1. Characteristics of Plants
Section 12.1

2. Characteristics of Plants
Learning Goal: To explore the basic needs and make up of plants.
Success Criteria:
I know I am succeeding when I can…
explain the basic conditions plants need in order to survive
describe the specific adaptations that allow plants to survive under various conditions
describe the basic structures common to vascular plants and explain the purpose(s) each structure serves
explain the evolutionary relationships among various plant groups

3. Characteristics of Plants
Plants perform the following functions to stay alive:
produce food (glucose) and oxygen using photosynthesis
exchange gases (CO2 and O2) with their surroundings
transport water and nutrients throughout their bodies
grow
reproduce

4. The Phylogeny of Plants
3 major groups of vascular plants:
the lycophytes and pteridophytes (club mosses; ferns and their relatives)
the gymnosperms (conifers)
the angiosperms (flowering plants)
these groups of vascular plants can be distinguished by key evolved traits

5. The Phylogeny of Plants Cont’d…
angiosperms contain cotyledons, which are structures that supply nutrients to the plant embryo
plants with 1 cotyledon are classified as monocots
plants with 2 cotyledons are classified as Amborellales, Nymphaeales, other early angiosperms, or eudicots

6. The Vascular Plant Body: Roots and Shoots
most vascular plants have an underground root system and an above-ground shoot system

7. The Vascular Plant Body: Roots and Shoots Cont’d…
vascular plants have three main non-reproductive organs: the leaf, the stem, and the root
composed of three tissue types: dermal tissue, vascular tissue, and ground tissue

8. Plant Tissues

9. 1. Dermal Tissue Forms the outermost layer of a plant Periderm tissue:
Only on woody plants
Forms bark on stems and large roots
Epidermal tissue:
Thin layer of cells covering the surface of leaves, stems and roots

10. Epidermal Can be specialized
Leaf cells produce a waxy waterproof cuticle
Root hairs to absorb water and minerals

11. 2. Vascular Tissue transportation system Vascular bundle (veins)
Xylem:
Transports water and dissolved minerals from roots to the leaves
Phloem:
Transports a sugar solution from the leaves to the roots

12. 3. Ground Tissue Located between dermal and vascular tissue
Variety of functions:
Photosynthesis
Food and water storage
Structural support

13. 2 main types of Ground tissue
Palisade layer:
main site of photosynthesis, near surface
Spongy mesophyll:
Interior of leaf, photosynthesize, loosely packed

14. The Vascular Plant Body: Roots and Shoots Cont’d…
meristematic cells: unspecialized plant cells that can actively divide and differentiate to form specialized cells (located at the tip of roots and shoots )
lateral meristems cause plants to grow wider and apical meristems cause plants to grow taller
specialized cells that make up plant tissues come from unspecialized cells during cellular differentiation

15. Characteristics of Plants
Learning Goal: To explore the basic needs and make up of plants.
Success Criteria:
I know I am succeeding when I can…
explain the basic conditions plants need in order to survive
describe the specific adaptations that allow plants to survive under various conditions
describe the basic structures common to vascular plants and explain the purpose(s) each structure serves
explain the evolutionary relationships among various plant groups

16. Homework
Answer 12.1 questions #1-4 on page 545