Tag: permanent tissues and their types

Questions Related to permanent tissues and their types

 A tissue whose cells have very thick cell wall are 

  1. Parenchyma

  2. Aerenchyma

  3. Sclerenchyma

  4. Both A and B


Correct Option: C
Explanation:

  1. A tissue whose cells have very thick cell wall are sclerenchyma. 
  2. The cells wall is rigid and lignified.
So, the correct answer is 'Sclerenchyma'.

Long plants are able to stand erect due to presence of

  1. Sclerenchyma

  2. Collenchyma

  3. Parenchyma

  4. Prosenchyma


Correct Option: A
Explanation:

Since plants do not have bones for structure and support they must have cell walls around all of their cells. This leads to the need for very unique cells in plants. Sclerenchyma cells are specialized plant cells that exist to provide strength and support. They are present in all kinds of plants including grasses, trees, and flowering plants.

So, the correct answer is 'Sclerenchyma.'

Sclerenchyma fibres are absent in

  1. Protoxylem

  2. Protophloem

  3. Metaxylem

  4. None of the above


Correct Option: A,B
Explanation:

Protoxylem and protophloem that develop in the primary stage of plants need living cells to divide and form more tissues to grow and as sclerenchymatous cells are dead and not divide so they lack sclerenchyma cells.

So the correct option is 'Protoxylem and Protophloem'.

Choose the incorrect statement.

  1. Permanent tissues having all cells similar in structure and function are called simple tissue.

  2. Complex tissue has different types of cells performing different functions altogether.

  3. Secondary meristem is lateral meristem.

  4. The cells of permanent tissues divide further.


Correct Option: D
Explanation:

  • Permanent tissues may be defined as a group of living or dead cells formed by meristematic tissue and have lost their ability to divide and have permanently placed at fixed positions in the plant body. Meristematic tissues that take up a specific role lose the ability to divide. This process of taking up a permanent shape, size and a function is called cellular differentiation. Cells of meristematic tissue differentiate to form different types of permanent tissues.
Simple tissues - A group of cells which are similar in origin; similar in structure and similar in function are called simple permanent tissue.
  • Complex permanent tissue - The complex tissue consists of more than one type of cells which work together as a unit. Complex tissues help in the transportation of organic material, water and minerals up and down the plants. That is why it is also known as conducting and vascular tissue.
  • Lateral Meristem - This meristem consists of cells which mainly divide in one plane and cause the organ to increase in diameter and growth. Lateral meristem usually occurs beneath the bark of the tree in the form of Cork Cambium and in vascular bundles of dicots in the form of vascular cambium. The activity of this cambium results in the formation of secondary growth.

So the correct option is 'The cells of permanent tissues divide further'.

Pits are found in the walls of

  1. Parenchyma 

  2. Sclerenchyma

  3. Collenchyma

  4. Both A and C


Correct Option: B
Explanation:

Pits are thin portions of the cell wall. Through pits, the communication and exchange of fluid takes place between cells.  There is no deposition of lignin in this area. They are found in the walls of dead tissues with lignified cell walls like sclerenchyma and tracheids and vessels of xylem.

Thus, the correct answer is 'Sclerenchyma.'

Stone cells is an alternative name of 

  1. Cortical fibres

  2. Sclereids

  3. Xylary fibres

  4. Phloem fibres


Correct Option: B
Explanation:

A. Cortical fibres are the extraxylary fibres present in cortex.

B. Sclereides are excessively thick walled short sclerenchyma cells.

C. Xylary fibres are the sclerenchyma fibres present in the xylem.

D. Phloem fibres are the sclerenchyma fibres present in the phloem.

So the correct answer is ‘sclereids’.

Sclerenchyma cells have thickening of

  1. Cellulose

  2. Lignin

  3. Silica

  4. Cellulose, silica


Correct Option: B
Explanation:

Sclerenchyma tissue possesses long, narrow cells with thickened walls. They possess secondary walls made of lignin. Lignin is a chemical substance, which acts as cement and hardens them. Therefore, option B is correct. 

Simple tissues are_________________

  1. Parenchyma, xylem and collenchyma

  2. Parenchyma, collenchyma and sclerenchyma

  3. Parenchyma, xylem and sclerenchyma

  4. Parenchyma, xylem and phloem


Correct Option: B
Explanation:

  • Simple permanent tissues are a group of cells with the same origin, structure and function are called simple permanent tissues.
  •  Parenchyma, collenchyma, and sclerenchyma are simple tissue which coordinates to perform a similar function.

So, the correct answer is option B.

Which simple permanent tissue is formed of dead cells?

  1. Collenchyma

  2. Sclerenchyma

  3. Aerechyma

  4. Xylem


Correct Option: B
Explanation:

Collenchyma, is the simple permanent mechanical tissue, formed of living cells. 

Sclerenchyma, is the simple permanent mechanical tissue, formed of dead cells.

Aerenchyma, is a type of parenchyma, simple permanent tissue, formed of living cells.

Xylem is a simple complex permanent tissue formed of the majority of dead cells. 

So, the correct answer is ‘Sclerenchyma’.

Sclereids belong to

  1. Xylem

  2. Parenchyma

  3. Collenchyma

  4. Sclerenchyma


Correct Option: D
Explanation:
A. Xylem is a complex permanent tissue which transports water and minerals from roots to other parts of the plants. It is composed of tracheids, vessels, xylem parenchyma and xylem fibres.
B. Parenchyma is a simple permanent tissue made up of thin walled living cells.
C. Collenchyma is a specialised simple permanent tissue which gives mechanical support to the plants.
D. Sclerenchyma is lignified supportive simple permanent tissue composed of thick walled and dead cells as the living protoplast is absent in the cells. Sclerenchyma consists of sclerenchyma fibres and sclereids.
So, the correct answer is 'Sclerenchyma'