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Adipose tissue stores fat and since fat is a bad conductor it acts as an insulator and prevents loss of heat from the body. Therefore, a fatty person is less affected by cold.

All other options given are in no way related to cold insulation. 

Therefore, option (c) is the correct answer

The parenchyma cells associated with phloem are called phloem parenchyma. They store starch and fats.

The fibres of Sclerenchyma associated with the xylem are known as xylem fibres. They give additional mechanical strength to the plant. They are also called wood fibres.

Sieve elements are the conducting elements of the phloem. Sieve elements are of two types – sieve cells and sieve tubes.

Sieve cells are present in Pteridophytes and Gymnosperms where as sieve tubes are present in Angiosperms.

Types of Epithelium:

(a) Squamous epithelium : Also called pavement epithelium. 

• Cells arranged end to end like tiles on a floor.

• Cells are polygonal in surface view. 

• It forms the delicate lining of cavities (mouth, oesophagus, nose, pericardium, alveoli etc.) blood vessels and covering of the tongue and skin. 

• Epithelial cells are arranged in many layers (stratum) to prevent wear and tear in skin. This pattern is stratified squalors epithelium. 

(b) Cubical epithelium : 

• They are cube like cells that fit closely, cells look like squares in section, but free surface appears hexagonal. 

• It is found in kidney tubules, thyroid vesicles & in glands (salivary glands, sweat glands). 

• It forms germinal epithelium of gonads (testes & ovaries). 

• It involves in absorption, excretion & secretion. It also provides mechanical support.

(c) Columnar epithelium : 

• Columnar means ‘pillar-like’ epithelium. It forms lining of stomach. 

• Small intestine & colon, forming mucous membranes. 

• Border of micro villi is present at the free surface end of each cell which increases absorption efficiency in small intestine. 

(d) Ciliated epithelium : 

• Cells may be cubical or columnar. 

• On its free surface are present protoplasmic outgrowths called cilia. 

• It helps in the movement of ova in the fallopian tube.

Phloem conducts food materials from leaves to the other parts of the plant. It is made up of four types of cells.

1. Sieve elements

2. Companion cells

3. Phloem fibres

4. Phloem parenchyma

1. Sieve elements

Sieve elements are the conducting elements of the phloem. Sieve elements are of two types – sieve cells and sieve tubes.

Sieve cells are present in Pteridophytes and Gymnosperms whereas sieve tubes are present in Angiosperms.

2. Companion cells 

Companion cells are thin walled elongated specialized Parenchyma cells. They are associated with sieve elements. They have a prominent nucleus and cytoplasm. They help the sieve tube in conduction of food materials in angiosperms.

3. Phloem fibres 

The fibres of sclerenchyma associated with phloem are called phloem fibres. They are also called bast-fibres. They give mechanical support to the plant. Among the four types of phloem cells, phloem fibres are the only dead tissues.

4. Phloem parenchyma

The parenchyma cells associated with phloem are called phloem parenchyma. They store starch and fats.

EPITHELIAL TISSUE 

• Always grows on some other types of tissue. 

• Cells of epithelium are set very close to each other and the tissue rests on a non-cellular basement membrane. 

• Consists of single layer of cells. 

• Blood vessels are absent and non-nervous in nature. 

• It covers all the organs and lines the cavities of hollow organs like stomach. 

• It is primarily protective in function.

Tracheary elements are dead, hollow cells with patterned cell walls comprising xylem vessels and tracheids, which function as conductive hollow tubes for water and nutrient transport throughout the plant body. Xylem fibre cells, with evenly thickened secondary cell walls, provide mechanical support to the plant body.

Sclerenchyma cells are elongated, dead cells with lignin deposits in their cell wall. They have no intercellular gaps. Sclerenchyma is found in the covering of seeds and nuts, around the vascular tissues in stems and the veins of leaves. Sclerenchyma provides strength to the plant. The main function of sclerenchyma is to provide mechanical support and protection to the plant.

Phloem : They also consist of both parenchymatous and schlerenc- -hymatous cells.

Phloem consists of four types of element : 

(i) Sieve tubes : 

• Sieve tubes are slender tube like structures made up of elongated, thin walled cells placed end to end. 

• The end walls of sieve tube cells are perforated by numerous pores, called as sieve plates. 

• Nucleus of sieve cell degenerates at maturity. However, cytoplasm persists, because of protoplasmic continuation of sieve tube with companion cell through plasmodesmata. • Sieve cells possess slime protein or protein which is concerned with growth and repair of sieve cells. 

(ii) Companion cells : 

• Companion cells have dense cytoplasm and prominent nuclei. 

(iii) Phloem fibre : 

• They give mechanical support to sieve tubes. 

(iv) Phloem parenchyma : 

• They store food and help in radial conduction of food.

Phloem is a living tissue in vascular plants which conducts the soluble organic compounds synthesized during photosynthesis downwards from the leaves. 

The constituents of phloem are: 

• Companion cells – it appears to check the activity of the adjacent sieve element and participates in loading and unloading of the sugar into the sieve element 

• Sieve tubes – these elongated living cells, conveys carbohydrates, chiefly sucrose from leaves to roots and fruits 

• Phloem fibres – they are commercially useful as they possess great pliability and tensile strength 

• Phloem parenchyma – also known as transfer cells, they are found near the finest branches, ends of sieve tubes in leaf veinlets, functional here in conveying food

Xylem is mainly concerned with the transport of nutrients, water and minerals upwards in the plant body. It forms a continuous tube through the roots, stems, leaves, flowers and fruits by the fusion of elongated cells.

It is composed of different kinds of cells namely,

1. Tracheids

2. Xylem vessels.

3. Xylem fibres

4. Xylem parenchyma.

1. Tracheids are elongated, tapering cells with blunt ends. They have lignified secondary wall. They are the chief water conducting elements in Pteridophytes and Gymnosperms. 

2. Xylem vessels 

Xylem vessels have perforations at the end and are placed one above the other like a long pipe line. They are seen in the xylem of angiosperms. They conduct water, mineral nutrients and also provide mechanical strength to the plant body. 

3. Xylem Fibres 

The fibres of Sclerenchyma associated with the xylem are known as xylem fibres. They give additional mechanical strength to the plant. They are also called wood fibres.

4. Xylem Parenchyma 

The parenchyma cells associated with xylem are known as xylem parenchyma. It is the only living tissue amongst xylem cells. They store food reserves in the form of starch and fat. They also help in conduction of water.

It is a dead tissue. The cells are thick with lignified walls. They give mechanical support to the organs. 

This has two types of cells – 

(i) Sclereids and 

(ii) Fibres.

(i) Sclereids

Sclereids are stone cells which are commonly found in shells of the nut, pulp of certain fruits such as Pear and Sapota.

(ii) Fibres

The fibres are elongated strands with simple pits throughout its length.

Sclereids are stone cells which are commonly found in shells of the nut, pulp of certain fruits such as Pear and Sapota.

(a) Tissue that forms the inner lining of our mouth is epithelial tissue. It forms a barrier to keep different body systems separate. 

(b) Tissue that stores fat in our body. Adipose tissue, it stores excess fat in the body found abundant in the abdomen and in the hip. 

(c) Tissue that transports food in plants. Xylem is a complex permanent tissue. It conducts water from roots to the different parts of a plant.

(i) Ligaments connects bone to bone in humans. 

Following are the characteristic features of the ligament: 

● Ligament is very elastic and flexible in nature. 

● It is of considerable strength. 

● It contains very little amount of matrix. 

(ii) Simple squamous epithelium forms the inner lining of the alveoli. 

Following are the characteristic feature of the simple squamous epithelium: 

● The cells are extremely thin and delicate. 

● It forms a delicate, lat and thin lining. (iii) Cell wall has the prominent middle lamella. Features of the middle lamella: 

● Middle lamella cements the two cell walls. 

● It is found between the cell wall of fruits also. 

● It is composed of cellulose, hemicelluloses and pectin. 

(iv) Xylem components tracheids and vessels transport the water and minerals in the plants.

Following are the characteristic feature of the xylem tracheids and vessels: 

● Tracheids and vessels are dead elements of xylem. 

● They have thick walls and are tubular structures. 

● Tracheids and vessels provide unidirectional low of water and minerals

PERMANENT TISSUE 

• The permanent tissues are composed of those cells which have lost their capability to divide. 

• They have definite shape, size and thickness. The permanent tissue may be dead or living. 

• The division & differentiation of the cells of meristematic tissues give rise to permanent tissues. 

• In cell differentiation, developing tissue and organs change from simple to more complex forms to become specialized for specific functions. 

• The cells of permanent tissue loose the capacity to divide and attain a permanent shape, size and function.

Depending upon the Structure and Composition, the Permanent tissues are classified into two types : 

(A) Simple Permanent Tissues

(B) Complex Permanent Tissues

Parenchyma : It is the fundamental tissue. 

• Tissue first time evolved in bryophyte. 

• Thin walled cells, oval or spherical in structure. 

• Cell wall mainly composed of cellulose & pectin. 

• Large central vacuole for food & water storage. 

• Primary function is food storage.

• Some parenchyma involved in excretory substance storage are so called as idioblast, storing such as resin, tannin, gums & oils. 

• In typical parenchyma chlorophyll is absent. 

• Chloroplast containing parenchyma tissue are chlorenchyma which perform photosynthesis e.g., mesophyll of leaves. 

• In hydrophytic plants aerenchyma (a type of parenchyma containing air spaces) provides buoyancy. 

• Parenchyma provides turgidity to cells.

Collenchyma : It is the living mechanical tissue.

• Elongated cells with thick corners. 

• Localized cellulose & pectin thickening. 

• Provides flexibility to plant parts & easy bending of various parts of plant. 

• Present only in herbaceous dicot stem. 

• Present at thin margin of leaves. 

• Few chloroplasts may be present. 

• Gives mechanical strength & elasticity to the growing stems.

Sclerenchyma : (Scleras – hard) Strengthening tissue.

• Composed of extremely thick walled cells with little or no protoplasm. 

• Cells are dead & possess very thick lignified walls. 

• Lignin is water-proof material. 

• Intercellular spaces are absent.

Smooth muscles are also called as unstriated muscles because smooth muscles do not exhibit any kind of alternate bands, striations on them. Therefore, they are called unstriated muscles.