10 questions ยท Form 5 Biology Bab 1: Organisation of Plant Tissues and Growth
What is the primary function of guard cells located in leaf epidermal tissue?
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. What is the primary function of guard cells located in leaf epidermal tissue?
Answer: B
Guard cells are specialized epidermal cells that alter their turgidity to open or close stomata, controlling gas exchange and water loss.
2. During secondary growth in eudicot stems, what tissue is produced toward the INSIDE of the vascular cambium?
Answer: C
The vascular cambium divides inward to produce secondary xylem (wood) and outward to produce secondary phloem.
3. A biannual plant is in its second year of growth. What main physiological process dominates this phase?
Answer: C
In biannual plants, year 1 is dedicated to vegetative growth, while year 2 focuses on reproductive development (flowering and seed production).
4. What structural modification allows root hair cells to maximize water absorption from soil?
Answer: B
Root hairs are specialized epidermal extensions that drastically increase the surface area available for water and mineral ion uptake.
5. What waterproof substance is deposited in cork cells during secondary growth to form bark?
Answer: C
Cork cells formed by the cork cambium accumulate suberin, a waxy waterproof compound that protects inner stem tissues.
6. Where are apical meristems specifically located in a plant?
Answer: C
Apical meristems are located at root tips and shoot apexes, facilitating primary growth (length extension).
7. In the sigmoid growth curve, what phase is characterized by a rapid increase in cell division and expansion rate?
Answer: C
The exponential (log) phase represents the period of most rapid growth where cell division and elongation occur at maximum speed.
8. Which meristematic tissue is directly responsible for increasing the girth (diameter) of woody stems?
Answer: B
Lateral meristems (vascular cambium and cork cambium) drive secondary growth, expanding the stem's girth.
9. Which tissue consists of living cells with unevenly thickened primary cell walls containing pectin and cellulose?
Answer: B
Collenchyma tissue features unevenly thickened walls reinforced with cellulose and pectin to provide flexible mechanical support to young plants.
10. What causes the epidermis of a woody stem to rupture during secondary growth?
Answer: B
The continuous inward formation of secondary xylem exerts outward pressure, stretching and eventually rupturing the primary dermal epidermis.