1. PLANTS Plants play an important role in an ecosystem.
They are autotrophic organisms that carryout photosynthesis 6H2O + 6CO2 + sunlight C6H12O6 + 6O2.

2. PLANT CHARACTERISTICS
Multicellular eukaryotes
Photosynthetic autotrophs containing chloroplasts.
Non-mobile (fixed to one spot)
Cell walls made of cellulose
Responds to environment and grows through the use of hormones

3. The Evolution and Classification of Plants
Plant Diversity
The Evolution and Classification of Plants

4. Plant Overview
Evolution of Kingdom Plantae
Fossil and biochemical evidence indicates plants are descended from multicellular green algae. Between 500 and 400 million years ago, some algae made the transition to land, becoming plants by developing a series of adaptations to help them survive out of the water.

5. Plants Make the The Move to Land
The ancestors of plants were multicellular green algae. They were completely immersed in water & dissolved minerals.
To move onto land, plants had to solve these problems:
How to get chemical resources (water, minerals, oxygen, and carbon dioxide) separated into air and soil
How to transport resources within the plant.
How to prevent from drying out
How to reproduce without water

6. An Adaptation (solution)-
Have body parts extending into both air and soil
Shoot – portion of a plant grows mostly upward and aboveground.
Root – portion of the plant that grows mostly downward and belowground.

7. Some more Adaptations (solutions)-
Develop a vascular system to transport resources in plant
Have a protective layer – cuticle (waxy outer layer) to keep from drying out
Specialized structures for reproduction including spores & seeds that do not dry out

8. Plants are classified based on whether or not they have
Vascular System (transport)
Seeds
Flowers (enclosed seeds)

9. Plants Has NO Vascular Tissue Has Vascular Tissue Bryophytes
Concept Map: Plants are divided 1st by whether or not they have a vascular system.
Nonvascular Plant
Vascular Plant
Plants
Has NO Vascular Tissue
Has Vascular Tissue
Bryophytes
Tracheophytes

10. Bryophytes - NONVASCULAR
Most primitive plants
Found in moist, shady areas
NO vascular (transport) system
Small size due to no vascular tissue
No true roots, stems, or leaves
Needs water for reproduction.
Reproduces using spores, -a water-proof single cell that can grow into a new organism.
Most common example: Mosses

11. Typical Moss Plant (most common bryophyte)
Spores form inside the capsule.
Notice the problem of nutrient separation into air and soil is solved with underground and above ground parts. (Although NO TRUE roots, stems or leaves are present)

12. Tracheophytes -Vascular Plants-
Contains two types of specialized vascular tissues for transport water and other materials in within the plant.
Presence of a vascular system allowed plants to become tall.
Has specialized organs: roots, stems, and leaves.

13. Plant Overview
Xylem - type of vascular tissue in plants that contain hard walled conducting cells that transport water and dissolved minerals upwards from the roots to the leaves.
Phloem -type of vascular tissue in plants that contains soft-walled conducting cells through which organic compounds are transported throughout the body of a plant.

14. Tracheophytes Seeded Seedless Ferns use spores
Tracheophytes are divided into two groups by whether or not they reproduce with seeds.
Tracheophytes
Seeded
Seedless
Ferns use spores

15. There are 11,000 species of ferns.
The Fern - a seedless vascular plant
There are 11,000 species of ferns.
Contain a vascular system.
They grow in moist, shady habitats.
Has underground stems, roots, & large leaves called fronds.
Reproduce using spores, Not seeds.
Sori

16. SEEDLESS VASUCLAR PLANTS DO NOT MAKE SEEDS
Rhizomes – horizontal underground stem.
Cone – in plants, cluster of non-green spore-bearing leaves.

17. Seed-Bearing Tracheophytes
ADVANTAGE: Developed reproductive strategies that do not need water:
Seed contains
A fully developed embryo
Food supply for embryo
A water-proof seed coat to keep from drying out
Sperm transferred in water-proof pollen through pollination by wind or by animals.
Developed seed-bearing structures: Cones and Flowers

18. VASUCLAR TISSUE, SEEDSMADE PLANTS SUCCESSFUL
Seed plants - vascular plant that produces seeds.
Seed – a structure that consists of a plant embryo surrounded by a protective coat.
Embryo – early stage in development of plants and animals

19. Tracheophytes Seeded Seedless Ferns use spores Gymnosperms Angiosperms
The two Seeded Tracheophyte groups are divided by whether or not they have enclosed seeds - protected inside a fruit or if seeds are exposed to the environment.
Tracheophytes
Seeded
Seedless
Ferns use spores
Gymnosperms
Angiosperms
“naked” or exposed seeds
Flowers produce fruit w/ enclosed seeds

20. Gymnosperms - “naked seed”
Cycad (Sago palm),
Ginkgo,
Conifer (pine, spruce, firs, cedars, sequoias, redwoods, junipers, yews, & cypress trees)
Sago Palm
Ginkgo
Ginkgo

21. Gymnosperms-Conifers
Sequoia
Gymnosperms-Conifers
Most common gymnosperms are Conifers
Conifers have leaves called needles or scales have a reduced surface area and thick waxy coat on the needle to reduce water loss and prevents freezing.
Juniper
Pine

22. Conifer Reproduction
Pollen
Male cones produce pollen and the female cone produces eggs and seeds.
Pollen is inefficiently transferred by the wind.
Once mature, the scales on the female cone dry out and open scattering the seeds by the wind.
Seed Cone
Pollen Cone

23. Angiosperms- “enclosed seeds”
These are flowering plants the encourage direct and efficient pollen transfer (smell, color and offering nectar)
Pollinators are flying insects, birds, and bats that transfer pollen from flower to flower.
Flowers contain ovaries, which is where eggs/seeds are produced.
A fruit is the pollinated ovary containing mature seeds.

24. Winged fruit – glides to new location (maple fruit)
Fruit can aid in dispersal of seed to reduce competition with parent plant.
Winged fruit – glides to new location (maple fruit)
Floating fruit – can float to new locations (coconut)
Fleshy fruit - sweet bright colored fruit have seeds that survive the digestive system of animals that eat the fruit (apple)
Spiny fruit- Velcro like projections attach to the fur of animals (cockleburs)
Maple seeds: Winged fruit
Burdock: Spiny fruit

25. Angiosperms- “enclosed seeds”
Monocots and Dicots are types of angiosperms, or flowering plants.
Monocots produce seeds with one seed leaf. Most monocots produce flowers, which have parts that are generally in multiples of three. Monocots have long narrow leaves with parallel veins.
Dicots are flowering plants that produce seeds that have two leaves. Dicots produce flowers, which parts are in multiples of 2,4, or 5. The leaves have branched or netted veins.

26. Structure of
Plants

27. A. Functions of Roots Anchor & support plant in the ground
Absorb water & minerals
Hold soil in place
Fibrous Roots
Root Hairs

28. Root Types
Tap Root
1. Fibrous Roots: branching roots hold soil in place to prevent soil erosion
Ex. Grasses
2. Tap Roots – larger central root reaches deep water sources underground
Ex. Trees, Carrots, & Dandelions

29. The Structure of a Root
Root Hairs
Root Hairs: increase surface area for water & mineral absorption
Meristem: region where new cells are produced
Root Cap: protects tip of growing root
Phloem
Xylem
Meristem
Root Cap

30. Roots – function and structure
Hold plant in position
Absorb water and minerals from the soil
Specialized cells to increase surface area for water intake
Cross Section
Longitudinal Section

31. Wheat seed
Root hairs
Fragile parts of cells that grow from the main root
They massively increase the surface area for absorption

32. Stele or Central Cylinder

33. Functions of Stems Support system for plant body
Transport system carries water & nutrients
Holds leaves & branches upright
Looking at the picture to the left:
What years had the most rain?
What years experienced the worst drought?
Each light and dark tree ring equals one year of annual growth. Light rings for fast spring growth, dark for slow summer growth.
Smaller rings tell of past droughts that have occurred.

34. Functions of Leaves Main photosynthetic organ
Broad, flat surface increases surface area for light absorption
Have systems to prevent water loss
Stomata open in day but close at night or when hot to conserve water
waxy cuticle on surface
System of gas exchange
Allow CO2 in and O2 out of leaf
Elephant Ear Plant

35. LEAVES CARRY OUT PHOTOSNYTHESIS
Petiole - Slender stalk that attaches the blade of a leaf to a stem.

36. Leaf Structures Leaf Cross-Section
Cuticle: waxy layer; covers upper surface
Protects leaf against water loss
Veins: transports water, nutrients and food
Made of xylem and phloem
Mesophyll: contains cells that perform photosynthesis
b/c they contain Chloroplasts.
Cuticle
Veins
Mesophyll
Stoma
(Opening)
2 Guard Cells
Surround
each
Stoma
Stoma- singular
Stomata-plural

37. Leaf Structures
The leaf is a mass of ground and vascular tissue surrounded by an epidermis.
The xylem and phloem make up the veins of a leaf.
Mesophyll in Greek means “in the middle of the leaf”
Most plants have two layers of mesophyll.
The palisade lies beneath the upper epidermis.
The spongy mesophyll lies above the underside of the leaf)
Lower Epidermis are where the stomata are located.

38. More Plant Parts… Guard cells: cells that open and close the stoma
Stomata: openings in leaf’s surface; when open:
GAS EXCHANGE: Allows CO2 in & O2 out of leaf
TRANSPIRATION: Allows excess H2O out of leaf
Guard Cells
Stoma

39. Function of Stomata
Guard Cells
What process involves using CO2 and H2O releasing O2 as a waste product?
Photosynthesis
What is the plant using this process to make?
Carbohydrates-glucose
If the plant needs water for photosynthesis, why is water coming out of the stoma?
Guard Cells
What goes out? O2
H2O
CO2
What goes in?
Stoma Open
Stoma Closed
Stoma

40. Function of Guard Cells
These stomata (leaf openings) naturally allow water to evaporate out.
Why would the plant close stomata with guard cells?
Prevent excess water loss through transpiration. (conserve water)
So what is the point of having stomata?
Allow gas exchange for photosynthesis
Guard Cells
Guard Cells
Guard cells open by inflating with extra water. They do this by pumping K+ ions into the cell, which causes water to rush in via osmosis to diffuse the high ion concentration.
Stoma Open
Stoma Closed

41. Transport of Materials
Capillary Action - the movement of water in upward direction in a small area.
Limitations: Water can move only a few cm up
Root Pressure – H2O moves up by osmosis
Limitations: Only move water about 1 meter
Properties of Water
Cohesion - sticks to itself
Adhesion – sticks to objects

42. Plants find a use for Transpiration
Transpiration: loss
of excess water from plant leaves
2. Significance:
Transpiration causes enough pressure to help pull water (& required nutrients) up stem from roots.
As part of the water cycle, trees transpire water back into the atmosphere.
Transpiration provides much of the daily rain in rainforest.
A average size maple tree can transpire 200 liters of water per hour during the summer.
Transpiration is the #1 driving force for pulling water up stems from roots.

43. Plant Responses and Adaptations

44. Hormone Action on Plants
Hormone-producing
cells
Hormone Action on Plants
A. Plant cells can produce hormones: which are chemical messengers that travel throughout the plant causing other cells called target cells to respond.
B. In plants, hormones control:
Plant growth & development
Plant responses to environment
Movement
of hormone
Target
cells
Cells in one blooming flower signals other blooms using hormones to open.

45. Plant cells will send signals to one another to tell them:
When trees to drop their leaves.
When to start new growth.
When to cause fruit to ripen.
When to cause flowers to bloom.
When to cause seeds to sprout.
Leaf Drop
Tree Budding
Fruit
Ripening
Cactus
Blooming
Sprouting
Corn Seeds

46. Plant Hormones One way that cells can communicate is by hormones.
Membranes contain special cites for receiving the information.
It is the specific shapes of the hormones (shape is unique for each) that the receptors respond to.
Hormone
Effect
Auxin
Stimulates cell elongation on the shaded side of the plant and suppresses growth of lateral buds.
Cytokinins
Stimulates the growth of lateral buds
Gibberellins
Stimulate entire stem elongation by stimulating cell division
Abscisic Acid
Inhibits growth and closes stoma

47. Ethylene causes Fruit to Ripen
Fruit tissues release a small amount of ethlyene
Causes fruits to ripen.
As fruit become ripe, they produce more and more ethlyene, accelerating the ripening process.
Ethylene released by apples and tomatoes causes fruit to age quickly.

48. Plant Tropisms
Tropism: the way a plant grows in response to stimuli in the environment.
Phototropism: growth response to light
-Plants bend towards light
Geotrophism: growth response to gravity
-plant roots grow down with gravity, shoots (stems) grow up against gravity and out of the soil.
Thigmotropism: growth response to touch
-vines grow up around trees, venus flytrap closes when leaves are touched

49. Thigmotrophism Phototropism Thigmotrophism
What type of tropism is shown in these pictures?
Phototropism
Geotropism
Thigmotrophism
Phototropism
Geotropism
Thigmotrophism