Tag: botany

Quizzes (264) Questions (5276)

Questions Related to botany

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Tyloses are found in

  1. Sclereids

  2. Sclerenchyma fibres

  3. Secondary phloem

  4. Secondary xylem
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Tyloses are generally the outgrowth protruding from the parenchyma cells of xylem vessels. It generally protects the vascular tissue during stress like drought or infection. During unfavourable conditions, it falls from the sides of the cells and dam up the vascular tissue to prevent further damage to the plant. It can be traced in the secondary xylem. It aids in the process of making sapwood into heartwood in some hardwood trees, especially in trees with larger vessels. These blockages can be used in addition to gum plugs as soon as vessels become filled with air bubbles, and they help to form a stronger heartwood by slowing the progress of rot.
Thus, the correct answer is option D.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Tissue which develops more due to scarcity of water

  1. Sclerenchyma

  2. Collenchyma

  3. Parenchyma

  4. Meristem
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Tissue which develops more due to the scarcity of water is sclerenchyma. Sclerenchyma is the supporting tissue in plants. Two types of sclerenchyma cells exist: fibres and sclereids. Their walls consist of cellulose, hemicellulose, and lignin. Sclerenchyma cells are the principal supporting cells in plant tissues that have ceased elongation. Sclerenchyma is composed of dead cells with extremely thick cell walls -secondary walls that make up to 90% of the whole cell volume.
Thus, the correct answer is option A.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Sclerenchymatous cells in their cell walls have large percentage of

  1. Cellulose

  2. Pectin

  3. Lignin

  4. Silica
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sclerenchyma is a simple permanent tissue which is mainly composed of dead cells. The walls consist of cellulose, hemicellulose and lignin. These are the principal supporting cells in plant tissues that have ceased elongation. 

So, the correct answer is option C.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Fibre (longest plant cell), belongs to which tissue?

  1. Parenchyma

  2. Collenchyma

  3. Sclerenchyma

  4. Aerenchyma
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Sclerenchyma is a simple permanent tissue which is mainly composed of dead cells. The walls consist of cellulose, hemicellulose and lignin. These are the principal supporting cells in plant tissues that have ceased elongation. 
Sclerenchyma fibres are of great economical importance, since they constitute the source material for many fabrics (flax, hemp, jute, ramie).

So, the correct answer is option C.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

The function of hypodermis is

  1. Protection

  2. Hardness

  3. Support

  4. Storage
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The protoderm mainly differentiates to form the dermal layer which is known as epidermis, hypodermis, and endodermis. Hypodermis (exodermis) is the outermost layer of cells in the plant cortex. These cells are modified to give additional structural support or to store food materials or water. After the loss of the piliferous layer of the root, the hypodermis takes over the protective functions of the epidermis.
Thus, the correct answer is option C.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Senescence and death are essential in the function of

  1. Sieve tubes

  2. Companion cells

  3. Both A and B

  4. Xylem and sclerenchyma cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Senescence refers to the loss of functional capacity causing a cellular breakdown and metabolic failure. It is a characteristic feature of the period between reproductive maturity and death of a plant or plant part or cell, which ultimately causes cell death. 

A mature sieve tube is composed of vertical cells placed one above other with perforated sieve plates at their lateral walls to serve as the main conducting element of phloem. They lack nucleus but are living cells. 
Companion cells are live cells. They have a prominent elongated nucleus, which compensates for the absence of nucleus in sieve tubes. 
A sclerenchymatous cell is thick walled dead lignified cells without meristematic activity. These cells lack nucleus and protoplasm at their maturity. 
Xylem is a complex tissue and is made up of tracheids, vessels, fibers and parenchyma and serve in the ascent of sap. Except for xylem parenchyma, all other xylem components are dead and lack nucleus and protoplasm at their maturity. Thus, option D is the correct answer. 

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Hard, lignified, thick-walled, long and pointed cells constitute

  1. Parenchyma

  2. Collenchyma

  3. Sclereids

  4. Sclerenchyma
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Sclerenchyma cells have thick lignified secondary walls and often die when mature. It provides the main structural support to a plant. They are long and pointed cells. 

Parenchyma cells have thin primary walls and usually remain alive after they become mature. It forms the filler tissue in the soft parts of plants. 
Collenchyma cells have thin primary walls with some areas of secondary thickening. Collenchyma provides extra structural support, particularly in regions of new growth. 
Sclereids are a reduced form of sclerenchyma cells with highly thickened, lignified cellular walls that form small bundles of durable layers of tissue in most plants. Sclereids are relatively short. 

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Tissue which develops more due to scarcity of water is

  1. Sclerenchyma

  2. Collenchyma

  3. Parenchyma

  4. Meristem
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Parenchyma is a simple living tissue, which is composed of thin-walled polyhedral, isodiametric living cells with sufficient cytoplasm and one or more nuclei. 

Collenchyma is simple living tissue with thick non-lignified walls and uneven deposition of cellulose and pectin. They are derived from parenchyma and serve to impart tensile strength to growing parts. 
Meristem is a simple living tissue with dense cytoplasm and prominent nucleus; they divide and form new cells. 
Parenchyma, collenchymas, and meristem tissues need water to maintain living cytoplasm and nucleus and thereby to perform physiological  functions. 
Sclerenchyma is a dead tissue with thick lignified cell walls, which makes it hard and tough. They lack nucleus and cytoplasm and thus do not need water to maintain their functionality.
So, the correct answer is option A.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

The main function of sclerenchyma is to help in the ___________________.

  1. Conduction of food

  2. Synthesis of food

  3. Exchange of gases

  4. Mechanical support
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Conduction of food from leaves to other parts of the plant is carried out by phloem cells. 
The synthesis of food is carried out by chlorenchyma cells. These are parenchyma cells with chlorophyll pigments. 

Exchange of gasses is carried out by stomata, which are small pores present on leaf epidermis.   
Sclerenchyma is a type of permanent tissue. They are dead, long, thin narrow cells with thickened walls without any internal space. This tissue makes the plant hard and stiff. This aids in mechanical support to plant. 
So, the correct answer is option D.

Multiple choice botany plant tissues permanent tissues and their types simple permanent tissues tissues: plant tissues

Hard, lignified, thick-walled, long and pointed cells in plants are

  1. Parenchyma

  2. Sclerenchymatous fibre

  3. Collenchyma

  4. Sclereids
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sclerenchyma is the simple permanent tissue. It commonly forms the protective covering of the nuts and fruits but it also forms the ground tissue which supports different  specialized cells. Their walls consist of cellulose, hemicellulose, and lignin. 

Sclerenchyma fibers are of great economical importance since they constitute the source material for many fabrics. Unlike the collenchyma, mature sclerenchyma is composed of dead cells with extremely thick cell walls that make up to 90% of the whole cell volume. It is the hard, thick walls that make sclerenchyma cells important strengthening and supporting elements in plant parts that have ceased elongation. Fibres or bast are generally long, slender, so-called parenchymatous cells, usually occurring in strands or bundles. Such bundles or the totality of a stem's bundles are colloquially called as fibres. 
So, the correct answer is option B.