1. Stem Study Guide Answers

2. Introduction & Diagram Monocot Dicot

3. 2. Functions Support leaves & flowers
Transport water, minerals, & food
Some also store excess food &/or photosynthesize

4. 3. Herbaceous vs. Woody Stems
Herbaceous - soft, green & can
photosynthesize
-examples: petunias, carnations
Woody - hard & rigid with cork &
vascular cambium
-examples: conifers, perennial
dicots

5. 4. Stems & Food Storage
Corms - short, thick underground stem with leaf scales (gladiolus)
Tubers - swollen underground stem with buds (potato)
Rhizomes - horizontal underground stems that store food (iris)

6. 4. Stems & Food Storage

7. 5. Benefit of food storage in stems
Helps plant survive drought or cold and enable it to grow from year to year

8. 6. Herbaceous stem - most abundant tissue
Pith - lightweight space filler

9. 7. Tissue in herbaceous dicots but NOT monocots?
Cambium

10. 8. Herbaceous Monocot vs. Dicot?
Monocots have scattered vascular bundles whereas dicots have bundles arranged in a ring around the cambium

11. 9. Woody Stem Diagram

12. 10. Tree Cross Section & Aging

13. 11. Cause of Annual Rings? Seasonal changes
- springwood has many large vessels
= light rings
-summerwood (late in the season) has
fewer, smaller vessels = dark rings

14. 12. Heartwood vs. Sapwood Heartwood - clogged xylem at center of
woody stem (non-functional)
& darker due to resins,
gums, & tannins
Sapwood - lighter, functional xylem on
outer edges of stem

15. 12. Heartwood vs. Sapwood

16. 13. Bark
Tough, corky tissue that protects the stem from damage by insects & herbivores; also protects against water loss &

17. 14. Bark Tissues Bark is composed of: -cork -cork cambium -cortex
-phloem

18. 15. Phloem
Phloem can transport other substances besides sugar, such as hormones, amino acids, & viruses

19. True or False: Primary growth is growth in diameter.
False; primary growth is growth in length

20. 17. True or False: Buds for new leaves usually grow at the nodes

21. The End