Biology Chapter 20: Plants Flashcards
Multicellular eukaryotes, most of which produce their own food through photosynthesis
Plants
Land plants evolved from ____________
Green Algae
What evidence supports that land plants have evolved from ancient green algae?
-Multicellular eukaryotes
-Photosynthetic (usually)
-Contain cellulose in cell walls
-Same types of chlorophyll
-Use starch as a storage product
What plant characteristics likely originated in the ancient green algae (class Charophyceae)?
-Multicellular body led to specialization of cells and tissues
-Cell division that produces cells with small channels in their walls to allow cells to communicate with each other chemically
-Reproduction (sperm fertilizing egg cell)
How did natural selection likely play into water plants adapting to land?
As conditions became drier, natural selection began to favor plants that could withstand longer dry periods. Eventually, plants adapted to live fully on land.
True plants have __________
Multicellular embryos that remain attached to the female parent as they develop
What adaptations did plants have to make to survive on land?
Retaining moisture- Cuticle, stomata
Transporting Resources- Vascular system
Growing Upright- Lignin
Reproducing on Land- Pollen grain and seeds
Waxy, waterproof layer on plants that helps hold in moisture
Cuticle
Tiny holes in the cuticle of plants that close to prevent water loss or open to allow air to move in and out
Stomata
A collection of specialized tissues that allow for the transport of resources throughout a plant
Vascular System
What advantages do plants with vascular systems have?
Plants with vascular systems are able to grow taller and get more sunlight and carbon dioxide, while still being able to get water and nutrients from the soil below.
A material that hardens the cell walls of vascular tissues in plants to support the weight and structure of plants
Lignin
Adaptations that allow plants to reproduce without water
Pollen grain and seeds
A two-celled structure that contains a cell that will divide to form sperm; can be carried by wind or animals
Pollen grain
A storage device for a plant embryo
Seed
In all plants, eggs are fertilized ______ the tissue of the parent plant
Within
An interaction between two species in which both species benefit
Mutualsim
Competitive (natural selection) or mutualistic relationships between the adaptations of plants and animals
Plant-Herbivore Interactions
What are the characteristics of seedless nonvascular plants?
-Grow close to the ground or on surfaces where they can directly absorb water
-Rely on free-standing water for reproduction (sperm swims to and fertilizes eggs)
Examples of seedless nonvascular plants:
Mosses, Liverworts, Hornworts
Characteristics of Liverworts:
Seedless Nonvascular
Phyla Hepatophyta
Grow in damp environments
Grow close to the ground to retain moisture and nutrients
Two Types: Thallose: Small-umbrella like structures that reproduce egg-sperm and rely on water for fertilization
Leafy: Reproduce with spores
Characteristics of Hornworts:
Seedless Nonvascular
Phyla Anthocerophyta
Found in tropical forests and along streams around the world
Grow low to the ground
Main body has a flat, lobed appearance with little green horns rising above the flat plant body
Reproduce with spores
Characteristics of Mosses:
Seedless Nonvascular
Phyla Bryophyta
Some have cuticles or stomata
Grow in clumps, green, grow low to the ground
Anchor themselves to surfaces with rhizoids
Tolerant of harsh weather conditions and bad soil
Reproduce with free standing water: sperm swim to and fertilize eggs
A type of moss commonly used by humans for use of fuel (burned peat), or in diapers and bandages, and has antibacterial properties
Sphagnum
Characteristics of Seedless Vascular Plants:
-Depend on water for reproduction
-Can grow higher than seedless nonvascular plants
Common Seedless Vascular Plants:
Club Mosses
Ferns
Whisk Ferns
Horsetails
Characteristics of Club Mosses:
Not true mosses
Seedless Vascular
Belong to the oldest living group of vascular plants; wiped out when the Carboniferous climate cooled but some smaller species survived
Some common species (Lycopodium) look like tiny pine trees and are sometimes called “ground pines”
Rely on free standing water for reproduction
Can grow taller because of vascular systems
Characteristics of Whisk Ferns:
Seedless Vascular
Grow mostly in the tropics and subtropics
Lack true roots and leaves
Closely related to ferns
Characteristics of Horsetails:
Seedless Vascular
Grow in wetland areas and along rivers and streams
Tan, scalelike leaves that grow in whorls around a tubular system
Cell walls contains a rough compound called silica that colonial settlers used to scrub pots
Were much larger and common during the Carboniferous period
Characteristics of Ferns:
Seedless Vascular
Grow from underground stems called rhizomes
Have large leaves called fronds (newly forming fronds are called fiddleheads which uncurl as they grow)
Some are houseplants, others grow in the tropics and can grow over three stories tall
Characteristics/Advantages of Seed Plants (includes cone-bearing plants and flowering plants)
-Can reproduce without free-standing water
-Seeds nourish and protect plant embryos
-Seeds allow plants to disperse to new places
Flowering plants reproduce through pollination and then fertilization
Cone-bearing plants reproduce with pollen that is is produced by their cones and distributed by the wind
A seed plant whose seeds are not enclosed in a fruit
Gymnosperm
A seed plant that has seeds enclosed in some type of fruit
Angiosperm
The reproductive structure of most gymnosperms
A woody cone:
Hard protective scales
Pollen is in male cones; eggs are in female cones (seeds develop on the scales of female cones)
Characteristics of Cycads
Seed plant
Gymnosperm
Look like palm trees with large cones
Provided food for dinosaurs
Grow in tropical areas
Endangered because of their slow growth and loss of habitat in those areas
Characteristics of Ginkgo
Seed plant
Gymnosperm
Has two-lobed leaves
“Burls”/Cones are the reproductive structures
Darwin called the species Ginkgo Biloba a “living fossil”
May be the oldest living species of seed plants
Grown around the world in gardens and used in urban landscaping
Characteristics of Conifers:
Seed Plant
Gymnosperm
Familiar trees with needlelike leaves (pines, redwoods, spruce, cedar, fir, juniper)
Many conifers are evergreen
Grow old and tall
Reproduce with cones
Characteristics of Flowering Plants:
Seed Plants
Angiosperms
Flower is the reproductive structure (protects gametes and fertilized eggs)
Fruit is the mature ovary
Adaptations of Flowering Plants:
Flowers and Pollination: animals feed from a flower, and get pollen on themselves. When it moves on to another flower, some of the pollen brushes off onto the new flower. This way, flowers don’t need to produce nearly as much pollen as plants that rely on wind pollination.
Fruits and Seed Dispersal: Animals eat and digest fruits. When they pass through an animal, they are deposited in a supply of fecal fertilizer that is helpful during germination
An embryonic leaf inside a seed; “seed leaves”
Cotyledon
Flowering plants whose embryos have one seed leaf
Monocots
Key features in Monocots:
One cotyledon
Parallel veins
Flower parts in multiples of three
Scattered Vascular Tissue
Flowering plants whose embryos have two seed leaves
Dicots
Key features in Dicots:
Two cotyledons
Netlike veins (on leaves)
Flower parts in multiples of four or five
Ringed vascular tissue
A fibrous material made up of dead cells that are part of the vascular system of some plants
Wood
Woody plants that have stiff stems and branches (caused by high concentrations of lignin and cellulose in cell walls) have _______ stems
Woody
Plants that do not produce wood have ______ stems
Herbaceous
Flowerig plants that mature from seeds, produce flowers, and die all in one year
Annual
Flowering plants that take two years to complete their life cycle
Biennials
Any flowering plant that lives for more than two years
Perennial
The study of plants
Botany
The study of how people in different cultures use plants
Ethnobotany
History of plant use
Hunting and gathering; people must become familiar with the resources in their surrounding when they move around frequently
Benefit of farming
More reliable source of food that can support a growing population
How are plants important economic resources?
Traded in world markets every year for billions of dollars
The study of drugs and their effects on the body
Pharmacology; many medicines are derived from plants
Potent plant chemicals that contain nitrogen
Alkaloids; some have anti-cancer properties because they interfere with cell division
