1. Parts of Plants and their Functions

2. Objectives Note contributions of plants to the life cycle on earth
List and describe the purpose of the four main parts of plants
Explain process of photosynthesis
Explain process of respiration
Explain major structural differences between dicot and monocot stems
Describe process of pollination

3. Importance of Plants Without plants, life on earth would not exist
Plants are the source of food for humans and animals, directly or indirectly
Plants produce oxygen and are the major producers
Plants help keep us cool, renew the air, slow wind, hold soil in place, shelter wildlife, beautify space, perfume the air, furnish building materials, and fuel

4. ROOTS

5. Root Functions Anchor the plant and hold upright
Absorb water and minerals from the soil and conduct them to the stem
Store large quantities of plant food
Propagate or reproduce some plants
The first three are essential to all plants

6. Root Structure The internal structure of a root is similar to a stem
Older roots of shrubs and trees have a phloem on the outside, a cambium layer, and xylem (wood) on the inside
A phloem is the old outer layers of corklike bark

7. The phloem carries manufactured food down to the root for food and storage
The xylem carries water and minerals up to the stem

8. External structures of roots are different form stems
Roots have a root cap that produce new cells which lubricate a path and protect the cap as new roots push its way through the soil

9. Behind the root cap are many root hairs which absorb moisture and minerals for larger roots and the stem
Side roots of increasing size form as the plant grows older

10. Roots are important agricultural cash crops
Carrots, beets, radishes and sweet potatoes are roots
Roots also serve for propagation
Dahlia, peony, and sweet potato have tuberous root clumps that can be separated will sprout new roots and plants

11. Fibrous Roots Fibrous root plants are very easy to transplant
Roots are smaller, shorter and more compact, allowing more roots to be saved

12. Tap Roots Tap root systems have longer and fewer roots
Tap roots are usually cut off during transplanting which loses root hairs and the ability absorb water and nutrients
Tap roots will conduct and store water and nutrients but not absorb it

13. Roots will move toward moisture in the soil
Central roots grow downward because of the force of gravity
This is know as geotropism and is controlled by the root tip

15. Types of Stems Herbaceous – soft tissue that bends (ex: houseplants)
Woody – brittle, non-bendable, bark-like tissue (ex: trees, shrubs)

16. Functions of Stems Consists of xylem and phloem tissue
Transport materials up and down the plant through the vascular system
Consists of xylem and phloem tissue
Herbaceous stems have vascular bundles, which consist of both xylem and phloem
Woody stems have a vascular cylinder in which the outer portion is the phloem and the inner portion is the xylem

17. Herbaceous Stem
Woody Stem

18. Xylem Tissue Phloem Tissue
Moves water and nutrients UPward from the roots to the stems and leaves
Phloem Tissue
Moves water and nutrients DOWNward from the stems and leaves to the roots

19. Other Functions of Stems
Provide physical support for leaves, flowers, and fruit
Store food (ex: onions, garlic, potatoes)
Green stems have chlorophyll in them and conduct minor photosynthesis
Capable of reproduction
Help establish tendrils which aid climbing plants

21. Underground stem that grows horizontally
Ex: Iris, Ginger
Enlarged stem that grows underground
Ex: Potato
Threadlike leafless growth on a stem that attaches itself to other stems/objects
Ex: Sweet pea
Above ground stem that grows horizontally
Ex: Strawberry
Underground food storage consisting of flat, fleshy leaves with roots on lower side
Ex: Onion
Food storage structure at the end of a stem that grows underground
Ex: Gladiolus

22. Leaves

23. The Plant Body: Leaves FUNCTION OF LEAVES
Leaves are the solar energy and CO2 collectors of plants.
In some plants, leaves have become adapted for specialized functions.

24. EXTERNAL ANATOMY
Leaves possess a blade or lamina, an edge called the margin of the leaf, the veins (vascular bundles), a petiole, and two appendages at the base of the petiole called the stipules.

25. EXTERNAL ANATOMY

26. Phyllotaxy - Arrangement of leaves on a stem

27. Leaf types - Simple, compound, peltate and perfoliate
Simple leaf = undivided blade with a single axillary bud at the base of its petiole.
Peltate leaves = petioles that are attached to the middle of the blade; examples include mayapple
Perfoliate leaves = sessile leaves that surround and are pierced by stems; examples include yellow-wort and thoroughwort
Yellow Wort
Mayapple

28. Leaf types – Pinnately & Palmately Compound Leaves
Compound leaf = blade divided into leaflets, leaflets lack an axillary bud but each compound leaf has a single bud at the base of its petiole
pinnately-compound leaves: leaflets in pairs and attached along a central rachis; examples include ash, walnut, pecan, and rose.
palmately-compound leaves: leaflets attached at the same point at the end of the petiole; examples of plants with this leaf type include buckeye, horse chestnut, and shamrock.

29. Venation = arrangement of veins in a leaf
Netted-venation = one or a few prominent midveins from which smaller minor veins branch into a meshed network; common to dicots and some nonflowering plants.
Pinnately-veined leaves = main vein called midrib with secondary veins branching from it (e.g., elm).
Palmately-veined leaves = veins radiate out of base of blade (e.g., maple).
Parallel venation = characteristics of many monocots (e.g., grasses, cereal grains); veins are parallel to one another.
Dichotomous venation = no midrib or large veins; rather individual veins have a tendency to fork evenly from the base of the the blade to the opposite margin, creating a fan-shaped leaf (e.g., Gingko).  

30. Venation Types
Netted or Reticulate Venation

31. Leaf – Internal Anatomy

32. Specialized or Modified Leaves
Cotyledons: embryonic or "seed" leaves. First leaves produced by a germinating seed, often contain a store of food to help the seedling become established.
Tendrils - blade of leaves or leaflets are reduced in size, allows plant to cling to other objects (e.g., sweet pea and garden peas.
Shade leaves = thinner, fewer hairs, larger to compensate for less light; often found in plants living in shaded areas.
Drought-resistant leaves = thick, sunken stomata, often reduced in size
In American cacti and African euphorbs, leaves are often reduced such that they serve as spine to discourage herbivory and reduce water loss; stems serve as the primary organ of photosynthesis.
In pine trees, the leaves are adapted to living in a dry environment too. Water is locked up as ice during significant portions of the year and therefore not available to the plant; pine leaves possess sunken stomata, thick cuticles, needle-like leaves, and a hypodermis, which is an extra cells just underneath the epidermis

33. Specialized or Modified Leaves
Prickles and thorns: epidermal outgrowths on stems and leaves (e.g., holly, rose, and raspberries; Hypodermic trichomes on stinging nettles.
Storage leaves succulent leaves retain water in large vacuoles.
Reproductive leaves, (e.g., Kalanchöe plantlets arise on margins of leaves.
Insect-trapping leaves: For example: pitcher plants, sundews, venus flytraps, and bladderworts have modified leaves for capturing insects; All these plants live under nutrient-poor conditions and digest insect bodies to obtain nitrogen and other essential nutrients.
Bracts:  petal-like leaves.
Window Leaves:  plant is buried in soil with transparent part exposed to light.  Being buried reduces loss of war in arid environments.
Flower pot leaves:  Structure to catch water and debris for nutrient collection - fairy-elephant's feet.

34. Cotyledons or “seed leaves”

35. Tendrils
Garden Pea

36. Leaves as Needles and Spines

37. Leaves as Colorful Bracts

38. Flower Pot Leaves
Fairy Elephant’s Foot

39. FLOWERS

40. Important Parts of a Flower
4 main parts
Sepal
Petal
Pistil (or carpel)
Stamen

41. Sepals Protect flower while developing from bud
Look like green little leaves
Collectively called CALYX

42. Petals Member of COROLLA All the petals make the corolla
Brightly colored part of a flower
Corolla and calyx make up perianth
Used to attract pollinators

43. Female Parts: PISTIL Sits on the receptacle Made of 4 parts: Stigma
Style
Ovary
Ovule

45. Female Parts Continued
Stigma
Where pollen grains attach to
Style
Long filament structure
Prevents pollen contamination
Ovary
Protects ovule; becomes fruit when fertilized
Ovule
Becomes seed when fertilized

46. Male Parts: STAMEN
3 parts
Anthers
Connective
Filament

47. STAMEN cont… Anthers Filament Produce pollen
Contains thousands of pollen grains
Pollen contains male sex cells
Filament
Holds the anthers
Fine and hair like

49. Other Flower Parts Receptacle Peduncle (pedicel) The part of the
flower that holds
everything
together
Peduncle (pedicel)
Stalk of the flower

50. Types of Flowers
Imperfect
Perfect
Complete
Incomplete

51. Perfect Flower Has both Pistil (Female) and Stamen (Male) Examples:
Lilies, Roses, dandelions, wheat, apple, tomato

52. Imperfect flower Has ONLY one type of reproductive organs
STAMEN OR PISTILS
Requires 2 flowers (1 male, 1 female) to reproduce
Examples:
Corn
Cucurbit family
Melons, gourds, cucurbits (cucumbers)

53. Male vs. Female Corn

54. Male vs. Female Cucurbit

55. Complete Flower Has all 4 parts All complete flowers are
Sepals, petals, pistil, stamen
All complete flowers are
perfect, but not all perfect
flowers are complete.
Why???

56. Complete Flower
Examples:
Roses, zinnia

57. Incomplete Flower Lacks one or more of the 4 parts Examples:
Cucurbitaceae family
Melons, gourds, cucurbits (cucumbers)
Calla lily

58. Monoecious 2 options: Examples: Plant has perfect flowers (both sexes)
Plant has separate male and female flowers located on the same plant
Examples:
Easter Lily, pea, dandelion, rose

59. Dioecious Has imperfect flowers on separate plants
One plant is male, one plant is female
Need 2 plants to reproduce
Examples:
Cucurbitaceae family

60. Monocot Embryo growth with single cotyledon
Flower parts in multiples of 3
Major leaf veins run parallel
Stem vascular bundles scattered
Roots are adventitious
Secondary growth absent
Pollen with single pore

61. Dicot Embryo growth with 2 cotyledons Pollen with 3 pores
Flower parts with multiples of 4 or 5
Stem vascular bundles in a ring
Roots develop from radicle
Secondary growth present
Major leaf veins are netted