Botany anatomy

2. • NAME :FAIMA NAZIR
• ROLL NO: 11031506-040
• DISCIPLINE: BS(HONS)BOTANY
• SEMESTER: 6th
• COURSE TITLE: PLANT ANATOMY
• COURSE CODE: BOT-307
• SUBMITTED TO: M’AM TAYBA
• U O G

3. TOPIC
ANATOMY OF LEAVES

4. TYPES OF LEAVES
There are two types of leaves
1. Dorsilventral
leaves(dicotyledonous)
2. Isobilatral
leaves(monocotyledonous)

5. ANATOMY OF DICOTYLEDONOUS
LEAF
A leaf consists of following layers.
1. Cuticle
2. Upper epidermis
3. Lower epidermis
4. Pores also known as stoma /stomata
5. Mesophyll Tissue
1.Palisade mesophyll
2.Spongy mesophyll

7. CUTICAL
1. The outer thick waxy covering of the plants
and leaves.
2. Cuticle protects plant from drying out by
reducing water loss.
3. Does not let oxygen or carbon dioxide pass
through it.

9. UPPER EPIDERMIS
• Upper epidermis consists of a single layer of
cells covered by cuticle. Sometime contains
pores which allow gas or water molecule to
pass through it.

10. LOWER EPIDERMIS
• Below the spongy mesophyll is the lower
epidermis. We will see vascular bundle here
and stomata.

11. STOMATA
• The pore like openings in the underside of the
leaf is called stoma (singular) and stomata
(plural).
• Each stoma consists of two guard cells which
control the opening and closing of the stomata

13. FUNCTION OF STOMATA
• Stomata allow carbon dioxide and oxygen
and water vapor diffuse into and out of the
leaf by opening and closing .
• If the stomata were kept open all the time,
water loss due to transpiration would be so
great that few plants would be able to take
enough water to survive.

15. MESOPHYLL TISSUE
• There are two type of mesophyll tissue
1.Palisade mesophyll
• Just beneath the epidermis there are column
shaped cells containing chloroplast are known
as Palisade mesophyll .
• Most photosynthesis takes place here.

16. 2. Spongy mesophyll
• The second type of mesophyll tissue is the
spongy mesophyll which is composed of
closely packed irregular shape cells surronded
by air spaces.
• There are fewer chloroplast because they are
under side of the leaves

18. ANATOMY OF MONOCOTYLEDONOUS
LEAF
• Most of monocotyledonous leaves are nearly
erect and more or less both surfaces usually
receive direct and equal amount of sunlight.
Such leaves are called isobilateral
leaves(monocotyledonous).
• e.g Zea maize (MAIZE)

19. ANATOMY OF ZEA MAYS (MAIZE)-
MONOCOT
• EPIDERMIS
• The epidermis is found on both upper and
lower surfaces of the leaf.
• Epidermal layer are uniseriate.
• Stomata are confined to both the epidermal
layers

20. • MESOPHYLL
• It is not differentiated into palisad and spongy
tissue.
• Thin walled, isodiametric chlorophyllous cells
having intercellular spaces amoung them.
• VASCULAR BUNDLES
• Collateral and closed in shape
• Smaller in size
• Bundle sheath contain starch grain
• xylem consist of vessels and phloem of sieve
tube and companion cells
• Sclerencyma cells give mechanical support to
the leaf