1. Introduction to Plants
Chapter 23
Introduction to Plants
Section 1: Adaptations of Plants
Section 2: Kinds of Plants
Section 3: Plants in Our Lives
Plant Structure & function

2. The Plant Cell- review Are plants autotrophic or heterotrophic?
Autotrophic (remember, plants are producers and they make their own food via photosynthesis)
Are plants prokaryotic or eukaryotic?
Eukaryotic (remember, eukaryotes have nuclei just like we do and YOU are EUkaryotes)
Are plants multicellular or unicellular?
Multicellular!
Plant cell walls are made of….
Cellulose

3. The Plant Cell: Label!

4. Vocabulary:
Vascular – refers to an internal system of tubes or vessels to transport materials throughout the plant
*basis or first major division of plants into bryophytes (vascular) and tracheophytes (nonvascular); includes:
- xylem – transports water and minerals up from the roots to the shoots
- phloem – transports sugar (food) down from the leaves to the rest of the plant

5. Xylem brings water up from the roots to the shoots

6. Phloem carries sugar (food) down from leaves throughout the plant

7. Adaptations of Plants Establishment of Plants on Land
Section 1
Adaptations of Plants Establishment of Plants on Land
Absorbing Nutrients
To survive on land, plants evolved the ability to absorb mineral nutrients from the soil.
Preventing Water Loss
To survive on land, plants evolved a waxy outer covering called a cuticle, and stomata and guard cells for gas exchange, to prevent their bodies from drying out.
Reproducing on Land
To survive on land, plants use pollen to reproduce without water and transmit male gametes.

8. Adaptations of Plants Vascular Tissue, Seeds, and Flowers
Section 1
Adaptations of Plants Vascular Tissue, Seeds, and Flowers
Advantages of Conducting Tissue
Vascular plants have a system of well-developed tissues that transport water within a plant.
Advantages of Seeds
Seeds protect and nourish a plant’s embryo, disperse the offspring, and delay the growth of the embryo until conditions are favorable.
Advantages of Flowers
Flowers make reproduction more efficient by promoting pollination.

9. Adaptations of Plants Plant Life Cycles
Section 1
Adaptations of Plants Plant Life Cycles
The Vascular-Plant Sporophyte
The sporophytes of vascular plants have a vascular system. Their bodies consist of an aboveground shoot and an underground root.

10. More Vocabulary
Seed- adaptation to terrestrial life composed of a plant embryo, stores food and contains a protective coat
Cone- reproductive structure of gymnosperms; contains pollen in males and ovules in females
Ovulate cone- from a pinetree (female)
Staminate cone- from a pinetree (male)
Flower- reproductive structure of angisperms composed of 4 sets of modified leaves
Fruit- mature ovary of a flower that protects dormant seeds and aids in their dispersal

11. Cotyledons – nonphotosynthetic leaves of an immature plant; provide source of nutrients until plant can produce its own food

12. Kinds of Plants Nonvascular vs. Vascular
Nonvascular plants do not have a system for transporting water and other nutrients within their body
Vascular plants are plants that contain structures with vascular tissue (roots, stems and leaves)
Seedless plants
Seed plants
Gymnosperms and Angiosperms

13. Kinds of Plants Nonvascular Plants
Section 2
Kinds of Plants Nonvascular Plants
Key Features of Nonvascular Plants
Nonvascular plants are small and lack vascular tissue (roots, stems and leaves).
Kinds of Nonvascular Plants.
Mosses, liverworts, and hornworts are nonvascular plants.

14. Bryophytes – nonvascular plants
20 mm
Liverworts
Hornwort
Moss

15. Bryophytes – nonvascular plants - economically important
Ex) sphagnum moss – also called peat or peat moss
Grows in boggy areas called peat bogs; extremely absorbant; used in agriculture/horticulture

16. Kinds of Plants Seedless Vascular Plants
Section 2
Kinds of Plants Seedless Vascular Plants
Key Features of Seedless Vascular Plants
Seedless vascular plants produce spores with thickened walls that prevent them from drying out.
Kinds of Seedless Vascular Plants
Ferns, club mosses, horsetails, and whisk ferns are seedless vascular plants.

17. Tracheophytes – vascular plants
Seedless plants –whiskferns, horsetails, and ferns
Whisk fern horsetail fern

18. Seedless vascular plants – ferns
- reproduce with spores
- diagram shows spores growing in clusters called sori on the back of the fern

19. Seedless vascular plants dominated during the Carboniferous period.

20. Kinds of Plants Gymnosperms
Section 2
Kinds of Plants Gymnosperms
Key Features of Gymnosperms
Gymnosperms are seed plants that produce cones.
Kinds of Gymnosperms
Conifers, cycads, ginkgoes, and gnetophytes are gymnosperms.

21. Tracheophytes – vascular plants
Seed plants
Gymnosperms – have seeds in cones; include: ginkgos, cycads, gnetophytes, and conifers
Cycad
Ginkgo

22. Welwitschia Gnetum Ephedra
Gymnosperms called gnetophytes; only 3 extant species

23. Conifers: top row: Douglas fir, Sequoia, Cypress; bottom row: juniper, Australian pine tree; not shown: yew, spruce, other pines

24. Kinds of Plants Angiosperms
Section 2
Kinds of Plants Angiosperms
Key Features of Angiosperms
Angiosperms are seed plants that produce flowers and fruits.
Kinds of Angiosperms
The angiosperms are classified as either monocots or dicots.

25. Monocots vs. Dicots Dicots: Monocots: Two cotyledon One cotyledon
Veins netlike
Vascular bundles arranged in ring
Taproot usually present
Floral parts in four or five
Ex. Asteraceae (composite), Brassicaceae (mustard), Fabaceae (legume), and Rosaceae (rose),
Monocots:
One cotyledon
Veins parallel
Vascular bundles in complex arrangement
Fibrous root system
Floral parts in multiples of three
Ex. Iridaceae (irises), Liliaceae(lilies) and Poaceae (grass).

26. Subgroups of Angiosperms: Monocots & Dicots

27. Tracheophytes – vascular plants * Seed plants
Angiosperms – flowering plants - have flowers, fruits, and seeds

28. Grasses are flowering plants, too. So are trees.
Grass flowers

29. Flower
pistil

30. Plants in our Lives Plants as Food
Section 3
Plants in our Lives Plants as Food
Fruits and Vegetables
All types of plant parts—roots, stems, leaves, flowers, fruits, and seeds—provide food for humans.
Root Crops
Root crops, such as potatoes, grow underground.
Legumes
Legumes, such as peas, produce protein-rich seeds in long pods.

31. Plants in our Lives Cereals
Section 3
Plants in our Lives Cereals
Wheat
For more than one-third of the world’s population, wheat is the primary source of food.
Corn
Corn is the most widely cultivated crop in the United States.
Rice
For more than half of the people in the world, rice is the main part of every meal.

32. Fruit or Veggie
Humans eat lots of different plant parts. A fruit is the ripened ovary and contains seeds. Therefore, tomatoes, peppers, squash, olives, and cucumbers are fruits, not vegetables.

33. Vegetables – the vegetative parts of the plants that we eat. Includes:
Roots – carrots, turnips,radishes
Stems – celery, bok choi, rhubarb, garlic,
broccoli, onions, potatoes
Leaves – lettuce, cabbage, parsley
Other plant parts that we eat:
Seeds – pinto beans, peas, sunflower seeds,
corn, pepper corns, rice, pecans, coconut
Flowers – anise flowers (licorice), basil;
Good rule of thumb: if you didn’t get it at the store, DON’T EAT IT!

34. Plants in our Lives Nonfood Uses of Plants
Section 3
Plants in our Lives Nonfood Uses of Plants
Wood
Wood is a source of wood pulp used for making paper, lumber used for building materials, and fuel.
Medicines
Many important medicines are currently made from plants or were originally derived from plants.
Fibers
Plant fibers are used to make paper, cloth, and rope. The most important sources of plant fibers are wood and cotton.

35. We don’t just eat plants, we also wear them, build with them, and use them for medicines!

37. Plant Structure & Function
Chapter 25 Pg

38. 6H2O + 6CO2 + sunlight 6O2 + C6H12O6
More Review
Do you remember the equation for photosynthesis
6H2O + 6CO2 + sunlight 6O2 + C6H12O6
Do you remember what organelle photosynthesis takes place in?
The Chloroplast

39. Plant Structure Plants are composed of: Tissue Roots Leaves Stems
Each plant part – tissue, root, stem, leaf - has a specific role in keeping the plant alive through photosynthesis

40. Structure: Tissues- 3 types
Vascular Plant Body
A vascular plant’s body contains three kinds of tissues—dermal tissue, ground tissue, and vascular tissue.
1.Dermal Tissue Dermal tissue covers a plant. A thin layer of epidermis covers nonwoody parts. Several layers of cork cover woody parts.
2.Ground Tissue Ground tissue is specialized for photosynthesis in leaves and for storage and support in stems and roots.

41. Review: Vascular Tissues
3.Vascular Tissues Vascular tissue conducts water, minerals, and organic compounds throughout the plant.
Xylem - contains vessels, which are made up of cells that conduct water only after they lose their cytoplasm. Water flows between cells through pits and perforations in their cell walls.
Carry reactants
Phloem -contains sieve tubes, which are made up of cells that are still living. Substances pass between the cells through pores.
Carry products

42. Plant Structure: Roots
Function- absorption, storage and anchorage
Roots have a central core of vascular tissue that is surrounded by ground tissue and epidermal tissue.
Root hairs on root tips increase the surface area which increases absorption
Remember that Nitrogen Fixation happens in the roots!
(Nitrogen fixation is when nitrogen in the
atmosphere is converted by bacteria into
nitrogen compounds like ammonia,
nitrates and
nitrites)

43. Plant Structure: Leaves
Site of photosynthesis
composed of blade, veins, petiole
There are different layers of leaves (next slide)
simple or compound

44. Leaves Cross Section
- epidermis – adaptation for terrestrial life- covering of leaf
- waxy cuticle - coats upper and lower epidermis
- stomata – site of transpiration

45. Movement of Water :
Transpiration Transpiration, the loss of water from a plant’s leaves, creates a pull that draws water up through xylem from roots to leaves.
Guard Cells and Transpiration Guard cells control water loss by closing a plant’s stomata when water is scarce. Thus, they also regulate the rate of transpiration.

46. Movement of Organic Compounds
Translocation Organic compounds are pushed through the phloem from a source to a sink in a process called translocation.

47. See pg. 559 – Yes, you need to know the layers of leaves

48. Plant structure: Stems
Function: support and transfer
Contain the Xylem and Phloem
Help define plant types (shrubs, vines, trees, etc)

49. Plant Structure and Function
Chapter 25
Plant Structure and Function
Leaves lose water by transpiration.
Leaves produce sugars in photosynthesis.
Sugars are transported downward in the stem.
Sugars are transported into flowers and fruits.
Sugars are transported upward to leaf buds in the spring.
Water enters the xylem of roots and moves upward into the xylem of the stem.
Sugars are transported downward into roots for use or storage.

50. Overview of plants and photosynthesis happenings