Transcript Botany - Ursuline High School

Botany
Review
Kingdom Plantae
General Characteristics
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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
Reactants
C6H12O6 + 6O2
Products
Factors that Affect Photosynthesis
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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 Plants
Bryophytes –
• 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 the
Flowering Plants.
Angiosperms are divided into two groups:
Monocotyledons (Monocots)
and
Dicotyledons (Dicots)
4 Differences between
Monocots and Dicots
Monocots
Leaves – parallel veins
Petals - multiples of 3
Seeds - one cotyledon
Dicots
netted veins
multiples of 4 or 5
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.
Venation of Leaves
Monocots
venation is parallel
Dicots
venation is netted
Number of Petals
Monocots
multiples of 3
Dicots
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
Stem Types
Herbaceous –
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
stimuli
A Positive (+) response is “toward” to stimuli
Phototropism – a plant’s response to light
Gravitropism – a plant’s response to gravity
Hydrotropism – a plant’s response to water
Chemotropism – a plant’s response to
chemicals
Thigmotropism – 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