1. Chapter 4
4.1 - Plant Systems

2. Learning Goal
To learn more about the components of plant cells, their systems and organization of tissues

3. Introduction
Almost everything we do everyday is achieved through the existence of plants
Plants provide us with food, clothing, shelter, medicine, and most importantly fresh oxygen to breathe with

4. Introduction
Like animals, plants are made up of specialized cells that are organized into tissues that are then organized into systems of organs
There are many parts, roles, and functions of plant tissues that work within these systems that allow plants to survive

5. Understanding Plant Systems
Let’s take a look at what we already know ….

6. cannot move from place to place
SYSTEMS IN PLANTS
Plants:
usually green
cannot move from place to place

7. SYSTEMS IN PLANTS Flowering plants have 2 main “body systems”:
1) “root”
2) “shoot”

8. SYSTEMS IN PLANTS

17. internal nutrient transport reproduction
SYSTEMS IN PLANTS
Plant body systems functions:
gas exchange
internal nutrient transport
reproduction

18. SYSTEMS IN PLANTS - usually underground - anchors the plant
1) Root system:
- usually underground
- anchors the plant
- absorbs water/minerals from soil
- stores food

19. Types of Root Systems There are 2 main types of roots: Taproot
Fibrous Roots
Made of THICK root system with smaller lateral branching roots
Anchors plants
Absorb water and minerals
Stores food and water below ground level
Ex- Carrots , dandelions
Made up of smaller branching roots
Roots are about the same size that grow from a central point
Don’t grow as deep as taproots
Ex – grass roots, scallions

20. Types of Root Systems

21. Roots
Root system is usually the 1st structure to grow from a seed when it sprouts
Roots have 3 Main Functions:
Take in water and dissolve minerals that are transported to where needed in the rest of the plant
Anchor the plant in the soil to support the plant against forces like wind and water
Store the carbohydrates that are produced by photosynthesis in the leaves or green stems, as well as water and other nutrients

22. Root Structure and Function
The tip of the root is covered by the Root Cap
The Root Cap is made up of parenchyma cells
[puh-reng-kuh-muh] 
that help protect the growing tissues as the root extends through soil or more resistant materials, like rocks

23. SYSTEMS IN PLANTS
2) Shoot system:
- leaf
- flower
- stem

24. - contains chloroplasts - site of photosynthesis
SYSTEMS IN PLANTS
2a) Leaf:
- contains chloroplasts
- site of photosynthesis
light energy + carbon dioxide + water glucose + oxygen
chlorophyll

25. Leaf Structure and Function
Regardless of the different shape or size of leaves, they all have the same function: to convert light energy from the Sun into chemical energy for food via photosynthesis

26. Leaf Structure and Function
The external structure of a typical leaf has a flat portion called the blade
The blade and the stem can attach directly or indirectly through a structure called a petiole
The epidermal cells of leaves release a waxy substance that forms the cuticle
Acts as a protective layer that keeps water in and reduce evaporation
Vascular tissue runs through the petiole, connecting the leaf, veins, and stem to transport vital nutrients throughout

27. Internal Structure of a Leaf

28. Internal Structure of a Leaf
The cuticle and the epidermis of a leaf are transparent, which lets light through it
Between the upper and lower epidermis of a leaf is the mesophyll
Right below the upper epidermis is a row of tightly packed cells celled the palisade mesophyll cells
They contain lots of chloroplast, which is why most photosynthesis takes place here

29. Internal Structure of a Leaf
Below the palisade mesophyll is the spongy mesophyll
The cells located here are irregular in shape and loosely packed to allow for gas exchange to take place, where:
Reactants CO2 + H2O move in
Waste Product O2 moves out

30. 2b) Flowers: SYSTEMS IN PLANTS
- contain male or female reproductive structures
- male structures produce pollen
- female structures produce eggs
- after fertilization, seeds form within a fruit

31. SYSTEMS IN PLANTS Flowers can be made up of male & female parts
The Female part called the pistil.
The Male part is called the stamen 

32. - supports leaves & flowers - transports materials
SYSTEMS IN PLANTS
2c) Stem:
- supports leaves & flowers
- transports materials

33. Stems
There many different types of stems, who’s function is to provide support for the plant’s leaves and reproductive structures
Based on various adaptations, stems can be soft and flexible or hard and wood like in order to help plants survive

34. Stems
Stems are used to store excess food, while others help the plant withstand drought, cold, or heat
A plant’s stem has 2 MAIN FUNCTIONS
Physical Support
Transportation of water, nutrients and sugars

35. Cross – Section of a Stem

36. Cross – Section of a Stem

37. Stems – Xylem Stems contain most of a plant’s xylem tissue
As xylem cells grow, they form long, straw like tubes or vessels that eventually turn into “pipes” in the plant tissue that allow water to flow through
Xylem are hollow, which helps things pass through it

38. Stems – Xylem

39. Stems – Phloem Phloem tissue is also made of vertically stacked tubes
Their cell walls are porous (have holes), which lets materials move between cells and neighboring plants

40. SYSTEMS IN PLANTS - food - fibres - flavourings - medicines
Uses of plant tissues:
- food
- fibres
- flavourings
- medicines

41. A closer look at Plant Tissues

42. Specialized Cells in Plant Tissues
A healthy plant is always growing and making new specialized cells
Groups of specialized cells form tissues, and groups of tissues work together in organs, such as roots, stems, and leaves
Each plant organ performs critical tasks for a plant’s survival
This growth take place because of special plant cells called Meristematic cells or Meristems
These cells behave similarly to stem cells in humans, in that they are “undifferentiated” – meaning they can be almost anything the organism needs

44. Plant Tissues – 4 Main Types
Meristematic Tissue
Consists of undifferentiated embryonic plant tissue where other all plant tissues develop from through Mitosis
Are located in the following places
near tips of roots and stems (called apical meristems)
in the buds and nodes of stems.
in the cambium between the xylem and phloem in dicotyledonous trees and shrubs.
under the epidermis of dicotyledonous trees and shrubs (cork cambium)
in the pericycle of roots, producing branch roots.

45. Plant Tissues – 4 Main Types
Dermal Tissue
Is the outer covering of the plant that forms a protective covering; including the Epidermis & Periderm

46. Plant Tissues – 4 Main Types
2. Specialized Epidermal Tissues
Name of Tissue
Function
Guard Cells
Found in the plant cell epidermis that regulate the opening and closing of the stomata
Stomata – a small opening pores in the leaf that lets gas exchange (CO2 / O2) to occur
Trichomes
Extensions of epidermal cells found on stems, and leaves of plants to help reduce water loss
Make the plant look “fuzzy”
Root Hairs
Fine hair-like structures that cover the surface of the root of the plant
Increase surface area for Gas Exchange

47. Plant Tissues – 4 Main Types
Ground Tissue
Makes up most of the plant’s internal and external materials
Contains parenchyma cells, collenchyma cells, and sclerenchyma cells
Functions include photosynthesis, storage
Also provide support for the plant when it grows other types of tissue

48. Plant Tissues – 4 Main Types
Vascular Tissue
Is the internal system of tubes that run vertical throughout the stem of the plant, connecting the roots and leaves
Main function is to TRANSPORT water and nutrients throughout the plant
There are 2 types of vascular tissue
Xylem – transports water and minerals FROM the roots to the leaves
Phloem – transports nutrients like sugar to where needed for metabolism and storage
Lab:

49. Plant Tissues – 4 Main Types
(Resource)

50. Plant Tissues – Summary
Cell Types
Function
Locations
Meristematic
tissue
Parenchyma
Divide to produce new growth
Tips of shoots
Tips of roots
In buds
In a ring around the stem in woody plants
Dermal
Protect plant tissues and prevent water loss
Outer layer of stems, roots, and leaves
Ground
Parenchyma Collenchyma Sclerenchyma
Makes up bulk of plant mass
Stems, roots, leaves
Vascular
Xylem is made up of vessels and tracheids
Phloem is made up of sieve cells and companion cells
Xylem transports water
Phloem transports sugars
In stems, leaves, and roots