This document is a presentation on leaf structure and function by Halala Rahman Qadir. It defines leaves as the food making organs of plants and discusses their external structures like the blade, petiole, and stipules. Leaves can be simple or compound. Photosynthesis takes place in leaves to produce glucose from carbon dioxide and water using sunlight. Leaves have several functions including producing oxygen, food, and reducing temperatures. The document examines leaf anatomy and types of leaves, distinguishing between simple, palmately compound, and pinnately compound leaves.

1. University of Salahaddin
College of Education
Biology department
By: Halala Rahman Qadir
M.Sc. Plant physiology
12/17/2013
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2. The objectives are:
1-Definition of leaf
2-Photosynthesis
3-The function of leaf
4-Types of leaf
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3. The definition of leaf
Leaf is an organ of a vascular plant, and the food
making factories of green plants. Leaves come in
many different shapes and sizes.
Leaf
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4. Structure of leaf
•
•
•
•
External Features
Leaf blade – Flattened part of the leaf
Petiole – Leaf stalk
Stipules – Leaf-like appendages at the base of the leaf.
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Figure (2): External structure of leaf
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5. Leaf
Leaves can be simple. They are made of a single
leaf blade connected by a petiole to the stem. An
oak leaf is an example.
A compound leaf is a leaf made up of separate
leaflets attached by a petiole to the stem like a
palm leaf.
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6. Photosynthesis
 The process of photosynthesis take
place in leaf of the plant to produce of
glucose
SUN
photons
chlorophyll
6CO2 + 6H2O  C6H12O6 + 6O2
glucose
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7. The functions of leaf
*They...
1. Produce oxygen for animals for respiration
2. Remove carbon dioxide from the air
3. Produce food for the plant
4. Create shade
5. Create hiding places for wildlife
6. Are a source of food (for animals and people)
7. Reduce soil erosion by intercepting rain as it falls
8. Lower the air temperature as a by product of
transpiration
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8. Leaf anatomy
A leaf is a plant organ and is made up of a
collection of tissues in a regular organization.
The major tissue systems present are:
The epidermis that covers the upper and lower
surfaces
The mesophyll inside the leaf that is rich in
chloroplasts (also called chlorenchyma)
The arrangement of veins (the vascular tissue)
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9. Leaf anatomy
Figure(1): Anatomy structure of the leaf
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10. Types of leaves
Simple leaf
compound leaf
Palmately
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Pinnately
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11. Types of leaf
*According to blade
1. Simple leaf: has one single blade
2. Compound leaf: has more than
single blade
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12. Types of leaf
Types of compound leaf
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13. Types of leaf
According to veins
Parallel- veined leaves: the veins run at the same distance
to other like in canes.
• Pinnate leaves: there is a main vein called midrib, from
which the other nerves derive, remembering a plume.
Palmate leaves: the nerves derive from main point such as
the fingers do in the palm of the hand.
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14. Types of leaf
Types of compound lead
Compound leaf
Palmately
Pinnately
Unifolate leaf
Unipinatley
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Bipinately
Tripinately
Bifoliate
leaf
Trifoliate
leaf
De compound leaves
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15. Types of compound leaf
Pinately simple leaf:
1. Uni Pinately: exp: Nem tree
2. Bi Pinately: exp: Acacia leaf
3. Tri Pinately: exp: Moringa leaf
4. Decompound Pinately: exp: Carrot leaf
BiPinately
Uni Pinately
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Tri Pinately
Decompound Pinately
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16. Types of compound leaf
Palmately compound leaf
1. Unifolite: ex: Citrus
2. Bifolite: ex: Gulmohar leaf
3. Triifolite: ex: Trifolium
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2
4. Quadrifoliate : ex: Penis quadrifolium
5. Mulifoliate : ex: Cotton tree
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17. References
1. Bayer, M. B. (1982). The New Haworthia Handbook.
Kirstenbosch: National Botanic Gardens of South Africa.
2. Couder, Y.; L. Pauchard.; C. Allain; M.Adda-Bedia; S.
Douady (2002). "The leaf venation as formed in a
tensorial field". The European Physical Journal B 28 (2):
135–138.
3. Mauseth, J. D. ( 2008). Botany: An Introduction to Plant
Biology. Publisher: Jones & Bartlett.
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18. Home work
Q/ What is the type of leaf in kidney
bean?
Q/ Write the factors that effect on
the process of photosynthesis?
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19. 12/17/2013
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