Function Of Specialised Plant Cells (C2)

Question 1

Meristematic cells

Answer 1

• retain the ability to divide by mitosis to produce new cells
• apical shoot and root meristems produce new cells for growth of shoot and root
• vascular cambium -> increase diameter of stems and roots during secondary growth
• cork cambium produces cork layer -> reduces evaporation of water frm plants and protect against entry of pathogens
• intercalary meristem -> allow growth and increase in length in regions other than the tip

Question 2

Parenchyma tissue

Answer 2

• form the major component of ground tissue of stems and roots expecially in herbaeous plants.
• provide support to herbaceous plants
• help carry out photosynthesis
• store food
• can form secondary meristematic (vascular cambium & cork cambium)
• contain chromoplast to attract pollinating agents and help in the dispersal of fruits and seeds
• can be modified or differentiate to form specialised cells to carry out specific functions

Question 3

epidermis

Answer 3

protective layerto protect inner tissues. The waxy cuticle reduces water loss by evaporation

Question 4

Palisade mesophyll

Answer 4

Contain many chloroplast to carry out photosynthesis

Question 5

Spongy mesophyll

Answer 5

Loosely packed with many large intercellular spaces for gaseous exchange. Contain fewer chloroplast than palisade mesophyll cells to carry out photosynthesis.

Question 6

Endodermis

Answer 6

Forms a selective barrier between the outer cortex and the inner pericycle tissues.

Question 7

Pericycle

Answer 7

Divide to produce the lateral roots and is involved in the secondary growth of roots

Question 8

Aerenchyma

Answer 8

Large air spaces provide buoyancy to the hydrophytes and permit gaseous exchange in the submerged parts.

Question 9

Collenchyma tissues

Answer 9

• Provide herbaceous plants with mechanical strength and flexibility
• some contains chloroplast which can carry out photosynthesis

Question 10

Sclerenchyma fibre

Answer 10

• acts as supporting tissue
• tapered ends of the sclerenchyma fibre overlap and interlock with one another, further increasing their combined strength.

Question 11

Sclereids

Answer 11

-protective tissues which gives strength and support to the plant structures or organs

Question 12

Xylem vessels

Answer 12

• Transport water and mineral ions from the root to the aerial parts of the plants
• to give mechanical support to the plants.

Question 13

Tracheids

Answer 13

Same function as xylem vessels but less efficient