Basic Tissues - Plants

Question 1

What are the basic plant tissues?

Answer 1

Dermal tissue (epithelial)
Vascular tissue
Ground tissue
Meristematic tissue

Question 2

What are the functions and locations of dermal tissue?

Answer 2

Functions:

• protect the plant tissues
• prevents water loss

Locations:

• outer layer of stems, roots and leaves
• 1 inner layer in roots

Question 3

What are the functions and locations of vascular tissue?

Answer 3

Functions:

• xylem transports water
• phloem transports water

Locations:
-stems, leaves, roots

Question 4

What are the functions and locations of ground tissue?

Answer 4

Functions:
-makes up bulk of plant mass (parenchyma, sclerenchyma, collenchyma)

Locations:
-Stems, roots, leaves

Question 5

What are the functions and locations of meristematic tissue.

Answer 5

Functions:
-cell division to produce new growth

Locations:

• tips of shoots, roots
• in buds
• around stem of woody plants

Question 6

What is the importance of the epidermis?

Answer 6

• Thick cell walls tightly pressed together = complete cellular layer
• can give rise to guard cells around stomata trichomes (hair cells)

Question 7

What is the importance of the cuticle ?

Answer 7

• covers the epidermis
• acts as transpiration barrier a.k.a helps waterproofing
• interacts with microorganisms e.g. soil bac and fungi = important to root water capture

Question 8

What is the importance of the parenchyma?

Answer 8

Parenchyma – versatile cell type
Thin cell walls
Large vacuoles
Photosynthetic cells in leaves and stems
(chlorenchyma: parenchyma containing chloroplasts)
The only dividing cells (so found in meristems)
+ used in wound repair
Storage cells in roots, stems, seeds (starch)
May be air filled tissue in floating plants

Question 9

What is the importance of the collenchyma?

Answer 9

Collenchyma:
-structural support, growing shoots & leaves
-Living cells, thickened cell walls – thickness depends on
mechanical stress on the plant – may be doubled
eg tough strands in celery sticks!
-Beneath epidermis of stems & leaves
-4 different types, relating to exactly how cells interact with one
another and how the walls are thickened.

Question 10

What is the importance of the sclerenchyma?

Answer 10

Sclerenchyma: main structural support for a plant

• Long, slender cells bundled together
• Thick cell walls; cells themselves are dead
• Develop in association with xylem & phloem, from cambium
• commercially important: used for fibres in fabrics e.g. cotton

Question 11

What is structure of the xylem?

Answer 11

• columns of elongate dead cells thick woody cell walls,
• forming tubes
• tracheids (elongated cells) and vessel elements

Question 12

What are the functions of the xylem?

Answer 12

• water transport
• transpiration
• root pressure
• capillary action

Question 13

What is the structure of the phloem?

Answer 13

-made of cells linked end to end: sieve tubes
-Highly specialised, have lost most of their internal structures
that might slow fluid movement.
-Cells linked end to end via specialised plasmodesmata

Question 14

what are the functions of the phloem?

Answer 14

-transport organic nutrients, mostly sucrose

Question 15

Describe the importance of the meristem

Answer 15

-Sites of growth
-Undifferentiated parenchymal cells; similar to animal
stem cells in roles
-Generate new cells which can then differentiate into new
cell types as the developing structure matures

-Apical for growth of roots and shoots, modified to form flowers
-Primary: increase in length/height, derived from apical
-Secondary: vascular cambium, makes new xylem & phloem
throughout life - wood formation