Mix Example - TISSUES Questions in English

(N/A) The three main types of muscles found in the human body are as follows:
$1$. Striated Muscles (Skeletal Muscles): These are cylindrical,unbranched,and multinucleated. They show alternate light and dark bands (striations) and are attached to bones.
$2$. Smooth Muscles (Unstriated Muscles): These are spindle-shaped (fusiform) with a single central nucleus. They do not show striations and are found in the walls of internal organs like the stomach and intestines.
$3$. Cardiac Muscles: These are cylindrical,branched,and uninucleated. They show striations and are involuntary muscles found exclusively in the heart.
(Please refer to the provided image for the diagrams of these muscle types.)

(N/A) Meristematic cells are actively dividing cells. $A$ prominent nucleus and dense cytoplasm are required to support rapid metabolic activity and cell division. Vacuoles are absent because these cells do not need to store food or maintain turgidity for structural support.
$(b)$ Sclerenchymatous cells have thick,lignified cell walls that are tightly packed together,leaving no intercellular spaces.
$(c)$ Pear fruit contains specialized sclerenchyma cells known as stone cells or sclereids,which provide a gritty and granular texture.
$(d)$ Collenchyma tissue is present in the stalks and branches of plants. It provides both structural support and flexibility,allowing branches to bend without breaking in high wind.
$(e)$ The husk of a coconut is made of sclerenchyma tissue,which is dead and heavily lignified,making it extremely hard and tough to remove.

(N/A) Characteristics:
- The cells of cork are dead at maturity.
- These cells are compactly arranged without any intercellular spaces.
- The cell walls possess a chemical substance called $suberin$, which makes them impervious to gases and water.
- They are several layers thick.
Formation:
- As plants grow older, the epidermis of the stem is replaced by a strip of secondary meristem known as the $phellogen$ or cork cambium.
- The cells cut off on the outer side by this meristem differentiate into cork cells.
Role:
- Cork acts as a protective tissue for older stems, twigs, and branches.
- It prevents water loss and protects the plant from mechanical injury and microbial infection.

(N/A) Xylem and phloem are called complex tissues because they are made up of more than one type of cells that work together as a unit to perform a common function.

Xylem	Phloem
Consists of tracheids,vessels,xylem parenchyma,and xylem fibres.	Consists of sieve tubes,companion cells,phloem parenchyma,and phloem fibres.
Transports water and minerals vertically from the soil to the aerial parts of the plant.	Transports food (photosynthates) from the leaves to other parts of the plant.
Most of the cells,except xylem parenchyma,are dead at maturity.	Most of the cells,except phloem fibres,are living at maturity.

(N/A)

Meristematic Tissue	Permanent Tissue
Cells of this tissue divide throughout their life.	They lose the ability to divide to take up specific functions.
They are located at specific regions of the plant,viz.,apical,lateral,and intercalary.	They are distributed throughout the plant body.
Cells are very active,have dense cytoplasm,thin walls,and prominent nuclei. They lack vacuoles.	They are vacuolated,vary in shape and size. Their cell wall may be thick.
Cell wall is cellulosic.	Cell wall is made up of cellulose,lignin,or suberin.

$(b)$ The process by which cells derived from meristematic tissue take up a permanent shape,size,and function and lose the ability to divide is called differentiation.
$(c)$ Simple permanent tissues: Parenchyma,Collenchyma (any two).
Complex permanent tissues: Xylem,Phloem.

(N/A) The cells that make up meristematic tissue have dense cytoplasm,thin cellulose cell walls,and prominent nuclei. Additionally,they lack vacuoles.

(C) Lateral meristem is the type of meristematic tissue that is responsible for the secondary growth in plants.
It increases the girth or diameter of the stem and root.
This tissue is commonly referred to as cambium.

(C) The muscular tissue whose cells are spindle-shaped and uninucleate is known as $Smooth$ $muscle$ (also called $Unstriated$ $muscle$ or $Involuntary$ $muscle$).
These cells are long with pointed ends (spindle-shaped) and contain a single central nucleus (uninucleate).
They are found in the walls of internal organs such as the stomach, intestines, and blood vessels.

(N/A) The solid matrix of cartilage is composed of proteins and sugars. These components are primarily organized as proteoglycans,which provide the tissue with its characteristic flexibility and strength.

(B) Adipose tissue is a type of connective tissue that stores fat. It is found below the skin and between internal organs. Due to the presence of fat,it acts as an insulator and prevents the loss of heat from the body,thereby helping to maintain body temperature.

(D) The veins of leaves contain vascular tissues known as $Xylem$ and $Phloem$. $Xylem$ is responsible for the conduction of water and minerals,while $Phloem$ is responsible for the translocation of food. Additionally,$Sclerenchyma$ fibers are often present around the vascular bundles to provide mechanical support.

(B) The cells present at the growing tips of roots and stems are called meristematic cells (or meristem).
These cells have the ability to divide continuously,which leads to the growth of the plant in length.
This specific type of meristem is known as apical meristem.

(B) ligament is a specialized type of connective tissue that connects bone to bone. It is highly elastic and provides stability to joints.

(A) The tissue in which food is stored in plants is known as $Parenchyma$.
$Parenchyma$ is a type of simple permanent tissue that acts as a packing tissue and provides support to plants.
Specifically,when $Parenchyma$ contains chlorophyll and performs photosynthesis,it is called $Chlorenchyma$,and when it stores food and water,it serves as a storage tissue.

(N/A) Vascular bundles are complex tissues found in plants that consist of two primary conducting tissues: xylem and phloem.
Xylem is responsible for the transport of water and dissolved minerals from the roots to the rest of the plant.
Phloem is responsible for the transport of food (sugars) synthesized during photosynthesis from the leaves to other parts of the plant.
Together,these tissues form a structural unit known as a vascular bundle,which is essential for the transport system in vascular plants.

(C) $WBC$ (White Blood Cells),also known as leukocytes,are an essential part of the immune system.
Their primary function is to defend the body against pathogens such as bacteria,viruses,and other foreign substances.
They achieve this by engulfing foreign particles or by producing antibodies,thereby providing immunity to the body.

(B) $RBCs$ (Red Blood Cells) contain a respiratory pigment called haemoglobin.
Haemoglobin binds with $O_{2}$ to form oxyhaemoglobin,which facilitates the transport of oxygen from the lungs to the body tissues.
It also plays a role in the transport of $CO_{2}$ from the tissues back to the lungs for exhalation.

(C) Blood platelets,also known as thrombocytes,are cell fragments derived from megakaryocytes in the bone marrow.
They play a crucial role in the process of blood clotting (coagulation) at the site of an injury to prevent excessive blood loss.

(N/A) Stomata are microscopic apertures or pores primarily found on the epidermis of leaves. They are surrounded by two specialized cells known as guard cells. Their main functions include the exchange of gases ($CO_2$ and $O_2$) between the plant and the atmosphere and the process of transpiration,which is the loss of water vapor from the plant surface.

(B) Skeletal muscles are known as striated muscles because,when observed under a microscope,they exhibit a characteristic pattern of alternate light and dark bands or striations when stained appropriately. These bands are caused by the regular arrangement of contractile proteins,specifically actin and myosin,within the muscle fibers. Consequently,they are referred to as striated muscles.

(N/A) Tracheids and vessels are the main conducting elements of the xylem tissue in plants.
Their tubular structure provides a low-resistance pathway for the bulk flow of water and dissolved minerals from the roots to the leaves.
This vertical,pipe-like arrangement allows for efficient long-distance transport against gravity,which is essential for the survival of vascular plants.

(N/A) Location: Collenchyma is found in the leaf stalks (petioles) and below the epidermis of dicot stems.
Function: It provides mechanical support and flexibility to the plant,allowing parts like leaf stalks to bend easily without breaking.

(B) The connective tissue found between the skin and muscles is known as areolar connective tissue. It acts as a supporting and packing tissue between organs and fills the space inside the organs,supporting internal organs and helping in the repair of tissues.

(C) The meristem responsible for the increase in the girth (diameter) of the stem and root is known as the $Lateral$ $meristem$ (also called $Cambium$).
It is a secondary meristem that adds to the thickness of the plant body.

(N/A) $(i)$ Aerenchyma: This is a type of parenchyma tissue containing large air cavities that provide buoyancy to aquatic plants,allowing them to float.
$(ii)$ Collenchyma: This is a mechanical tissue that provides structural support and flexibility to the plant,allowing easy bending without breaking.

(N/A) The two types of complex tissues in plants are $Xylem$ and $Phloem$.
$Xylem$ is responsible for the conduction of water and minerals from the roots to the leaves.
$Phloem$ is responsible for the translocation of food (photosynthates) from the leaves to other parts of the plant.

(A) Simple squamous epithelial tissue consists of a single layer of extremely thin and flat cells,forming a delicate lining,such as in the blood vessels or lung alveoli.
Stratified squamous epithelial tissue consists of cells arranged in many layers to prevent wear and tear.
This multi-layered arrangement is specifically found in areas subjected to mechanical stress,such as the skin,the lining of the mouth,and the oesophagus.

(N/A) The muscular tissue present in the iris of the eye is the $Smooth$ muscle (also known as involuntary muscle).
These cells are $spindle-shaped$ (fusiform), meaning they are wide in the middle and tapered at both ends.

(N/A) $1$. Unstriated muscle fibres are found in the walls of the alimentary canal,iris of the eye,ureters,and bronchi.
$2$. Cuboidal epithelium is found in the lining of kidney tubules and ducts of salivary glands.
$3$. Adipose tissue is found below the skin and between internal organs.
$4$. Striated muscle fibres are found in the limbs,tongue,and body wall.

(N/A) $(i)$ In very dry habitats,the epidermis is often thicker to provide protection against water loss. Additionally,the aerial parts of these plants often secrete a waxy,water-resistant layer (cuticle) on the outer surface to protect against water loss,mechanical injury,and invasion by parasitic fungi.
$(ii)$ The primary functions of guard cells are:
$1.$ To regulate the opening and closing of stomata.
$2.$ To facilitate the exchange of gases (like $CO_2$ and $O_2$) between the plant and the atmosphere.
$3.$ To control transpiration by regulating water vapor loss.

(N/A) The nervous tissue is primarily found in the following parts of the body:
$(i)$ Brain
$(ii)$ Spinal cord
$(iii)$ Nerves
The cells that make up the nervous tissue are called neurons (or nerve cells).

(N/A) Connective tissue is called so because its primary function is to bind,support,and connect different tissues and organs of the body together.
$(b)$ Areolar connective tissue fills the space inside the organs,supports internal organs,and helps in the repair of tissues.
$(c)$ Adipocytes contain fat globules. This stored fat acts as an insulator against heat loss and provides energy to the body.

(N/A)

Xylem	Phloem
$(i)$ It conducts water and minerals from roots to all parts of the plant.	$(i)$ It conducts organic food synthesized in the leaves and hormones synthesized at the shoot and root tips to other parts of the plant.
$(ii)$ The elements which help in conduction are tracheids and vessels. Both are non-living and have thick walls.	$(ii)$ Sieve-tube cells are responsible for the movement of material through phloem. They are living cells.
$(iii)$ The material in xylem moves only in one direction (unidirectional).	$(iii)$ The material in phloem can move in both directions (bidirectional).
$(iv)$ Except for xylem parenchyma,all other xylem elements are non-living.	$(iv)$ Except for phloem fibres,all other phloem elements are living.

(N/A)

Sclerenchyma	Collenchyma
$1$. It consists of dead cells.	$1$. It consists of living cells.
$2$. Its cell walls are lignified.	$2$. Its cell walls are cellulosic.
$3$. Lumen of the cell is narrow.	$3$. Lumen of the cell is wide.
$4$. It provides mechanical support to the plant.	$4$. It provides mechanical support and elasticity to the plant body.

(N/A) Features of cardiac muscles are:
$(i)$ These are involuntary muscles that exhibit rhythmic contraction and relaxation throughout life.
$(ii)$ These muscles are composed of non-tapering cells with faint cross-striations.
$(iii)$ The cells of these muscles are cylindrical,branched,and uninucleate.
$(iv)$ These muscles do not get fatigued under normal conditions.

(N/A) $(i)$ Tracheids and vessels are the main conducting elements that help in the transport of water and minerals.
(ii) Xylem parenchyma is the only living component of xylem that stores food materials in the form of starch or fat.
(iii) Xylem fibres (also known as xylem sclerenchyma) are dead cells with thick walls that provide mechanical support to the plant.

(N/A) $(1)$ Cells divide repeatedly.
$(2)$ Cell walls are thin and made of cellulose.
$(3)$ Vacuoles are either absent or very small.
$(4)$ They are metabolically very active.
$(5)$ They possess dense cytoplasm.
$(6)$ They have a prominent and large nucleus.

(N/A) The two main components of blood are plasma and blood cells (corpuscles).
Blood is considered a type of connective tissue because it consists of a fluid matrix,known as plasma,in which various blood cells are suspended. Connective tissues are defined by having cells embedded in an extracellular matrix,and blood fits this definition as the plasma acts as the matrix connecting different parts of the body by transporting nutrients,gases,and waste products.

(N/A) The chemical substance that makes the cell walls of sclerenchyma hard is $Lignin$. This substance acts as a cement and hardens the cell wall.
Sclerenchyma tissue is typically found in the following locations:
$1$. Around vascular bundles.
$2$. In the veins of leaves.
$3$. In the hard covering of seeds and nuts (e.g.,the shell of a coconut).

(N/A) The liquid matrix of the blood is called $Plasma$.
$Plasma$ contains water,proteins (such as $albumin$,$globulin$,and $fibrinogen$),salts (electrolytes),hormones,glucose,and waste products.
Two functions of blood are:
$1$. It transports respiratory gases ($O_2$ and $CO_2$) between the lungs and body tissues.
$2$. It transports digested food,hormones,and waste materials to different parts of the body.

(N/A)

Striated Muscles	Unstriated Muscles
$1.$ The cells are long,cylindrical,unbranched,and multinucleate.	$1.$ The cells are long,spindle-shaped (pointed at both ends),and uninucleate.
$2.$ These are mostly attached to bones and help in voluntary body movements.	$2.$ These are present in the walls of the alimentary canal,blood vessels,iris of the eye,ureters,and bronchi.

(N/A) Areolar tissue fills the space inside the organs,supports internal organs,and helps in the repair of tissues. (Any $1$)
$(b)$ Cuboidal epithelium provides mechanical support and is involved in secretion and absorption.

(N/A) It provides mechanical support to plants.
$(b)$ It stores food materials like starch,proteins,and fats.
$(c)$ In aquatic plants,parenchyma cells contain large air cavities (aerenchyma) which provide buoyancy and help the plant float.

(D) Chlorenchyma: These are specialized parenchyma cells that contain chlorophyll and are primarily responsible for performing photosynthesis.
Aerenchyma: These are specialized parenchyma cells found in aquatic plants that contain large air cavities. These cavities help the plants to float (buoyancy) and facilitate gas exchange.

(N/A) The tissue that transmits stimuli in our body is the nervous tissue.
$(b)$ Nervous tissue contains specialized cells called neurons that receive and transmit electrical impulses. When a stimulus is received,the nervous tissue sends a signal to the muscle tissue. The muscle tissue then contracts or relaxes in response to these signals,which allows animals to move rapidly.

(N/A) The two basic structural differences are as follows:
$1$. Cell Wall: Parenchyma cells have thin cell walls made of cellulose,whereas collenchyma cells have unevenly thickened cell walls due to the deposition of cellulose,hemicellulose,and pectin at the corners.
$2$. Intercellular Spaces: Parenchyma cells are loosely packed with large intercellular spaces,whereas collenchyma cells are closely packed with very little or no intercellular space.

(N/A) Tissue $A$ is Adipose tissue.
Reason: It is a type of connective tissue where cells are specialized to store fats in the form of globules. This fat layer acts as an insulator against heat loss from the body.
Tissue $B$ is Cardiac muscle.
Reason: Cardiac muscle cells are cylindrical,branched,and uninucleate. They are involuntary muscles that exhibit rhythmic contraction and relaxation throughout the life of an organism to pump blood.

(N/A) These muscles are called skeletal muscles because they are primarily attached to the bones of the skeleton and facilitate body movement.
$(b)$ Two structural characteristics are:
$(i)$ They exhibit alternating light and dark bands (striations) under a microscope.
$(ii)$ They are multinucleated (contain many nuclei) and the cells are cylindrical and unbranched.

(N/A) Areolar tissue: It is a loose connective tissue that acts as a supporting and packing tissue between the skin and muscles.
$(b)$ Ligament: It is a fibrous connective tissue that connects two bones together.
$(c)$ Cuboidal epithelium: This tissue consists of cube-shaped cells and is found in the lining of kidney tubules and ducts of salivary glands,providing mechanical support.
$(d)$ Sclerenchyma: This is a permanent plant tissue composed of dead cells with thick lignified walls,providing structural strength to the veins of leaves.

(N/A) Tendons: These are fibrous connective tissues that attach skeletal muscle to bone.
$(b)$ Squamous epithelium: Specifically,simple squamous epithelium forms the delicate inner lining of the alveoli in the lungs to facilitate gas exchange.
$(c)$ Adipose tissue: This is a specialized connective tissue that stores fat in the form of fat globules.
$(d)$ Xylem: This is a complex permanent tissue in plants responsible for the conduction of water and dissolved minerals from the roots to the rest of the plant.