% of the Plant Kingdom
Plant Features & Vocabulary Vascular tissue Xylem and phloem Roots Stems leaves
What is vascular tissue? Tissue that transports water and nutrients throughout the plant. Plant “veins” are a gathering of vascular tissue consisting of: -XYLEM – carries water from roots upward to rest of the plant. -PHLOEM – transports nutrients from the leaves to the rest of the plant Can transport up, against gravity
Vascular System
Plant Parts and Function 1) Roots – underground organs that absorb water and minerals, keep plant upright 2) Stems – support & transport structures connecting roots and leaves 3) Leaves – organs where photosynthesis takes place, has pores for gas exchange *All contain vascular tissue!
Root hairs increase surface area to absorb more water. Xylem moves water and nutrients up to the plant. Phloem moves carbohydrates down to the roots sometimes storing them (example: carrot) sparknotes.com
1) Roots a)Taproots –help plant reach water far below surface. b)Fibrous roots – good at preventing erosion
2) Stems Functions: a)Produce leaves, branches and flowers b)Hold leaves up to sunlight c)Transports substances between roots and leaves
3) Leaves Functions: a)Photosynthesis b)Transpiration: Plant loses water through leaves c)Gas Exchange
Leaf Structures: Gas Exchange Stomata: pore-like openings in the underside of a leaf. Allows CO 2 and O 2 to diffuse in and out. Guard Cells: specialized cells in the epidermis that control the opening and closing of stomata. Each stoma has two guard cells.
Stem Root Leaf Ground tissue Vascular tissue Dermal tissue
Water and nutrient transport in plants 1.Capillary Action – water moves up wall of tube. 2.Transpiration – when water evaporates out/off, pulling force is created to take in water. 3.Root pressure – when soil moisture is high, water diffuses into roots
Plant Reproduction
Reproductive Anatomy Flowering plants have male and female “parts” The Flower Sepals Petals Reproductive parts
Sepal – protects flower before it opens protection
Petals – attract pollinators
Male and Female Parts Male part: STAMEN filament (stalk) anther (tip) Female part: PISTIL stigma (sticky tip) style (stalk) ovary (base)
Flower Structure Filament Anther Stigma Style Ovary Carpel Petal Sepal Ovule Stamen
Pollination Pollen (male gamete) from the anther is released and transported to stigma of other flowers: By insects By mammals By birds By wind Ragweed pollen
Ovule is fertilized grows to become seed protected by seed coat Fruits are mature ovaries protect and disperse seeds. Fruits and Seeds
Seeds = fertilized zygotes (can become a new plant)
Germination Plant emerging from seed (sprouting) Conditions need to be right… What do you think these conditions are? - temperature? - water? - oxygen?
Patterns of Plant Growth All plants follow a pattern of growth that continues throughout the plant’s life. Plant hormones: chemical substances that control a plant’s patterns of growth and development, and the plant’s responses to environmental stimuli. Hormone- producing cells Target cells Movement of hormone
Auxins and Phototropism Auxins: plant hormones that stimulate cell elongation (higher amounts being produced in shaded areas cause plants to bend towards light). Auxins are also responsible for gravitotropism. Tip removed Opaque cap Clear cap Opaque shied over base High concentration of auxin Low concentration of auxin Control
Cytokinins and Gibberellins Cytokinins: plant hormones produced in growing roots and in developing fruits & seeds. – Stimulate cell division and cause dormant seeds to sprout. Gibberellins: plant hormones that cause an increase in the overall size of plants and their structures.
Ethylene Ethylene: In response to auxins, fruit tissues release small amounts of the hormone ethylene. – Ethylene then stimulates fruits to ripen.
Plant Responses (“Taxis” aka “tropisms”) Phototropism: causes a plant to grow toward a light source. Gravitotropism: causes the shoot of a germinating seed to grow out of the soil.
Plant Responses (cont.) Thigmotropism: the response of plants to touch Click ME!