Home / iGCSE / Coordinated Sciences / B6.2 Leaf structure Paper 2

CIE iGCSE Co-Ordinated Science B6.2 Leaf structure Exam Style Questions Paper 2

CIE iGCSE Co-Ordinated Science Paper 2 - All Chapters

Question

The diagram shows a mesophyll cell.

In which structure does photosynthesis take place?

▶️ Answer/Explanation
Photosynthesis occurs in the chloroplast, the green organelle found in plant cells that contains the pigment chlorophyll, which absorbs light energy.
The overall equation is \(\text{CO}_2 + \text{H}_2\text{O} \xrightarrow{\text{light}} \text{glucose} + \text{O}_2\); all stages (light-dependent and light-independent reactions) take place within the chloroplast.
✅ Answer: (A)

Question

The diagram shows a cross-section through a leaf.

Which tissue is adapted for gas exchange?

▶️ Answer/Explanation
The spongy mesophyll layer contains loosely packed cells with large interconnected air spaces.
These air spaces allow carbon dioxide and oxygen to diffuse easily to and from the mesophyll cells, and out through the stomata.
This makes it the tissue best adapted for gas exchange, labelled D in the diagram.
✅ Answer: (D)

Question

The diagram shows a section of a dicotyledonous leaf.

Which layer is the spongy mesophyll?

▶️ Answer/Explanation
Layer A is the upper epidermis, and layer B shows tall, tightly packed columnar cells — the palisade mesophyll.
Layer C shows loosely packed, irregularly shaped cells with air spaces between them — this is the spongy mesophyll.
Layer D is the lower epidermis.
✅ Answer: (C)

Question

The diagram shows a section through a leaf.

Which labelled part enables oxygen to escape from the leaf?

▶️ Answer/Explanation
Oxygen produced during photosynthesis diffuses out of the leaf through stomata, which are pores surrounded by guard cells. The labelled part that forms these pores allows gas exchange.
✅ Answer: (C) (Stomata/guard cells)

Question

The diagram shows a mesophyll cell.

In which structure does photosynthesis take place?

▶️ Answer/Explanation
Photosynthesis occurs in the chloroplast, the green organelle found in plant cells that contains the pigment chlorophyll, which absorbs light energy.
The overall equation is \(\text{CO}_2 + \text{H}_2\text{O} \xrightarrow{\text{light}} \text{glucose} + \text{O}_2\); all stages (light-dependent and light-independent reactions) take place within the chloroplast.
✅ Answer: (A)

Question

What causes plant leaves to turn yellow?
(A)  a lack of magnesium in the soil
(B)  a lack of starch in the leaves
(C)  a reduction in the rate of photosynthesis
(D)  a reduction in the rate of respiration

▶️Answer/Explanation

Ans :  A

Question

The diagram shows a cross-section of a leaf of a plant.

The leaf is adapted to float on water with the upper epidermis exposed to the air.

                 

Which statement explains one adaptation visible in the diagram?
(A) Guard cells in the lower epidermis are always closed to stop water escaping the leaf.
(B) The palisade mesophyll cells are next to the lower epidermis to maximise photosynthesis.
(C) The stomata are in the upper epidermis so that gas exchange with the air can take place.
(D) There is no cuticle in the upper epidermis to prevent water entering the leaf.

▶️Answer/Explanation

Ans : C 

More CIE iGCSE Co-Ordinated Science Paper 2 Questions..
Scroll to Top