plant evolution & roots by: adi beal and madi mcdade
TRANSCRIPT
Plant Evolution & Roots
By: Adi Beal and Madi McDade
Importance of Plants
Botany- the study of plants
Plants have a lot of diversity
Steps of Evolution
1st Step: Multicellular
2nd Step: Move onto Land
3rd Step: Vascular System
4th Step: Seeds
5th Step: Flowers & Fruits
1st Step: Multicellular
Aquatic organisms
Get support from water
Before multicellular
Volvox
Colony of individual cells that cooperate
First multicellular plant
Red Algae
Rhodophyta
Volvox Video
https://www.youtube.com/watch?v=He9FSeGRi3A
2nd Step: Move onto Land
Mosses had no adaptations for life away from water
First terrestrial plants
Bryophyta
Need ozone to block out UV rays which damage DNA
More cellulose for structure
Get water through roots
UV Damage Diagram
3rd Step: Vascular System
True roots and stems
Xylem
Phloem
Waxing coating on leaves to conserve water
Obtain CO2 through stomata, which close at night to prevent water loss
Stomata Diagram
4th Step: Seeds
Dispersed by wind, water, and animals
Spore-individual cells that clump and each contain embryo, an endosperm, and seed coat
Gymnosperms
Seeds are not covered by a true fruit
Gymnosperms Activity
http://studyjams.scholastic.com/studyjams/jams/science/plants/gymnosperms.htm
Seed Dispersal Diagram
Seed Video
https://www.youtube.com/watch?v=6loGKPKDqCw
5th Step: Fruits & Flowers
Fruit- plant structure which results from the pollination of a flower and contains a seed
Fruit may protect the seed
Angiosperms- flowering plant that produce seeds enclosed in a fruit
Flowers produce the reproductive part of the plant
Flowers attract pollinators like bees, bats, and butterflies
Angiosperm Activity
http://studyjams.scholastic.com/studyjams/jams/science/plants/angiosperms.htm
Plant Reproduction Diagram
Plant Evolution Video
https://www.youtube.com/watch?v=yL1o49YGhtM
Plant Adaptations
Waxy Cuticle
Stomata
Reproduction
Spores
Seeds
Vascular Tissues
Xylem
Phloem
Why Do Plants Adapt Activity
http://studyjams.scholastic.com/studyjams/jams/science/plants/plant-adaptations.htm
Monocot vs. Dicot Flowers
Monocot
Parts in threes or multiples of threes
Dicot
Parts in fours or fives or multiples of fours and fives
Monocot vs. Dicot Leaves
Monocot
Smooth often narrow shapes with parallel veins
Dicot
Oval or hand-like shapes with neck-like veins
Monocot vs. Dicot Vascular Tissue
Monocot
Vascular bundles scattered through stem
Dicot
Vascular bundles arranged in ring around stem
Monocot vs. Dicot Root Pattern
Monocot
Fibrous root system
Dicot
Taproot system
Monocot vs. Dicot Embryo in Seed
Monocot
Embryo has one cotyledon (seed leaf)
Dicot
Embryo has two cotyledons (seed leaves)
Monocot Examples
Lilies
Tulips
Bananas
Pineapples
Onions
Corn
Rice
Oats
Dicot Examples
Beans
Lettuce
Oak
Maple
Roses
Daises
Monocots vs. Dicot Video
https://www.youtube.com/watch?v=gI2RxzAT-ww
Monocot vs. Dicot Activity
http://www.math4childrenplus.com/monocots-and-dicots/
Tissue Types
1. Vascular tissue
1. Xylem- transports water to plant
2. Phloem- transports food and minerals
2. Apical Meristem- responsible for upward growth in plant and produces cells that will eventually specialize
Meristem
Types of Roots
1. Primary Root- the first root that appears out of a seed
2. Taproot- primary root grows thicker and longer with secondary roots growing off of it
3. Fibrous root- primary root branches off into many small roots
4. Lateral root- extend horizontally from primary root and anchor plant securely in the soil
5. Aerial root- root exposed to air and absorbs moisture
6. Adventitious root- a root that grows above ground or in an odd place
Root Types
Root Structure
1. Root Cap- hard protective layer, prevents breakage as plant pushed through soil, secretes slimy lubrication
2. Root hairs- increase surface area of root so more water and nutrients can be absorbed, main entry point of water
3. Epidermis- waterproof outermost layer, protection
4. Cortex- many layers of parenchyma cells, stores starch for energy
5. Endodermis- innermost cylinder of cortex, waterproof, regulates movement of water and minerals into vascular tissue
Root Structure (cont.)
6. Pericylce- outermost layer of cells of the steel, goes through cell division creating root hairs
7. Root system- constantly provides the stem and leaves with water and dissolved minerals
8. Root tip- where mitosis occurs
9. Permeable membrane-layer of the cell where water and nutrients can pass through
Root Structure Diagram
Root Growth
https://www.youtube.com/watch?v=eDA8rmUP5ZM
Root Activity
http://studyjams.scholastic.com/studyjams/jams/science/plants/roots-stems.htm
Fun Facts!! Roots are the parts of plain that grow down into soil or water, anchoring it
and soaking up all the water and minerals the plant needs to grow.
In some plants such as beetroots, the roots are also a food store.
When a seed begins to grow, its first root is called a primary root.
This branches into secondary roots.
Roots are protected at the end by a thimble shaped root cap as they probe through the soil.
How plants live On every root there are tiny hairs that help it to take up water and minerals.
Some plants, such as carrots, have a single large root, called a taproot, with just a few fine roots branching off.
Some plants, such as grass, have lots of small roots, called fibrous roots, branching off in all directions.
Some kinds of orchid that live on trees have ‘aerial’ roots that cling to the branches.
Mistletoe has roots that penetrate its host tree.
Roots are delicious when boiled or pickled. The roots of the South African wild fig tree can grow 120 m down into the ground.