Leaves Flashcards
Large, flat and green structures involved in photosynthesis
Leaves
Leaves functions for what? Give two
Photosynthesis and transpiration (exit of water from plant as water vapor)
What are the natures of blade? Describe them
- Simple - with one blade of just one part
2. Compound - with a blade divided into leaflets or pinnae or pinnule
Two types of simple pinante
odd and even pinnate (terminal leaflet / at the tip)
Type of pinnately compound leaf which consists of 2 rachis, where leaves are attached to the secondary rachis
Bipinnate
Type of pinnately compound leaf where the leaves are attached to the tertiary rachis
Tripinnate
Type of leaf where leaflets are attached to the rachis
Pinnately compound
Type of leaf where leaflets are attached at the end of the petiole
Palmately compound
Types of palmately compound leaves
- Bifoliate
- Trifoliate
- Quadra / Tetrafoliate
- Pentafoliate
It is the arrangement of leaves on the stem
Phyllotaxy
Phyllotaxy: one leaf per node
Alternate
Phyllotaxy: two leaves on a node attached oppositely
Opposite
Phyllotaxy: each pair of leaves is perpendicular with one another
Decussate
Phyllotaxy: three or more attached to the node wherein the leaves are equidistant
Whorled
It is the arrangement of veins on the blade of a leaf
Venation
3 types of netted venation
- Pinnately netted - lateral veins arise from the midrib
- Palmately netted - veins arise from one point of the base of the leaf
- Radiately netted - principal veins radiate at the tip of the petiole (center)
4 types of parallel venation
- Parallel to midrib
- Perpendicular to midrib
- Acute angle to midrib
- Palmately parallel
It is a layer of living cells. Trichomes, guard cells, bulliform cells and a cutin layer is present.
Epidermis
Mesophyll is composed of ___?
Parenchyma cells (chlorenchyma and aerenchyma)
Internal structure of a dicot leaf: It is the photosynthetic region of the leaf
Mesophyll
Dorsiventral or bifacial
Horizontal
Isobilateral or equifacial
Vertical
What is the function of bulliform cells?
Prevents water loss
Internal structure of a midrib: the upper part is the ___ and the lower part is the ____ for a crescent shaped leaf
Upper = xylem, lower = phloem
Arrange the internal structure of a midrib
Epidermis > collenchyma > parenchyma > xylem > phloem
Internal structure of a gymnosperm leaf: True or false: the pine needle leaf is evergreen and xeromorphic
True
What does xeromorphic mean?
Can withstand hot environment
The purpose of having a sunken stomata is to ___?
Prevent water loss
Leaf aging due to the breakdown of chlorophyll, sugars, and loss of photosynthetic ability
Senescence
Detachment area of leaves from the stem
Abscission zone
Special leaves: Thick and fleshy, reduced surface-volume ration for water retention
Succulent leaves
Special leaves: For protection
Sclerophyllous foliage
Special leaves: No blade and needle-shaped
Spines
Special leaves: Sensing contact with other objects, no lamina for support
Tendrils
Special leaves: For support and protection
Motile leaves
Special leaves: Digest insects and absorb nitrogen for their amino acid
Insect traps
Special leaves: Product plantlets for asexual reproduction
Adventitious buds
Modified leaves: Aerenchymatous leaf base for buoyancy and support in water hyacinth
Float
Modified leaves: colored leaves are what for?
Attraction
Modified leaves: For support
Supporting leaf bases - pseudotrunk
Modified leaves:
Expanded leaf-like petiole and stipule for photosynthesis
Light harvesting portion of the leaf
Leaf blade / Lamina
Stalk the holds the blade out into the light
Petiole
A leaf with a petiole
Petiolate
A leaf without petiole
Sessile
Extension of petiole
Rachis
Stalk that holds the leaflet
Petiolule
Formed when the base of the leaf is wrapped around the base
Leaf sheath
Tip of the leaf blade
Apex
Midvein, from which the lateral veins emerge
Midrib
Bundle of vascular tissue
Vein
A pair of appendages or outgrowth at the base
Stipule
