1. Roots, Stems, and Leaves

2. Life before reproduction
Reproduction is essential to a species’ success
Plants have to grow to the point that they are mature enough, and healthy enough, to reproduce.
Roots, stems, and leaves are the workhorse structures of plants.

3. Roots Obtain water and dissolved nutrients from soil and mycorrhyzae
Anchor plant
Are point of contact for mycorrhizal fungi

4. Types of roots Primary root - from embryo
Aerial root
Primary root - from embryo
Secondary roots –from primary root
Adventitious roots –from leaf nodes
May be modified for support or defense or …
Adventitous roots

5. Root structures Tap roots – from primary root
Fibrous roots – from adventitious or secondary roots
Tuberous roots – thickened ROOTS
Tubers are thickened stems
Tuberous
root
Stem, not root

6. Rhizomes: underground stems, not roots
Rhizomes have nodes and reduced leaves
Rhizomes often root at nodes
Rhizomes enable a plant to spread and reproduce
Rhizomes are most common in mesic and wet habitats

7. Stems Hold up above ground parts of plant; transmit signals
Prickles
Hold up above ground parts of plant; transmit signals
Have leaves and may have branches
Woody or herbaceous
Leaves and branches may be
Opposite
Alternate
Whorled (Verticillate)
May have hairs, prickles, thorns, spines
Alternate
Spines

8. Caudex (pl.: caudices)
Woody stem that does not or only scarcely extends above ground

9. Woody stems also have … Lenticels Leaf scars Bark

10. Leaves – absolutely vital
Evaporation surface (essential to nutrient transport)
Energy converters
Absorb sunlight
Take in CO2 from air
Release O2 as by-product
Food and shelter for others

11. Leaf structure
Simple
Lobed, Divided, pinnatifid, palmatifid, pedate, cleft, parted

12. Compound
Palmately
Pinnately
Odd pin
Even pinnate

13. Flat, revolute, involute

14. Leaf margins Entire, Crenate, Dentate, Serrate Crispate or undulate
Crenate margins
Leaf margins
Serrate margins
Entire, Crenate, Dentate, Serrate
Crispate or undulate
Spinose
Dentate margins
Crisped leaf
Undulate leaves
Spinose leaf

15. Leaf apices

16. Leaf bases and attachment