1. Evolution of Plants
1.1. Scientists have come up with a method to classify plants that operates somewhat like a dichotomous key
1.2. Non-Vascular Plants
1.2.1. Short
1.2.2. No vessel system to transport water & nutrients
1.2.3. no true leaves, roots, stems
1.2.4. depend on diffusion, osmosis & active transport
1.2.5. grow close to each other - help reproduce
1.2.6. lack specialized tissue
1.3. Vascular Plants
1.3.1. specialized tissue
1.3.2. tall
1.3.3. have vascular system - transport water and nutrients
1.3.4. can live away from water source
1.3.5. have xylem and phloem
1.4. Seedless Plants
1.4.1. windblown spores
1.4.2. moist areas
1.4.2.1. ferns & horsetails
1.4.3. no seeds
1.5. Seeded Plants
1.5.1. embryo surrounded by seed coat
1.5.1.1. grown into new flower, etc
1.5.2. nutrients inside see
1.6. Gymnosperm
1.6.1. long thin needles- no leaves
1.6.2. cone bearing
1.6.3. don't produce seeds or fruit
1.6.4. generally trees
1.6.5. harsher environments
1.6.6. wide root system
1.7. Angiosperm
1.7.1. difference between angiosperm & gymnosperm
1.7.2. mostly flowering
1.7.3. bear fruit - disperse seeds
1.7.4. feed people
1.7.5. various climates
1.7.6. most abundant plants on earth
1.8. Monocot vs. Dicot
1.8.1. Monocot vs dicot
2. Structure of Roots
2.1. Differences between Monocot and Diocot
2.1.1. Monocot: *Embryo with single cotyledon *Pollen with single furrow or pore *Flower parts in multiples of three *Major leaf veins parallel *Stem vascular bundles scattered *Roots are adventitious *Secondary growth absent
2.1.1.1. Diagram of monocot root
2.1.2. Dicot: *Embryo with two cotyledons *Pollen with three furrows or pores *Flower parts in multiples of four or five *Major leaf veins reticulated *Stem vascular bundles in a ring *Roots develop from radicle *Secondary growth often present
2.1.2.1. Number of Number of Cotyledons
2.1.2.2. ARRANGEMENT OF VAscular Bundles
2.1.2.3. Number of Petals
2.1.2.3.1. s
2.1.2.4. Structure of Roots
2.1.2.4.1. ROOTS
2.1.2.5. STRUCTURE OF LEAVES
2.1.2.5.1. LEAVES
2.1.3. Difference between monocot & dicot
2.2. Root Structure
2.2.1. The meristematic zone
2.2.1.1. the plant cells undergo rapid mitotic division, creating new cells for root growth.
2.2.2. The zone of elongation,
2.2.2.1. begin to elongate, furnishing the root with added length.
2.2.3. The zone of differentiation
2.2.3.1. contains mature, specialized cells, such as phloem, xylem, & root hairs
2.2.4. Dicot Root Picture
2.2.4.1. Monocot Root Picture
2.2.5. PRIMARY ROOT
2.2.5.1. first root
2.2.6. SECONDARY ROOT
2.2.6.1. secondary branches
2.2.7. Crosssection
2.2.7.1. .
3. Structure of Stems
3.1. Herbaceous plants
3.1.1. plants with very flexible stems
3.1.2. leaves &stems die down to soil level at the end of every growing season
3.2. Woody plants
3.2.1. plants with very strong & not easily bendable stems
3.2.1.1. BARK
3.2.2. Woody plants produce wood as a structural tissue.
3.3. Monocot Stem
3.3.1. ontains scattered vascular bundles across the stem
3.3.1.1. .
3.4. Dicot stem
3.4.1. contains vascular bundles arranged in the form of one or two rings
3.5. Function of the Stem
3.5.1. 3 tissues
3.5.1.1. 1. Epidermis
3.5.1.2. 2. Vascular
3.5.1.3. 3. Ground
3.5.2. Vascular bundles
3.5.2.1. Zylem & Phloem carry water & nutrients up and down
3.6. meristematic region - at the tip of each shoot
3.7. elongation - an area below it where the cells grow
3.8. primary tissues develop into xylem and phloem etc
3.9. Vascular bundles - made of xylem and phloem
4. ROOTS FUNCTION
4.1. ANCHOR plant & provide support
4.2. absorb water & minerals from soil
4.3. Store Carbs
4.4. produce compounds like hormones
5. STEM FUNCTION
5.1. store water and carbohydrates
5.2. provide support
5.3. transport link to and from leaves, roots & repro. parts
6. Plant
6.1. .
6.1.1. TISSUES
6.1.1.1. 5 Functions
6.1.1.1.1. .absorption, transport, storage, photosynthesis, and reproduction
6.1.1.2. 4 Types
6.1.1.2.1. meristem, dermal, ground and vascular
7. Succession
7.1. -the process of change in the species structure of an ecological community over time
7.1.1. PRIMARY SUCCESSION
7.1.1.1. beginning of a community, barren rock etc
7.1.1.2. plants fight to grow
7.1.1.3. pioneer species start
7.1.2. SECONDARY SUCCESSION
7.1.2.1. recolonization
7.1.2.2. soil remains intact
7.2. time scale can be decades, or even millions of years after a mass extinction
7.2.1. ECOLOGICAL CHANGE
7.2.1.1. opportunity for new plant growth
7.2.1.2. biodiversity
7.2.1.3. EXAMPLE - tree falling - plants around get sunlight
8. HORMONES
8.1. a chemical produced in one part of an organism, transported to other tissues where it has its effect
8.1.1. .
8.2. produced in response to a stimuli
9. How plants respond to their environment
9.1. Nastic response
9.1.1. *direction of nastic movements is independent of the stimulus's position. *may or maynot be growth movement
9.1.2. EXAMPLE: opening & closing of petal
9.2. Tropic response
9.2.1. *growth movement *the direction of tropic responses depends on the direction of the stimulus,
9.2.1.1. Positive tropism
9.2.1.1.1. movement or growth towards a stimulus.
9.2.1.2. Negative tropism
9.2.1.2.1. Negative tropism is the movement or growth away from a stimulus.
9.2.1.3. Phototropism - LIGHT
9.2.1.3.1. plants respond to the sunlight l
9.2.1.3.2. unequal distribution of auxins
9.2.1.3.3. towards light - photosynthesis
9.2.1.4. Geotropism - GRAVITY
9.2.1.4.1. -plants fights gravity -plants natural growth response to the effects of gravity
9.2.1.4.2. stem - negative response by growing against gravity
9.2.1.4.3. roots - positive response by growing towards gravitational pull
9.2.1.4.4. Auxin concentration- increases along the lower sides of the roots and stems
9.2.1.5. Thigmotropism - MECHANICAL STIMULUS
9.2.1.5.1. -plants grow in response to the touch and contact
9.2.1.5.2. winding
9.3. Macronutrients
9.3.1. needed in LARGE amounts , big picture nutrition categories,
9.3.1.1. carbohydrates, fats, and proteins
9.4. Micronutrients
9.4.1. needed in SMALL amounts
9.4.1.1. in. vitamins and minerals like calcium, zinc, and vitamin B-6.
9.5. Sensitivity
9.5.1. ability to detect change and to respond
9.6. Response
9.6.1. a form of defence that allows organisms to survive.
9.7. PH SCALE
9.7.1. acids & bases
9.8. .
10. Plant Growth and Hormones
10.1. Auxins
10.1.1. stimulate cell division & elongation in stems and roots
10.1.2. relegate cell expansion in plant responses to light & gravity.
10.1.3. -essential for developing leaves & seeds. --create short tips.
10.2. Cytokinins
10.2.1. stimulate cell division
10.2.2. prevents the ageing of leaves.
10.2.3. They create root tips
10.3. Gibberellins
10.3.1. stimulate cell elongation & stimulate seed germination.
10.3.2. create young shoots & develop seeds.
10.4. Ethylene
10.4.1. promotes ripening of fruit
10.4.2. in all part part of plants, especially when under stress, ageing or ripening.
10.5. Abscisic Acid
10.5.1. induces & maintains seed dormancy.
10.5.2. inhibits shoot growth closes the stomata.
10.5.3. leaves the plant under noticeable stress
10.6. TOPIARY -
10.6.1. Cytokinins – this hormone prevents leaves from aging
10.6.1.1. used to promote plant growth,
10.6.1.2. when a lot of it is applied it can be used as a weed killer
10.6.2. Abscisic acid – this hormone maintains and induces seed dormancy (limiting growth)
11. Structure of Leaves
11.1. Function of Leaves
11.1.1. produce food for the plant by photosynthesis.
11.1.2. Chlorophyll, gives plants green colour, absorbs light energy.
11.2. Photosynthesis
11.2.1. -process by which green plants & certain other organisms transform light energy into chemical energy.
11.2.1.1. .
11.2.1.1.1. .
11.2.2. Photosynthesis requires: 1. Light 2. CO2 3. Water, minerals
11.2.3. How leaf gets: 1. Chlorophyll captures light (makes leaf green) Leaf has a large surface area. 2. Guard cells in leaf allow gases to enter via stoma. 3. Veins (xylem) are extensions of the stem’s vascular system
11.3. Monocot Leaf
11.3.1. characterized by their parallel veins.
11.4. Dicot Leaf
11.4.1. do NOT have parallel veins but have branching veins.
11.5. Key Terms
11.5.1. Epidermis
11.5.1.1. upper & lower epidermis
11.5.1.2. aids in regulation of gas exchange
11.5.1.3. one layer - but may have more to prevent transpiration
11.5.2. Vein
11.5.2.1. vascular tissue
11.5.2.2. .
11.5.2.2.1. in the spongy layer of the mesophyll.
11.5.2.3. venation - pattern of veins
11.5.2.4. phloem - cells bring water & minerals from roots into leaf
11.5.3. Mesophyll
11.5.3.1. 2 layers of cells
11.5.3.1.1. palisade parenchyma -
11.5.4. Cuticle
11.5.4.1. reduces the rate of water loss from the leaf surface
11.5.4.2. blocking air flow across the leaf surface.
11.5.5. Stomata
11.5.5.1. involved in exchange of CO2 & water between plants & atmosphere.
11.5.5.1.1. Open during photosynthesis
11.5.5.2. in epidermis
11.5.6. Guard cell
11.5.6.1. in the leaf epidermis
11.5.6.2. pairs surround & form stomatal pores
11.5.6.2.1. regulate CO2 mix
11.5.7. Fighting gravity
11.5.7.1. osmosis (root pressure),
11.5.7.2. transpiration (evaporation in leaves),
11.5.7.3. cohesion tension (natural attraction of polar molecules for other polar molecules).
11.5.8. Transportation of food
11.5.8.1. .
12. GROWTH -adapt to new situations by modifying growth, by chemicals called growth regulators (hormones_
12.1. Meristems:
12.1.1. regions of active cell division
12.1.2. tips of plants