Transcript Kingdom Plantae

Kingdom
Plantae
General Characteristics:
• Eukaryotes
• Multicellular; organized
into tissues, organs and
systems
• Cell walls present
(cellulose)
• Autotrophs; contain
chloroplasts
• Reproduce sexually
General Characteristics
What Plants need:
– Sunlight to carry out photosynthesis
– Water and minerals
– Gas exchange (oxygen for respiration; carbon dioxide
for photosynthesis)
– Movement of water and nutrients
Origin:
• Probably descendants of
green algae (Protist)
• Algae always live in
water, which supports
nutrient transport &
absorption, stable
environment, gamete
transfer & development,
and structural support.
Origin:
• Life on land requires many
adaptations
– protection from drying out
– gas exchange with surrounding
air
– transport for water & nutrients
through multicellular body
– support to grow upright on land
Adaptations & Specialized Structures:
• Cuticle – a waxy layer from the
outer epidermis of the plant
surface that prevents water loss to
the external environment
(osmosis)
• Stomata – small openings on the
leaf surface to allow gas exchange
• Guard Cells – surround the
stomata to control the opening
and closing of the pore
Adaptations & Specialized Structures:
• Vascular Tissues – tubes that allow
transport of water and nutrients to
different parts of the plant; form
vascular bundles throughout the
plant
* Xylem – transport water and
minerals up from the roots
throughout the plant
* Phloem – transport food
(sugars) from the leaves and
stems, where it is made, to other
parts for use or storage
Adaptations & Specialized Structures:
* Cambium – produces new xylem & phloem
Adaptations & Specialized Structures:
• Cell Walls – rigid structure
provide structural support for
growth on land.
• Roots – specialized tissues
(usually underground) that
absorb water & minerals,
anchor the plant for upward
growth, and store food as
starch
• * Root hairs – extensions that
increase absorption
Adaptations & Specialized Structures:
• Stems – tissues that support the aboveground parts of the plant and allow
movement of materials between leaves and
roots. Also store food.
Adaptations & Specialized Structures:
• Flower – assist in pollination process
by attracting birds and insects with
color or scent. Contain the male and
female reproductive organs.
– * Sepal – protects the young bud
– * Petal – attracts pollinators, serve as a
landing pad
– * Stamen – male reproductive organ
- Anther – produces male
gametes (pollen)
- Filament – supports the anther
Adaptations & Specialized Structures:
• Pistil – female reproductive organ
– Ovary – swollen base of the pistil
where ovules (eggs) are produced
– Style – neck of the pistil, allows for
sperm transfer to ovary
– Stigma – sticky or rough surface at
the tip of the style
• Seed – a plant embryo with a
food supply enclosed in a tough,
protective coat; allows for success
through harsh conditions
Life Cycle of Plants
Alternation of generations:
– haploid gametophyte (gamete producing plant)
– diploid sporophyte (spore producing plant)
Plants can reproduce asexually with leaves,
stems and roots.
– regeneration
– vegetative propagation (stolons, rhizomes, tubers
and bulbs)
Classification within the Kingdom:
Nonvascular Plants – lack the specialized tissues to
transport water
* individuals are very small; only a few cells thick to
allow diffusion of nutrients and water
* grow in clumps or “carpets” in very moist
environments
*depend on water for reproduction
* examples – moss, hornworts and
liverworts (Phyla: bryophytes)
Classification within the
Kingdom:
Vascular Plants – have tube-like tissues to
transport water and nutrients
* requires development of different
tissues (roots, stem, leaves) for success
on land
* allows for upright growth &
development into complex organisms
* simple examples – club moss,
horsetails & ferns
- require growth in moist
environments for sperm dispersal,
produce spores
Classification within the Kingdom:
Gymnosperms – non-flowering vascular plants
* leaves are in the form of needles or scales
* seeds are not enclosed in fruit
* many produce cones to protect seeds (conifers)
* do not produce flowers
* sperm is protected in a hard coat called pollen
and are dispersed by wind
* very hard cell walls allow for tall growth (woody
tissue)
* examples – cycads, pine, fir, spruce, redwood
Classification within the Kingdom:
Angiosperms – flowering vascular
plants
* seeds are enclosed in fruit, a
ripened ovary
* leaves are flat
* have woody and non-woody stems
* divided into 2 groups based on the
number of cotyledons (leaf-like
parts of the plant embryo in the
seed)
Angiosperms
Classification within the Kingdom:
Monocots – one cotyledon on seed
* flower parts in multiples of 3
* vascular bundles scattered throughout the stem
* parallel veins in narrow leaves
* fibrous roots
* examples – grasses, corn, rice, oats, wheat, tulips
Dicots – two cotyledons on seed
* flower parts in multiples of 4 or 5
* vascular bundles form a ring in the stem
* branching, netlike veins in broad leaves
* tap roots
* examples – oak & maple trees, garden flowers, beans, fruit trees,
broccoli, carrots
Monocots vs. Dicots
Tropisms
•Occur when plants respond to external stimuli
•Cause a change in plant growth
•Can be negative (away from stimuli) or positive
(toward stimuli)
Plant Hormones
• Auxin - Stimulates cell elongation; involved in
phototropism, gravitropism, stimulates fruit
development. Too much can prevent growth.
• Abscisic Acid – slows or stops growth and cell
division in plants.
• Gibberellin - Stimulates shoot elongation,
stimulates flowering in biennials.
• Ethylene - Stimulates fruit ripening
Assignment:
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6.
Sketch the general life cycle of plants (p 664)
Sketch and label the structure of a flower.
How do plants obtain energy?
What are the plant tropisms? Give examples.
Draw the cladogram on page 613
What would be the derived characters in this
cladogram?
7. From which organisms did plants evolve? Which
kingdom does that ancestor belong to?
Define the following terms
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Plant
Cuticle
Stomata
Vascular system
Pollen grain
Seed
Pollination
Gymnosperm
Angiosperm
Cone
Flower
Fruit
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Dicot
Xylem
Phloem
Root hair
Fibrous root
Tap root
Guard cell
Alternation of
generations
• Sporophyte
• Gametophyte
• Ovary
•Thigmotropism
•Gravitropism
•Photoperiodism
•Germination
•Regeneration
•Vegetative
reproduction
•Tropism
•Cotyledon
•Monocot
•Phototropism