1. Comparing Cells from Different Parts of the Plant
Advanced Plant and Soil Science
(c) (14) (a)
specialization of plant structures & functions

2. Basic Parts of the Plant
Roots
Stems
Leaves
Flower

3. Functions of Roots
1. Anchor Plant 2. Absorb water and minerals 3. Translocate water and minerals to stem 4. Store Food

4. Functions of Stems
1. Translocate water, minerals and food to the leaves 2. Support the leaves and display them to light 3. Store Food

5. 1. Make food through photosynthesis 2. Provide site of gas exchange
Functions of Leaves
1. Make food through photosynthesis
2. Provide site of gas exchange
3. Store food

6. 1. Contain organs for specialized sexual production
Functions of Flowers
1. Contain organs for specialized sexual production
2. Produce seeds and fruit

7. Root Types
Primary Roots
Lateral or Secondary Roots
Adventitious Roots
Fibrous Roots
Tap Roots
Storage Roots
Aerial Roots

8. Primary Root Definition: the first root produced by a germinating seed
Arises from the radicle of the seedling, which grows to form lateral roots
Axial Structure
No Nodes and internodes
Limited area near the root tip
No nodes and internodes- no leaves or leaf like structures

9. Lateral or Secondary Roots
Definition: roots that grow horizontally away from the primary root.

10. Adventitious Roots
Definition: Roots developed from the stem that replace the primary root after it dies at an early stage.
These roots are equal in size
Give rise to lateral roots
Develop in places other than nodes
Can form cuttings and rhizomes
Do not undergo secondary growth

11. Fibrous Roots
Definition: root structures in which the primary and lateral roots develop equally so that there is not a definite taproots.
Many finely branched secondary roots
Primary root is short lived
Do not branch profusely, are shallow and spread horizontally cannot provide strong anchorage
Main root system of monocots
Shallow roots cover a large are
More effective absorption of water and minerals
Roots hold the soil to prevent erosion

12. Tap Roots Definition: continuation of the primary root.
Ideal for anchorage
Penetration is greater for water
Storage area for food made by photosynthesis
Bares many branches
Remains underground
Usually found in dicots

14. Storage Roots Definition: structures which are used for food storage.
Swollen portions of primary roots or lateral roots
Usually involves secondary growth in which the secondary xylem or phloem become filled with food reserves

15. Aerial Roots
Definition: short roots that grow horizontally from the stems
Fasten the plant to a support
Function as prop roots or anchorage
More common in tropics

16. What are roots composed of?
Root cap
Apical meristem
Region of elongation
Region of differentiation
Xylem
Phloem
Root hairs

18. Definitions
Root cap: covers the apical meristem and protects it from damage.
Apical meristem: region of active cell division; the growing point of the plant.
Region of elongation: cells here grow longitudinally which causes the root to grow longer.
Region of differentiation: the region of mature primary tissues which is an area of active water and mineral absorption.
Xylem: transports water and nutrients upward.
Phloem: transports carbohydrates and sugars downward.
Root hairs: increase surface area and aid in absorption.

19. Root Hairs
Definition: tiny one celled hair like extensions of the epidermal cells located near the tips of the roots where vascular tissues have formed.
Increase surface area
Absorb water and minerals from soil

20. Specialized Stems Corm Bulb Tuber Crown Spurs Rhizomes Stolon

21. Corm Ex. Gladiolus, crocus Underground Solid, fleshy, scale covered

22. Bulb Ex- tulips, lilies, onions
Layers of fleshy scales that overlap each other
Underground stem
(tulips, lilies, onions)
Layers of fleshy scales that overlap each other
Underground stem

23. Tuber Ex- potato, caladium Food storage area
Short, thick underground stem
(potato, caladium)
Food storage area
Short, thick underground stem

24. Crown Ex- African Violets, fern Closely grouped stems or plantlets
Just above ground or just below
Picture- African violet

25. Spurs Ex- pear and apple trees
Short stems found on woody plant limbs adapted for increased production of fruits

26. Rhizomes Ex- iris, lily of the valley Underground stems
Produce roots on the lower surface and extend leaves and flower shoots above the ground

27. Stolon Ex- strawberry, airplane plant
Stem that grows horizontally above the soil surface

28. Tissues of the Leaf
Epidermis
Mesophyll layer
Veins or vascular layer

30. Epidermis Cuticle Stomata Guard Cells
Waxy substance covers the leaves and stems
Waterproof layer that keeps water in plants
Stomata
Openings in the epidermis
Exchange of gases
Guard Cells
Two cells located on each side of stomata
Open and closes stomata

32. Mesophyll Layer Palisade mesophyll Primary site of photosynthesis
Spongy mesophyll
Contains air and chloroplasts
Site of photosynthesis and gas exchange

33. Veins or vascular bundles
Located in spongy mesophyll
Phloem tissues conduct food from photosynthesis to rest of plant
Xylem tissues conduct water and minerals up to cells in leaves and stems

34. Parts of a Flower Peduncle Receptacle
tip of the stalk where the flower begins
Receptacle
starts at the peduncle and acts as a base to which all other parts of the flower are attached

35. Parts of a Flower Sepals Petals Outer covering of the flower bud
Protects the stamens and pistils when flower is in bud stage
Collectively called calyx
Petals
Inner whorl of leaves
Protects stamen and pistils
Attracts pollinating insects
Known collectively as the corolla

36. Male Reproduction: Flower
Stamen
Male organs
The number per flower varies
Composed of two parts:
Anther- produces pollen
Filament- supports the anther

37. Female Reproduction: Flower
Pistil
Female organs
There can be one or more
Three parts:
Stigma- holds the pollen grains and is sticky
Style- connects the stigma to the ovary
Ovary- enlarged portion at base of pistil and produces ovules which develop into seeds

38. The peduncle is the tip of the stalk where the flower begins
The peduncle is the tip of the stalk where the flower begins. The receptacle starts at the peduncle and acts as a base to which all other parts of the flower are attached.

39. References
Comparison of Root, Stem and Leaf Structure and Function in Dicots. (n.d.). Welcome to Hillfield Strathallan College. Retrieved May 21, 2012, from
Primary Root Structure and Development . (n.d.). EEOB. Retrieved May 21, 2012, from
Root Structure and Function. (n.d.). Botanical Science . Retrieved May 21, 2012, from tructure/RootsStructure.htm
Root System. (n.d.). BIO. Retrieved May 21, 2012, from
The Structure of Plants . (n.d.). The Structure of Plants . Retrieved May 21, 2012, from homepage.smc.edu/hodson_kent/plant_growth/Angiosperms/ID/basics.htm

40. Developed under contract with the Department of Agricultural Leadership, Education & Communications, Texas A&M University for the Texas Education Agency Educational Excellence for AFNR Curriculum Project ©Texas Education Agency, 2014