Plant Tissues Practice Questions
40 free Plant Tissues practice questions for the General Science. Tap an option to answer — you get instant feedback, the correct answer, and a detailed explanation for every question.
Which type of plant tissue is composed of actively dividing cells and is responsible for the primary growth of the plant?
- A Parenchyma tissue
- B Sclerenchyma tissue
- C Meristematic tissue
- D Phloem tissue
Correct answer: Meristematic tissue
Meristematic tissues consist of undifferentiated cells that continuously divide to produce new cells. They are found in growing regions like the tips of roots and shoots, facilitating the plant's increase in length and girth.
The increase in the girth (diameter) of a plant stem is primarily due to the activity of which tissue?
- A Apical meristem
- B Lateral meristem
- C Intercalary meristem
- D Apical bud
Correct answer: Lateral meristem
Lateral meristems, including the vascular cambium and cork cambium, are responsible for secondary growth. This process increases the thickness of the stems and roots in woody plants.
Which simple permanent tissue is characterized by thin cell walls and large vacuoles, and is primarily involved in photosynthesis and food storage?
- A Collenchyma
- B Sclerenchyma
- C Parenchyma
- D Xylem
Correct answer: Parenchyma
Parenchyma is the most common and versatile plant tissue. Its cells remain living at maturity and perform essential functions such as metabolic processes, starch storage, and wound healing.
Which of the following tissues provides mechanical support and flexibility to young, growing plant organs like petioles?
- A Sclerenchyma
- B Parenchyma
- C Collenchyma
- D Aerenchyma
Correct answer: Collenchyma
Collenchyma cells have unevenly thickened primary cell walls, usually at the corners. This allows them to provide structural support while still being flexible enough to permit growth in elongating stems and leaves.
What is the primary characteristic of sclerenchyma tissue that distinguishes it from parenchyma and collenchyma?
- A Cells remain living and active at maturity
- B Cells possess thin, flexible cellulose walls
- C Cells die at maturity with lignified walls
- D Cells contain high amounts of chlorophyll
Correct answer: Cells die at maturity with lignified walls
Sclerenchyma cells develop thick secondary walls impregnated with lignin. Once they reach functional maturity, the cells die, leaving behind a rigid 'skeleton' that provides intense structural reinforcement.
Which component of the xylem is responsible for the upward conduction of water and minerals in angiosperms?
- A Phloem sieve tubes
- B Vessels and tracheids
- C Phloem companion cells
- D Lignified phloem fibers
Correct answer: Vessels and tracheids
Vessels and tracheids are the specialized water-conducting elements of the xylem. Both are tube-like structures with lignified walls that allow for the efficient transport of water from the roots to the rest of the plant.
Sieve tubes and companion cells are the functional units of which complex tissue?
- A Xylem
- B Epidermis
- C Phloem
- D Periderm
Correct answer: Phloem
Phloem is the vascular tissue responsible for the translocation of organic nutrients, particularly sucrose. Sieve tubes conduct the sugars, while companion cells provide metabolic support to the sieve tube elements.
The protective outer layer of a plant, which prevents water loss and provides a barrier against pathogens, is called the:
- A Endodermis
- B Epidermis
- C Vascular bundle
- D Cortex
Correct answer: Epidermis
The epidermis is a dermal tissue system that covers the entire surface of the plant. It is often coated with a waxy cuticle that helps the plant retain moisture and protects against environmental stress.
Which specialized epidermal cells regulate the opening and closing of stomata for gas exchange?
- A Trichomes
- B Guard cells
- C Subsidiary cells
- D Bulliform cells
Correct answer: Guard cells
Guard cells are pairs of bean-shaped cells that flank each stoma. By changing their turgor pressure, they expand or contract to open or close the pore, balancing carbon dioxide intake with water vapor loss.
Which of the following is a type of sclerenchyma that is commonly found in the gritty texture of pear fruit?
- A Fibers
- B Sclereids
- C Vessel elements
- D Tracheids
Correct answer: Sclereids
Sclereids (also known as stone cells) are short, irregularly shaped sclerenchyma cells with very thick lignified walls. They provide hardness to seed coats and nut shells, as well as the gritty texture in certain fruits.
In aquatic plants, a specialized parenchyma with large air cavities that provide buoyancy is known as:
- A Chlorenchyma
- B Aerenchyma
- C Phyllode
- D Velamen
Correct answer: Aerenchyma
Aerenchyma contains large intercellular air spaces. This tissue helps hydrophytes stay afloat and facilitates the diffusion of gases like oxygen to submerged tissues.
Which tissue in the root is responsible for regulating the flow of water and minerals into the vascular cylinder via the Casparian strip?
- A Exodermis
- B Pericycle
- C Endodermis
- D Central pith
Correct answer: Endodermis
The endodermis is the innermost layer of the root cortex. Its cell walls contain a waxy band called the Casparian strip, which forces water to pass through the plasma membranes, acting as a selective filter.
Which of the following xylem elements is considered the only living component of the xylem tissue?
- A Xylem tracheids
- B Vessel elements
- C Xylem parenchyma
- D Lignified xylem fibers
Correct answer: Xylem parenchyma
While tracheids, vessels, and fibers are dead at maturity to facilitate water flow and support, xylem parenchyma remains living. It functions in the storage of starch and fats and assists in the lateral transport of water.
The 'wood' of a tree is scientifically referred to as:
- A Secondary phloem
- B Primary xylem
- C Secondary xylem
- D Cork
Correct answer: Secondary xylem
Wood is composed of the layers of secondary xylem produced annually by the vascular cambium. Over time, these lignified cells accumulate to form the bulk of the tree trunk.
Which meristematic tissue is found at the base of leaves or internodes in monocots like grasses, allowing them to regrow after being grazed?
- A Shoot apical meristem
- B Intercalary meristem
- C Lateral cambial meristem
- D Floral meristem
Correct answer: Intercalary meristem
Intercalary meristems are located between regions of mature tissue. They enable rapid stem elongation and help grasses recover quickly after the tips have been removed by lawnmowers or herbivores.
What is the primary role of the 'pericycle' tissue in plant roots?
- A Absorption of water
- B Protection of the epidermis
- C Initiation of lateral roots
- D Photosynthesis
Correct answer: Initiation of lateral roots
The pericycle is a layer of cells just inside the endodermis. It retains meristematic capability and is the site where lateral (branch) roots originate.
Which part of the phloem is unique for having no nucleus at maturity but remains metabolically active?
- A Phloem companion cell
- B Phloem parenchyma
- C Sieve tube element
- D Phloem fiber
Correct answer: Sieve tube element
Sieve tube elements lose their nucleus, ribosomes, and vacuoles to maximize the space for sugar transport. They rely on the adjacent companion cells to perform necessary genetic and metabolic functions.
The waxy substance 'suberin' is a major component of which plant tissue?
- A Leaf epidermis
- B Secondary xylem
- C Outer cork layer
- D Collenchyma tissue
Correct answer: Outer cork layer
Suberin is a waterproof, fatty substance found in the walls of cork cells. It makes the outer bark of woody plants impermeable to water and gases, protecting the inner tissues.
Trichomes are hair-like outgrowths of which tissue system?
- A Vascular tissue system
- B Ground tissue system
- C Dermal tissue system
- D Secretory tissue system
Correct answer: Dermal tissue system
Trichomes are specialized epidermal cells. They can help reduce transpiration, reflect excess sunlight, or secrete sticky/toxic substances to deter herbivores.
Pith and cortex are parts of which tissue system in a plant?
- A Dermal tissue system
- B Vascular tissue system
- C Ground tissue system
- D Epidermal tissue system
Correct answer: Ground tissue system
The ground tissue system makes up the bulk of the plant body. It includes the pith (center of the stem) and cortex (outer region), primarily consisting of parenchyma, collenchyma, and sclerenchyma cells.
Which of the following is the primary meristem that gives rise to the vascular tissues, xylem and phloem?
- A Protoderm
- B Ground meristem
- C Procambium
- D Phellogen
Correct answer: Procambium
The procambium is the primary meristematic tissue that differentiates into the primary vascular system. It ensures the continuous development of water and food conducting tissues during the plant's primary growth.
The 'Kranz anatomy' is a specialized arrangement of tissues found in the leaves of:
- A C3 plants
- B C4 plants
- C CAM plants
- D Hydrophytes
Correct answer: C4 plants
Kranz anatomy features a ring of bundle sheath cells surrounding the vascular bundles, which is a characteristic adaptation of C4 plants to increase photosynthetic efficiency under high temperatures.
Which of the following tissues is characterized by highly thickened corners of cellulose and pectin, providing tensile strength?
- A Parenchyma
- B Sclerenchyma
- C Collenchyma
- D Aerenchyma
Correct answer: Collenchyma
Collenchyma cells have localized wall thickenings at the corners. This tissue provides mechanical support while remaining flexible, which is essential for young, growing stems and leaf stalks.
The 'Exodermis' is a specialized outer layer of the cortex found in the roots of many plants; it is functionally similar to the:
- A Epidermis
- B Endodermis
- C Pericycle
- D Hypodermis
Correct answer: Endodermis
The exodermis often develops Casparian strips and suberin deposits similar to the endodermis. It acts as a secondary protective barrier and regulates water and ion movement in older root regions.
What is the name of the lateral meristem that produces the secondary phloem and secondary xylem?
- A Cork cambium
- B Intercalary meristem
- C Vascular cambium
- D Apical meristem
Correct answer: Vascular cambium
The vascular cambium is a ring of meristematic tissue in woody plants that divides to produce secondary xylem (wood) toward the inside and secondary phloem toward the outside.
Which of the following cells are associated with sieve tubes in angiosperms to help in the pressure-flow mechanism?
- A Albuminous cells
- B Companion cells
- C Subsidiary cells
- D Bulliform cells
Correct answer: Companion cells
Companion cells are specialized parenchyma cells that share a common origin with sieve tube elements. They contain a nucleus and organelles, providing metabolic support to the enucleated sieve tubes.
The presence of 'Lenticels' in the bark of woody stems primarily facilitates:
- A Water absorption
- B Gaseous exchange
- C Photosynthesis
- D Food storage
Correct answer: Gaseous exchange
Lenticels are lens-shaped openings in the periderm of woody stems and roots. They allow for the exchange of gases between the internal tissues and the atmosphere when the stomata are replaced by bark.
Which specific tissue is responsible for the formation of lateral roots in dicot plants?
- A Endodermis
- B Pericycle
- C Epidermis
- D Cortex
Correct answer: Pericycle
In roots, lateral roots originate endogenously from the pericycle, which is the outermost layer of the vascular cylinder. This allows the new root to connect directly to the primary vascular system.
In a dorsiventral leaf, the tissue located between the upper epidermis and the vascular bundles is called:
- A Loosely arranged spongy mesophyll tissue
- B Bundle sheath
- C Hypodermis
- D Palisade parenchyma
Correct answer: Palisade parenchyma
The palisade parenchyma consists of elongated, vertically arranged cells packed with chloroplasts. It is located just below the upper epidermis to maximize light absorption for photosynthesis.
What is the function of 'Hydathodes' in plants?
- A Osmosis
- B Nitrogen fixation
- C Secondary growth
- D Guttation
Correct answer: Guttation
Hydathodes are specialized pores, usually found at the leaf margins, through which water is expelled in liquid form. This process, known as guttation, typically occurs under conditions of high root pressure.
The 'Phelloderm' is a tissue produced by the activity of the Phellogen toward the:
- A Inside
- B Outside
- C Both sides equally
- D Below
Correct answer: Inside
The phellogen (cork cambium) divides to produce phellem (cork) toward the exterior and phelloderm (secondary cortex) toward the interior of the stem or root.
Which of the following is a non-living cell at maturity that functions in providing extreme mechanical rigidity?
- A Collenchyma
- B Chlorenchyma
- C Sclereid
- D Fibers
Correct answer: Sclereid
Sclereids are a type of sclerenchyma cell with extremely thick, lignified walls. They are dead at maturity and provide structural strength to seed coats, nut shells, and fruit pulps.
The 'Heartwood' of a tree differs from 'Sapwood' because heartwood is:
- A Actively conducting water
- B Found in the outer, still-growing layers of the trunk close to the bark
- C Filled with tannins and resins and is non-functional in transport
- D Composed of living parenchyma cells
Correct answer: Filled with tannins and resins and is non-functional in transport
Heartwood is the central, older wood of a tree. It is darker and more durable due to the accumulation of organic compounds like resins and tannins, and it no longer conducts water.
In monocot stems, the vascular bundles are described as 'closed' because they lack:
- A Xylem
- B Phloem
- C Cambium
- D Sieve tubes
Correct answer: Cambium
Closed vascular bundles lack a cambium layer between the xylem and phloem. This means monocot stems generally do not undergo typical secondary growth (thickening).
Which tissue system includes the stomata and epidermal hairs?
- A Ground tissue system
- B Vascular tissue system
- C Secretory tissue system
- D Epidermal tissue system
Correct answer: Epidermal tissue system
The epidermal tissue system forms the outermost protective covering of the plant body. It includes the epidermis, guard cells (stomata), and various appendages like trichomes and root hairs.
The 'Mesophyll' of a leaf is primarily composed of which type of tissue?
- A Collenchyma
- B Sclerenchyma
- C Xylem
- D Parenchyma
Correct answer: Parenchyma
Mesophyll is the ground tissue of the leaf located between the epidermal layers. It consists of specialized parenchyma cells (palisade and spongy) that contain chloroplasts for photosynthesis.
Which of the following terms describes a vascular bundle where phloem surrounds the xylem?
- A Collateral
- B Bicollateral
- C Amphivasal
- D Amphicribral
Correct answer: Amphicribral
In an amphicribral (hadrocentric) bundle, the phloem completely surrounds the xylem. This is a type of concentric vascular bundle common in many ferns.
The tissue that remains 'quiescent' or inactive in the root apex unless damage occurs is the:
- A Quiescent center
- B Root cap calyptrogen layer
- C Procambium
- D Protoderm
Correct answer: Quiescent center
The quiescent center is a region in the root apical meristem where cell division proceeds at a very slow rate. It acts as a reservoir of cells that can replace damaged initials.
What is the primary substance that makes 'cork' cells impermeable to water?
- A Lignin
- B Cellulose
- C Pectin
- D Suberin
Correct answer: Suberin
Cork cells (phellem) become heavily impregnated with suberin, a waxy, waterproof fatty substance. This makes the outer bark an effective barrier against water loss and pathogens.
Which of the following is an example of a secretory tissue in plants?
- A Laticifers
- B Tracheids
- C Sclereids
- D Companion cells
Correct answer: Laticifers
Laticifers are specialized cells or ducts that produce and store latex. They are a form of internal secretory tissue found in various plant families like Euphorbiaceae.