TISSUE Tissues Levels of Organisation +A tissue is a group of cells having a common origin, similar structure and function and held together by a cementing substance. Example: Connective tissue Different types of tissues working together and contributing to specific functions inside the body constitute an organ. Example: Stomach “Different organs coordinate to perform a specific life process and form an organ system. Example: Digestive system “Various organ systems working simultaneously together constitute an organism. Example: Plants Differences between Plant and Animal Tissues . Dead supportive tissues are more Living supportive tissues are more abundant as compared to living abundant as compared to dead tissues. tissues. 2._Require less maintenance energy. 2. Require more maintenance energy. 3. Differentiation of meristematic and 3. No differentiation of meristematic and permanent tissues. permanent tissues. Organisation is simple Organisation is relatively comple: 5. Tissue organisation is meant for 5. Tissue organisation is meant for high stationary habit of plants. mobility of animals.BIOLOGY Classification of Plant Tissues TISSUE. Meristematic tissue 1 Permanent tissue v ¥ ¥ + Basod on Protecve issue Supporting issue Conducting issue postion in plant an rn Parenchyma Collenchyma Sclerenchymma Avical Intercalary Lateral stom meristem ersten Epidermis 7 Xylem Promeristom / Primary Secondary Primordial meristem meristem soadstem Meristematic Tissue *Cells are thin-walled and composed of *Located at the tips of the roots and stems, and the base of the node, internode or leaf. cellulose. ‘Types of Meristematic Tissues ‘The cells of meristematic tissue divide actively, which results in‘ growth (increase in thickness and length) of plants. Apical meristem | Located at the growing points of the stem, roots, branches and in growing young leaves near the tips of stems and axillary buds Enables the root and stem to grow by increasing the length of plants intercalary Located at the internodes or stem regions The cells are active and they meristem between the places at which the leaves attach | continuously form several new and at leaf bases cells Lateral Present laterally (on the sides) on the roots and | The girth and meristem’ stem and is situated parallel to the longitudinal width/diameter/thickness of the Cambium axis below the bark stem or root increases because of the lateral meristemTISSUES Permanent Tissues + Permanent tissues are formed by the division of the meristematic tissue cells which have lost their ability to multiply. ‘Types of Permanent Tissues Protective Tissue * Itis found on the surface of the roots, stems and leaves. * It consists of cells with thick walls. * It provides protection against mechanical injury or invasion by parasitic fungi. Types of Protective Tissues vacuolated protoplasts. Type Characteristics Location Function Epidermis | Cells are elongated and Present in the outermost Protects the plant from flattened with no intercellular layer of leaves, flowers, desiccation and spaces between them. stem and roots. infection. Cork Cells are rectangular with Itis the outermost layer formed after the epidermis undergoes certain changes. Prevents desiccation, infection and mechanical injury. Supporting Tissue * It provides support to the plant. Parenchyma Consists of relatively non- | Mainly present in the soft | Provides temporary specialised large, thin-walled | parts of the plant and outer | support and maintains living cells cortical region of roots and the shape of the plant stems body Collenchyma | Cells are living and elongated | Located in non-woody Provides mechanical with cell walls irregularly plants, leaf stalks and support and elasticity to thickened at the corners below the epidermis of the | young dicotyledonous stems and veins of leaves _| plants ‘Sclerenchyma | Consists of elongated, narrow | Located in the stems Provides strength and and fibre-like cells. around the vascular bundle, | toughness to plant parts Cells are dead, pointed at _| veins of leaves and hard both ends and thickened covering of seeds and nutsTISSUE Conducting Tissue (Vascular Tissue) * Itis present in stems, roots and leaves. * It provides a passage for water and dissolved materials to move up and down in the plant body. Types of Conducting Tissues Type Characteristics Location Function Xylem ‘Complex permanent tissue Present in the stem, roots | Provides upward with thick-walled cells; most of | and leaves movement of water and the cells are dead dissolved materials Components of Xylem Tracheids | Made of elongated cells with | - Provide a network of flat and tapering ends hollow and connected cells for the transport of water Xylem vessels | Tubular structures which - Allow free flow of water consist of dead cells and minerals from the roots to the leaves Xylem Consists of ving parenchyma | - ‘Stores food in the plant parenchyma _| cells associated with xylem body ‘Xylem fibres _ | Separated by thin cross walls | - Mainly support the plant Types of Conducting Tissues Type Characteristics Location Function Phloem Complex permanent tissue | Lies just beneath the bark _| Provides a passage for of the tree the downward movement of food Components of Phloem Sieve tubes | Tubular cells with perforated | - Translocation of organic walls and arranged end to end substances Companion Cells are living and keep their | - Help to control the cells nuclei and other organelles activity of sieve tube throughout their life elements Phioem fibres | Elongated, tapering and dead | Found particularly in the | Provide mechanical cells with thickened cell walls _| stem strength to plants Phioem Cells are alive and filled with | - Transports food from the parenchyma | cytoplasm leaves to the other non- green parts of the plantsTISSUES Differences between Meristematic and Permanent Tissues 1. Simple tissue 1. Simple, complex or specialised tissue 2. Component cells are small, 2. Component cells are large, spherical or polygonal and differentiated with different shapes undifferentiated 3._Intercellular spaces are absent 3._Intercellular spaces are present 4. Cells grow and divide regularly 4. Cells do not divide 5. Metabolically active 5. Metabolic rate is slow 6. Provides growth to the plant 6. Provides protection, support, conduction, photosynthesis, storage Classification of Animal Tissues Tissue Muscular Tissue Striated ‘Aceolar issue Non-stiated Connective tissue proper Adipose tissue Cardiac tesue ‘Supportive connective Fluid connective tissue Fibrous tissue Cartlage Simple Straied —_Colurnar tiated Cuboidal Glandular squamous squamous epithelum columnar epithelium epithelium pihelum epithelium epithelium Epithelial Tissue lat, cuboidal or columnar cellsTISSUES ‘Types of Epithelial Tissues Simple | Cells are large, Lining of blood vessels, lung Transport of substances squamous | extremely thin and flat | alveoli, oesophagus, the lining of | through a selectively epithelium the mouth and cheek permeable membrane Stratified | Cells are arranged in| Outer protective covering all over _| Provides protection to squamous | a patter of layers _ the body surface underlying tissues epithelium Columnar | Celis are tall and Inner lining of the ‘Absorption of nutrients from epithelium | cylindrical-ike pillars __| stomach and intestines the digested food Ciliated | Cells possess fine | Inner lining of the trachea, lungs, _| In the respiratory tract, the columnar | hair-like cilia respiratory system and buccal movement of cilia pushes the epithelium chambers mucus forward to clear it Cuboidal | Celis are cube-shaped | Lining of the kidney tubules as well | Helps in the absorption of epithelium | andare placedona as in the ducts of the salivary useful material from urine basement membrane _| glands before it is passed out Glandular | Epithelial tissue which | Present in the stomach, intestine _ | Synthesis and secretion of epithelium | folds inwards to form | and pancreas substances at the epithelial a multicellular gland surface Connective Tissue *Consists of a matrix and the cells are embedded in it Types of Connective Tissues Connective Tissue Proper/Loose Connective Tissue * Itis composed of irregular cells scattered and embedded in a soft matrix and encompasses all internal organs and body cavities. * It acts as a binding and supporting structure within the body. +Found in the deeper parts of the body, between the skin and muscles *Connects various organs and keeps them in placeTISSUES Areolar_| Made of gelatinous matrix | Found between the skin and ‘Supports and strengthens the tissue | containing cells and muscles, around the blood internal organs irregularly arranged fibres | vessels, nerves and in the bone marrow ‘Adipose | Cells are filed with fat Found beneath the skin, around | insulates the body and tissue globules the kidneys and other internal prevents the loss of heat ‘organs such as intestines Fibrous | Mainly formed of fibre- | Found in the spaces between the | Tendons help to attach tissue forming cells, which form | bones and muscles muscles to the bones. the tendons and Ligaments serve to hold the ligaments. structures together and keep them strong and stable * It connects different tissues. Supportive Connective Tissue/Dense Connective Tissue * It is composed of fibres as its main matrix element and is found in bones and cartilages. ‘Types of Supportive Connective Tissues Type Characteristics Location Function Cartilage | Non-porous, semi- Present in the nose, external ear, | Smoothens the bone surface transparent and elastic _| trachea, larynx, ends of the long _| at joints, allowing smooth tissue bones and between the vertebrae | movement of these joints Bone | Hard, strong and non- _| Forms a rigid part of the skeletal _| Forms the supporting flexible porous tissue system framework of the body which consists of living Gives shape and rigidity to cells the body Fluid Connective Tissue * It consists of liquid as the ground substance and is present throughout the body. * It provides nutrition, helps in transport of nutrients and gets rid of waste matter. Types of Fluid Connective Tissues Type Characteristics Location Function Blood | Red-coloured fluid matrix which | Present throughout the | Connects different parts of consists of plasma and cells such | body the body and establishes as RBCs, WBCs and platelets continuity within the body Lymph | Fluid surrounding the body cells Present throughout the Transports nutrients and which contains WBCs body provides protection against diseasesTISSUE Muscle Tissue “Consists of elongated, narrow, muscle cells bones called muscle fibres *Mostly attached to the| | -Helps in contraction and relaxation of the body ‘Types of Muscle Tissues Type Characteristics Location Function Striated/skeletal’ | Muscle fibres are long, | Found attached to the Help in voluntary muscle striped/voluntary _| cylindrical, unbranched _| bones movement and locomotion muscles and multinucleate Non-striated/_ ‘smooth/non-striped/ involuntary muscles Muscle fibres are smooth and without striations. Found in the uterus, digestive tract, urinary bladder, irs of the eye, bronchi of the lungs and other internal organs Carry out movements which cannot be carried out by our conscious will Cardiac/heart muscles ‘Muscle cells are short, cylindrical and have a single, centrally placed nucleus Found only in the walls of the heart Rhythmic contraction and relaxation of cardiac muscles help to pump and distribute the blood to various parts of the body Differences between Smooth, Skeletal and Cardiac Muscles Contraction not inherent Contraction not inherent 1. Not striated 1. Striated 1. Striated 2. Spindle-shaped 2. Cylindrical 2. Cylindrical 3._Not branched 3._Not branched 3. Branched 4. Nucleus - central 4. Nuclei - peripheral 4. Nuclei - central 5. No discs 5. No discs 5. Intercalated discs 6._Involuntary 6. Voluntary 6._ Involuntary 7. Slow 7. Fast 7. Fast 8. 8. 8. Contraction inherent Nervous/Neural Tissue “Made up of elongated cells called neurons Each neuron consists of three parts—cell body, ‘axon and dendrites somponent of the nervous system and ‘encompasses the brain, spinal cord and nerves. versa Nerve cells mediate the transmission of messages from the brain to different pars of the body and vice