BotanyReview

Kingdom PlantaeGeneral Characteristics

• Contain Chlorophyll a• Multicellular• Made up of Eukaryotic Cells• Photosynthetic Autotrophs• Cell Walls made of Cellulose

(polysaccharide)• Produce sugars as glucose, transport sugars

as sucrose and store sugars as starch (a polysaccharide).

Review of Photosynthesis

Photosynthesis is the process by which plants use the energy of sunlight to combine carbon

dioxide and water to form glucose and oxygen.

Light Energy + 6CO2 + 6H20 C6H12O6 + 6O2

Reactants Products

Factors that Affect Photosynthesis

• Amount of available Sunlight

• Amount of available Water (rainfall)

• Amount of Carbon Dioxide

• Optimal Temperatures

Adaptations plants made to survive on land

• Developed Cuticles – waxy, protective outer coverings which prevent water loss.

• Developed vascular tissues for transportation of water and sugars.

• Developed spores/seeds for reproduction.

• Developed tissues to strengthen stems to overcome gravity.

The Classification of PlantsBryophytes – • are described as plants that lack xylem and

phloem (vascular tissue)

Tracheophytes –• are plants that have xylem and phloem

(vascular tissue)

Xylem is a type of vascular tissue that transports water upward from the roots to the leaves.

Phloem is a type of vascular tissue that transports sugars (nutrients) from the leaves downward

The Tracheophytes are divide into five groups….

The largest of the five groups are the:

Non-Seed Bearing Plants

And

Seed Bearing Plants

The Seed Bearing Plants are divided into two

groups:

Gymnosperms

(naked-seed Plants)

and

Angiosperms

(encased-seed plants)

The Angiosperms are theFlowering Plants.

Angiosperms are divided into two groups:

Monocotyledons (Monocots)

and

Dicotyledons (Dicots)

4 Differences betweenMonocots and Dicots

Monocots DicotsLeaves – parallel veins netted veinsPetals - multiples of 3 multiples of 4 or 5Seeds - one cotyledon two cotyledons

Vascular tissues in a monocot stem are arranged randomly and look like “monkey faces”.

Vascular tissues in a dicot stem are arranged in a ring surrounding the pith.

Monocots Dicots

venation is parallel venation is netted

Venation of Leaves

Number of Petals

Monocots Dicots multiples of 3 multiples of 4 or 5

New Information!

Seasonal Adaptations

Evergreens –

• plants that remain green year round….

• Pine trees

Deciduous –

• plants that lose all their leaves all at one time….

• Apple trees, grapes

Short and Long Day Plants• Short-day Plants –

Flower when the days are shorter than 12 hours… like onions, garlic, chrysanthemums

• Long-day Plants - Flower when the days are longer than 12 hours… like tomatoes and beans.

Growth Cycles(from seed to seed)

• Annuals – complete their entire life cycle in one growing season. Example: mums

• Biennials – complete their entire life cycle in two growing seasons. Example: Broccoli

• Perennials – continue to grow year after year…. Example: Apple trees can live for 80 years.

Stem TypesHerbaceous – Green, soft….will wilt if water loss

is extreme…. Sour grass, celery

Woody – Brown, rigid…. Will remain erect

even after they are dead….

Trees, roses

Tropisms are the responses plants have to stimuli.

A Negative (-) response is “away” from the stimuliA Positive (+) response is “toward” to stimuli

Phototropism – a plant’s response to lightGravitropism – a plant’s response to gravityHydrotropism – a plant’s response to waterChemotropism – a plant’s response to

chemicalsThigmotropism – a plant’s response to touch

Phototropism a plant’s response to light

Gravitropism - (also called Geotropism) a plant’s response to gravity

A Corn Root responds positively to gravity

Thigmotropism a plant’s response to touch…the tendrils of a

bean plant wraps around a garden post.

Plant Hormones

• Cytokinins – stimulate cell division, and promote the germination of dormant seeds

• Auxins – are involved in plant-cell elongation, apical dominance, & rooting

• Gibberillins – promotes shoot growth, “bolting”, and seed germination