3. Plant Structure and Function Flashcards
What are plants shoots and what do they consist of
Above ground. They have stems and leaves.
What portion does roots have to do with
Below ground
Draw a plant structure diagram
.
What are the function of leaves (4)
Photosynthesis - production of sugar from co2 and h2o in the presence of sunlight. occurs in chloroplast that contain chlorophyll
Storage of food and water.
Leaves have an epidermis (outer layer of cells) covered by a waxy cuticle (prevents water loss). Leaves also have stomata (openings)
Name leaves that store food
Onion. Aloe vera stores water and cactus.
Functions of stems (6)
- Allows for continued growth of plant vertically (indeterminate). Grow for many years = perennial (also means indeterminate). To grow for only one year = annual.
- Provide physical support to the plant
Oldest tree?
Oldest trees are 4,750 yrs old.
Functions of stems (6)
- Allows for continued growth of plant vertically (indeterminate). Grow for many years = perennial (also means indeterminate). To grow for only one year = annual.
- Provide physical support to the plant
- Provide axillary buds that produce side shoots (brussel sprouts)
- Transport water & nutrients up and down plant
- May be used for storage of food & h20
- Allow for lateral growth to increase size of trees in diameter
Oldest tree?
Oldest trees are 4,750 yrs old.
Function of roots (5)
- To anchor plant/tree in soil
- To absorb h20 & nutrients from soil. Roots have a very large SA
- To provide continued growth via root tips (meristem)
- For storage of nutrients e.g. carrots
- Epidermis on root protects the root
Plant cells vs. Animal cells
- Plants have choloroplasts
- Plant cells have thick cell walls
- Plants have vacuoles (storage of water, nutrients, waste products)
Describe plants cell wall
- Multilayered cell wall
- Primary cell wall contains cellulose (chain of glucose molecules)
- Secondary cell wall has lignin and hemicellulose (provides strength and rigidity)
- Cells connected to one another by cytoplasmic connections by plasmodesmata
Function of cellulose and lignin
Thickening and strength
Two species of plants
1) Coniferous species (evergreens) -> gymnosperms (cedar, fir, hemlock, pine)
2) Deciduous species (flowering plants) -> angiosperms (250,000 species)
Two species of plants
1) Coniferous species (evergreens) -> gymnosperms (cedar, fir, hemlock, pine)
2) Deciduous species (flowering plants) -> angiosperms (250,000 species)
Angiosperms are divided into what two categories
Monocotyledons (monocots) & dicotyledons (eudicots)
Differences between monocots and dicots
Monocots have one cotyledon, eudicots have two. Leaf veins on monocot are parallel, but branche on eudicots. Monocot’s flowers come in multiples of 3, dicot’s flowers come in multiples of 4-5. Vascular bundles of monocots are arranged randomly, vascular bundles of dicots are circular. Root system of monocots are fibrous, taproot for dicots.
List 4 types of plant tissue
Meristermatic, Dermal, Vascular and Ground tissue
Describe meristematic tissue
Actively dividing cells, found in growing points (top of plant, root tip)
Continued growth is possible = primary growth
Describe meristematic tissue
Actively dividing cells, found in growing points (top of plant, root tip)
Continued growth is possible = primary growth
Describe dermal tissue
On outside of plant (epidermis)
Protective role
Describe ground tissue
3 types
a) Parenchyma
- most common
- thin walls
- large vacuole
- make food (sucrose) i.e. leaves
- store food (sucrose, starch) i.e. fruits roots
- living cells
b) Collenchyma
- no food production
- supportive function: thicker cell walls
- living cells
- maintain rigidity in plant
- example is celery
c) Sclerenchyma
Describe ground tissue
3 types
a) Parenchyma
- most common
- thin walls
- large vacuole
- make food (sucrose) i.e. leaves
- store food (sucrose, starch) i.e. fruits roots
- living cells
b) Collenchyma
- no food production
- supportive function: thicker cell walls
- living cells
- maintain rigidity in plant
- example is celery
c) Sclerenchyma
- thick cell walls
- very important for support (physical)
- dead cells
- trees and plants grow upright
Describe vascular tissue
2 types
a) Xylem
- transport of h20 and nutrients up the plant
- dead, lignified cells
- provides structural support (trees)
- Main cells are tracheids and vessel elements. Vessel elements are shorter, and are connected together into long tubes that are called vessels
b) Phloem
- transport of sugar to top and bottom of plant
- alive and nonlignified
- Main cell are Sieve Tube Elements that has a sieve plate across top and companion cell beside
Describe vascular tissue
2 types
a) Xylem
- transport of h20 and nutrients up the plant
- dead, lignified cells
- provides structural support (trees)
- Main cells are tracheids and vessel elements. Vessel elements are shorter, and are connected together into long tubes that are called vessels
b) Phloem
- transport of sugar to top and bottom of plant
- alive and nonlignified
- Main cell are Sieve Tube Elements that has a sieve plate across top and companion cell beside
Describe lateral growth
Secondary growth, causes increase in diameter
What is vascular cabium
Actively dividing layer of cells in stems
What is vascular cabium
Actively dividing layer of cells in stems
Describe plant transport
Move water from soil, up stem and leaves Roots take up water and move in xylem Move sugar down from leaves in phloem Root hairs increase SA in absorbtion Nutrients are taken up
Two types of nutrients and describe them
1) Macronutrients
a) needed in high concentrations
- includes nitrogen, potassium, sodium
b) Micronutrients
- needed in low concentrations
- iron, copper, zinc
Describe uptake of nutrients in roots
Anions - negatively charged, easy to take up
Cations - positively charged, binds to soil particles
Describe uptake of nutrients in roots
Anions - negatively charged, easy to take up
Cations - positively charged, binds to soil particles
Release of protons into soil. Cross the cell membrane. Proton pump -> co transport (fig 38.10)
How does water enter root
Apoplast (around cells)
Symplast (through cells)
What is the casparion strip (wax)
Redirects water through cells. Control flow, via symplast.
Characteristics of maple tree
Summer day, 800L/day (30-40 flights), water against gravity