Mix Example - TISSUES Questions in English

(A) Sclerenchyma is a permanent tissue that is entirely composed of dead cells with thick,lignified walls.
In contrast,Parenchyma and Collenchyma are simple permanent tissues composed of living cells.
Epithelial tissue is an animal tissue composed of living cells.

(B) Meristematic tissues are actively dividing cells and are not permanent tissues. They are characterized by dense cytoplasm,thin cell walls,and the absence of vacuoles. Permanent tissues are derived from meristematic tissues after they lose the ability to divide. Therefore,the statement that apical and intercalary meristems are permanent tissues is incorrect.

(C) The apical meristem is responsible for the increase in the length of the stem and root.
Intercalary meristem is found at the internodes and helps in the growth of leaves and internodes.
Lateral meristem (also known as cambium) is responsible for the increase in the girth or diameter of the stem and root in plants.

(D) perforated cell wall is a characteristic feature of conducting elements in plants that facilitate the transport of materials.
$1$. Tracheids and Vessels are xylem elements involved in water transport and possess perforated or pitted walls.
$2$. Sieve tubes are phloem elements involved in food transport and have perforated end walls called sieve plates.
$3$. Companion cells are specialized parenchyma cells associated with sieve tubes. They are living cells with a dense cytoplasm and a nucleus,and they do not possess perforated cell walls.

(A) The intestine is lined with columnar epithelium,which is specialized for absorption and secretion.
Stratified squamous epithelium is found in the skin and provides protection against wear and tear.
Cuboidal epithelium is typically found in ducts of glands and kidney tubules,providing structural support and secretion.
Spindle fibres are part of the cytoskeleton involved in cell division,not a type of epithelial tissue.

(B) Ligaments are specialized connective tissues that connect one bone to another bone at joints. When a person meets with an accident,the excessive force can cause these ligaments to tear or break. Since ligaments provide stability to the joints,their rupture leads to the displacement of bones from their normal position,which is known as dislocation.

(C) Skeletal muscles are responsible for voluntary movement,and therefore,movement in limbs like hands and legs is facilitated by the contraction or relaxation of skeletal muscles.
$A$ tendon is a fibrous connective tissue that attaches a muscle to a bone.
When skeletal muscles contract,they pull on the tendons,which in turn pull the bones to create movement.
Therefore,option $C$ is correct.

(D) Muscles can be classified based on their control as voluntary or involuntary.
Skeletal muscles are voluntary muscles because their movement is under our conscious control. They are also known as striated muscles due to their striped appearance.
Smooth muscles are involuntary muscles found in the walls of internal organs,and their movement is not under conscious control.
Cardiac muscles are involuntary muscles found in the heart,responsible for rhythmic contractions.
Therefore,both smooth muscles $(ii)$ and cardiac muscles $(iii)$ act involuntarily.

(A) Meristematic tissues consist of actively dividing cells that are restricted to specific regions of the plant,such as the tips of roots and shoots.
These tissues are responsible for the growth of the plant body.
Unlike permanent tissues,meristematic cells retain the ability to divide throughout their life.

(B) The epidermis is the outermost protective layer of the plant body. Its primary functions include protection against mechanical injury,prevention of water loss,and regulation of gaseous exchange through stomata. Conduction of water is the primary function of the $Xylem$ tissue,not the epidermis.

(C) Tendons are fibrous connective tissues that are very strong and have limited flexibility,not fragile. Therefore,the statement that tendons are non-fibrous and fragile is incorrect.

(D) Cartilage is a type of specialized connective tissue. It is found in the nose,ear,larynx,and trachea. The kidney is an organ composed primarily of epithelial tissues and nephrons,not cartilage.

(A) Adipose tissue is a specialized type of connective tissue that functions primarily to store fat. It consists of adipocytes,which are cells specialized for the storage of lipids. These tissues are found beneath the skin,around internal organs,and in the bone marrow,providing insulation and energy reserves for the body.

(B) Bone is a connective tissue that provides a structural framework to the body. The bone cells (osteocytes) are embedded in a hard,non-pliable matrix. This matrix is primarily composed of calcium and phosphorus salts,which provide strength and rigidity to the bones.

(C) Muscles possess the unique ability to contract and relax,which allows for movement. This property is due to the presence of specialized contractile proteins,primarily $Actin$ and $Myosin$,within the muscle fibers. Therefore,contractile proteins are found in muscles.

(D) Voluntary muscles,also known as skeletal muscles,are attached to bones and are under our conscious control.
They are responsible for the movement of body parts like arms and legs.
The muscles in the alimentary canal,bronchi of lungs,and iris of the eye are involuntary muscles,meaning they are not under our conscious control.

(A) Nervous tissue is primarily composed of neurons and neuroglia, which are responsible for the transmission and processing of electrical signals. The $brain$, $spinal cord$, and $nerves$ are the primary components of the nervous system and are rich in nervous tissue. $Tendons$, on the other hand, are a type of dense regular connective tissue that connects muscles to bones. Therefore, nervous tissue is not found in tendons.

(B) nerve cell,also known as a neuron,is the fundamental unit of the nervous system. It consists of a cell body (cyton),dendrites,and an axon with nerve endings. Tendons are a type of dense regular connective tissue that connects muscle to bone. Therefore,tendons are not a component of a nerve cell.

(C) Areolar tissue is a type of loose connective tissue that acts as a supporting and packing tissue between organs. It fills the space inside the organs,supports internal organs,and plays a crucial role in the repair of tissues after an injury.

(D) Cardiac muscles are involuntary muscles present in the heart.
They are specialized to contract and relax rhythmically throughout an individual's life without getting fatigued.
This continuous action ensures that the heart keeps pumping blood to all parts of the body without stopping.

(A) Chondrocytes are the specialized cells found in the cartilaginous tissue (cartilage) of the body.
$A$. Chondrocytes: Found in cartilage.
$B$. Basophils: $A$ type of white blood cell found in the blood.
$C$. Osteocytes: Mature bone cells found in bone tissue.
$D$. Mast cells: Found in connective tissues like areolar tissue.

(B) Phloem is a complex permanent tissue responsible for the translocation of food in plants. It consists of four types of elements: sieve tubes,companion cells,phloem parenchyma,and phloem fibres. Among these,phloem fibres (also known as bast fibres) are the only dead elements,as they possess thick lignified cell walls and lack protoplasm at maturity. The other three elements are living at maturity.

(C) Companion cells are specialized parenchyma cells found in the phloem of angiosperms. Unlike sieve tube elements,which lose their nucleus and other organelles at maturity to facilitate the transport of food,companion cells retain their nucleus and dense cytoplasm to regulate the metabolic activities of the sieve tube elements.

(D) The $cuticle$ is a waxy, water-repellent protective layer covering the epidermis of leaves and stems. In desert plants, this layer is often thick to minimize transpiration and protect the plant from excessive heat, thereby reducing the rate of water loss.

(B) Xylem parenchyma is the only living component of the xylem tissue. It is responsible for the lateral conduction of water and the storage of food materials in plants. Xylem vessels are primarily involved in the vertical conduction of water. Parenchyma and collenchyma are simple permanent tissues that do not participate in the conduction of water.

(B) Intercalary meristem is located at the base of leaves or internodes (the region between two nodes).
It facilitates the longitudinal growth of the internodes in monocots like sugarcane.
Therefore,even if the apical meristem (responsible for primary growth at the tip) is removed,the plant continues to grow in length due to the activity of the intercalary meristem.

(C) The longitudinal growth (increase in height) in a tree stem occurs primarily at the apical meristem located at the tips of the branches and the main trunk.
Since the nail is inserted into the mature,differentiated tissue below the apical meristem,this region does not undergo further vertical elongation.
Therefore,the nail will remain at the same height of $1$ metre from the ground level even after $3$ years of growth.

(D) Parenchyma is the simplest among simple permanent tissues.
The cells of parenchyma are generally isodiametric,thin-walled,and relatively unspecified,meaning they retain the ability to divide and perform various functions like storage,photosynthesis,and secretion.

(A) Collenchyma is a type of permanent tissue that provides both mechanical support and flexibility to plant parts like young stems and petioles.
This flexibility is possible because of the uneven thickening of cell walls at the corners due to the deposition of cellulose,hemicellulose,and pectin.

(B) Cork cells are the outer protective tissues of older stems and roots.
As these cells mature,they develop a waxy substance in their cell walls known as suberin.
Suberin makes these cells impervious to water and gases,thereby preventing water loss and protecting the plant from mechanical injury and pathogens.

(C) The survival of plants in terrestrial environments is primarily due to the presence of conducting tissues,specifically $Xylem$ and $Phloem$.
$Xylem$ is responsible for the conduction of water and minerals from the soil to the aerial parts of the plant,which is essential for survival in environments where water is not directly available to all plant parts.
$Phloem$ transports food synthesized in the leaves to other parts of the plant.
Therefore,conducting tissues allow plants to overcome the challenge of water scarcity and nutrient distribution in terrestrial habitats.

(A) Epithelial tissues do not have intercellular spaces between them. Instead,the cells are tightly packed together to form a continuous sheet with very little intercellular material.

(B) The primary water-conducting elements in gymnosperms are tracheids.
$1$. Sieve tubes are components of the phloem and are involved in the transport of food,not water.
$2$. Xylem fibres provide mechanical support and structural rigidity to the plant but do not participate in water conduction.
$3$. Vessels are specialized water-conducting structures that are typically absent in most gymnosperms (except for the Gnetales order).
$4$. Therefore,tracheids are the main water-conducting tissue in gymnosperms.

(N/A) The subcutaneous fat layer acts as an insulator for the body.
It prevents the loss of body heat to the cold environment.
This process is essential for thermoregulation,helping these animals maintain a constant body temperature despite the freezing external conditions.

(D) The correct matches are as follows:
$(a)$ Fluid connective tissue is Blood $(v)$.
$(b)$ Filling of space inside the organs is Areolar tissue $(iv)$.
$(c)$ Striated muscle is Skeletal muscle $(iii)$.
$(d)$ Adipose tissue is found in the Subcutaneous layer $(i)$.
$(e)$ Surface of joints is covered by Cartilage $(ii)$.
$(f)$ Stratified squamous epithelium is found in the Skin $(vi)$.
Thus, the correct sequence is $a-(v), b-(iv), c-(iii), d-(i), e-(ii), f-(vi)$.

(A) The correct matches are as follows:
$(a)$ Parenchyma: $(i)$ Thin-walled,packing cells. Parenchyma cells are simple,living,and thin-walled,serving as packing tissue.
$(b)$ Photosynthesis: $(ii)$ Carbon fixation. Photosynthesis is the process by which plants fix atmospheric carbon dioxide into organic compounds.
$(c)$ Aerenchyma: $(iv)$ Buoyancy. Aerenchyma is a modified parenchyma tissue with large air cavities that provide buoyancy to aquatic plants.
$(d)$ Collenchyma: $(iii)$ Localized thickenings. Collenchyma cells are characterized by uneven cell wall thickenings,primarily at the corners,due to cellulose and pectin deposition.
$(e)$ Permanent tissue: $(v)$ Sclerenchyma. Sclerenchyma is a type of permanent tissue that provides mechanical strength to plants.
Therefore,the correct sequence is $a-(i), b-(ii), c-(iv), d-(iii), e-(v)$.

(N/A) Transpiration is the process by which plants lose water in the form of water vapour through the stomata present on their leaves. When a potted plant is covered with a glass jar,the water vapour released during transpiration gets trapped inside the jar. As this water vapour comes into contact with the cooler surface of the glass jar,it undergoes condensation and forms fine water droplets on the inner walls of the jar.

(N/A) The xylem tissue is composed of four main types of elements:
$1$. Tracheids
$2$. Vessels
$3$. Xylem parenchyma
$4$. Xylem fibres
Among these,xylem parenchyma is the only living component of the xylem tissue,while the others (tracheids,vessels,and xylem fibres) are dead at maturity. The diagram of xylem parenchyma is provided below.

(N/A) Phloem is a complex permanent tissue that transports food in plants. It is composed of four main types of elements:
$1$. Sieve tubes: These are tubular cells with perforated walls (sieve plates) that facilitate the transport of food.
$2$. Companion cells: These are specialized parenchyma cells that assist the sieve tubes in their functions.
$3$. Phloem parenchyma: These are living cells that store food and provide structural support.
$4$. Phloem fibres: These are dead,thick-walled sclerenchyma cells that provide mechanical strength to the plant.

(A-D) $(a) - T$: Epithelial tissue forms the outer covering and protective layers of the body.
$(b) - T$: These structures are lined by simple squamous or cuboidal epithelium for exchange and secretion.
$(c) - F$: Epithelial cells are tightly packed with almost no intercellular spaces.
$(d) - T$: The epithelial layer is permeable,allowing the exchange of substances.
$(e) - F$: The epithelial layer plays a crucial role in regulating the exchange of materials between the body and the external environment.

(N/A)

Voluntary muscles	Involuntary muscles
$(i)$ Their action is under our conscious control.	$(i)$ Their action is not under our conscious control.
$(ii)$ These are typically striated and multinucleate.	$(ii)$ These are typically non-striated and uninucleate.
$(iii)$ Example: Skeletal muscles (e.g.,biceps).	$(iii)$ Example: Smooth muscles (e.g.,muscles in the digestive tract).

(A) The classification of activities based on muscle type is as follows:
$(a)$ Jumping of a frog: This involves skeletal muscles which are under conscious control,hence it is Voluntary $(V)$.
$(b)$ Pumping of the heart: This is controlled by cardiac muscles which function automatically without conscious effort,hence it is Involuntary $(IV)$.
$(c)$ Writing with hand: This involves skeletal muscles controlled by the brain's conscious command,hence it is Voluntary $(V)$.
$(d)$ Movement of food in your intestine: This involves smooth muscles which perform peristalsis automatically,hence it is Involuntary $(IV)$.
Final Answer: $(a)-V, (b)-IV, (c)-V, (d)-IV$.

(N/A) The lining of blood vessels is made up of squamous epithelium,which allows for the easy transport of substances through diffusion.
$(b)$ The lining of the small intestine is made up of columnar epithelium,which facilitates absorption and secretion.
$(c)$ The lining of kidney tubules is made up of cuboidal epithelium,which provides mechanical support and helps in absorption and secretion.
$(d)$ Epithelial cells with cilia are found in the respiratory tract,where they help in moving mucus out of the airways.

(N/A) Water hyacinth contains a specialized type of parenchyma tissue known as $Aerenchyma$.
This tissue is characterized by the presence of large air-filled cavities or intercellular spaces.
These air spaces provide buoyancy to the plant,which allows the water hyacinth to float on the surface of the water.

(B) The $Epidermis$ is the outermost protective layer of the plant body.
It is often covered by a thick, waxy, and water-resistant layer called the $Cuticle$.
This $Cuticle$ acts as a physical barrier that prevents the entry of pathogens, parasites, and excessive water loss, thereby protecting the plant.

(A) Suberin: It is a waxy substance deposited in the cell walls of cork cells,making them impermeable to water and gases.
$(b)$ Sieve tubes: These are components of the phloem tissue,consisting of living tubular cells with perforated end walls (sieve plates).
$(c)$ Calcium and phosphorus: The matrix of bone is rich in calcium and phosphorus salts,which provide strength and rigidity to the skeletal system.

(C) The epidermis is important for plants due to the following reasons:
$(i)$ It provides protection to the underlying tissues against mechanical injury and pathogen invasion.
$(ii)$ It helps in gaseous exchange through specialized structures called stomata.
$(iii)$ It checks excessive water loss through the process of transpiration by forming a waxy cuticle layer.
$(iv)$ Root hairs arising from the epidermal cells increase the surface area for the absorption of water and minerals from the soil.

(N/A) Xylem and phloem are complex tissues.
$(b)$ Stomata have guard cells.
$(c)$ Cells of cork contain a chemical called Suberin.
$(d)$ Husk of coconut is made of Sclerenchyma tissue.
$(e)$ Collenchyma gives flexibility in plants.
$(f)$ Xylem and phloem are both conducting tissues.
$(g)$ Xylem transports water and minerals from soil.
$(h)$ Phloem transports food from leaves to other parts of the plant.

(N/A) The differences between parenchyma and sclerenchyma tissues are as follows:

Parenchyma	Sclerenchyma
$(1)$ Cells are thin-walled and unspecialized.	$(1)$ Cells are thick-walled and lignified.
$(2)$ These are living cells.	$(2)$ These are dead cells.
$(3)$ Cells are usually loosely packed with large intercellular spaces.	$(3)$ No intercellular spaces are found between the cells.
$(4)$ Stores nutrients and water in stems and roots.	$(4)$ Provides mechanical strength to plant parts.
$(5)$ Some cells contain chlorophyll (chlorenchyma) and perform photosynthesis. Others have large air cavities (aerenchyma) providing buoyancy to aquatic plants.	$(5)$ Cells are long and narrow,making the plant hard and stiff. Found in stems,around vascular bundles,in leaf veins,and the hard covering of seeds and nuts.

[Diagrams: Refer to the provided images showing $T$.$S$. and $L$.$S$. of both tissues.]

(N/A) Epithelial tissues are the covering or protective tissues in the animal body. Epithelium covers most organs and cavities within the body and keeps different body systems separate. The skin,the lining of the mouth,the lining of blood vessels,lung alveoli,and kidney tubules are all made of epithelial tissue.
Epithelial tissue cells are tightly packed and form a continuous sheet. They have only a small amount of cementing material between them and almost no intercellular spaces. The permeability of the cells of various epithelia plays an important role in regulating the exchange of materials between the body and the external environment and also between different parts of the body. Regardless of the type,all epithelia are usually separated from the underlying tissue by an extracellular fibrous basement membrane.
Epithelial tissues are of the following types:
$(1)$ Simple squamous epithelium: Extremely thin and flat,forming a delicate lining. Found in blood vessels and lung alveoli where transportation occurs.
$(2)$ Stratified squamous epithelium: Arranged in many layers to prevent wear and tear. Found in the skin and lining of the mouth.
$(3)$ Columnar epithelium: Tall epithelial cells present where absorption and secretion occur,such as the inner lining of the intestine. If they have cilia,they are called ciliated columnar epithelium,which helps in moving mucus.
$(4)$ Cuboidal epithelium: Cube-shaped cells forming the lining of kidney tubules and ducts of salivary glands,providing mechanical support.
Additionally,some epithelial tissue folds inward to form a multicellular gland,known as glandular epithelium.