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Lamina - what is?
Is the leaf blade
What is a Petiole
It is the stem a leaf is carried on, may extend along the centre of the leaf forming the Mid-rib
Where does the leaf grow from on the stem
From the NODE on the stem
What is the name of the angle formed by the leaf and the stem
Where are the axillary buds found
in the LEAF AXIL
What are the leaf characteristics (There are 6)
* Leaf Structure * Attachment * Arrangement * Shape * Venation * Margin
Refers to the lamina of the leaf, is it simple or compound
What is leaf attachment
How the leaf joins the stem  
What is arrangement
The distinctive pattern of how the leaf grows on the stem - how the leaves are arranged in relation to eachother
What is the leaf shape?
The smape of the lamina of leaf or leaflets
What is the leaf Venation?
The pattern of the veins on a leaf
What is the leaf Margin?
The edge of the lamina
What makes a compound leaf different from a simple leaf (referring to leaf structure)
A compound leaf has leaflets (multiple parts)
What is a compound leaf called if the leaflets grwo from the continuation of the petiole & what are the leaflets called?
The leaf is called a pinnate The leaflets are called pinnae Ie. Elder (sambucus nigra)
What are pinnules
Pinnae that are divided up into further leaflets
What is a palmate
It is where the pinnae grwo from the end of a petiole ie. trifolium pratense (red clover)
Name 3 standard leaf attachments
Articulate - definate joint can be seen Petiolate - petiole connects the leaf to the stem Sessile - there is no petole and leaves join straight to stem - ie. grasses, clivers
What is sheathing
It is a special leaf attachment - bases of petioles wrap around the stem eg Petrolselinum crispum (parsley)
What is decurrent & perfoliate
Decurrent - where the lamina extends onto the side of the stem ie. Comfrey - Symphytum officinale Perfoliate - Where teh stem appears to grow through the leaf laina (sum gum trees)
What are the 4 types of leaf arrangement
Alternate - only 1 leaf growing on each node  Alternate distichous is when it appears to be growing in a spiral Opposite - 2 leaves opposite from same node Whorled - more than 2 leaves from 1 point Basal/Radical - All grwo fromthe base of the stem Taraxacum officinale - dandeloin
What does penniveined mean?
Small veins run parallel to eachother away from the mid rib on a monocot plant
What does Runcinate, Lyrate & Palmatifid refer to when describing a leaf
The leaf indentation Runcinate - sharp indentations, widest at the apens and tapering towards base Lyrate - as above but with blunt indentations Palmatifid - lamina deeply dissected into finger like projections - ie. maple leaf
Why is the leaf surface coated in cuticle
To prevent excessive water loss
What is stomata
Special openings that can open and clsoe for gas exchage preventing excessing water loss
Name the 3 vestiture on the surface of leaves
Glabrous - smooth surface w/out hairs or other covering Glaucous - bluish waxy surface - eucalypts/mango Pubescent - covering of fine hair
Small leaf like structures found in pairs on the base of the petiole
Membranous sheath found around the nodes of certain plans - formed from fused stipules
What is the leafs function
1/ Photo synthesis 2/ Maintenace of water balance 3/ Gaseous exchange
Photosynthesis - how does it work
The plant processes the suns energy to join carbon, hydrogen and oxygen into sugar molecules
What makes a plant green & why is it needed
Chlorophyll - needed to absorb the light energy
What is the difference between Autotrophs & hereotrophs
Autotrophs - Can make their own food - most plants are autotrophs
What is an example of a bract
Asteracea family - long thin bracts around flower head
What are leaf modifications
Tendrils - wrap around structures Spines - protection for plant Bracts - Grow at base of flower stalks