Plant Structure and Function

Chp 5

What are the 3 types of tissues that plants have, what are their function?

1. Dermal:

   • Function: Protective outer covering

   • Examples: Epidermis, periderm

   • Often includes specialized structures like stomata or trichomes

2. Ground:

   • Function: Everything else — photosynthesis, storage, support

   • Made up of 3 simple tissues:

     • Parenchyma 🌿 (versatile, storage, photosynthesis)

     • Collenchyma 💪 (flexible support)

     • Sclerenchyma 🪵 (rigid support)

3. Vascular:

   • Function: Transport of water, nutrients, and sugars

   • Examples:

     • Xylem (transports water and minerals)

     • Phloem (transports sugars)

Plant Structures and Their Functions

Key Structures:

• Roots

• Stems

• Leaves

• Flowers

• Fruits

• Seeds

Key structures:

• Roots – Absorb water and minerals, anchor the plant.

• Stems – Support the plant, transport nutrients and water.

• Leaves – Site of photosynthesis and gas exchange.

• Flowers – Reproduction (contain male and female organs).

• Fruits – Protect seeds and aid in dispersal.

• Seeds – Contain embryo and stored food for germination.

What are the cells viewed in the celery cross section? (pg 78)

• epidermis

• collenchyma

• parenchyma

• phloem

• vascular cambium

• xylem

When using blue dye [Toluidine blue O - TBO], what colour are the stains of primary cell walls vs secondary cell walls?

• Primary Cell Walls: Pinkish Purple

• Secondary Cell Walls: The lignin part is going to Bluish Green

What is the function of Toluidine Blue?

A staining reagent or biological stain that binds to acidic components on plant tissues making plant features visible.

True or False: There are plants who only have primary cell wall and plants who have both primary cell wall and secondary cell wall

True

What are key structural components of a primary cell wall?

• Thin, flexible.

• Found in all plant cells.

• Made of cellulose.

What are key structural components of a primary cell wall?

• Thicker, rigid.

• Found in support cells (e.g., sclerenchyma, xylem vessels).

• Contains lignin.

True or False: Parenchyma and Collenchyma have both primary and secondary cell walls

False, Parenchyma and Collenchyma only have primary cell walls since they are seen to be flexible for first stages of plant growth

True or False: Sclerenchyma and Xylem have both primary and secondary cell wall

True

Collenchyma

Function (what is it for)?

Where is it found?

What do its cells look like?

Is it live at maturity?

• Functions in providing flexible support without restricting growth

• Often found under epidermis and near vascular tissue

• Visually has uneven thickened cell walls, elongated cells, smaller than parenchyma

• Living at maturity

Parenchyma

Function (what is it for)?

Where is it found?

What do its cells look like?

Is it live at maturity?

• Performs most of the metabolic functions for plants;

  • Photosynthesis: Leaves

  • Storage: Starch oils, water and other substances

  • Transport: Assists with movement of nutrients and water between tissues

• Most plants organs (roots, stems, leaves)

• Large with thin flexible walls

• Living at maturity

Sclerenchyma (NOT IN CELERY)

Function (what is it for)?

Where is it found?

What do its cells look like?

Is it live at maturity?

• Dead cells that are able to provide support for the plant

• NOT IN CELERY

• Thick cell walls and contain large amounts of lignin

• Dead at maturity

Phloem

What type of tissue is phloem?

Function (what is it for)?

What do its cells look like and where is it located?

Is it live at maturity?

• Vascular

• Transports sugars downwards throughout the plant

• Appears a small tightly packed cell and found between Cambium and Collenchyma towards the center

• Live at maturity

Cambium

What type of tissue is phloem?

Function (what is it for)?

What do its cells look like and where is it located?

When stained- what colour shows up?

Is it live at maturity?

• Vascular

• Site for secondary growth (only in eudicots)

• Looks like xylem but slightly different and located between phloem and xylem

• Blue green colour

• Live at maturity

Xylem

What type of tissue is phloem?

What is it composed of (not visually seen)?

Function (what is it for)?

What do its cells look like and where is it located?

When stained- what colour shows up?

Is it live at maturity?

• Vascular

• Has tracheids (smaller) and vessels (larger)

• Transport minerals and water upwards

• Located close to center below cambium

• May have secondary walls that appear green/blue

• Dead at maturity

Difference between plan drawing and detailed drawing? (pg83)

Plan drawing:

• Relative amounts of each cell type

• Location of one cell type relative to other cell types

Detailed drawing:

• Relative cell size

• Cell shape

• Cell wall thickness

• 3-4 cells should be drawn

For detailed and plan drawing, what should have its actual size calculated? (Add picture examples)

Plan Drawing:

• The whole picture

• In terms of celery plant - From the collenchyma to Xylem

Detailed Drawing:

• Actual size for one cell in each cell types you draw as they should be relative to one another (????)

How to draw Plan drawing?

How to draw detailed drawing?