Lecture 2 (tissues) PDF

LECTURE - 2 (TISSUES ) Outermost layer found in cell envelope of bacteria: Glycocalyx : I Bacterial cell wall: Peptidoglycan / Plasmid DNA function: to confer certain unique phenotypic characters to bacteria C /...

LECTURE - 2 (TISSUES ) Outermost layer found in cell envelope of bacteria: Glycocalyx : I Bacterial cell wall: Peptidoglycan / Plasmid DNA function: to confer certain unique phenotypic characters to bacteria C / Role of ribosomes of a polysome is to translate mRNA into proteins Peroxisomes: oxidative crystals SS I Cell that isdete aloe void in shape: White blood cell (has irregular shape) amoeboid Transcription: the process of the flow of genetic information from DNA to RNA Nucleus was discovered by Robert Brown Cell Cycle R A - Mitosis (cell division) RM PA W DNA synthesis  Major microtubule-organizing centre (MTOC) in eukaryotic cells = involved in various cellular process, including sensory reception, locomotion, and embryogenesis: Centrosome Cell theory that proved the quasi-fluid nature of lipids to enable C lateral movement of proteins within the bilayer: Fluid Mosaic Model Protein that protects epithelial cells from damage: Keratin SS Tissues group of cells that have similar structure combined together to perform a specific function forms a tissue R Tissues A plant tissues animal tissues RM Importance Causes division of labour in multicellular organisms Decreases workload on individual cells - Leads to organisation PA Basic Unit of Life -> Cell Group of cells -> Tissue Group of tissues - Organs Group of organs Organ System Group of Organs E Organism System  Plant tissue it C Meristematic tissue Permanent tissue - SS occurrence: growing regions of plants - when cell lose the ability to (root, shoot, etc) divide, by the process of shape: spherical, oval or rectangular differentiation, the take a Intercellular spaces: absent permanent shape, size and Vacuoles: absent function Active cells - Structure: large central vacuoles Cytoplasm: dense Cell wall: cellulose Nuclei: prominent Cell division R j · Cell wall in thin/thick Function: - protection A - Support > Storage - Photosynthesis RM I ⑳8 ④ ④ -I Tips of roots and shoots Nodes PA I Sideways growth = ↓ Height growth: Apical and intercalate Width growth: Lateral Types Types of Permanent Tissue - - Lateral Intercalary Apical - - - - Simple Tissue - Present beneath the I Present at the base of ~ Present at shoot ~ Complex Tissue bark leaves/internodes and root apex / Increase girth of root - Increase length of - Increase in length or stem leaves and internodes of root and stem  Simple Tissue - > Types mechanical tissue - - I a) Collenchyma Tissue - Occurrence: in leaf stalks and stem of dicots C - Cell Structure - I Living SS I Elongated / Irregularly thickened at corners I Very little intercellular space Functions e ↑ Provides mechanical strength and flexibility S Allows bending of parts ex: tendrils and stems of climbers R A b) Parenchyma Tissue - Aerenchyma - Functions - Chlorenchyma - Food storage tissue RM - · In some cases contains chlorophyll, called Chlorenchyma When loosely packed, intercellular airy spaces I are present called Aerenchyma Provides buoyancy to parts, helps them float PA @°@° c) Sclerenchyma Tissue > - - Dead cells - Provides toughness to the tissue Occurrence: Outer parts - eg: bark, husk of coconut , veins of leaves - Walls are thick - > Lignin  Protective Tissue (part of simple tissues) - Types: EEpidermis C Cork a) Epidermis Cuticle · SS - I Occurrence: Outermost layer of plant parts - eg: leaves, flowers, stem and roots Functions: - Protects all parts of plants cactus plant I W Prevents water loss - W R Plants of dry habitats have thicker epidermis Epidermal cells on the aerial parts of plant secrete waxy secretions which prevents from: A I - Water loss Injury RM Fungi infection W Plants growing in desert have cuticle I Layer of cutin is called cuticle Cutin is waxy materials and water resistant : W Cuticle aids in protection against water loss, injury and invasion of fungi Epidermal cells of the roots form hair like structures PA Long hair like parts increase absorption surface area of roots In leaves, epidermal cells form stomata ↑ Stomata are guarded by guard cells which are kidney shaped and regulate gaseous exchange Guttation: the process of planting axis External protective tissue liquid from its leaves or blades Dead Types Hydathode: a plant organ responsible Compactly arranged cells for gat vascular plants - - Intercellular spaces absent b) Cork The process happens at night - - Walls have suberin - Occurrence: in mature roots and shoots -  Functions: - Protection to mature roots and shoots - Suberin regulate gaseous exchange and water passage C Complex Permanent Tissue - Made up of more than one type of cells SS - Function - Xylem - Transport water, minerals and food materials Types - I vascular tissues · Xylem ↑ Phloem R A Xylem - - Conducting tissue (one-way conduction) RM - Conducts water and minerals from roots to shoots Xylem Types: - Xylem parenchyma: food ! Phloem storage Living - Tracheids - Conducts food (two-way conduction) Vessels Xylem fibres /sclerenchyma · PA Phloem Types: - dead Sieve tubes Companion cells Phloem parenchyma: food storage Phloem fibers: rigidity and support ↳or Phloem Sclerenchyma  Animal Tissue ↓ V I I W ↓ Epithelial Muscular Connective Nervous C - - E E - - - Squamous Striated Areolar Cuboidal Smooth Adipose SS · Columnar Stratified Cardiac Skeletal Ciliated Fluid a) Epithelial > Tightly packed Characteristics R Covering/protective tissues of animal body ; cells form continous sheet A Function > - Forms lining of mouth and alimentary canal Protection to body from injury ,· t e infection and and damage damage ↑ Eliminates waste I Absorption of water and nutrients Types RM i) Squamous Epithelial Tissue ↳ ↑ Cells are extremely thin Types - - Cells are flat - Irregularly shaped a) Simple Squamous Tissue - - Single layer of cells PA - Forms delicate lining eg: mouth and oesophagus food pipe b) Stratified Squamous Tissue Cells are arranged in layers Prevent wear and tear eg: Skin  ii) Cuboidal Epithelial Tissue - Structure - - I Cube like Tall = wide : C Occurrence - ↑ Sweat glands ↑ Salivary glands SS ↑ Thyroid glands a Lining of Kidney tubules iii) Columnar Epithelial Tissue e n ↑ ↑ Structure - Pillar like cells Tall > Wide R A Occurrence - - - - Lining of intestine Lining of stomach, gallbladder RM - iii) iv Ciliated Epithelial Tissue - Structure - W Cuboidal/Columnar cells PA v Cells have hair like projections on free surface called “cilia”, which facilitates movement Occurrence - Respiratory tract. Urinary tubules or kidney Function Movement of mucus, urine, egg etc through rhythmic beating of cilia  b) Muscular Tissue/ Muscle Tissue - ↳Are elongated and Function - large sized Movement of body. ↳ - Contraction and Contractile protein relaxation C Types - - SS ↑ Cardiac muscle - Skeletal muscle - Smooth muscle a) Skeletal Muscle R - Muscle fibres are elongated and cylindrical A · Fast in nature Unbranched ↑ Each cell is multinucleated (many nuclei) RM I Striations are present (alternate dark and light bands - Easily fatigue Occurrence -- Biceps, bone Other names PA - ↳ Attached to skeletal: Skeleton Muscles I Striations are present: Striated Muscles I Are under our control: Voluntary muscles  b) Smooth/Visceral Muscles Uninucleated - > - Nucleus located at the centre of each cell · Striations are absent - Unbranched - C Slow W soft interior organs: Do not fatigue - lung, liver, abdomen, intestines - SS Other names - Found in visceral organs: Visceral Muscles Striations are absent: Unstriated muscles ↑ Not under our control: Involuntary Muscles · R Organs like; that have visceral muscles A RM Intestine Uterus Blood vessels PA Stomach Bronchi Iris  c) Cardiac Muscles - ↑ Fibres are cylindrical in shape - Each fibre is uninucleated ↑ Fibres are branched C - Striations are present - Do not fatigue SS Other names - · Cardiac muscle: only present in heart - Striated: Striations are present - Not under our control: Involuntary muscles Function - W Perform contraction and relaxation in wall of heart / R Help to pump and distribute blood to body A RM PA  c) Connective Tissue - Connects various body parts. Cells are embedded in an intracellular matrix Matrix may be jelly, fluid, dense or rigid C /1Y Cartilage Blood Bone SS R A Tendons Dermis RM PA Adipose Cartilage  Structure Cells + loose gel like matrix i Occurrence Types of Connective tissue - Between skin and muscles Around blood vessels and nerves a) Areolar Connective Tissue In bone marrow In space inside organs i) Loose Connective Tissue C Functions ii) Dense Connective Tissue Connects skin + muscles E Ligaments Fills the space inside the organs Supports internal organs SS Tendons Helps in repair of tissues b) Adipose Connective Tissue ii) Dense Connective Tissue ↑ - a) Tendons - Fibrous tissue R A - Great strength ~ Limited flexibility ~ Connects muscles to bones RM Muscle - Tendon - Bone W b) Ligaments - ↑ Considerable strength Bone Ligament Bone PA Little matrix is present - - - W Connects bones to bones. b) Adipose Connective Tissue - Structure - Aggregation of fat cells Cells are rounded/oval and contain large fat droplets  Occurrence fatty people have more Function - - Below the skin - adipose tissue Prevents body from mechanical : Bet internal organs n shocks Fat reservation Act as insulation Temperature regulation C c) Skeletal Connective Tissue - Types - SS - Cartilage - Bones I - - - 300 bones: child 206 bones: adult Longest bone: Femur (Thighs) Shortest bone: Stapes (Ear) i) Cartilage R A - Widely spaced out cells. Matrix is gel-like RM - Matrix is slightly elastic - Cartilage is flexible Occurrence - / Ear pinna, nose tip, trachea, larynx Smoothens bone surfaces at joints : Function PA - - Support and flexibility to body parts ii) Bones - Very strong - Non flexible Hard and rigid ↑ Matrix is hard and composed of calcium and phosphorous compounds  Functions - Forms a framework : Supports the body Provides shape to body Protects vital body organs like brain, lungs, etc. C I Layer: meningitis SS 22 bones in brain 8: cranial 14: facial d) Fluid Connective Tissue R A - Connects different part of the body Maintains a continuity RM Types E Blood Lymph i) Blood Function: transports gases, digested PA - - food, hormones, waste materials Blood 55% E / I ° 45% Liquid Solid / / - Plasma: E 90% water RBC WBC Platelets ~ Remaining:and 92% water proteins, hormones Protein, glucose, salts, 8% hormones, fats, V vitamins Yellow fluid  Solid - in RBC WBC Platelets ! - - C red in colour due Also known as leukocytes I Helps in blood to presence of heme (Fe) Prevent from infection, clotting Heme has high affinity provide our body a If suffering from SS towards oxygen defence mechanism dengue, it reduces Heme transports oxygen S Is formed in bone Also known as throughout the body to marrow thrombocytes carry out respiration to produce energy Types : No. of formation: 150-400K Life span: 7-10 days - Graveyard of RBC: Spleen Monocytes Shape: Biconcave; disc- Lymphocytes > T cells and B cells shaped Also known as erythrocytes R · Basophils Neutrophils Neutrophils Basophils Eosinophils > Granulocytes A - Time period of Shape: round/irregular RBC: 120 days End point: Spleen Life span: 12 days RM I - I No of formation: 4.5-6.5M ↑ No. of formation: 4000-10,000 Order in number: - - study of blood: hematology RBC > Platelets > WBCs PA ii) Lymph - Structure - Colourless fluid RBCs and Blood proteins are absent  d) Nervous Tissue - cell body - C SS Found in brain, spinal cord, nerves fundamental unit of kidney: Function R : Fundamental unit of nervous system: Neuron G Converts Chemical Energy to W · Nephron Study of kidney: Nephrology A - - Sense stimuli: Electrical Energy - ~ Touch Smell RM Taste Hearing Sight / PA Hair like structures receives signals from other neurons I Glial cells: far more numerous than neurons and unlike neurons, they are capable of mitosis  C A R I. SS - one neuron’s dendrite transmit information to other neuron’s cell body The gap bet these two is called synapse RM · Camel hump is made of: Adipose tissue PA