Plant Classification & Anatomy

Plants can be classified into 2 main groups: Non-Vascular Plants mosses = no vascular systems Vascular Plants Gymnosperms = complex vascular system + bare seed (cone) (needle trees, conifers) Angiosperm = complex vascular system + enclosed seed within a flower (leaf trees, deciduous)

Two types of Vascular Plants ~ P. 531 1. Monocot - Seed: eg. Corn, 1 cotyledon (seed leaf) - Stem: Vascular bundles scattered in pith - Petals: Multiples of 3 (trillium) - Leaf: Veins run parallel through leaf -Roots: Fibrous

Monocot and Dicot Leaves

Two types of Vascular Plants ~ P. 531 2. Dicot - Seed: eg. Peanut, 2 cotyledons - Stem: Vascular bundles in a ring - Petals: Multiples of 4 or 5 - Leaf: Veins are “net” like - Roots: tap root

Roots Two types: Tap root system – one main root; may have secondary roots 2. Fibrous root system – many finer roots; could grow shallow or deep

Functions of Roots Absorb water and dissolved minerals Anchor plant in the ground Storage for extra food (carrot, beet, etc.) In some cases, can reproduce the plant (hops, dahlias, etc.)

Cool Roots YouTube “Attenborough Strangler Fig”

Stems Herbaceous – green & soft, don’t survive the winter Woody – tough & hard, survive winter (trees)

Functions of Stems Hold up leaves, expose them to light Support reproductive parts (flowers) Conduct materials between roots and leaves Storage in some plants (celery, sugar cane, etc.) Reproduce some plants (strawberry, willow, etc.)

Nice stems! YouTube: “Giant Sequoias” “baobab tree”

Tree Ring Circus Each year, vascular cambium makes new xylem (annual rings) and new phloem Dead phloem will become cork and eventually bark A tree “ring” is made up of spring wood (lots of water, large cells, quick growth) and summer wood (low water, small cells, slow growth)

Tree Ring Circus

Vascular Cambium

Functions of Leaves Photosynthesis (green leaves) Gas exchange (O2 and CO2) Remove excess water (transpiration) Food storage in some plants Reproduction in some plants

Cool Leaves YouTube “mimosa pudica” “attenborough venus flytrap”

Parts of the flower: filament - stalk anther – produces pollen grains Male reproductive part = stamen which are made up of… filament - stalk anther – produces pollen grains Female reproductive part = Pistil which is made up of… style – stalk stigma – sticky surface at tip of style ovary – organ that contain the egg style

Pollination Pollen grain moves from anther to pistil. The grain forms a tube and pollen travels down it to the egg in the ovary. There is a different pollen grain for each egg. Each fertilized egg becomes a seed. The ovary wall becomes the flesh of the fruit.

You Tube clips…flowers & pollination Attenborough- Giant Water Lilies Titan Arum Pitcher plant