PLANTS L.E. Bio. Unit 7

Bryophytes Simple roots, stems, and leaves No vascular tissue (xylem and phloem). Short plants. Ex. mosses & liverworts have simple roots called _______. Rhizoids Moss Liverworts

Rhizoids

Tracheophytes Vascular Plants – “true” stems, roots and leaves. w/xylem and phloem, tall plants. ex. ferns Spermatophytes: tracheophytes, seed plants Types: Angiosperms: enclosed seeds, flowering plants, decidous ex. Maple, oak Gymnosperms: naked seed plants, non-flowering, retain leaves ex. Evergreen, pine, conifers.

Angiosperms flowering, covered seed, deciduous

Gymnosperms naked seed, conifers, evergreens, retain leaves

Transpiration: The evaporation of water through the stomates and lenticels of plants Stomata Lenticels

Roots: Drawing:LD S3: 27174 1. Region of Maturation or Specialization 4. Root Hairs 3. Xylem 5. Cortex 5.5 Region of Elongation 2. Epidermal Cells 9. Region of Cell Division 6. Phloem 8. Root Cap 7. Apical Meristem Cell Division

Roots: Region/Zone of Cell Division- Region/Zone of Elongation- Mitotic activity, cells multiply here. Region/Zone of Elongation- Cells elongate and become longer. Region/Zone of Maturation/Specialization- Abundant root hairs, cells differentiate-become specialized

Roots: Root cap- Root Hairs- LD S3: 1931 Covers and protects the end of the root tip, thick walled dead cells. Root Hairs- LD S3: 1931 Projections of epidermal cells. Absorb water and minerals from soil be osmosis, diffusion and active transport.

The “Root” of the Matter

Vascular Tissues Xylem- Phloem- Tubes that transport water upwards from roots to leaves. Makes up wood. Phloem- Tubes that transport food (glucose) downward from leaves to roots.

Functions of Roots Anchorage Transport (xylem & phloem) Absorption of water and minerals Storage (starch) Cortex

Anchorage

Lab 24 Parts 1-3 Roots

Lab 24 Structure of Roots and Stems parts 1-3 Vocab. Part 1 Apical meristem Herbaceous stem Woody stem Allium Ranunculus Zea mays Meristem Zone of elongation Zone of maturation Root cap Part II Endodermis Xylem Phloem Pericycle Vascular cylinder Cortex Epidermis Starch grains Part III Root hairs

Lab 24 Structure of Roots and Stems Monocot. Dicot.

Ranunculus Root C.S. micro.

Ranunculus Root C.S.

Ranunculus Vascular Cylinder

Ranunculus Vascular Cylinder

Ranunculus root C.S.

Stems

Stem Structure 6. Epidermis 5. Phloem 1. Xylem 3. Cambium 2. Pith 4. Annular Rings

Parts of a Stem Bark consists of: Epidermis, Phloem, Cambium

Annual Growth Rings How many years is shown by this tree section ?

Growth Tissues Cambium (Lateral meristem) Apical meristem Causes increase in diameter Two types Vascular cambium-makes new xylem and phloem Cork cambium-makes new cork Apical meristem Causes increase in length Found at stem and root tips.

Functions of Stems: Support Transport Storage Some photosynthesis Some Respiration

Go to Lab 24 Part 4 Stems

Lab 24 Structure of Roots and Stems part 4 Part IV Vocab Parenchyma Vascular bundles Cortex Vascular cambium Pith

Zea Mays Stem C.S.                                                                                                                    

Vascular Bundle of monocot (Zea mays)                                                                                                                                                                                                                 

Dicot Stem Ranunculus

Dicot Stem Ranunculus

Leaves

Leaf Cross Section 16. Upper epidermis 4. Cuticle 5. Palisade Mesophyll 6. Spongy Mesophyll 1. Vein Air space 8. Guard Cell 14. Cuticle 7. Lower Epidermis 15. Spongy Mesophyll 9. Stomata

Another view

LEAVES: Epidermis- Palisade Layer (Mesophyll)- Secrets a waxy cuticle layer No chloroplasts One cell thick Lower contains stomates and guard cells Palisade Layer (Mesophyll)- Main region of photosynthesis. Just under upper epidermis. Dense layer of cells w/ chloroplasts. Spongy Layer (Mesophyll)- Underneath palisade layer-fewer chloroplasts less photosynthesis. Air spaces, storage and diffusion of gases.

LEAVES: Veins-composed of Guard Cells and Stomates- Xylem & Phloem Control the exchange of gasses with the atmosphere. Oxygen, Carbon Dioxide, Water Open during day, closed at night.

Extras See Handout

Lenticels Lenticels

Tropisms

TROPISMS The response of a plant or animal to a stimulus                                                    TROPISMS The response of a plant or animal to a stimulus Caused by an unequal distribution of auxins Auxin = Plant hormone http://www.botanical-online.com/animation8.htm

Phototropism

Phototropism

Geotropism