1. The scientific study of plants. (a.k.a, plant biology)
Botany
The scientific study of plants. (a.k.a, plant biology)

2. Areas of Botany Plant Anatomy Plant Physiology Plant Taxonomy
Plant Geography
Plant Ecology
Plant Pylogeny
Plant Genetics
Plant Cell Biology
Economic Botany
Ethnobotany

3. Plant Importance Oxygen production Food & Beverages
95% from only 20 species
Use of plant extracts (e.g., medicines, perfumes, dyes, flavoring, etc…)
Aesthetics & Home gardening
33 million Americans have home gardens

4. Plant Basics 262,000 species of plants
90% of them are flowering plants
Plants are either woody (trees/shrubs) or herbaceous.
Plants are either annuals, biennials, or perennials.

5. What exactly is a plant?

6. Characteristics of Plants
Multi-cellular
Eukaryotic (have nucleus and other membrane-bound organelles)
Sexually & Asexually-reproducing
Have cellulose-rich cell walls
Have chlorophyll & are photosynthetic*
Immobile
*If not photosynthetic, then descended from photosynthetic organisms! (see next slide →)

7. Devilish Dodder—Not Your Typical Plant
Also known as devil’s gut and strangleweed.
Dodder lacks chlorophyll, so it can’t produce it’s own food.
Parasitic plant
Dodder is not rooted in soil.

8. Although plants are unique, they share characteristics with all living organisms …

9. Plants Are Highly Organized
Cells
Tissues
Organs (leaves, roots, etc…)
Organism
Population
Community
Ecosystem

10. Plants Take In & Use Energy
Photosynthesis—conversion of radiant energy into chemical energy stored in sugar (glucose)
Respiration—the release of stored chemical energy for use by the cell

11. Plants Grow & Develop
Growth—an increase in the size/weight of an organism.
Some plants continue to grow throughout life.
Development—includes all changes in an organism from the start of life to death.
Fertilized egg → Embryo (within seed) → seedling → Adult plant

12. Plants Reproduce
Reproduction—the formation of a new individual by sexual or asexual means

13. Plants Respond to Stimuli
Stimuli to which plants respond include:
Direction, Color & Intensity of Light
Temperature
Orientation toward gravity
Etc…
Some plants respond in a dramatic way—Venus fly trap

14. Plant Populations Evolve Over Time
Adaptations—characteristics that enable an organism to better survive in a certain environment.
Physical features (e.g., thick, succulent leaves of cacti)
Behaviors (e.g., dormancy)

15. General Plant Anatomy
The plant body is organized into a root system and a shoot system:
Root system is generally below ground.
Shoot system consists of vertical stems, leaves, flowers, & fruit that contain seeds.

16. Roots Anchor plant Absorb water & nutrients Transport to stem
Some store food
Root hairs increase surface area

17. Shoots a.k.a. stems Support plant Storage of water and food
Turgor pressure against cell wall holds plant up
Storage of water and food
Transport materials
Photosynthesis

18. Leaves Transpiration: evaporation of water through pores in the leaves
Draws water through plant’s vascular system
Absorption of sunlight for photosynthesis

19. Kingdom Plantae
A brief introduction …

20. How do we classify plants?*
There are a variety of ways to classify plants, but one of the most general ways is to group them according to their reproductive strategy:
Spore: simple reproductive cell with hard, outer wall
Seed: embryo, food supply & protective coat
*We will cover this in depth at a later time!

21. Seedless nonvascular plants
Water and nutrients move from high concentration to low (absorbed)
Require a moist environment
Mosses & liverworts

22. Seedless vascular plants
Ferns
Horsetails
Reproduce by spores

23. Seed plants All have vascular tissue Seed structure: Embryo
Cotyledon(s): store food for embryo

24. Gymnosperms Seeds produced in cones Ginkgo
Conifers (pine, fir, spruce)
Most conifers are evergreen

25. Angiosperms Flowering plants Monocots: 1 cotyledon
Dicots: 2 cotyledons
Fruit: ripened ovary of a flower
Flower structure will be covered in lab!
Includes trees, grasses, houseplants

26. Monocots vs. dicots Number of cotyledons Veins in leaves Flower parts1
Usually parallel
Multiples of 3
Dicots 2
Usually netlike/ branched
Multiples of 4 or 5