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1. Wooden stopper or cork is obtained from the phellem (cork) part of a bark. 

2. Phellem (cork) is impervious in nature and does not allow entry of water due to suberized walls. 

3. Due to this it does not rot and remains as it is for many years.

1. Small gateways in the epidermal cells are called as stomata. 

2. Stoma is controlled or guarded by specially modified cells called guard cells. 

3. These guard cells may be kidneyshaped (dicot) or dumbbell-shaped (monocot), collectively called as stomata. 

4. Guard cells have chloroplasts to carry out photosynthesis. 

5. Change in turgor pressure of guard cells causes opening and closing of stomata, which enables exchange of gases and water vapour. 

6. Stomata are further covered by subsidiary cells. 

7. Stoma, guard cells and subsidiary cells form a unit called stomatal apparatus.

1. In a dicot leaf, stomata are generally absent on upper epidermis but are present on lower epidermis. Thus, the student must have thought that he has placed slide upside down. 

2. According to teacher, the section was placed rightly, thus the given section must be of monocot leaf. 

3. It is because, in monocot leaf stomata are present on both upper and lower epidermis.

D) Hydrophytes

D) Preparation of food through photosynthesis

C) Guard cells

(i) C) Chlorenchyma

(ii) C) Schlerenchyma

Stele of the plant is responsible for transport of water, minerals and food materials.

D) Vascular tissue

D) all the above

A) Apical meristem

A) Meristematic tissue

Correct option is C) Stomata

Correct option is B) Phloem

Correct option is C) Q

C) move upwards

(C) lateral meristem

Collenchyma is a type of living tissue.

Parenchyma: 

1. It is a type of simple permanent tissue. 

2. Cells in this tissue are thin walled, isodiametric, round, oval to polygonal or elongated in shape. 

3. Cell wall is composed of cellulose. 

4. Cells are living with prominent nucleus and cytoplasm with large vacuole. 

5. Parenchyma has distinct intercellular spaces. Sometimes, cells may show compact arrangement.

6. The cytoplasm of adjacent cells is interconnected through plasmodesmata and thus forms a continuous tissue. 

7. This is less specialized permanent tissue. 

8. Occurrence: These cells are distributed in all the parts of a plant body viz. epidermis, cortex, pericycle, pith, mesophyll cells, endosperm, xylem and phloem. 

9. Functions: These cells store food, water, help in gaseous exchange, increase buoyancy, perform photosynthesis and different functions in plant body. 

10. Dedifferentiation in parenchyma cells develops vascular cambium and cork cambium at the time of secondary growth.

a. Simple tissue: 

1. They are made up of only one type of cells.

2. They are found in all the plant parts. 

3. They perform many functions. 

4. Simple tissues in plants are Parenchyma, Collenchyma, Sclerenchyma. 

b. Complex tissue: 

1. They are made up of many types of cells. 

2. They are found only in the vascular regions of the plant. 

3. They mainly perform the function of conduction of food and water. 

4. Complex tissues in plants are Xylem and Phloem.

A group of cells having essentially a common function and origin is called as tissue

Classification of meristematic tissue on the basis of origin:

1. Promeristem / Primordial meristem: 

a. It is also called as embryonic meristem. 

b. It usually occupies very minute area at the tip of root and shoot. 

2. Primary meristem: 

a. It originates from the primordial meristem and occurs in the plant body from the beginning, at the root and shoot apices. 

b. Cells are always in active state of division and give rise to permanent tissues. 

3. Secondary meristem: 

a. These tissues develop from living permanent tissues during later stages of plant growth hence are called as secondary meristems. 

b. This tissue occurs in the mature regions of root and shoot of many plants.

c. Secondary meristem is always lateral (to the central axis) in position 

e.g. Fascicular cambium, inter fascicular cambium, cork cambium.

1. It is possible that one of the cut logs was of a tropical tree, whereas the other was of a temperate tree. Since tropical trees grow in a similar manner all year, growth rings are not apparent. Another explanation for this could be that the log which had growth rings must be of an old tree which has experience many seasons, whereas the log without growth rings must be of younger tree, that has not been subjected to seasonal changes and hence not developed prominent growth rings.

2. Growth rings are formed due cambial activity during favourable and non-favourable climatic conditions. 

3. During favourable conditions, spring wood (early wood) is formed which has broader xylem bands, lighter colour, tracheids with thin wall and wide lumen, fibres are less in number, low density. Whereas, during unfavourable conditions, autumn wood (late wood) is formed which has narrow xylem band, darker in colour, lumen is narrow and walls are thick with abundant fibres, high density. 

4. Spring wood and autumn wood that appear as alternate light and dark concentric rings, constitute an annual ring or growth ring. 

5. These growth rings can be used to estimate the age of the tree. These are found more in older trees as compare to younger tree.

Xylem is a complex permanent tissue.

1. Vascular bundle of monocot and dicot root. 

2. Vascular bundle of monocot and dicot stem. 

3. Vascular bundle of monocot and dicot leaf.

Anatomy of dicot root: 

The transverse section of a typical dicotyledonous root shows following anatomical features: 

1. Epiblema: 

It is the outermost single layer of cells without cuticle. Some epidermal cells prolong to form unicellular root hairs. 

2. Cortex: 

It is made up of many layers of thin walled parenchyma cells. Cortical cells store food and water. 

3. Exodermis: 

After the death of epiblema, outer layer of cortex become cutinized and is called Exodermis. 

4. Endodermis: 

The innermost layer of cortex is called Endodermis. The cells are barrel-shaped and their radial walls bear Casparian strip or Casparian bands composed of suberin. Near the protoxylem, there are unthickened passage cells.

5. Stele:

It consists of pericycle, vascular bundles and pith. 

a. Pericycle: 

Next to the endodermis, there is a single layer of thin walled parenchyma cells called pericycle. It forms outermost layer of stele or vascular cylinder. 

b. Vascular bundle: 

Vascular bundles are radial. Xylem and Phloem occur in separate patches arranged on alternate radii. Xylem is exarch in root that means protoxylem vessels are towards periphery and metaxylem elements are towards centre. Xylem bundles vary from two to six number, i.e. they may be diarch, triarch, tetrarch, etc. 

Connective tissue: 

A parenchymatous tissue is present in between xylem and phloem. 

c. Pith: 

The central part of stele is called pith. It is narrow and made up of parenchymatous cells, with or without intercellular spaces. 

6. At a later stage cambium ring develops between the xylem and phloem causing secondary growth.

Anatomy of monocot stem:

 A transverse section of maize (monocot) stem shows the following structures: 

1. Epidermis: It is single-layered and without trichomes. 

2. Hypodermis: It is sclerenchymatous. 

3. Ground tissue: It consists of thin walled parenchyma cells. It extends from hypodermis to the centre. It is not differentiated into cortex, endodermis, pericycle and pith. 

4. Vascular bundles: Vascular bundles are numerous and are scattered in ground tissue. Each vascular bundle is surrounded by a sclerenchymatous bundle sheath. Vascular bundles are conjoint, collateral and closed (without cambium). Xylem is endarch and shows lysigenous cavity. 

5. Pith: Pith is absent.

Anatomy of dicot leaf:

1. Structure of dorsiventral leaf: The mesophyll tissue is differentiated into palisade and spongy parenchyma in a dorsiventral leaf. This type is very common in dicot leaf.

The different parts of this leaf are as follows: 

2. Upper epidermis: It consists of a single layer of tightly packed rectangular, barrel shaped, parenchymatous cells which are devoid of chloroplast. A distinct layer of cuticle lies on the outside of the epidermis. Stomata are generally absent. 

3. Mesophyll: Between upper and lower epidermis, there is chloroplast-containing photosynthetic tissue called mesophyll It is differentiated into Palisade parenchyma and Spongy parenchyma. 

a. Palisade parenchyma: Palisade parenchyma is present below upper epidermis and consists of closely packed elongated cells. The cells contain abundant chloroplasts and help in photosynthesis. 

b. Spongy parenchyma: Spongy parenchyma is present below palisade tissue and consists of loosely arranged irregularly shaped cells with intercellular spaces. The spongy parenchyma cells contain chloroplast and are in contact with the atmosphere through stomata. 

4. Vascular system: It is made up of a number of vascular bundles of varying size depending upon the venation. Each one is surrounded by a thin layer of parenchymatous cells called bundle sheath. Vascular bundles are closed. Xylem lies towards upper epidermis and phloem towards lower epidermis. Cambium is absent, hence there is no secondary growth in the leaf. 

5. Lower epidermis: It consists of a single layer of compactly arranged rectangular, parenchymatous cells. A thin layer of cuticle is also present. The lower epidermis contains a large number of microscopic pores called stomata. There is an air-space called substomatal chamber at each stoma.

Anatomy of monocot leaf:

1. It is single layered, present on both sides of the leaf. It consists of compactly arranged rectangular transparent parenchymatous cells. Both the surfaces contain stomata. Both the surfaces have a distinct layer of cuticle. 

2. Mesophyll: Mesophyll is not differentiated into palisade and spongy tissue.

3. Vascular bundle: These are conjoint, collateral and closed.

Mesophyll tissue is present in leaf.

1. Cut portions of large tress show distinct rings which are annual rings formed due to activity of cambium during favourable and non-favourable climatic conditions. 

2. Kashmir falls under temperate region where the climatic conditions are not uniform through the year. In the spring season, conditions are favourable due to which cambium is active, whereas in autumn season, conditions are unfavourable due to which cambium is less active. This leads to formation of spring wood and autumn wood that appear as alternate light and dark concentric rings, constitute an annual ring or growth ring. 

3. Maharashtra falls under tropical region where climatic conditions are favourable throughout the year. In tropical areas, continuous growth of secondary xylem occurs. Thus, trees growing in tropical regions show less or no annual rings as compared to trees in temperate region.

1. Students must have observed monocot stems. 

2. It is because, monocot stem shows scattered vascular bundles. 

3. In monocot stem, vascular bundles are closed i.e. without cambium. 

4. Thus, secondary growth does not occur which is required for increase in girth. Hence, in spite of having large number of scattered vascular bundles, monocot stems do not grow in girth.

1. The pink coloured solution given by teacher must be a saffanin stain.

2. Saffanin is used to stain plant tissues, especially lignified tissues such as cell wall and xylem.

A) Onion cells has cell wall and cell membrane

D) Nehamiah Grew

B) Cells are arranged in circular

Meristematic Tissues:

1. Group of cells that are preparing to divide or are in continuous state of division or have the capacity to
   divide.
2. In early embryonic stages all the cells are meristematic in nature but later on this activity of diyison get restricted to certain specific regions called meristem (meristem means = divisible).
3. Meristemetic tissue are found in growing regions of plants and plants grow by these tissue.

(A) Based on origin and method of development meristems are of following three types.

1.Promeristem (= primordial meristem) –

• A group of cells originate from embryo end therefore called primordial or embryonic meristem.
• These tissue cells represent primary stages of meristemetic cells.
• These tissue are present in a small region at the apices of shoots and roots.
• Promeristem give rise to primary meristem.

2. Primary Meristem –

• The meristematie cells that originate from promeristem are primary meristems.
• These cells are always in active state of division and give rise to primary permanent tissues.
• They are present below the promeristem at shoot and root apices, at the apex of leaves and in intercalary parts.
• Protoderm (produces epidermal tissue system), procambium (produces primary vascular elements) ground meristem (produces cortex and pith) are kinds of primary meristem.

3. Secondary Meristem –

• They originate from primary permanent tissues.
• They do not have their own promeristem.
• Develop at a later stage and give rise to secondary permanent tissues.
• The cambium of root, vascular cambium (from interfascicular regions in dicots when secondary growth is needed and as cork cambium when formation of periderm and healing of wounds is needed.

D) both a, b correct

The term xylem (Greek, xylos = wood) was introduced byNageli (1858). Chief conducting tissue of vascular plants responsible for conduction of water and inorganic solutes.

Components of Xylem
(i) Tracheids :
Tracheids are elongated tube like dead cells (without protoplasm) with tapering ends (tangenital section)
They appear elongated (tangenital section) rectangular or somewhat rounded (radial section), angular or polygonal (cross section) but in some cases they may appear rounded. The walls are hard and lignified but not much thick and enclose a wide empty lumen. The tracheids are long but not as long as fibres. They reach up to 1 mm in length (in some plants they may attain a length of 12 cm or more).

The tracheids of primary xylem developes from pro-cambium whereas those of secondary xylem developes from vascular cambium. In the beginning these cells possess living protoplasm but due to lignification and deposition of thickening materials in wall they become dead at maturity.

Wall thickenings in Tracheids :
Tracheids possess various types of wall thickenings viz – annular, spiral, scalariform, reticulate and pitted. The protoxylem tracheids have annular (ring-.like) and spiral (helical) thickenings. The metaxylem and secondary xylem tracheids have scalariform (ladder like), reticulate (network) and pitted thickenings. The pits are of two types simple or bordered. The size and number of pits vary greatly in each tracheid.

Functions of Tracheids:

1. To conduct water and dissolved mineral elements from roots to the leaves. They are structurally adapted to their specific function.They are placed one above the other and also parallel to the long axis. The end walls are perforated by the presence of bordered pits which permit flow of water from one cell to another.
2. Also provide mechanical support due to presence of hard and firm secondary walls.

Correct option is C) Phloem

A) Dermal layer

Correct option is D) 3 only

(d) Companion cells

I will ask the following questions to know more about xylem and phloem.

1. What is the economic importance of xylem and phloem?

2. What are the factors that are helpful to vascular tissue in conducting water? 

3. How do plants get water in the higher mountains? 

4. What is the commercial importance of bast fibres?

D) All the above

(b) Epidermis

A) Trachieds

Vessels are found in xylem helps in conduction of nutrients. They also give mechanical support to the plant.

Vascular bundles: Stands for one of a number of strands of primary vascular tissue having both xylem and phloem.

Vascular tissues are the xylem and phloem.

Vascular tissues are involved in transportation.