Angiosperm Morphology: Substomatal Chambers in Ligustrum
cross section: Ligustrum leaf
magnification:400x
Berkshire Community College Bioscience Image Library
These dicotyledonous mesophytes show structural adaptations that extend their tolerance to drought and desiccation.
The uniseriate upper and lower epidermis are heavily cutinized. Stomata are almost entirely limited to the lower or abaxial surface and are enclosed within small chambers partially roofed by ledges of cutin. Numerous mushroom shaped peltate trichomes are present in the lower, and occasionally upper, epidermis. These secretory trichomes have short stalks, appearing to sink into the epidermis.
The upper palisade mesophyll is composed of two compact layers of elongated photosynthetic parenchyma. A well developed lower spongy mesophyll is composed of loosely arranged photosynthetic parenchyma with abundant air spaces. The abaxial stomata open into large irregularly shaped substomatal chambers.
Midrib and blade vascular bundles are collateral with large thick-walled xylem vessels towards the adaxial surface and smaller sieve tubes and companion cells of phloem towards the abaxial leaf surface. Small masses of abaxial sclerenchyma and subepidermal collenchyma are particularly well developed below the midrib vein.
A largely parenchymatous ring of bundle sheath cells is visible around all vascular bundles.
Technical Questions:bioimagesoer@gmail.com
Angiosperm Morphology: Substomatal Chambers in Ligustrum
cross section: Ligustrum leaf
magnification:400x
Berkshire Community College Bioscience Image Library
These dicotyledonous mesophytes show structural adaptations that extend their tolerance to drought and desiccation.
The uniseriate upper and lower epidermis are heavily cutinized. Stomata are almost entirely limited to the lower or abaxial surface and are enclosed within small chambers partially roofed by ledges of cutin. Numerous mushroom shaped peltate trichomes are present in the lower, and occasionally upper, epidermis. These secretory trichomes have short stalks, appearing to sink into the epidermis.
The upper palisade mesophyll is composed of two compact layers of elongated photosynthetic parenchyma. A well developed lower spongy mesophyll is composed of loosely arranged photosynthetic parenchyma with abundant air spaces. The abaxial stomata open into large irregularly shaped substomatal chambers.
Midrib and blade vascular bundles are collateral with large thick-walled xylem vessels towards the adaxial surface and smaller sieve tubes and companion cells of phloem towards the abaxial leaf surface. Small masses of abaxial sclerenchyma and subepidermal collenchyma are particularly well developed below the midrib vein.
A largely parenchymatous ring of bundle sheath cells is visible around all vascular bundles.
Technical Questions:bioimagesoer@gmail.com