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NCERT Exemplar Class 9 Science Chapter 6 Tissues Solutions

NCERT Exemplar Solutions for Class 9 Science Chapter 6 Tissues covers all the important questions and answers as well as advanced level questions. It helps in learning about the functions of tissues, animal tissues like epithelial tissue, connective tissue, muscular and nervous tissue, meristematic plant tissues, role of tissues in plants, permanent tissues like simple tissues and complex tissues.

The NCERT Exemplar solutions for class 9 science is very important in the examination. NCERT Exemplar Solutions for Class 9 Science Chapter 6 Tissues is provided by our experts. They prepared the best solutions which help the students in understanding the solutions in an easy way. This chapters also covers the other topics like meristematic tissue is the only dividing tissue, simple tissues like  parenchyma, collenchyma and sclerenchyma, complex tissues like xylem and phloem, types of epithelial tissue, connective tissues like areolar tissue, adipose tissue, bone, tendon, cartilage and blood and muscular tissues like striated, striated and cardiac.


Chapter Name

Chapter 6 Tissues

Book Title

NCERT Exemplar for Class 9 Science

Related Study

  • NCERT Solutions for Class 9 Science Chapter 6 Tissues
  • Revision Notes for Class 9 Science Chapter 6 Tissues
  • MCQ for Class 9 Science Chapter 6 Tissues
  • Important Questions for Class 9 Science Chapter 6 Tissues

Topics Covered

  • MCQ
  • Short Answers Questions
  • Long Answers Questions

NCERT Exemplar Solutions for Chapter 6 Tissues Class 9 Science

Multiple Choice Questions

1. Which of the following tissues has dead cells?
(a) Parenchyma
(b) Sclerenchyma
(c) Collenchyma
(d) Epithelial tissue

Solution

(b) Sclerenchyma

Sclerenchyma is composed of dead cells which have thick cell wall due to deposition of lignin. They are generally located in the leaf veins, hard coverings of the seeds and can also be found surrounding the vascular bundle.


2. Find out incorrect sentence :
(a) Parenchymatous tissues have intercellular spaces.
(b) Collenchymatous tissues are irregularly thickened at corners.
(c) Apical and intercalary meristems are permanent tissues.
(d) Meristematic tissues, in its early stage, lack vacuoles.

Solution

(c) Apical and intercalary meristems are permanent tissues.

Apical and intercalary meristems are not permanent tissues but they are meristematic tissues which remain in continuous state of division. These tissues differentiate to give rise to the permanent tissues.


3. Girth of stem increases due to :
(a) apical meristem
(b) lateral meristem
(c) intercalary meristem
(d) vertical meristem

Solution

(b) lateral meristem

Lateral meristem occurs on the sides almost parallel to the long axis of the root, stem and its branches. It is responsible for an increase in girth of the stem, i.e. secondary growth.


4. Which cell does not have perforated cell wall?
(a) Tracheids
(b) Companion cells
(c) Sieve tubes
(d) Vessels

Solution

(b) Companion cells


5. Intestine absorb the digested food materials. What type of epithelial cells are responsible for that?
(a) Stratified squamous epithelium
(b) Columnar epithelium
(c) Spindle fibres
(d) Cuboidal epithelium

Solution

(b) Columnar epithelium

Columnar epithelium is pillar-like cell which have nuclei towards its base. They form the lining of stomach, small intestine and colon, forming the mucous membrane. They also the facilitate movement across the epithelial barrier. Their main function is absorption and secretion.


6. A person met with an accident in which two long bones of hand were dislocated. Which among the following may be the possible reason?
(a) Tendon break
(b) Break of skeletal muscle
(c) Ligament break
(d) Areolar tissue break

Solution

(c) Ligament break

When joints held by ligaments get separated dislocation of bones occur. Tendons join the skeletal muscle and they cause inflammation upon break.


7. While doing work and running, you move your organs like hands, legs, etc. Which among the following is correct?
(a) Smooth muscles contract and pull the ligament to move the bones.
(b) Smooth muscles contract and pull the tendons to move the bones.
(c) Skeletal muscles contract and pull the ligament to move the bones.
(d) Skeletal muscles contract and pull the tendon to move the bones.

Solution

(d) Skeletal muscles contract and pull the tendon to move the bones.

Skeletal muscles contract and they pull the tendon, connecting muscles to bones while doing work and running. This moves the bones and they do not pull the ligaments as that will cause a sprain or stretch.


8. Which muscles act involuntarily?
(i) Striated muscles
(ii) Smooth muscles
(iii) Cardiac muscles
(iv) Skeletal muscles
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (i) and (iv)

Solution

(b) (ii) and (iii)

Skeletal muscles are voluntary muscles which are also striated muscles.


9. Meristematic tissues in plants are :
(a) localised and permanent
(b) not limited to certain regions
(c) localised and dividing cells
(d) growing in volume

Solution

(c) localised and dividing cells

Meristematic tissues in plants are the dividing cells. They are responsible for plant growth in certain specific region. Based on the location, meristematic tissues are classified as apical, lateral and intercalary.


10. Which is not a function of epidermis?
(a) Protection from adverse condition
(b) Gaseous exchange
(c) Conduction of water
(d) Transpiration

Solution

(c) Conduction of water

Conduction of water is a function of xylem tissue whereas protection, gaseous exchange and transpiration are the function of epidermis.


11. Select the incorrect sentence :

(a) Blood has matrix containing proteins, salts’ and hormones.
(b) Two bones are connected with ligament.
(c) Tendons are non-fibrous tissue and fragile.
(d) Cartilage is a form of connective tissue.

Solution

(c) Tendons are non-fibrous tissue and fragile.

Tendons are fibrous tissues which are highly elastic and strong.


12. Cartilage is not found in :
(a) nose
(b) ear
(c) kidney
(d) larynx

Solution

(c) kidney

Cartilage is a connective tissue which provides support and flexibility to various parts of our body. Cartilage is found in nose, ear, larynx but not in kidney.


13. Fats are stored in human body as :
(a) cuboidal epithelium
(b) adipose tissue
(c) bones
(d) cartilage

Solution

(b) adipose tissue

Fat is stored in the adipose tissue present below the skin and between internal organs. Cells in these tissues are filled with fat globules.


14. Bone matrix is rich in :
(a) fluoride and calcium
(b) calcium and phosphorus
(c) calcium and potassium
(d) phosphorus and potassium

Solution

(b) calcium and phosphorus


15. Contractile proteins are found in :
(a) bones
(b) blood
(c) muscles
(d) cartilage

Solution

(c) muscles

Contractile proteins are responsible for the contraction and relaxation of muscles.


16. Voluntary muscles are found in :
(a) alimentary canal
(b) limbs
(c) iris of the eye
(d) bronchi of lungs

Solution

(b) limbs

Some muscles can be moved by our own will. Muscles present in our limbs can move at our will, and stop when we decide to. Such muscles are called voluntary muscles.


17. Nervous tissue is not found in :
(a) brain
(b) spinal cord
(c) tendons
(d) nerves

Solution

(c) tendons

Tendons are the connective tissue which connects muscles to bones. They are fibrous in nature and gives strength and limited flexibility.


18. Nerve cell does not contain :
(a) axon
(b) nerve endings
(c) tendons
(d) dendrites

Solution

(c) tendons

Neurons are connective tissues that join skeletal muscles to bones, so they do not contain tendons.


19. Which of the following helps in repair of tissue and fills up the space inside the organ?
(a) Tendon
(b) Adipose tissue
(c) Areolar
(d) Cartilage

Solution

(c) Areolar

Areolar connective tissue is found between the skin and muscles, around blood vessels and nerves and in the bone marrow. It fills the space inside the organs, supports internal organs and helps in repair of tissues.


20. The muscular tissue which function throughout the life continuously without fatigue is :
(a) skeletal muscle
(b) cardiac muscle
(c) smooth muscle
(d) voluntary muscle

Solution

(b) cardiac muscle

Heart muscles are cylindrical, branched and uninucleated. They show rhythmic contraction and relaxation throughout life. Skeletal muscle, smooth muscle and voluntary muscles work as and when required.


21. Which of the following cells is found in the cartilaginous
tissue of the body?
(a) Mast cells
(b) Basophils
(c) Osteocytes
(d) Chondrocytes

Solution

(d) Chondrocytes

Mast cells are found in areolar tissue. Basophils are found in blood. Osteocytes are found in bone.


22. The dead element present in the phloem is :
(a) companion cells
(b) phloem fibres
(c) phloem parenchyma
(d) sieve tubes

Solution

(b) phloem fibres

Phloem fibres possess narrow lumen and thick-walls. They are elongated spindle-shaped dead cell. It provides mechanical support to the tissue. Phloem parenchyma is the thin-walled living cells of parenchyma.


23. Which of the following does not lose their nucleus at maturity?
(a) Companion cells
(b) Red blood cells
(c) Vessel
(d) Sieve tube cells

Solution

(a) Companion cells


24. In desert plants, rate of water loss gets reduced due to the presence of :
(a) cuticle
(b) stomata
(c) lignin
(d) suberin

Solution

(a) cuticle

Cuticle is a protective layer covering epidermis of the leaf, young shoots and other aerial parts of a plant. Cuticle minimizes the effect of heat and reduces the loss of water as it contains lipids and polymers impregnated with wax.


25. A long tree has several branches. The tissue that helps in the sideways conduction of water in the branches is :
(a) collenchyma
(b) xylem parenchyma
(c) parenchyma
(d) xylem vessels

Solution

(d) xylem vessels

Collenchyma is an active tissue and has no role in the conduction of water. Parenchyma is a supportive tissue. Xylem vessels also known as xylem trachea are responsible for conduction of water in plants.


26. If the tip of sugarcane plant is removed from the field, even then it keeps on growing in length. It is due to the presence of :
(a) cambium
(b) apical meristem
(c) lateral meristem
(d) intercalary meristem

Solution

(d) intercalary meristem

Intercalary meristem is responsible for the longitudinal growth of the plant even in the absence of apical meristem.


27. A nail is inserted in the trunk of a tree at a height of 1 metre from the ground level. After 3 years the nail will :
(a) move downwards
(b) move upwards
(c) remain at the same position
(d) move sideways

Solution

(c) remain at the same position

Longitudinal growth in the stem always takes place on the top. The apical meristem in the lower region remains constant. This is the reason why there will be no change in position of nail inserted in the trunk of the tree.


28. Parenchyma cells are :
(a) relatively unspecified and thin walled
(b) thick walled and specialised
(c) lignified
(d) None of these

Solution

(a) relatively unspecified and thin walled

The most common simple permanent tissue is the parenchyma. It consists of relatively unspecialized cells with thin cell walls. They are living cells. They are usually loosely arranged, thus large spaces between cells (intercellular spaces) are found in this tissue.


29. Flexibility in plants is due to :
(a) collenchyma
(b) sclerenchyma
(c) parenchyma
(d) chlorenchyma

Solution

(a) collenchyma


30. Cork cells are made impervious to water and gases by the presence of :
(a) cellulose
(b) lipids
(c) suberin
(d) lignin

Solution

(c) suberin


31. Survival of plants in terrestrial environment has been made possible by the presence of :
(a) intercalary meristem
(b) conducting tissue
(c) apical meristem
(d) parenchymatous tissue

Solution

(b) conducting tissue

Xylem and phloem which are the conducting tissues are responsible for the survival of plants in terrestrial environment. Xylem conduct water from roots to all the parts of the plants and phloem transports food and other nutrients from leaves to other parts of the plant.


32. Choose the wrong statement.
(a) The nature of matrix differs according to the function of the tissue.
(b) Fats are stored below the skin and in between the internal organ
(c) Epithelial tissues have intercellular spaces between them.
(d) Cells of striated muscles are multinucleate and unbranched.

Solution

(c) Epithelial tissues have intercellular spaces between them.

Epithelial tissues do not have intercellular spaces between them. They are tightly bound together to make continuous sheet.


33. The water conducting tissue generally present in gymnosperm is :
(a) vessel
(b) sieve tube
(c) tracheids
(d) xylem fibres

Solution

(c) tracheids

Vessels are generally absent in gymnosperms. Sieve tubes are present in phloem. Xylem fibres provide structural rigidity and have no role in conduction of water.


Short Answer Questions

34. Why animals of colder regions and fishes of cold water have thicker layer of subcutaneous fat?

Solution

Animals of colder regions and fishes of cold water have thicker layer of subcutaneous fat. This acts as an insulator and prevents the escape of heat from their body.


35. Match the column (A) with the column (B).

 

Column (A)

 

Column (B)

(1)

Parenchyma

(1)

Thin walled, packing cells

(2)

Photosynthesis

(2)

Carbon fixation

(3)

Aerenchyma

(3)

Localized thickenings

(4)

Collenchyma

(4)

Buoyancy

(5)

Permanent tissue

(5)

Sclerenchyma

Solution

(A)

(B)

(a) Parenchyma

(i) Thin-walled, packing cells

(b) Photosynthesis

(ii) Carbon fixation

(c) Aerenchyma

(iv) Buoyancy

(d) Collenchyma

(iii) Localized thickenings

(e) Permanent tissue

(v) Sclerenchyma


36. Match the column (A) with the column (B).

(A)

(B)

(a) Fluid connective tissue

(i) Subcutaneous layer

(b) Filling of space inside the organs

(ii) Cartilage

(c) Striated muscle

(iii) Skeletal muscle

(d) Adipose tissue

(iv) Areolar tissue

(e) Surface of joints

(v) Blood

(f) Stratified squamous epithelium

(vi) Ski

Solution

(A)

(B)

(a) Fluid connective tissue

(v) Blood

(b) Filling of space inside the organs

(iv) Areolar tissue

(c) Striated muscle

(iii) Skeletal muscle

(d) Adipose tissue

(i) Subcutaneous layer

(e) Surface of joints

(ii) Cartilage

(f) Stratified squamous epithelium

(vi) Ski


37. If a potted plant is covered with a glass jar, water vapours appear on the wall of glass jar. Explain, why?

Solution

Water is released from the plants in the form of vapours because of the process called transpiration.


38. Name the different components of xylem and draw a living component.

Solution

The different components of xylem are:

  1. tracheids
  2. vessels
  3. xylem parenchyma
  4. xylem fibres.

The only living component of xylem is xylem parenchyma.


39. Draw and identify different elements of phloem.

Solution


40. Differentiate between voluntary and involuntary muscles. Give one example of each type.

Solution

Voluntary muscles

Involuntary muscles

They are also called striated muscles since they show stripes or striations.

They are also called non-striated muscles since they lack striations.

Their cells are long and cylindrical.

Their cells are small and spindle shaped.

They have multinucleate cells.

They have uninucleate cells.

They are under our will or control.

They are not under our will or control.

They get tired and need rest at intervals.

They can work continuously without getting tired.

Example: Limb muscles

Example: Cardiac muscles


41. Write true (T) or false (F) :
(a) Epithelial tissue is protective tissue in animal body.
(b) The lining of blood vessels, lung alveoli and kidney tubules are all made up of epithelial tissue.
(c) Epithelial cells have a lot of intercellular spaces.
(d) Epithelial layer is permeable layer.
(e) Epithelial layer does not allow regulation of materials between body and external environment.

(a) True,

(b) True

(c) False

(d) True

(e) False


42. Differentiate the following activities on the basis of voluntary or involuntary muscles :
(a) Jumping of frog
(b) Pumping of the heart
(c) Writing with hand
(d) Movement of chocolate in your intestine

Solution

(a) Jumping of frog is an activity of voluntary muscles.

(b) Pumping of the heart is a function of involuntary muscles.

(c) Writing with hand is a function of voluntary muscles.

(d) Movement of chocolate in your intestine is a function of involuntary muscles.


43. Fill in the blanks :
(a) Lining of blood vessels is made up of _____
(b) Lining of small intestine is made up of _____
(c) Lining of kidney tubules is made up of _____
(d) Epithelial cells with cilia are found in _____ of our body.

Solution

(a) Lining of blood vessels is made up of squamous epithelium.

(b) Lining of small intestine is made up of columnar epithelium.

(c) Lining of kidney tubules is made up of cuboidal epithelium.

(d) Epithelial cells with cilia are found in respiratory tract of our body.


44. Explain, why water hyacinth float on water surface?

Solution

Water hyacinth float on water surface because of the presence of the air cavities present in the parenchyma tissue.


45. Which structure protects the plant body against the invasion of parasites?

Solution

Epidermis protects the plant body against the invasion of parasites. It has thick cuticle and dermal tissue which help in preventing attack from parasites.


46. Fill in the blanks :
(a) Cork cells possesses _____ on their walls that makes it impervious to gases and water.
(b) _____ have tubular cells with perforated walls and are living in nature.
(c) Bone possesses a hard matrix composed of _____ and _____.

Solution

(a) suberin
(b) Sieve tubes
(c) calcium and phosphate


47. Why is epidermis important for the plants?

Solution

The importance of epidermis is as follows :

  1. Epidermis gives protection against water loss. 
  2. Epidermal cell present on the aerial parts of the plant often secrete a waxy, water resistant layer on their outer surface which provides protection against loss of water, mechanical injury and invasion by parasitic fungi. 
  3. Epidermal tissue forms a continuous layer and helps to avoid mechanical stress.


48. Fill in the blanks :
(a) _____ are forms of complex tissue.
(b) _____ have guard cells.
(c) Cells of cork contain a chemical called _____
(d) Husk of coconut is made of _____ tissue.
(e) _____ gives flexibility in plants.
(f) _____ and _____ are both conducting tissues.
(g) Xylem transports _____ and _____ from soil.
(h) Phloem transport _____ from _____ to other parts of the plant.

Solution

(a) Xylem and phloem
(b) Stomata
(c) suberin
(d) sclerenchyma
(e) Collenchyma
(f) Xylem and phloem
(g) water and minerals
(h) food and leaves


Long Answer Questions

49. Differentiate between sclerenchyma and parenchyma tissues. Draw well labelled diagram.

Solution

Differences between parenchyma and sclerenchyma :

Sclerenchyma tissues

Parenchyma tissues

Consists of living cells

Consists of dead cells

Consists of thin walled cell

Consists of uniformly thickened cell walls

Cellwall is made up of cellulose

Cellwall is made up of complex lignin

Serves as packing tissue

Serves as mechanical tissue

Stores food and perform photosynthesis

Gives strength, rigidity and protects from parasites


50. Describe the structure and functions of different types of epithelial tissues with diagram.

Solution

Epithelial cells are the thin protective coverings that line most of the organs and cavities within the body. It forms a barrier to keep the 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.

Anything entering or leaving the body must cross at least one layer of epithelium. As a result, 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 epithelium is usually separated from the underlying tissue by an extracellular fibrous basement membrane.

Depending on the shape and function, epithelial cells are classified into:

  1. Squamous epithelial tissue
  2. Stratified squamous epithelial tissue
  3. Cuboidal epithelial tissue
  4. Columnar( Ciliated) epithelial tissues)

1. Squamous epithelial tissue: In cell lining, blood vessels or lung alveoli transportation of substances occurs through a selectively permeable surface, this epithelium is a flat kind of epithelium. This is called the simple squamous epithelium. These cells are extremely thin and flat and form a delicate lining. The oesophagus and the lining of the mouth are also covered with squamous epithelium. The skin, which protects the body, is also made of squamous epithelium.

2. Stratified squamous epithelium: Skin epithelial cells are arranged in many layers to prevent wear and tear. Since, they are arranged in a pattern of layers, the epithelium is called stratified squamous epithelium.

3. Columnar epithelium: Tall epithelial cells are present where absorption and secretion occurs, as in the inner lining of the intestine. This columnar epithelial facilitates movement across the epithelial barrier. In the respiratory tract, the columnar epithelial tissue also has cilia, which are hair-like projections on the outer surfaces of epithelial cells.

4. Cuboidal epithelium: These form the lining of the kidney tubules and ducts of salivary glands where these provide mechanical support. Sometimes, a portion of the epithelial tissue folds inward and a multicellular gland is formed. This is glandular epithelium.


51. Draw well labelled diagrams of various types of muscles found in human body.

Solution


52. Give reasons for :
(i) Meristematic cells have a prominent nucleus and dense cytoplasm but they lack vacuole.
(ii) Intercellular spaces are absent in sclerenchymatous tissues.
(iii) We get a crunchy and granular feeling, when we chew pear fruit.
(iv) Branches of a tree move and bend freely in high wind velocity.
(v) It is difficult to pull out the husk of a coconut tree.

Solution

(i) Meristamatic tissue cells divide and they have prominent nucleus and a dese cytoplasm. As they are dividing rigorously they need not store food or waste products. This is the reason they lack vacuoles.

(ii) Cell wall of sclerenchyma are lignified and are packed densely. This in turn protects the plant and gives mechanical strength to the plant. This is the reason why intercellular spaces are absent in sclerenchymatous tissues.

(iii) Sclerenchyma cells are called stone cells in pear fruit. They are small, thick and hard. Because of this we get a crunchy and granular feeling when we chew a pear fruit.

(iv) Junction of a tree branch is composed of collenchyma cells which provide rigidity and flexibility to the branches. This is the reason why branches of a tree move and bend freely in high wind velocity.

(v) Husk of coconut tree is made up of sclerenchyma which is hard. This is the reason why it is difficult to pull out the husk of a coconut tree.


53. List the characteristics of cork. How are they formed? Mention their role.

Solution

Characteristics of cork are as follows:

Cork cells are dead at maturity.

Cork cells are compactly arranged.

Cells do not possess intercellular spaces.

Cells possess a chemical substances suberin in their walls

They have several layers.

With age, the outer protective tissue of the plant undergoes changes. Epidermis of the stem is replaced by a secondary meristem called the phellogen or cork cambium. It is a simple tissue consisting of rectangular cells whose protoplasts are vacuolated. Cork cells contain tanins and chloroplasts.

On the outer side the cork cambium forms cork and on the inner side a secondary cortex by giving off new cells. The layer of cells which is cut by cork cambium on the outer side ultimately becomes several layered thick cork (bark) of trees.

Cork cells are compactly arranged dead cells. Suberin which is fat thickens the walls of cork. Suberin makes the cork cells impermeable to water and gases. Cork provides protection to plant and it prevents the loss of water from plant body. It also protects the plants from infection and mechanical injury. Cork is light in weight and it cannot catch fire. Because of this property it is used as insulators. Cork is hard in nature hence it is used to make sports goods.


54. Why are xylem and phloem called complex tissues ? How are they different from one another ?

Solution

A tissue which has more than one type of cells having a common origin which coordinate to perform a common function is known as specific tissue. As xylem and phloem are made of different types of cells they are called complex tissues.

Difference between Phloem and Xylem

Phloem

Xylem

Transports minerals and water.

Transports food.

Consists of tracheids, vessels, xylem, parenchyma and xylem fibres.

Consist of sieve tubes, companion cell, phloem parenchyma and phloem fibres.

They transport water and minerals vertically from soil to aerial parts of the plant.

They transport food from leaves to other parts of the plant.

Most of the cells except xylem parenchyma are dead cells.

Most of the cells except phloem fibres are living cells.


54. (a) Differentiate between meristematic and permanent tissues in plants.
(b) Define the process of differentiation.
(c) Name any two simple and two complex permanent tissues in plants.

Solution

(a) Difference between meristematic and permanent tissues in plants:

Meristematic tissues

Permanent tissues

Its component cells are living, small, spherical or polygonal and un-differentiated

Its components cells may be living or dead. They are large, differentiated with different shapes.

Cytoplasm is dense and vacuoles are nearly absent as they are metabolically active.

Large central vacuole occurs in living permanent cells as, they are less metabolically active.

Intercellular spaces are absent.

Intercellular spaces are often present.

Cell wall of its cells is thin and elastic.

Cell wall of its cells may either thin or thick.

Nucleus of each cell of this tissue is large and prominent.

Nucleus is less conspicuous.

Its cells grow and divide regularly.

Its cells do not normally divide.

It is a simple tissue.

It can be simple, complex or specialized tissues.

Cell organelles of its cells are simple

Cell organelles of its cells are well developed.

Cell contain crystals and other inclusions.

Cells crystals and other inclusions

It provides growth to the plant.

It provides protection. Support, conduction photosynthesis, storage, etc.

(b) Cells which are derived from the division of meristematic tissues take up specific roles and gradually lose their ability to divide. In this way they form permanent tissues. The process by which the cells divide meristematically to take a permanent shape, size and function is known as differentiation.

(c) The two simple permanent tissues are parenchyma and collenchyma whereas xylem and phloem are two complex permanent tissues.

NCERT Exemplar Chapter 6 Tissues Class 9 Science Solutions

NCERT Exemplar Class 9 Science Chapter 6 Tissues Solutions

NCERT Exemplar Solutions for Class 9 Science Chapter 6 Tissues covers all the important questions and answers as well as advanced level questions. It helps in learning about the functions of tissues, animal tissues like epithelial tissue, connective tissue, muscular and nervous tissue, meristematic plant tissues, role of tissues in plants, permanent tissues like simple tissues and complex tissues.

The NCERT Exemplar solutions for class 9 science is very important in the examination. NCERT Exemplar Solutions for Class 9 Science Chapter 6 Tissues is provided by our experts. They prepared the best solutions which help the students in understanding the solutions in an easy way. This chapters also covers the other topics like meristematic tissue is the only dividing tissue, simple tissues like  parenchyma, collenchyma and sclerenchyma, complex tissues like xylem and phloem, types of epithelial tissue, connective tissues like areolar tissue, adipose tissue, bone, tendon, cartilage and blood and muscular tissues like striated, striated and cardiac.


Chapter Name

Chapter 6 Tissues

Book Title

NCERT Exemplar for Class 9 Science

Related Study

  • NCERT Solutions for Class 9 Science Chapter 6 Tissues
  • Revision Notes for Class 9 Science Chapter 6 Tissues
  • MCQ for Class 9 Science Chapter 6 Tissues
  • Important Questions for Class 9 Science Chapter 6 Tissues

Topics Covered

  • MCQ
  • Short Answers Questions
  • Long Answers Questions

NCERT Exemplar Solutions for Chapter 6 Tissues Class 9 Science

Multiple Choice Questions

1. Which of the following tissues has dead cells?
(a) Parenchyma
(b) Sclerenchyma
(c) Collenchyma
(d) Epithelial tissue

Solution

(b) Sclerenchyma

Sclerenchyma is composed of dead cells which have thick cell wall due to deposition of lignin. They are generally located in the leaf veins, hard coverings of the seeds and can also be found surrounding the vascular bundle.


2. Find out incorrect sentence :
(a) Parenchymatous tissues have intercellular spaces.
(b) Collenchymatous tissues are irregularly thickened at corners.
(c) Apical and intercalary meristems are permanent tissues.
(d) Meristematic tissues, in its early stage, lack vacuoles.

Solution

(c) Apical and intercalary meristems are permanent tissues.

Apical and intercalary meristems are not permanent tissues but they are meristematic tissues which remain in continuous state of division. These tissues differentiate to give rise to the permanent tissues.


3. Girth of stem increases due to :
(a) apical meristem
(b) lateral meristem
(c) intercalary meristem
(d) vertical meristem

Solution

(b) lateral meristem

Lateral meristem occurs on the sides almost parallel to the long axis of the root, stem and its branches. It is responsible for an increase in girth of the stem, i.e. secondary growth.


4. Which cell does not have perforated cell wall?
(a) Tracheids
(b) Companion cells
(c) Sieve tubes
(d) Vessels

Solution

(b) Companion cells


5. Intestine absorb the digested food materials. What type of epithelial cells are responsible for that?
(a) Stratified squamous epithelium
(b) Columnar epithelium
(c) Spindle fibres
(d) Cuboidal epithelium

Solution

(b) Columnar epithelium

Columnar epithelium is pillar-like cell which have nuclei towards its base. They form the lining of stomach, small intestine and colon, forming the mucous membrane. They also the facilitate movement across the epithelial barrier. Their main function is absorption and secretion.


6. A person met with an accident in which two long bones of hand were dislocated. Which among the following may be the possible reason?
(a) Tendon break
(b) Break of skeletal muscle
(c) Ligament break
(d) Areolar tissue break

Solution

(c) Ligament break

When joints held by ligaments get separated dislocation of bones occur. Tendons join the skeletal muscle and they cause inflammation upon break.


7. While doing work and running, you move your organs like hands, legs, etc. Which among the following is correct?
(a) Smooth muscles contract and pull the ligament to move the bones.
(b) Smooth muscles contract and pull the tendons to move the bones.
(c) Skeletal muscles contract and pull the ligament to move the bones.
(d) Skeletal muscles contract and pull the tendon to move the bones.

Solution

(d) Skeletal muscles contract and pull the tendon to move the bones.

Skeletal muscles contract and they pull the tendon, connecting muscles to bones while doing work and running. This moves the bones and they do not pull the ligaments as that will cause a sprain or stretch.


8. Which muscles act involuntarily?
(i) Striated muscles
(ii) Smooth muscles
(iii) Cardiac muscles
(iv) Skeletal muscles
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (i) and (iv)

Solution

(b) (ii) and (iii)

Skeletal muscles are voluntary muscles which are also striated muscles.


9. Meristematic tissues in plants are :
(a) localised and permanent
(b) not limited to certain regions
(c) localised and dividing cells
(d) growing in volume

Solution

(c) localised and dividing cells

Meristematic tissues in plants are the dividing cells. They are responsible for plant growth in certain specific region. Based on the location, meristematic tissues are classified as apical, lateral and intercalary.


10. Which is not a function of epidermis?
(a) Protection from adverse condition
(b) Gaseous exchange
(c) Conduction of water
(d) Transpiration

Solution

(c) Conduction of water

Conduction of water is a function of xylem tissue whereas protection, gaseous exchange and transpiration are the function of epidermis.


11. Select the incorrect sentence :

(a) Blood has matrix containing proteins, salts’ and hormones.
(b) Two bones are connected with ligament.
(c) Tendons are non-fibrous tissue and fragile.
(d) Cartilage is a form of connective tissue.

Solution

(c) Tendons are non-fibrous tissue and fragile.

Tendons are fibrous tissues which are highly elastic and strong.


12. Cartilage is not found in :
(a) nose
(b) ear
(c) kidney
(d) larynx

Solution

(c) kidney

Cartilage is a connective tissue which provides support and flexibility to various parts of our body. Cartilage is found in nose, ear, larynx but not in kidney.


13. Fats are stored in human body as :
(a) cuboidal epithelium
(b) adipose tissue
(c) bones
(d) cartilage

Solution

(b) adipose tissue

Fat is stored in the adipose tissue present below the skin and between internal organs. Cells in these tissues are filled with fat globules.


14. Bone matrix is rich in :
(a) fluoride and calcium
(b) calcium and phosphorus
(c) calcium and potassium
(d) phosphorus and potassium

Solution

(b) calcium and phosphorus


15. Contractile proteins are found in :
(a) bones
(b) blood
(c) muscles
(d) cartilage

Solution

(c) muscles

Contractile proteins are responsible for the contraction and relaxation of muscles.


16. Voluntary muscles are found in :
(a) alimentary canal
(b) limbs
(c) iris of the eye
(d) bronchi of lungs

Solution

(b) limbs

Some muscles can be moved by our own will. Muscles present in our limbs can move at our will, and stop when we decide to. Such muscles are called voluntary muscles.


17. Nervous tissue is not found in :
(a) brain
(b) spinal cord
(c) tendons
(d) nerves

Solution

(c) tendons

Tendons are the connective tissue which connects muscles to bones. They are fibrous in nature and gives strength and limited flexibility.


18. Nerve cell does not contain :
(a) axon
(b) nerve endings
(c) tendons
(d) dendrites

Solution

(c) tendons

Neurons are connective tissues that join skeletal muscles to bones, so they do not contain tendons.


19. Which of the following helps in repair of tissue and fills up the space inside the organ?
(a) Tendon
(b) Adipose tissue
(c) Areolar
(d) Cartilage

Solution

(c) Areolar

Areolar connective tissue is found between the skin and muscles, around blood vessels and nerves and in the bone marrow. It fills the space inside the organs, supports internal organs and helps in repair of tissues.


20. The muscular tissue which function throughout the life continuously without fatigue is :
(a) skeletal muscle
(b) cardiac muscle
(c) smooth muscle
(d) voluntary muscle

Solution

(b) cardiac muscle

Heart muscles are cylindrical, branched and uninucleated. They show rhythmic contraction and relaxation throughout life. Skeletal muscle, smooth muscle and voluntary muscles work as and when required.


21. Which of the following cells is found in the cartilaginous
tissue of the body?
(a) Mast cells
(b) Basophils
(c) Osteocytes
(d) Chondrocytes

Solution

(d) Chondrocytes

Mast cells are found in areolar tissue. Basophils are found in blood. Osteocytes are found in bone.


22. The dead element present in the phloem is :
(a) companion cells
(b) phloem fibres
(c) phloem parenchyma
(d) sieve tubes

Solution

(b) phloem fibres

Phloem fibres possess narrow lumen and thick-walls. They are elongated spindle-shaped dead cell. It provides mechanical support to the tissue. Phloem parenchyma is the thin-walled living cells of parenchyma.


23. Which of the following does not lose their nucleus at maturity?
(a) Companion cells
(b) Red blood cells
(c) Vessel
(d) Sieve tube cells

Solution

(a) Companion cells


24. In desert plants, rate of water loss gets reduced due to the presence of :
(a) cuticle
(b) stomata
(c) lignin
(d) suberin

Solution

(a) cuticle

Cuticle is a protective layer covering epidermis of the leaf, young shoots and other aerial parts of a plant. Cuticle minimizes the effect of heat and reduces the loss of water as it contains lipids and polymers impregnated with wax.


25. A long tree has several branches. The tissue that helps in the sideways conduction of water in the branches is :
(a) collenchyma
(b) xylem parenchyma
(c) parenchyma
(d) xylem vessels

Solution

(d) xylem vessels

Collenchyma is an active tissue and has no role in the conduction of water. Parenchyma is a supportive tissue. Xylem vessels also known as xylem trachea are responsible for conduction of water in plants.


26. If the tip of sugarcane plant is removed from the field, even then it keeps on growing in length. It is due to the presence of :
(a) cambium
(b) apical meristem
(c) lateral meristem
(d) intercalary meristem

Solution

(d) intercalary meristem

Intercalary meristem is responsible for the longitudinal growth of the plant even in the absence of apical meristem.


27. A nail is inserted in the trunk of a tree at a height of 1 metre from the ground level. After 3 years the nail will :
(a) move downwards
(b) move upwards
(c) remain at the same position
(d) move sideways

Solution

(c) remain at the same position

Longitudinal growth in the stem always takes place on the top. The apical meristem in the lower region remains constant. This is the reason why there will be no change in position of nail inserted in the trunk of the tree.


28. Parenchyma cells are :
(a) relatively unspecified and thin walled
(b) thick walled and specialised
(c) lignified
(d) None of these

Solution

(a) relatively unspecified and thin walled

The most common simple permanent tissue is the parenchyma. It consists of relatively unspecialized cells with thin cell walls. They are living cells. They are usually loosely arranged, thus large spaces between cells (intercellular spaces) are found in this tissue.


29. Flexibility in plants is due to :
(a) collenchyma
(b) sclerenchyma
(c) parenchyma
(d) chlorenchyma

Solution

(a) collenchyma


30. Cork cells are made impervious to water and gases by the presence of :
(a) cellulose
(b) lipids
(c) suberin
(d) lignin

Solution

(c) suberin


31. Survival of plants in terrestrial environment has been made possible by the presence of :
(a) intercalary meristem
(b) conducting tissue
(c) apical meristem
(d) parenchymatous tissue

Solution

(b) conducting tissue

Xylem and phloem which are the conducting tissues are responsible for the survival of plants in terrestrial environment. Xylem conduct water from roots to all the parts of the plants and phloem transports food and other nutrients from leaves to other parts of the plant.


32. Choose the wrong statement.
(a) The nature of matrix differs according to the function of the tissue.
(b) Fats are stored below the skin and in between the internal organ
(c) Epithelial tissues have intercellular spaces between them.
(d) Cells of striated muscles are multinucleate and unbranched.

Solution

(c) Epithelial tissues have intercellular spaces between them.

Epithelial tissues do not have intercellular spaces between them. They are tightly bound together to make continuous sheet.


33. The water conducting tissue generally present in gymnosperm is :
(a) vessel
(b) sieve tube
(c) tracheids
(d) xylem fibres

Solution

(c) tracheids

Vessels are generally absent in gymnosperms. Sieve tubes are present in phloem. Xylem fibres provide structural rigidity and have no role in conduction of water.


Short Answer Questions

34. Why animals of colder regions and fishes of cold water have thicker layer of subcutaneous fat?

Solution

Animals of colder regions and fishes of cold water have thicker layer of subcutaneous fat. This acts as an insulator and prevents the escape of heat from their body.


35. Match the column (A) with the column (B).

 

Column (A)

 

Column (B)

(1)

Parenchyma

(1)

Thin walled, packing cells

(2)

Photosynthesis

(2)

Carbon fixation

(3)

Aerenchyma

(3)

Localized thickenings

(4)

Collenchyma

(4)

Buoyancy

(5)

Permanent tissue

(5)

Sclerenchyma

Solution

(A)

(B)

(a) Parenchyma

(i) Thin-walled, packing cells

(b) Photosynthesis

(ii) Carbon fixation

(c) Aerenchyma

(iv) Buoyancy

(d) Collenchyma

(iii) Localized thickenings

(e) Permanent tissue

(v) Sclerenchyma


36. Match the column (A) with the column (B).

(A)

(B)

(a) Fluid connective tissue

(i) Subcutaneous layer

(b) Filling of space inside the organs

(ii) Cartilage

(c) Striated muscle

(iii) Skeletal muscle

(d) Adipose tissue

(iv) Areolar tissue

(e) Surface of joints

(v) Blood

(f) Stratified squamous epithelium

(vi) Ski

Solution

(A)

(B)

(a) Fluid connective tissue

(v) Blood

(b) Filling of space inside the organs

(iv) Areolar tissue

(c) Striated muscle

(iii) Skeletal muscle

(d) Adipose tissue

(i) Subcutaneous layer

(e) Surface of joints

(ii) Cartilage

(f) Stratified squamous epithelium

(vi) Ski


37. If a potted plant is covered with a glass jar, water vapours appear on the wall of glass jar. Explain, why?

Solution

Water is released from the plants in the form of vapours because of the process called transpiration.


38. Name the different components of xylem and draw a living component.

Solution

The different components of xylem are:

  1. tracheids
  2. vessels
  3. xylem parenchyma
  4. xylem fibres.

The only living component of xylem is xylem parenchyma.


39. Draw and identify different elements of phloem.

Solution


40. Differentiate between voluntary and involuntary muscles. Give one example of each type.

Solution

Voluntary muscles

Involuntary muscles

They are also called striated muscles since they show stripes or striations.

They are also called non-striated muscles since they lack striations.

Their cells are long and cylindrical.

Their cells are small and spindle shaped.

They have multinucleate cells.

They have uninucleate cells.

They are under our will or control.

They are not under our will or control.

They get tired and need rest at intervals.

They can work continuously without getting tired.

Example: Limb muscles

Example: Cardiac muscles


41. Write true (T) or false (F) :
(a) Epithelial tissue is protective tissue in animal body.
(b) The lining of blood vessels, lung alveoli and kidney tubules are all made up of epithelial tissue.
(c) Epithelial cells have a lot of intercellular spaces.
(d) Epithelial layer is permeable layer.
(e) Epithelial layer does not allow regulation of materials between body and external environment.

(a) True,

(b) True

(c) False

(d) True

(e) False


42. Differentiate the following activities on the basis of voluntary or involuntary muscles :
(a) Jumping of frog
(b) Pumping of the heart
(c) Writing with hand
(d) Movement of chocolate in your intestine

Solution

(a) Jumping of frog is an activity of voluntary muscles.

(b) Pumping of the heart is a function of involuntary muscles.

(c) Writing with hand is a function of voluntary muscles.

(d) Movement of chocolate in your intestine is a function of involuntary muscles.


43. Fill in the blanks :
(a) Lining of blood vessels is made up of _____
(b) Lining of small intestine is made up of _____
(c) Lining of kidney tubules is made up of _____
(d) Epithelial cells with cilia are found in _____ of our body.

Solution

(a) Lining of blood vessels is made up of squamous epithelium.

(b) Lining of small intestine is made up of columnar epithelium.

(c) Lining of kidney tubules is made up of cuboidal epithelium.

(d) Epithelial cells with cilia are found in respiratory tract of our body.


44. Explain, why water hyacinth float on water surface?

Solution

Water hyacinth float on water surface because of the presence of the air cavities present in the parenchyma tissue.


45. Which structure protects the plant body against the invasion of parasites?

Solution

Epidermis protects the plant body against the invasion of parasites. It has thick cuticle and dermal tissue which help in preventing attack from parasites.


46. Fill in the blanks :
(a) Cork cells possesses _____ on their walls that makes it impervious to gases and water.
(b) _____ have tubular cells with perforated walls and are living in nature.
(c) Bone possesses a hard matrix composed of _____ and _____.

Solution

(a) suberin
(b) Sieve tubes
(c) calcium and phosphate


47. Why is epidermis important for the plants?

Solution

The importance of epidermis is as follows :

  1. Epidermis gives protection against water loss. 
  2. Epidermal cell present on the aerial parts of the plant often secrete a waxy, water resistant layer on their outer surface which provides protection against loss of water, mechanical injury and invasion by parasitic fungi. 
  3. Epidermal tissue forms a continuous layer and helps to avoid mechanical stress.


48. Fill in the blanks :
(a) _____ are forms of complex tissue.
(b) _____ have guard cells.
(c) Cells of cork contain a chemical called _____
(d) Husk of coconut is made of _____ tissue.
(e) _____ gives flexibility in plants.
(f) _____ and _____ are both conducting tissues.
(g) Xylem transports _____ and _____ from soil.
(h) Phloem transport _____ from _____ to other parts of the plant.

Solution

(a) Xylem and phloem
(b) Stomata
(c) suberin
(d) sclerenchyma
(e) Collenchyma
(f) Xylem and phloem
(g) water and minerals
(h) food and leaves


Long Answer Questions

49. Differentiate between sclerenchyma and parenchyma tissues. Draw well labelled diagram.

Solution

Differences between parenchyma and sclerenchyma :

Sclerenchyma tissues

Parenchyma tissues

Consists of living cells

Consists of dead cells

Consists of thin walled cell

Consists of uniformly thickened cell walls

Cellwall is made up of cellulose

Cellwall is made up of complex lignin

Serves as packing tissue

Serves as mechanical tissue

Stores food and perform photosynthesis

Gives strength, rigidity and protects from parasites


50. Describe the structure and functions of different types of epithelial tissues with diagram.

Solution

Epithelial cells are the thin protective coverings that line most of the organs and cavities within the body. It forms a barrier to keep the 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.

Anything entering or leaving the body must cross at least one layer of epithelium. As a result, 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 epithelium is usually separated from the underlying tissue by an extracellular fibrous basement membrane.

Depending on the shape and function, epithelial cells are classified into:

  1. Squamous epithelial tissue
  2. Stratified squamous epithelial tissue
  3. Cuboidal epithelial tissue
  4. Columnar( Ciliated) epithelial tissues)

1. Squamous epithelial tissue: In cell lining, blood vessels or lung alveoli transportation of substances occurs through a selectively permeable surface, this epithelium is a flat kind of epithelium. This is called the simple squamous epithelium. These cells are extremely thin and flat and form a delicate lining. The oesophagus and the lining of the mouth are also covered with squamous epithelium. The skin, which protects the body, is also made of squamous epithelium.

2. Stratified squamous epithelium: Skin epithelial cells are arranged in many layers to prevent wear and tear. Since, they are arranged in a pattern of layers, the epithelium is called stratified squamous epithelium.

3. Columnar epithelium: Tall epithelial cells are present where absorption and secretion occurs, as in the inner lining of the intestine. This columnar epithelial facilitates movement across the epithelial barrier. In the respiratory tract, the columnar epithelial tissue also has cilia, which are hair-like projections on the outer surfaces of epithelial cells.

4. Cuboidal epithelium: These form the lining of the kidney tubules and ducts of salivary glands where these provide mechanical support. Sometimes, a portion of the epithelial tissue folds inward and a multicellular gland is formed. This is glandular epithelium.


51. Draw well labelled diagrams of various types of muscles found in human body.

Solution


52. Give reasons for :
(i) Meristematic cells have a prominent nucleus and dense cytoplasm but they lack vacuole.
(ii) Intercellular spaces are absent in sclerenchymatous tissues.
(iii) We get a crunchy and granular feeling, when we chew pear fruit.
(iv) Branches of a tree move and bend freely in high wind velocity.
(v) It is difficult to pull out the husk of a coconut tree.

Solution

(i) Meristamatic tissue cells divide and they have prominent nucleus and a dese cytoplasm. As they are dividing rigorously they need not store food or waste products. This is the reason they lack vacuoles.

(ii) Cell wall of sclerenchyma are lignified and are packed densely. This in turn protects the plant and gives mechanical strength to the plant. This is the reason why intercellular spaces are absent in sclerenchymatous tissues.

(iii) Sclerenchyma cells are called stone cells in pear fruit. They are small, thick and hard. Because of this we get a crunchy and granular feeling when we chew a pear fruit.

(iv) Junction of a tree branch is composed of collenchyma cells which provide rigidity and flexibility to the branches. This is the reason why branches of a tree move and bend freely in high wind velocity.

(v) Husk of coconut tree is made up of sclerenchyma which is hard. This is the reason why it is difficult to pull out the husk of a coconut tree.


53. List the characteristics of cork. How are they formed? Mention their role.

Solution

Characteristics of cork are as follows:

Cork cells are dead at maturity.

Cork cells are compactly arranged.

Cells do not possess intercellular spaces.

Cells possess a chemical substances suberin in their walls

They have several layers.

With age, the outer protective tissue of the plant undergoes changes. Epidermis of the stem is replaced by a secondary meristem called the phellogen or cork cambium. It is a simple tissue consisting of rectangular cells whose protoplasts are vacuolated. Cork cells contain tanins and chloroplasts.

On the outer side the cork cambium forms cork and on the inner side a secondary cortex by giving off new cells. The layer of cells which is cut by cork cambium on the outer side ultimately becomes several layered thick cork (bark) of trees.

Cork cells are compactly arranged dead cells. Suberin which is fat thickens the walls of cork. Suberin makes the cork cells impermeable to water and gases. Cork provides protection to plant and it prevents the loss of water from plant body. It also protects the plants from infection and mechanical injury. Cork is light in weight and it cannot catch fire. Because of this property it is used as insulators. Cork is hard in nature hence it is used to make sports goods.


54. Why are xylem and phloem called complex tissues ? How are they different from one another ?

Solution

A tissue which has more than one type of cells having a common origin which coordinate to perform a common function is known as specific tissue. As xylem and phloem are made of different types of cells they are called complex tissues.

Difference between Phloem and Xylem

Phloem

Xylem

Transports minerals and water.

Transports food.

Consists of tracheids, vessels, xylem, parenchyma and xylem fibres.

Consist of sieve tubes, companion cell, phloem parenchyma and phloem fibres.

They transport water and minerals vertically from soil to aerial parts of the plant.

They transport food from leaves to other parts of the plant.

Most of the cells except xylem parenchyma are dead cells.

Most of the cells except phloem fibres are living cells.


54. (a) Differentiate between meristematic and permanent tissues in plants.
(b) Define the process of differentiation.
(c) Name any two simple and two complex permanent tissues in plants.

Solution

(a) Difference between meristematic and permanent tissues in plants:

Meristematic tissues

Permanent tissues

Its component cells are living, small, spherical or polygonal and un-differentiated

Its components cells may be living or dead. They are large, differentiated with different shapes.

Cytoplasm is dense and vacuoles are nearly absent as they are metabolically active.

Large central vacuole occurs in living permanent cells as, they are less metabolically active.

Intercellular spaces are absent.

Intercellular spaces are often present.

Cell wall of its cells is thin and elastic.

Cell wall of its cells may either thin or thick.

Nucleus of each cell of this tissue is large and prominent.

Nucleus is less conspicuous.

Its cells grow and divide regularly.

Its cells do not normally divide.

It is a simple tissue.

It can be simple, complex or specialized tissues.

Cell organelles of its cells are simple

Cell organelles of its cells are well developed.

Cell contain crystals and other inclusions.

Cells crystals and other inclusions

It provides growth to the plant.

It provides protection. Support, conduction photosynthesis, storage, etc.

(b) Cells which are derived from the division of meristematic tissues take up specific roles and gradually lose their ability to divide. In this way they form permanent tissues. The process by which the cells divide meristematically to take a permanent shape, size and function is known as differentiation.

(c) The two simple permanent tissues are parenchyma and collenchyma whereas xylem and phloem are two complex permanent tissues.

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