Diagram 3.1 shows a part of cross-section of eudicot root structure.
(a) Complete Diagram 3.1 by drawing and labelling the structure of vascular cylinder. [2 marks]
(b) Root hair cells function to absorb water and minerals.
Explain one adaptation of root hair cells to carry out its function efficiently.
Adaptation : ………………………….
Explanation : ………………………….
[2 marks]
(c) Diagram 3.2 shows plant J growing on a host tree.
(i) State the effect on the growth of the host. [1 mark]
(ii) Plant J is transferred and planted in a rocky and sandy area. The plant is also exposed to the hot sunlight.
Explain why the growth of plant J is slower in the new environment. [2 marks]
Answer:
(a)
1: The shape and position of xylem and phloem for primary growth
2: Correct label of xylem and phloem
(b)
A1: Root hair cells are not covered by a cuticle // thin cell walls // cell membranes that are permeable to water
E1: to speed up water absorption // facilitate water movement
A2: Root hair cells also have large vacuoles
E2: to store water and mineral salts
A3: Has cytoplasmic elongation laterally from the outer wall // large number of cells
E3: To increase the amount of surface area
Any matching pair of A+E
(c)(i)
Growth is not affected / normal
(c)(ii)
1: Soil structure that has a low water supply
2: Less water / nutrients seep into the roots
3: Hot sunlight causes the leaves to melt // chlorophyll is destroyed // transpiration levels are high
4: Photosynthesis levels are reduced
Any two answers
Diagram 4.1 shows two types of tissues involved in plant’s transport system.
(a) Identify tissues K and L. [2 marks]
(b)(i) Tissue K plays a role in giving support to the plant. State one adaptation on tissue K to carry out the function. [1 mark]
(ii) Explain the importance of adaptation stated in 4 (b)(i) in the economic aspect. [2 marks]
(c) Diagram 4.2 shows the conditions of mango fruits P and Q before the ring of bark is removed from the stem of the tree. Diagram 4.3 shows the condition of mango fruits P and Q after the ring of bark is removed. This process affects the vascular tissues of the tree.
Based on Diagram 4.2 and Diagram 4.3, differentiate the conditions between mango P and mango Q after 1 month. [2 marks]
Answer:
(a)
K : Xylem
L : Phloem
(b)(i) Thickened by lignin
(b)(ii)
1. Forms woody tissue
2. Strong and hard
3. To make furniture / building materials
Any suitable example
(c)
1. Mango P is bigger / sweeter compared to mango Q which is smaller / less sweet
2. Mango P receive more sucrose / photosynthesis products than Q mangoes // no phloem tissue to transport sucrose to mango Q