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Page No 40:
Question 1:
Which of the following tissues has dead cells?
(a) Parenchyma
(b) Sclerenchyma
(c) Collenchyma
(d) Epithelial tissue
Answer:
Simple permanent tissue is of 3 types - parenchyma, collenchyma & sclerenchyma, but out of these three only sclerenchyma is dead tissue which comprises of fibres & sclereids, due to the deposition of lignin.
Hence, the correct option is (b).
Page No 40:
Question 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 their early stage, lack vacuoles
Answer:
Meristems comprise actively dividing cells like apical, intercalary & lateral meristem. They are not specialized to perform any function. Meristematic tissues become permanent when they lost their ability to divide and take up a specific function.
Hence, the correct option is (c).
Page No 40:
Question 3:
Girth of stem increases due to
(a) apical meristem
(b) lateral meristem
(c) intercalary meristem
(d) vertical meristem
Answer:
Meristematic cells are actively dividing cells. Apical & intercalary are responsible for increasing the length or height of the plant whereas the girth of stem increases due to the activity of lateral meristem.
Hence, the correct option is (b).
Page No 40:
Question 4:
Which cell does not have perforated cell wall?
(a) Tracheids
(b) Companion cells
(c) Sieve tubes
(d) Vessels
Answer:
Tracheids, sieve tubes and vessels have perforated walls for the transfer of food through them but the companion cells do not have perforated cell wall instead they help in regulating the activity of sieve tubes which do not have a nucleus.
Hence, the correct option is (b).
Page No 40:
Question 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
Answer:
The columnar epithelium is the cells which posses a nucleus at the bottom and due to large surface area are actively involved in absorption purposes. So, in the intestine, they help in the absorption of digested food materials.
Hence, the correct option is (b).
Page No 40:
Question 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
Answer:
A person met with an accident in which two long bones of hand were dislocated, the possible reason for this is ligament break as bones are joined together with the help of ligament.
Hence, the correct option is (c).
Page No 41:
Question 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
Answer:
Tendon is a connective tissue that attaches muscles to the bones. While doing work and running, you move your organs like hands, legs etc. Our skeletal muscles contract and pull the tendon to move the bones.
Hence, the correct option is (d).
Page No 41:
Question 8:
Which muscles act involuntarily?
(i) Striated muscles
(ii) Smooth muscles
(iii) Cardiac muscles
(iv) Skeletal muslces
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (i) and (iv)
Answer:
We can not move involuntary muscles according to our will. The involuntary muscles in our body are smooth muscles & cardiac muscles.
Hence, the correct option is (b).
Page No 41:
Question 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
Answer:
Meristematic tissues in plants are localised, that is, they are found in certain regions of the plant. They are young and dividing cells.
Hence, the correct option is (c).
Page No 41:
Question 10:
Which is not a function of epidermis?
(a) Protection from adverse condition
(b) Gaseous exchange
(c) Conduction of water
(d) Transpiration
Answer:
Conduction of water is done by the xylem, not by the epidermis. The epidermis helps in all other functions like protection, gaseous exchange and transpiration.
Hence, the correct option is (c).
Page No 41:
Question 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
Answer:
Tendons are strong fibrous tissue and tensile in nature. It connects muscles with bones.
Hence, the correct option is (c).
Page No 41:
Question 12:
Cartilage is not found in
(a) nose
(b) ear
(c) kidney
(d) larynx
Answer:
Cartilage is a type of connective tissue that provides flexibility. It is present in the nose, ear, larynx, trachea, vertebral column but not present in the kidney.
Hence, the correct option is (c).
Page No 42:
Question 13:
Fats are stored in human body as
(a) cuboidal epithelium
(b) adipose tissue
(c) bones
(d) cartilage
Answer:
Fats are stored in human body as adipose tissue. The cells of the adipose tissue are called adipocytes.
Hence, the correct option is (b).
Page No 42:
Question 14:
Bone matrix is rich in
(a) fluoride and calcium
(b) calcium and phosphorus
(c) calcium and potassium
(d) phosphorus and potassium
Answer:
Bone matrix is rich in calcium and phosphorus.
Hence, the correct option is (b).
Page No 42:
Question 15:
Contractile proteins are found in
(a) bones
(b) blood
(c) muscles
(d) cartilage
Answer:
Contractile proteins are found in muscles. They help in muscle contraction and relaxation.
Hence, the correct option is (c).
Page No 42:
Question 16:
Voluntary muscles are found in
(a) alimentary canal
(b) limbs
(c) iris of the eye
(d) bronchi of lungs
Answer:
Voluntary muscles are the skeletal muscles or can also be called striated muscles due to appearance of alternate light and dark bands in them. They are found in limbs, help in movement and are under our control.
Hence, the correct option is (b).
Page No 42:
Question 17:
Nervous tissue is not found in
(a) brain
(b) spinal cord
(c) tendons
(d) nerves
Answer:
Nervous tissue is made up of neurons which help us in responding to the changes in surroundings (stimulus). They are found in the brain, spinal cord & nerves arising from them. Tendons, on the other hand, are part of the connective tissue that connects muscles with bones.
Hence, the correct option is (c).
Page No 42:
Question 18:
Nerve cell does not contain
(a) axon
(b) nerve endings
(c) tendons
(d) dendrites
Answer:
Nerve cell or neuron has parts like cell body or cyton which posses the nucleus, there are few projections coming out of the cyton which are called dendrites which receives the information and transfer it to the axon (the longest projection) which further transfers impulse to nerve endings. So, axon, nerve endings & dendrites are the parts of neuron.
Hence, the correct option is (c).
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Question 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
Answer:
The connective tissues are of various types but one with a soft matrix called proper connective tissue includes areolar connective tissue which helps in tissue repair and filling the space inside the organ.
Hence, the correct option is (c).
Page No 43:
Question 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
Answer:
The muscles are of 3 types - skeletal, smooth and cardiac. Both Smooth and cardiac muscles are involuntary but only the cardiac muscles function continuously throughout their life without fatigue and help in the continuous pumping of blood through the heart. Whereas the other two muscles undergo fatigue.
Hence, the correct option is (b).
Page No 43:
Question 21:
Which of the following cells is found in the cartilaginous tissue of the body?
(a) Mast cells
(b) Basophils
(c) Osteocytes
(d) Chondrocytes
Answer:
Chondrocytes are the cells found in the cartilaginous tissue of the body. In cartilage tissue, these cells are embedded in a protein-containing matrix, which is strong yet flexible in nature.
Hence, the correct option is (d).
Page No 43:
Question 22:
The dead element present in the phloem is
(a) companion cells
(b) phloem fibres
(c) phloem parenchyma
(d) sieve tubes
Answer:
Phloem fibres are the dead elements of the phloem. These cells provide mechanical strength to the tissue. Other than these cells, all elements of phloem are living and help in the storage and conduction of food.
Hence, the correct option is (b).
Page No 43:
Question 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
Answer:
Companion cells do not lose their nucleus at maturity as they are metabolically active cells and other cells like sieve tube elements are dependent on these cells for their function.
Hence, the correct option is (a).
Page No 43:
Question 24:
In desert plants, rate of water loss gets reduced due to the presence of
(a) cuticle
(b) stomata
(c) lignin
(d) suberin
Answer:
The cuticle is found on the epidermis of the leaf that minimizes the effect of heat and reduces the loss of water in desert plants. It acts as a protective layer which is also found in the young shoots and other aerial parts of the plant.
Hence, the correct option is (a).
Page No 43:
Question 25:
A long tree has several branches. The tissue that helps in the side ways conduction of water in the branches is
(a) collenchyma
(b) xylem parenchyma
(c) parenchyma
(d) xylem vessels
Answer:
The xylem parenchyma helps in storing food and the sideways conduction of water. Other components of xylem such as xylem fibres provide support, while tracheids and vessels help in the vertical transportation of water and nutrients.
Hence, the correct option is (b).
Page No 43:
Question 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
Answer:
Due to the presence of intercalary meristem, the sugarcane plant will keep on growing in length. The intercalary meristem is found at the base of the leaves or internodes. It helps in the longitudinal growth of plants.
Hence, the correct option is (d).
Page No 44:
Question 27:
A nail is inserted in the trunk of a tree at a height of 1 meter 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
Answer:
The position of the nail in the given case will not change and it will still remain at a height of 1 meter from the ground. This is because the growth in trees occurs in the apical regions due to apical meristem. There is no apical meristem at the point where nail was inserted.
Hence, the correct option is (c).
Page No 44:
Question 28:
Parenchyma cells are
(a) relatively unspecified and thin walled
(b) thick walled and specialised
(c) lignified
(d) none of these
Answer:
Parenchyma cells consist of relatively unspecialised 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.
Hence, the correct option is (a).
Page No 44:
Question 29:
Flexibility in plants is due to
(a) collenchyma
(b) sclerenchyma
(c) parenchyma
(d) chlorenchyma
Answer:
Collenchyma tissues are composed of elongated cells with irregular thickening in cell walls along the corners. The collenchyma provides flexibility to plants and allows the bending of various parts of plants such as leaves and stems.
Hence, the correct option is (a).
Page No 44:
Question 30:
Cork cells are made impervious to water and gases by the presence of
(a) cellulose
(b) lipids
(c) suberin
(d) lignin
Answer:
Cells of cork are dead and compactly arranged without intercellular spaces. Suberin present in cork cells makes them impermeable to gases and water. It forms a hydrophobic barrier around the plant.
Hence, the correct option is (c).
Page No 44:
Question 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
Answer:
The conducting or vascular tissue of plants are xylem and phloem. Xylem conducts water and minerals in the plants while phloem conducts food which makes the survival of plants in the terrestrial environment possible.
Hence, the correct option is (b).
Page No 44:
Question 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 organs
(c) Epithelial tissues have intercellular spaces between them
(d) Cells of striated muscles are multinucleate and unbranched
Answer:
The covering or protective tissues in the animal body are epithelial tissues. The cells of this tissue are tightly packed and form a continuous sheet. They have only a small amount of cementing material between them and almost no intercellular spaces.
Hence, the correct option is (c).
Page No 45:
Question 33:
The water conducting tissue generally present in gymnosperm is
(a) vessels
(b) sieve tube
(c) tracheids
(d) xylem fibres
Answer:
Tracheids and vessels are tubular structures that allow the transportation of water and minerals vertically in a plant. Vessels are generally absent in gymnosperms so tracheids conduct water and minerals in them.
Hence, the correct option is (c).
Page No 45:
Question 34:
Animals of colder regions and fishes of cold water have thicker layer of subcutaneous fat. Describe why?
Answer:
The presence of a thick layer of subcutaneous fat acts as an insulator in animals of the colder regions. This layer prevents heat loss and keeps the animal warm in a colder climate.
Page No 45:
Question 35:
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) | Skin |
Answer:
| (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) | Skin |
Page No 45:
Question 36:
Match the column (A) with the column (B)
| (A) | (B) | ||
| (a) | Parenchyma | (i) | Thin walled, packing cells |
| (b) | Photosynthesis | (ii) | Carbon fixation |
| (c) | Aerenchyma | (iii) | Localized thickenings |
| (d) | Collenchyma | (iv) | Buoyancy |
| (e) | Permanent tissue | (v) | Sclerenchyma |
Answer:
| (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 |
Page No 45:
Question 37:
If a potted plant is covered with a glass jar, water vapours appear on the wall of glass jar. Explain why?
Answer:
A plant undergoes the process of transpiration which is a loss of water through the stomata in the form of water vapour. That is why when the potted plant is kept in a glass jar, the vapours released due to the process of transpiration cool down and appear on the wall of the glass jar.
Page No 45:
Question 38:
Name the different components of xylem and draw a living component?
Answer:
Xylem consists of tracheids, vessels, xylem parenchyma and xylem fibres. The only component of the xylem that is living is the xylem parenchyma cell. 
Xylem parenchyma
Page No 45:
Question 39:
Draw and identify different elements of phloem.
Answer:
The different elements of phloem are- sieve tubes, companion cells, phloem fibres and the phloem parenchyma.
Phloem tissue
Page No 46:
Question 40:
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.
Answer:
(a) True.
(b) True.
(c) False, Epithelial cells have almost no intercellular spaces.
(d) True.
(e) False, Squamous epithelial cells play an important role in regulating the exchange of materials between the body and the external environment.
Page No 46:
Question 41:
Differentiate between voluntary and involuntary muscles. Give one example of each type.
Answer:
| Voluntary muscles | Involuntary muscles |
| 1. They show striations due to the presence of alternative light and dark bands. | 1. Some show striations (cardiac muscles) while others do not (smooth muscles). |
| 2. Movement of these muscles is under the will of the organism. | 2. Movement of these muscles is not under the will of the organism. |
| 3. These muscles consist of multinucleate cells. | 3. These muscles consist of uninucleate cells. |
| 4. The cells are cylindrical in structure. | 4. The cells are spindle-shaped or branched. |
| 5. These muscles are found in the hands, legs, tongue etc. | 5. These muscles are found in the iris of the eye, in ureters, in the bronchi of the lungs and in the heart. |
Page No 46:
Question 42:
Differentiate the following activities on the basis of voluntary (V) or involuntary (IV) muscles.
(a) Jumping of frog
(b) Pumping of the heart
(c) Writing with hand
(d) Movement of chocolate in your intestine
Answer:
| Voluntary (V) | Involuntary (IV) |
| (a) Jumping of frog | (b) Pumping of the heart |
| (c) Writing with hand | (d) Movement of chocolate in your intestine |
Page No 46:
Question 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.
Answer:
(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 the respiratory tract of our body.
Page No 46:
Question 44:
Water hyacinth float on water surface. Explain.
Answer:
Water hyacinth is an aquatic plant and in such types of plants, large air cavities are present in parenchyma to help them float. Such a type of parenchyma is called aerenchyma.
Page No 46:
Question 45:
Which structure protects the plant body against the invasion of parasites?
Answer:
The entire surface of a plant has an outer covering called the epidermis. It protects all the parts of the plant including stem, leaves, roots, fruits etc. Epidermal cells on the aerial parts of the plant often secrete a waxy, water-resistant layer on their outer surface called the cuticle. This aids in protection against loss of water, mechanical injury and invasion by parasites.
Page No 46:
Question 46:
Fill in the blanks
(a) Cork cells possess ___________ on their walls that makes them 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 ___________.
Answer:
(a) Cork cells possess suberin on their walls that makes them impervious to gases and water.
(b) Sieve tubes have tubular cells with perforated walls and are living in nature.
(c) Bone possesses a hard matrix composed of calcium and phosphorus.
Page No 46:
Question 47:
Why is epidermis important for the plants?
Answer:
The outermost layer of cells in a plant is called the epidermis. The epidermis covers the stem, root, leaf, flower, fruit, and seed parts of a plant. The epidermis is usually made of a single layer of cells. In some plants living in very dry habitats, the epidermis secretes a thick, waxy substance called cuticle which protects the plant against water loss. It also aids in protection against mechanical injury and invasion by parasitic fungi.
Page No 47:
Question 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 to plants.
(f) __________ and __________ are both conducting tissues.
(g) Xylem transports __________ and __________ from soil.
(h) Phloem transports __________ from __________ to other parts of the plant.
Answer:
(a) Xylem and phloem are forms of complex tissue.
(b) Stomata have guard cells.
(c) Cells of cork contain a chemical called suberin.
(d) Husk of coconut is made of sclerenchyma.
(e) Collenchyma gives flexibility to 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.
Page No 47:
Question 49:
Differentiate between sclerenchyma and parenchyma tissues. Draw well labelled diagram.
Answer:
| Sclerenchyma | Parenchyma |
| 1. It consists of long and narrow dead cells. | 1. It consists of loosely packed living cells. |
| 2. The cell wall of these cells is thick-walled due to the deposition of lignin. | 2. It is composed of unspecialized cells with relatively thin cell walls. |
| 3. The cells of this tissue do not have intercellular spaces between them. | 3. The cells of this tissue have intercellular spaces between them. |
| 4. ​They provide mechanical strength to the plant. | 4. They perform the function of storage. |
Parenchyma-
Sclerenchyma-
Page No 47:
Question 50:
Describe the structure and function of different types of epithelial tissues. Draw diagram of each type of epithelial tissue.
Answer:
Types of epithelial tissue-
1. Squamous epithelium- It is a single layer of thin and flat cells. The cells are very thin with a delicate lining. Some examples of simple squamous epithelium are the lining of the mouth, esophagus, lung alveoli and small blood vessels.
Epithelial cells in the skin are arranged in many layers to prevent wear and tear. This type of multilayered epithelium is known as the stratified squamous epithelium.
2. Cuboidal epithelium- It consists of cube-like cells. These tissues are present in the lining of kidney tubules and ducts of salivary glands. Some special cuboidal cells form the surface of secretory glands and gland cells.
3. Columnar epithelium- It consists of elongated or column-like cells. These tissues are mainly found in the parts where absorption and secretion occur. Some examples of columnar epithelium are the inner linings of the intestine and stomach.
4. Ciliated epithelium- It consists of columnar/cuboidal cells that bear cilia on their surface. The cilia help in the movement of particles in a specific direction over the epithelium. This type of epithelium is present in the respiratory tract.
5. Glandular epithelium- It consists of columnar/cuboidal cells that have become specialized for secretion. When a portion of the epithelial tissue folds inward, glandular epithelium is formed. The function of glandular epithelium is to secrete chemicals, for example, the endocrine glands, which secrete hormones.
Page No 47:
Question 51:
Draw well labelled diagrams of various types of muscles found in human body.
Answer:
Types of muscles found in the human body are-
(i) Skeletal muscles
Skeletal muscles
(ii) Smooth muscles
(iii) Cardiac muscles
Page No 47:
Question 52:
Give reasons for
(a) Meristematic cells have a prominent nucleus and dense cytoplasm but they lack vacuole.
(b) Intercellular spaces are absent in sclerenchymatous tissues.
(c) We get a crunchy and granular feeling, when we chew pear fruit.
(d) Branches of a tree move and bend freely in high wind velocity.
(e) It is difficult to pull out the husk of a coconut tree.
Answer:
(a) Meristematic tissue cells are continuously dividing and are very active. They have a prominent nucleus, a thin cellulose wall, and a dense cytoplasm. They lack vacuoles as there is no need to store food or waste products.
(b) The cell wall of sclerenchyma tissue is composed of lignin. They are densely packed to protect the plant and provide mechanical strength. Due to this, the intercellular spaces are absent in the sclerenchyma tissue.
(c) The pear fruit contains sclerenchyma tissue that has small, rounded cells called stone cells. These cells are hard with highly thickened cell walls that give a crunchy and granular feeling when one chews pear fruit.
(d) Branches of a tree move and bend freely in high wind velocity because the Junction of the branch of a tree is composed of collenchyma tissue that provides rigidity and flexibility to the branches.
(e) The husk of the coconut tree is composed of sclerenchyma tissue. Cells of the sclerenchyma tissue are hard due to the deposition of lignin in the cell walls. Due to this, it is difficult to pull out the husk of a coconut tree.
Page No 47:
Question 53:
List the characteristics of cork. How are they formed? Mention their role.
Answer:
The characteristics of cork are:
- After maturation the cork cells become dead.
- They are arranged compactly. Thus lack intercellular spaces.
- It has several layers thick cells.
- The walls of cork cells are thickened with suberin and due to this, the cork cells are impervious to water and gases.
Role of cork:
- It provides protection to plants.
- Due to the deposition of suberin, it is impervious to gases and water.
Page No 47:
Question 54:
Why are xylem and phloem called complex tissues? How are they different from one other?
Answer:
| Xylem | Phloem |
| 1. It consists of tracheids, vessels, xylem parenchyma, and xylem fibers. | 1. Phloem is made up of sieve tubes, companion cells, phloem fibres and the phloem parenchyma. |
| 2. It helps in the transport of water and minerals dissolved in it. | 2. It helps in the transport of food. |
| 3. Flow is unidirectional. | 3. Flow is bidirectional. |
| 4. All components of the xylem are dead except xylem parenchyma. | 4. All components of the phloem tissue are live except phloem fibre. |
Page No 47:
Question 55:
(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.
Answer:
(a)
| Meristematic tissue | Permanent tissue |
| (i) They are actively dividing cells. | (i) Cells of permanent tissue have lost the capacity to divide. |
| (ii) The cells are undifferentiated. | (ii) The cells are differentiated. |
| (iii) They are of three types- apical, intercalary, and lateral meristem | (iii) They are of two types- simple (parenchyma, sclerenchyma, and collenchyma) and complex tissue (xylem and pholem). |
(b) The loss of division ability of cells by taking up a permanent shape, size and function is called differentiation. The cells develop into tissues and organ by the process of differentiation.
(c) Simple permanent tissue- parenchyma tissue and sclerenchyma tissue.
Complex permanent tissue- xylem and pholem tissue.
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