PLANTS

Characteristics Eukaryotic, multicellular, nonmotile Photosynthetic- autotroph Have chloroplast:chlorophyll a and b Cell wall made of cellulose- protects and supports Cuticle- waxy covering that prevents desiccation

Life Cycle 2 alternating cycles 2N- diploid sporophyte 1N Haploid gametophyte

Plant Needs Sunlight Water and minerals Gas Exchange Movement of water and nutrients

Plant Adaptations How did plants move from water to land? Vascular tissue: xylem carries water from roots, phloem carries food made in leaves Cuticle—prevents water loss Roots- anchor the plant, absorbs water and nutrients Pollen- male sperm- doesn’t need water to distribute Seeds- provide protection and food supply to embryo

4 MAIN TYPES OF PLANTS Bryophyte Pterophyte Gymnosperm Angiosperm Common Name MOSSES FERNS PINES FLOWERING Vascular tissue No Yes Male gamete Flagellated sperm Pollen Dominant Generation Gametophyte Sporophyte

Mosses No vascular tissue and produce flagellated sperm- so need to be in close contact with water No roots- rhizoids anchor to ground Peat moss- used for fuel

Ferns Flagellated sperm Has vascular tissue

Gymnosperm Vascular tissue Has male and female cones Male cone produces pollen Female cone produces ovules

Angiosperm Produce flowers Produce seeds within a “fruit” Vascular tissue Green(Herbaceous) or woody stem

2 Types of Angiosperms Monocot- Grasses, lilies Dicot-Shrubs, trees, flowers Annuals- live 1 year, have herbaceous or green stem(replant) Perennial- trees and shrubs Biennial- takes 2 years to grow-root storage like carrots

Monocot vs. Dicot Vascular Bundle in Leaf Vascular Bundle in Stem Cross section Vascular Bundle in Root Cross Section Flower groups Monocot Parallel Scattered Ring 3’s Dicot Web like X 4’s and 5’s

3 Types of Plant Cells Parenchyma- storage and food production Collenchyma- found in areas of current growth Sclerenchyma- thick walled cells used for support, also fiber, and grit in pears

3 Types of Plant Tissues Dermal- makes up epidermis-protects- secretes cuticle Vascular- set of “pipes” that transport materials far distances. Xylem carries water (tracheids and vessel elements) Phloem carries food(sugar)(sieve tube elements and companion cells) 3. Ground – sites of photosynthesis(leaves), storage(roots), and support(stems)

Plant growth Meristematic tissue- site of actively dividing cells(mitosis). Found at tip of shoot(called apical- at the top) and the tip of the root. Apical meristem found at the top of the shoot and bottom of the root.

Plant organs Roots Stems Leaves

Roots help anchor plant, absorb nutrients, have root hairs to increase surface area 2 types- fibrous taproot (food storage like carrot) Monocot (vascular bundle arrangement) Dicot

Root cap at end of the root- protects new ,growing cells Root cap at end of the root- protects new ,growing cells. Also produces lubricant so root can move through soil.

Stems Support the leaves 2 types- herbacous- green woody Monocot (vascular bundle arrangement) Dicot

Leaf Site of photosynthesis

Palisade mesophyll and spongy mesophyll- photosynthesis cells. Spongy mesophyll loosely packed – spaces where the gases can be stored. Vascular bundle contains the xylem and phloem Stomata open during times when water loss is low(early day or late afternoon) Loss of water through stomata called TRANSPIRATION

Stomata- opening in the leaf that allows gas exchange- O2 out and CO2 in for photosynthesis. Guard cells control the opening of the stomata. When guard cells fill with water, stomata open. When water leaves guard cells- stomata are closed.

Water transport What moves water up against gravity? Root pressure- movement of water coming up from the roots Adhesion- water sticks to sides of xylem cells Capillary action- water attracted to itself and the tube Transpiration- when stomata open- help pull the water up- negative pressure

STOMATA

Flowers Reproductive organ of a plant- contains the male and female parts Plants do not self fertilize- mechanisms in place that doesn’t allow it. Male- stamen (anther and filament) Female –carpel (stigma, style and ovary) Petals- attract pollinator Sepal- green leaf surrounding flower

Plant Hormones Auxin- cell elongation Gibberellins- promote growth Cytokinin- stimulate cell division,growth of lateral buds Ethylene gas- promotes fruit ripening

Tropism- plant response to external stimulus like light or gravity Thigmotropism- response to touch-vines

Photoperiodism Short Day Plants Long Day Plants Short day, long night Can interrupt night to stop flowering Poinsettia Long day, short night Increase night to stop flowering Iris