Tag: leaf - external morphology

Questions Related to leaf - external morphology

Chlorophyll is a plant pigment that absorbs all frequencies of light except for

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Green

  2. Yellow

  3. Blue

  4. White

  5. red

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Correct Option: A
Explanation:

When white light is incident on an object , it absorbs some constituent colours of white light and some are reflected back , the combination of reflected colours decides the colour of an object that we see. 

We know that chlorophyll is of green colour , it means that it absorbs six constituent colours of white light and reflects only green colour i.e. it doesn't absorb green frequency.

The leaf in which the stomata remains confined to lower surface of the leaf is known as

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Amphistomatic

  2. Hypostomatic

  3. Epistomatic

  4. All of the above

Show answer
Correct Option: B
Explanation:

Amphistomatic: A leaf is said to be called as amphistomatic when the stomata is present on both the side of leaf.

Hypostomatic: A leaf is said to be hypostomatic when the stomata is present on the underside of the leaf.
Epistomatic: A leaf is said to be epistomatous where stomata are present on the adaxial surface only. Such type of leaf is found in aquatic plants where the leaves float on the surface of water, e.g. Nymphaea
Thus the correct answer is option B.

The leaf having stomata on both sides are known as 

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Amphistomatic

  2. Hypostomatic

  3. Epistomatic

  4. All of the above

Show answer
Correct Option: A
Explanation:

Amphistomatic: A leaf is said to be called as amphistomatic when the stomata are present on both the side of the leaf.

Hypostomatic: A leaf is said to be hypostomatic when the stomata are present on the underside of the leaf.
Epistomatic: A leaf is said to be epistomatic where stomata are present on the adaxial surface only. Such type of leaf is found in aquatic plants where the leaves float on the surface of water, e.g. Nymphaea. 
Thus the correct option is A.

In some plants like Nerium, stomata is present in a cavity known as 

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Trichomes

  2. Stomatal crypts

  3. Guard cell

  4. None of the above

Show answer
Correct Option: B
Explanation:

Stomata are the openings surrounded by the guard cells, present in the epidermis of the leaves. It helps in the gaseous exchange in plants. The position of guard cells varies in different plants on the basis of climate. They are found in cavities, called stomatal crypts in Nerium oleander (non-succulent xerophyte). They are sunken (lower the epidermis) in xerophytic plants to recuce the water loss. They are found in grooves in Ericales lined with epidermal hair. So, the correct answer is 'Stomatal crypts'.

The bulliform cells is also known as 

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Mesophyll cells

  2. Chlorenchyma cells

  3. Motor cell

  4. None of the above

Show answer
Correct Option: C
Explanation:

The large, bubble-shaped epidermal cells that occur on the upper surface of the leaves of monocots are called as bulliform cells. They are also called as motor cells. They help in the unfolding of developing leaves. It involves in the rolling and unrolling of mature leaves in response to alternating wet and dry periods.

Thus, the correct answer is 'Motor cell'.

The palisade tissue occurs on the ............ surface of the leaf.

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Adaxial

  2. Abaxial

  3. Both A and B

  4. None of the above

Show answer
Correct Option: A
Explanation:

Palisade parenchyma is found immediately below the upper epidermis. It is 2 to 3 layered, with compactly arranged tubular cells, rich in parietal chloroplasts. The adaxial surface is the upper surface of a leaf. The abaxial surface is the lower surface of a leaf.

Thus, the correct answer is 'Adaxial'.

Epistomatic stomata are mostly found in 

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Aquatic plants

  2. Terrestrial plants

  3. Xerophytic plant

  4. None of the above

Show answer
Correct Option: A
Explanation:

Epistomatic stomata is having stomata on the upper surface of the leaf. This type of stomata is mostly found in aquatic plants. Aquatic plants float on the surface of the water and therefore stomata are not found in the lower epidermis. Stomata are found on the upper epidermis because for direct exchange of gases between the leaf and the atmosphere. 

The cells which contain the crystal of calcium carbonate is known as 

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Guard cell

  2. Silica cell

  3. Idioblast

  4. None of the above

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Correct Option: C
Explanation:
Idioblasts are the crystal containing isolated plant cell. It is secretory in nature. the crystal is formed by the deposition of the inorganic materials like calcium salts. It is involved in the storage of reserve food, pigments, minerals, latex, gum, resin, tannin etc. So, the correct answer is option 'Idioblast'.

The air spaces in the leaf is created by 

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Chlorenchyma

  2. Aerenchyma

  3. Palisade parenchyma

  4. None of the above

Show answer
Correct Option: B
Explanation:
The spongy tissue that forms air spaces between the cells of leaves, stems and roots of some plants are called aerenchyma cells. It helps in the gaseous exchange between the shoot and the root and also provides buoyancy to the aquatic plants. So, the correct option is 'Aerenchyma'.

Which of the following cells helps in the rolling of leaves in dry weather?

botany leaf - external morphology morphology of leaf structure of a leaf the leaf

  1. Bulliform cells

  2. Guard cell

  3. Parenchyma cell

  4. None of the above

Show answer
Correct Option: A
Explanation:

Bulliform cells are found in the axial or upper surface of the epidermis of monocots. These are large, colourless, bubble-shaped (empty) cells found in clusters near the mid vein. In the presence of insufficient water, these cells loose water and become flaccid. In response to this condition, the leaf rolls inward (to expose the minimum part of the leaf) to minimise the water loss. So, the correct 'Bulliform cells'.