Anatomy of the Dorsiventral (Dicotyledonous) Leaf
A vertical section through the lamina of a dorsiventral leaf reveals a highly ordered structure in which form serves function. This quiz tests the three main parts of the leaf — the epidermis, the mesophyll and the vascular system — and the details that distinguish each one.
You will be asked about:
- The adaxial and abaxial epidermis and their conspicuous cuticle
- The unequal distribution of stomata between the two surfaces
- Palisade parenchyma and spongy parenchyma: shape, arrangement and position
- Vascular bundles in the veins and midrib, enclosed by thick-walled bundle sheath cells
Work through each question carefully and read the explanations — they reinforce the chapter’s own terminology and the logic of tissue systems that carries across roots, stems and leaves.
Q1. A vertical section of a dorsiventral leaf through the lamina shows three main parts. Which set correctly names them?
The lesson states that the vertical section of a dorsiventral leaf through the lamina shows three main parts: epidermis, mesophyll and vascular system.
Q2. The upper surface of the dorsiventral leaf is covered by which epidermal layer?
The epidermis covers both surfaces; the upper surface is the adaxial epidermis and the lower surface is the abaxial epidermis.
Q3. Which feature is described as conspicuous on the epidermis of the dorsiventral leaf?
The lesson states that the epidermis covering both the upper and lower surfaces of the leaf has a conspicuous cuticle.
Q4. In a dorsiventral leaf, how are stomata generally distributed between the two epidermal surfaces?
The abaxial epidermis generally bears more stomata than the adaxial epidermis, and the latter may even lack stomata altogether.
Q5. What does the lesson say about stomata on the adaxial epidermis of a dorsiventral leaf?
The lesson notes that the adaxial epidermis may even lack stomata, since the abaxial epidermis generally bears more.
Q6. The tissue lying between the upper and the lower epidermis of the leaf is called:
The tissue between the upper and the lower epidermis is called the mesophyll.
Q7. The mesophyll of the dorsiventral leaf is made up of which tissue type, and what does it contain?
Mesophyll possesses chloroplasts and carries out photosynthesis; it is made up of parenchyma.
Q8. Which two types of cells make up the mesophyll of a dorsiventral leaf?
The mesophyll has two types of cells — the palisade parenchyma and the spongy parenchyma.
Q9. Which description correctly matches the palisade parenchyma?
The adaxially placed palisade parenchyma is made up of elongated cells arranged vertically and parallel to each other.
Q10. Where is the palisade parenchyma positioned in the dorsiventral leaf?
The palisade parenchyma is adaxially placed, that is, towards the upper surface of the leaf.
Q11. Which statement best describes the spongy parenchyma?
The oval or round and loosely arranged spongy parenchyma is situated below the palisade cells and extends to the lower epidermis.
Q12. What lies between the loosely arranged spongy parenchyma cells?
The lesson states that there are numerous large spaces and air cavities between the spongy parenchyma cells.
Q13. Where can the vascular bundles of the dorsiventral leaf be seen?
The vascular system includes vascular bundles, which can be seen in the veins and the midrib.
Q14. According to the lesson, what determines the size of the vascular bundles in the leaf?
The size of the vascular bundles is dependent on the size of the veins, and the veins vary in thickness in the reticulate venation of dicot leaves.
Q15. What surrounds each vascular bundle in the dorsiventral leaf?
The vascular bundles are surrounded by a layer of thick-walled bundle sheath cells.