BOT2601
Assignment 1
Semester 2
Unique No: 340605
DUE 22 August 2025
, Assignment 01
Due date: 22 August 2025 @11pm
Unique number for this assignment: 340605
AI-generated answers will Not be marked!
Question 1: Anatomical Differences & Habitats of Leaf Types (15)
1.1 Xeromorphic (xerophytic) leaves
Definition:
Leaves adapted to chronic water deficit (high heat, high light, low humidity, wind).
A. Diagnostic anatomy (what you’d see in a cross-section)
• Cuticle & epidermis: Very thick cuticle; outer walls heavily cutinised; often
multiple epidermal layers or a hypodermis (collenchyma/sclerenchyma) for extra
protection and stiffness.
• Stomata: Hypostomatous (lower surface only) or greatly reduced density;
sunken in crypts or grooves; crypts commonly lined with trichomes (creates a
still, humid boundary layer).
• Mesophyll: Often isobilateral (palisade on both sides) or with 2–3 layers of
palisade to deal with high irradiance; reduced intercellular air spaces to limit
internal water vapour.
• Mechanical tissues: Prominent sclerenchyma caps on vascular bundles;
subepidermal sclereids/fibres to prevent collapse during dehydration.
• Other features: Leaf rolling in grasses via bulliform cells; resin canals/crystal
idioblasts; sometimes water-storage tissue (overlaps with succulence).
B. Functional pay-off (link structure → function)
Assignment 1
Semester 2
Unique No: 340605
DUE 22 August 2025
, Assignment 01
Due date: 22 August 2025 @11pm
Unique number for this assignment: 340605
AI-generated answers will Not be marked!
Question 1: Anatomical Differences & Habitats of Leaf Types (15)
1.1 Xeromorphic (xerophytic) leaves
Definition:
Leaves adapted to chronic water deficit (high heat, high light, low humidity, wind).
A. Diagnostic anatomy (what you’d see in a cross-section)
• Cuticle & epidermis: Very thick cuticle; outer walls heavily cutinised; often
multiple epidermal layers or a hypodermis (collenchyma/sclerenchyma) for extra
protection and stiffness.
• Stomata: Hypostomatous (lower surface only) or greatly reduced density;
sunken in crypts or grooves; crypts commonly lined with trichomes (creates a
still, humid boundary layer).
• Mesophyll: Often isobilateral (palisade on both sides) or with 2–3 layers of
palisade to deal with high irradiance; reduced intercellular air spaces to limit
internal water vapour.
• Mechanical tissues: Prominent sclerenchyma caps on vascular bundles;
subepidermal sclereids/fibres to prevent collapse during dehydration.
• Other features: Leaf rolling in grasses via bulliform cells; resin canals/crystal
idioblasts; sometimes water-storage tissue (overlaps with succulence).
B. Functional pay-off (link structure → function)
