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PLANT MAGAZINE

 

 

 

THE PLANTS:

FLOWERS

STEMS AND BUDS

FRUITS

ROOTS

SEEDS

GLOSSARY

   

 

Types of leaves

THE LEAF: FUNCTIONS



The leaf is one of the most important part of the plants because it is the one which is in charge of accomplishing the photosynthesis, the respiration and transpiration

.

THE LEAF: PARTS


There are different types of leaves, which let us to distinguish the different kinds of plants, but essentially, each leaf is formed by the following parts:

A) THE BLADE

1.- VEINS AND MIDRIB (MIDVEIN)

2.-
MARGIN OR EDGE



B) PETIOLE


The blade is the expanded part of the leaf. It is the most conspicuous part , what most of people identify and understand as a leaf when such a noun is mentioned.

Different types of blade

Inside the blade the following parts can be distinguished:

-theveins : are a like wrinkles or pipes running along the blade. They are really the vascular bundles coming from the stem throughout the petiole into the the surface of the blade. The central vein is called Midrib. The different patters they draw in different species is a trait used by botanists to distinguish a plant from the other.


-The margin is the rim or final limit of the blade. It can offer different forms:

Different types of margin

The petiole is the connexion of the stem to the blade. It is the channel for the vascular bundles to arrive to it. It can be short or long. Those leaves having a petiole, no matter how long it may be, are called petiolated .There are some leaves without petiole. In this case they are called stalkless or sessile.

A petiolated leaf and a stalkless one

TEST

Test what you have learned about the leaf, clicking what you think is the correct answer among the three different possibilities.

1)The extended part of the leaf is called:

- petiole

- edge

-blade

2) The central vein of the blade is called:

- margin

- midrib

- stem

3) The channels that distribute the sap or circulatory fluids along the leaf are called:

- veins

-tunnels

-roots

4) Choose the correct statement:

-all the leaves are petiolated.

-all the leaves have a blade.

-all the leaves are sessile.
















 

 

 

 

 

 

 

 
 
 
 

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