Unit 7 Chapter 23 Plant Structure and Function - PowerPoint PPT Presentation

1 / 22
About This Presentation
Title:

Unit 7 Chapter 23 Plant Structure and Function

Description:

Unit 7 Chapter 23 Plant Structure and Function Plant Tissues 1) Dermal Tissue For covering and protection, and controlling water loss Examples: epidermis, including ... – PowerPoint PPT presentation

Number of Views:207
Avg rating:3.0/5.0
Slides: 23
Provided by: pflugervi
Category:

less

Transcript and Presenter's Notes

Title: Unit 7 Chapter 23 Plant Structure and Function


1
Unit 7Chapter 23Plant Structure and Function
2
Typical plant cell
3
Plant Tissues
  • 1) Dermal Tissue
  • For covering and protection, and controlling
    water loss
  • Examples epidermis, including cuticle of leaves,
    guard cells stomata

4
Plant Tissues
  • 2) Vascular tissue
  • For transport of food, minerals and water
  • Examples
  • Xylem (for transporting upward from roots)
  • Phloem (for transporting downward from leaves)

Phloem
Xylem
5
Plant Tissues
cortex
  • 3) Ground tissue
  • For storage, food production, strengthening and
    support
  • Examples cortex, pith, mesophyll

pith
6
Plant Tissues
Apical Meristem of Shoot
  • 4) Meristematic tissue
  • For production of new cells
  • Examples growing tips in roots and stems (shoots)

7
Roots
  • To anchor, absorb, and conduct
  • Types of root systems
  • 1) taproot
  • One main root with branches
  • Ex carrot
  • 2) fibrous
  • Many small branching roots
  • Ex grass

8
Root Structure
  • 1) Root cap
  • Protective covering of root tip
  • 2) Apical Meristem
  • Region of cell division (where mitosis occurs)

9
Root Structure
cortex
  • 3) Epidermis
  • May contain root hairs for increasing surface
    area
  • 4) Cortex
  • Ground tissue for storage of food and water

10
Root Structure
  • 5) Endodermis
  • Waterproof cells that control flow
    of water into vascular
    tissue
  • 6) Pericycle
  • Produces lateral roots

11
Root Structure
  • 7) Xylem (star-shaped
    center)
  • Transports water upward
  • 8) Phloem
    (between rays of star)
  • Transport food downward

12
Stems
  • To support, conduct, and store
  • Arrangement of Vascular Bundles
  • Monocots
  • Randomly scattered
  • Dicots
  • Radially arranged

Can you classify these stems?
13
Woody stems
  • Bark
  • Composed of cork, phloem, vascular cambium
  • Wood
  • Composed entirely of xylem tissue
  • Contains annual growth rings
  • Pith (young stems)

Pith
14
Pith
15
Translocation
  • The movement of sugars through the phloem, from
    the source (origin) to the sink (storage area,
    such as root or fruit)

16
Leaves
  • For photosynthesis and transpiration
  • 1) Blade (flat green portion)
  • Simple
  • One undivided blade
  • Compound
  • Blade divided into leaflets
  • 2) Petiole (stalk)
  • Contains vascular tissue, attaches to stem

17
Leaf structure
  • 3) Epidermis
  • Upper epidermis produces waxy cuticle to prevent
    water loss
  • Lower epidermis contains guard cells stomata to
    control water loss

cuticle


18
Leaf structure
  • 4) Mesophyll
  • Photosynthetic tissue
    made up of palisade
    spongy cells
  • 5) Veins
  • Contains xylem phloem cells




19
Transpiration
  • Evaporation of water through stomata
  • Plants lose 90 of the water they transport from
    the roots by transpiration. What happens to the
    other 10?
  • When water enters the
    guard cells, pressure
    causes them to bow,
    opening
    the stoma
  • When water leaves the
    guard cells, pressure
    is lost
    and the cells come
    together, closing the stoma

20
Plant hormones
  • Like animals, plants produce hormones to regulate
    growth
    development
  • Hormones are chemicals
    produced in one part and
    transported to another to
    effect a change
  • Examples of plant hormones
    are Auxin, Gibberellins,
    Cytokinins, Ethylene

(Without) (With) Gibberellin
21
Tropic responses in plants
  • Tropism is a plants response toward a stimulus,
    such as gravity (gravitropism), light
    (phototropism) or touch (thigmotropism)
  • Ex phototropism
    is the growth of a
    plant toward light

22
Nastic responses in plants
  • Nastic movements are NOT dependent on the
    direction of the stimulus
  • For example in a Venuss fly-trap,
    the insect
    triggers
    sensitive hairs on
    the surface and the
    leaf snaps shut
Write a Comment
User Comments (0)
About PowerShow.com