Test: Plant Tissue - 1 - NEET MCQ

Anatomy : The study of internal structure of the plant with the help of section cutting is called Internal Morphology or Anatomy.

A group of structurally similar or dissimilar cells that perform a common function and have a common origin is called a tissue. A plant is made up of different kinds of tissues. The complex tissues are, however, composed of different kinds of cells and they perform different types of functions.

• A meristem may be defined as the group of cells which divide continuously to give rise to new cells.
• A meristem is the tissue in most plants containing undifferentiated cells, found in zones of the plant where growth can take place.
• Meristematic cells give rise to various organs of the plant and keep the plant growing.
• Meristematic cells are incompletely or not at all differentiated and are capable of continued cellular division. Furthermore, the cells are small and protoplasm fills the cell completely. The vacuoles are extremely small.
• The cytoplasm does not contain differentiated plastids, although they are present in rudimentary form- proplastids.
• Meristematic cells are packed closely together without intercellular cavities.
• The cell wall is a very thin primary cell wall.

Thus, the correct answer is option C.

Pollen of Pinus do not have meristems. A meristem is the tissue in most plants containing undifferentiated cells, found in zones of the plant where growth can take place. Meristematic cells give rise to various organs of the plant and keep the plant growing. Meristematic cells are incompletely or not at all differentiated, and are capable of continued cellular division.

Thus, the correct answer is option D.

Bamboo, grass and mint stem elongate by the activity of Intercalary meristems. Intercalary meristem at base of leaves or nodes of grasses is responsible for primary growth. Meristems are classified by their location as apical located at root and shoot tips, lateral in the vascular and cork cambia, and intercalary at internodes, or stem regions between the places at which leaves attach and leaf bases. Intercalary meristem cells possess the ability to divide and produce new cells, as do apical and lateral meristems. They differ, however, in being situated between regions of mature tissue, such as at the base of grass leaves, which are themselves located on mature stem tissue.
Thus, the correct answer is option C.

Maximum growth of root takes place in the back side portion of the root apex. Apex portion is made up of root cap and then follows the region of cell division where meristematic tissues are present.

• The packing tissues in plants that stores food, nutrients and water are called Parenchyma.
• Parenchyma with chlorophyll is called chlorenchyma and parenchyma with air is called aerenchyma.
• The intercellular gaps in Parenchyma are large.
• Aerenchyma is mostly present in aquatic plants and chlorenchyma is present in leaves.

• Collenchyma are the tissues responsible for flexibility in plants and provides support and strength for the plants.
• They have less intercellular spaces in between them.
• They allow bending of stems and leaves without breaking.
• Their cell walls are irregularly thickened.

The cork cambium is a lateral meristem and is responsible for secondary growth that replaces the epidermis in roots and stems. It is found in woody and many herbaceous dicots, gymnosperms and some monocots (monocots usually lack secondary growth).

Embryonic tissue in plants refers to the actively growing cells but more than often this term is used to describe the early formation of tissue during its first growth stages. It thus refers to the sporophyte, gametophyte embryos from seedlings as well as meristematic tissues which are always in embryonic state. Under this condition, the growth of this tissues takes place through cell division and the cells of the embryo divide.
Therefore, the correct answer is option C.

On the basis of origin and development, meristem is grouped as promeristem, primary and secondary meristem. Promeristem includes undifferentiated, actively dividing apical initials which are derived from embryonic tissues and give rise to primary meristem. Primary meristem is derived from promeristem or embryonic meristem and produce primary permanent tissues of primary plant body. Secondary meristem develops from permanent tissues during secondary growth and gives rise to secondary tissues. Secretory tissues are the permanent primary tissues, which are derived from promeristem.

Thus, the correct answer is option B

The root cap protects the growing tip in plants. It secretes mucilage to ease the movement of the root through soil, and may also be involved in communication with the soil microbiota. The purpose of the root cap is to enable downward growth of the root, with the root cap covering the sensitive tissue in the root.

• Sclerenchymatous cells are the dead cells responsible for stiffness in plants.
• The husk of a coconut is made of Sclerenchymatous tissue.
• They are of two kinds, namely, sclereids and fibers.
• Simple pits are present in thickened cell walls of sclerenchyma.

• Complex permanent tissues are made of many types of cells and comprises of Xylem and Phloem.
• Complex permanent tissues are made of many types of cells and comprises of Xylem and Phloem.
• Xylem contains mostly of dead cells and helps in conduction of water and minerals from roots to the stem and leaves.
• Tracheids are the dead cells that conduct water and minerals vertically.

Marginal meristem is the meristem located along the margin of a leaf primordium and forming the leaf blade. The apical meristem or growing tip, is a completely undifferentiated meristematic tissue found in the buds and growing tips of roots in plants. 
Intercalary meristems are capable of cell division, and they allow for rapid growth and regrowth of many monocots. Intercalary meristems at the nodes of bamboo allow for rapid stem elongation, while those at the base of most grass leaf blades allow damaged leaves to rapidly regrow. 
In mass meristem the cells divide in all planes to form bulk of tissue. this type of meristem takes part in the formation of cortex, pith, endosperm and sporangia. 
Therefore, the correct answer is option D. 

• Tracheids are tubular structures made of dead cells without protoplasm.
• Xylem vessels have lignified walls without protoplasm.
• Xylem parenchymatic tissues are made of thin-walled living cells and conduct water sideways.
• Xylem vessels are perforated and help in conduction of water to branches.

• Epidermal tissue system provides protection and stops too much loss of water and comprises of epidermis, stomata and epidermal appendages.
• Single continuous layer of compactly arranged parenchymatous cells that provides complete protection are present in epidermis.
• Cuticle provides water proof nature for leaves and stems and stomata regulates exchange of air and water.
• Stomata are surrounded by a pair of kidney-shaped cells called guard cells and the inner walls of stomata are comparatively thicker than that of outer walls.

• Parenchyma cells are thin-walled and are not specifically thickened, making them different from the other tissues mentioned.
• Collenchyma cells have thickened cell walls at the corners, providing mechanical support.
• Fibres and sclereids are types of sclerenchyma, which are characterized by having thick, lignified cell walls.
• Therefore, parenchyma is the tissue that does not have specifically thickened walls.

Parenchyma cells are living cells. They are at the constant state of division. They have large central vacuoles, which allow the cells to store and regulate ions, waste products and water. These are majorly distributed as ground tissue. Tissue specialised for food storage is commonly formed of parenchyma cells. 
Collenchyma and sclerenchyma involve in mechanical support. 
Aerenchyma involves in gas exchange.
Thus, option A is correct.

Parenchyma is a simple tissue which is composed of thin-walled polyhedral, isodiametric living cells with sufficient cytoplasm and one or more nuclei. These tissues serve the purpose of storage, photosynthesis gaseous exchange and much more but do not provide mechanical support to the plant and hence, lack cell wall thickening or lignin deposition which is a characteristic feature of mechanical tissues. They have cellulosic cell wall without any thickening or lignin deposition. Parenchymatous cells are characterized by the presence of well-developed intercellular spaces, as in the case of aerenchyma.
Therefore, the correct answer is option D.