9, Biomolecules NCERT Notes For Class 11

Biomolecules NCERT Notes For Class 11 Download in pdf Chapter 9 Biomolecules Download in pdf

Chapter 9 Biomolecules

NCERT Notes For Biology Class 11 Download In PDF

POINTS TO REMEMBER

Biomolecules : All the carbon compounds that we get from living tissues.

Micromolecules : Molecules which have molecular weights less than one thou- sand dalton.

Amino acids : Organic compounds containing an amino group and one car- boxyl group (acid group) and both these groups are attached to the same carbon atom called ? ? ? ? ? carbon.

Lipids :
� Water insoluble, containing C, H, O.
� Fats on hydrolysis yield fatty acids.
� Fatty acid has a carboxyl group attached to an R group (contains 1 to 19 carbons).
� Fatty

Acids : Saturated With single bonds in carbon chain. e.g., Palmitic acid, butyric acid.

Unsaturated : With one or more double bonds. e.g., oleic acid, linoleic acid.

Glycerol : A simple lipid, is trihydroxy propane.

� Some lipids have fatty acids esterified with glycerol.
� They can be monoglycerides, diglycerides and triglycerides.

� Phospholipids are compound lipids with phosphorus and a phosphory- lated organic compound e.g., Lecithin .

Nucleoside : Nitrogenous base + Sugar e.g., Adenosine, guanosine.

Nucleotide : Nitrogenous base + Sugar + Phosphate group. e.g., Adenylic acid, thymidylic acid.

Nucleic acid : Polymer of nucleotides - DNA and RNA.

Biomacromolecules : Biomolecules with molecular weights in the range of ten thousand daltons and above; found in acid insoluble fraction. Lipids are not strictly macromolecules as their molecular weights do not exceed 800 Da but form a part of the acid insoluble pool.

Proteins : 
� Are polymers of aminoacids linked by peptide bond.
� Is a heteropolymer.
� For functions of proteins

(Refer Table 9.5, Page no. 147, NCERT, Text Book of Biology for Class XI. Structure of Proteins)

(a) Primary structure : Is found in the form of linear sequence of amino acids. First amino acid is called N-terminal amino acid and last amino acid is called C-terminal amino acid.

(b) Secondary structure : Polypeptide chain undergoes folding or coiling which is stabilized by hydrogen bonding. Right handed helices are observed. e.g., fibrous protein in hair, nails.

(c) Tertiary structure : Long protein chain is folded upon itself like a hollow wollen ball. Gives a 3-dimensional view of protein, e.g., myosin.

(d) Quaternary structure : Two or more polypeptides with their foldings and coilings are arranged with respect to each other. e.g., Human haemoglobin molecule has 4 peptide chains - 2a and 2b subunits.

Peptide bond : Formed between the carboxyl (-COOH) group of one amino acid and the amino (-NH ) group of the next amino acid with the elimination of water moeity.

2 Polysaccharides : Are long chain of sugars.

(a) Starch : Store house of energy in plant tissues. Forms helical second- ary structures.
(b) Cellulose : Polymer of glucose.
(c) Glycogen : Is a branched homopolymer, found as storage polysaccharide in animals.
(d) Insulin : Is a polymer of fructose.
(e) Chitin : Chemically modified sugar (amino-sugars) N-acetyl galac- tosamine. Form exoskeleton of arthropods.

Anabolic pathways : Lead to formation of more complex structure from a sim- pler structure with the consumption of energy. e.g., Protein from amino acids.

Catabolic pathway : Lead to formation of simpler structure from a complex structure. e.g., Glucose ? Lactic Acid.

Enzymes : Are biocatalysts.
� Almost all enzymes are proteins.
� Ribozomes - Nucleic acids that behave like enzymes.
� Has primary, secondary and tertiary structure.
� Active site of an enzyme is a crevice or pocket into which substrate fits.
� Enzymes get damaged at high temperatures.
� Enzymes isolated from thermophilic organisms (live under high temperatures) are thermostable.
� Enzymes accelerate the reactions many folds.
� Enzymes lower the activation energy of reactions.

(Fig. 9.6, Page no. 156, NCERT Text Book of Biology for Class XI).

� ES ES EP EP +??+ where E = Enzyme, S = Substrate, P = Product.

Factors affecting enzyme activity :
(a) Temperature : Show highest activity at optimum temperature. Activity declines above and below the optimum value.
(b) pH : Enzymes function in a narrow range of pH. Highest activity at optimum pH.

(Fig. 9.7, Page no. 157, NCERT, Text Book of Biology for Class XI)

(c) Concentration of substrate : The velocity of enzymatic reaction rises with increase in substrate concentration till it reaches maximum ve- ). Further increase of substrate does not increase the rate of reaction as no free enzyme molecules are available to find with additional substrate. locity

V max Enzyme inhibition : When the binding of a chemical shuts off enzyme activity, the process is called inhibition and chemical is called inhibitor.

Competitive inhibition : Inhibitor closely resembles the substrate in its molecular structure and inhibits the enzyme activity. E.g., inhibition of succinic dehydrogenase by malonate.

Classification of enzymes :

Oxidoreductase/dehydrogenases : Catalyse oxidoreduction between 2 sub- strates.

Transferases : Catalyse transfer of a group between a pair of substrates.

Hydrolases : Catalyse hydrolysis of ester, ether, peptide, glycosidic, C-C, P-N bonds.

Lyases : Catalyse removal of groups from substrates by mechanisms other than hydrolysis.

Isomerases : Catalyse inter-conversion of optical, geometric or positional isomers.

Ligases : Catalyse linking together of 2 compounds. Cofactors : Non-protein constituents found to the enzyme to make it cata- lytically active. Protein portion of enzyme is called apoenzyme.

Cofactors :
� Prosthetic groups : Are organic compounds tightly bound to apoenzyme. E.g., haem in peroxydase and catalase.
� Co-enzymes : Organic compounds which has transient association with enzyme. E.g., NAD, NADP.
� Metal ions : Required for enzyme activity. Form coordination bond with side chains at active site and with substrate.

E.g., zinc is a co-factor for enzyme carboxypeptidase.

18. Nucleic acids : Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). DNA structure (Watson and Crick Model) : DNA is a right handed, double helix of two polynucleotide chains, having a major and minor groove. The two chains are antiparallel, and held together by hydrogen bonds (two between A and T and three between C and G). The backbone is formed by sugar-phosphatesugar chain. The nitrogen bases are projected more or less perpendicular to this backbone and face inside.

8, Cell The Unit Of Life Class 11

Cell The Unit Of Life Class 11 Biology Notes Download in pdf Chapter 8 Cell - The Unit Of Life Download in pdf

Chapter 8 : Cell - The Unit Of Life

NCERT Notes For Class 11 Biology Download In PDF

POINTS TO REMEMBER

Gram positive bacteria : Bacteria that take up gram stain.

Gram negative bacteria : Bacteria that do not take up gram stain.

Prokaryotic cells : Cells which lack a well defined nucleus and membrane bound cell organelles. e.g., bacteria, cyanobacteria, mycoplasma.

Eukaryotic cells : Cells which have a well defined nucleus and membrane bound cell organelles. e.g., all protists, plants, animals and fungi cells.

Passive transport : Transport of molecules across a membrane along the con- centration gradient, i.e., from higher to lower concentration without the consumption of energy.

Active transport : Transport of molecules against concentrataion gradient, i.e., from lower to higher concentration with the consumption of energy (ATP).

Polyribosome/polysome : A chain like structure formed when several ribosome are attached to a single mRNA. PPLO : Pleuro Pneumonia Like

Organisms. Cell : Cell is the structural and functional unit of life. Cell Theory was formu- lated by Scheleiden and Schwann and was modified by

Rudolf virchow states :
(a) All living organisms are composed of cells and products of cells.
(b) All cells arise from pre-existing cells. Prokaryotic cells Genetic material is not enveloped by nuclear envelope.

Many bacteria contain extra chromosomal DNA ? plasmids. Cell Envelope Prokaryotic cells have a chemically complex cell envelope which consists of a tightly bound 3 layered structure i.e., outermost glycocalyx followed by cell wall and then plasma membrane.

A specialised structure ? mesosome is formed by the extension of plasma membrane into the cell. Mesosomes help in cell wall formation, DNA replication and distribution to daughter cells, respiration, secretion process, to increase surface area of plasma-membrane and enzymatic content.

Bacterial cells may be motile or non-motile. Motile bacterias have flagella composed of three parts ? filament, hook and basal body. Pili and fimbriae are surface structures which do not play any role in motality. These structures help the bacteria to attach with rocks and the host tissues.

70S ribosomes are associated with plasma membrane and is made of two subunits ? 50S and 30S. Ribosomes are site of protein synthesis.

Eukaryotic cells

Possess an organized nucleus with nuclear envelope and have a variety of complex locomotory and cytoskeletal structures. 

Cell Membrane

Singer and Nicolson (1972) gave �Fluid mosaic model�. According to this the quasi-fluid nature of lipid enables lateral movement of proteins within the overall bilayer

Functions : Selectively permeable.

Cell Wall is a non-living rigid structure which gives shape to the cell and protects cell from mechanical damage and infection, helps in cell-to-cell interaction and provides barrier to undesirable macromolecules.

Cell wall of algae is made of cellulose, galactans, mannans and minerals like calcium carbonate. Plant cell wall consists of cellulose, hemicellulose, pectins and proteins.

Middle lamella is made of calcium pectate which holds neighbouring cells together.

Plasmodesmata connect the cytoplasm of neighbouring cells.

Endoplasmic Recticulum (ER) Consists of network of tiny tubular structures. ER divides the intracellular space into two distinct compartments ? luminal (inside ER) and extra luminal (cytoplasm).

(i) Rough Endoplasmic Reticulum (RER) : 
� Ribosomes attached to outer surface.
� Involved in protein synthesis and secretion.

(ii) Smooth Endoplasmic Reticulum (SER) :
� Lack ribosomes.
� Site for synthesis of lipid.

Golgi apparatus : Consists of cisternae stacked parallel to each other. Two faces of the organelle are convex cis or forming face and concave trans or maturing face.

Functions : Performs packaging of materials, to be delivered either to the intra-cellar targets or secreted outside the cell. Important site of formation of glycoproteins and glycolipids.

Lysosomes : Membrane bound vesicular structures formed by the process of packaging in the golgi apparatus. Contain hydrolysing enzymes (lipases, proteases, carbohyrases) which are active in acidic pH. Also called �Suicidal Bag�.

Function : Intracellular digestion. Vacuoles : Membrane bound space found in the cytoplasm. Contain water, sap, excretory product, etc.

Function : In plants tonoplast (single membrane of vacuole) faciliates transport of ions and other substances. Contractile vacuole for excretion in Amoeba and food vacuoles formed in protistis for digestion of food.

Mitochondria : Double membrane structure. Outer membrane smooth and inner membrane forms a number of infoldings called cristae.

Function : Sites of aerobic respiration. Called �power houses� of cell as produce cellular energy in the form of ATP. Matrix possesses single circular DNA molecule, a few RNA molecules, ribosomes (70S). It divides by fission.

Plastids : Found in plant cells and in euglenoides. Chloroplasts, chromoplasts and leucoplasts are 3 types of plastids depending on pigments contained.Chloroplasts are double membraned structure. Space limited by inner membrane is called stroma. Flattened membranous sacs called thylakoids in stroma. Chlorophyll pigments are present in thylakoids.

Function : Site of photosynthesis. Ribosomes Compased of RNA and proteins; without membrane. Eucaryotic ribosomes are 80S.

Function : Site of protein synthesis. Cilia and Flagella Cilia are small structures which work like oar, which help in movement. Flagella are longer and responsible for cell movement. They are covered with plasma membrane. Core is called axoneme which has 9 + 2 arrangement. Centrosome and Centrioles Centrosome contains two cylindrical structures called centrioles. Surrounded by amorphous pericentriolar material. Has 9 + 0 arrangement. Centrioles form the basal body of cilia or flagella and spindle fibres for cell division in animal cells.

Nucleus : With double membrane; nuclear pores; has chromatin, nuclear matrix and nucleoli (site for rRNA synthesis).

Chromatin : DNA + non histone proteins. Chromosomes (on basis of position of centromere) : Metacentric : Middle centromere.

Sub-metacentric : Centromere nearer to one end of chromosome.

Acrocentric : Centromere situated close to its end.

Telocentric : Has terminal centromere.

Satellite : Some chromosomes have non-staining secondary constrictions at a constant location, which gives the appearance of small fragment called satellite.

7, Structural Organisation In Animals NCERT class 11

Structural Organisation In Animals NCERT Notes Download pdf Chapter 7 Structural Organisation In Animals Download in pdf

Chapter 7 : Structural Organisation In Animals

NCERT Notes For Class 11 Biology Download In PDF

POINTS TO REMEMBER

Tissue : A group of similar cells along with intercellular substances which perform a specific function.

Simple epithelium : is composed of a single layer of cells resting on a basement membrane.

Compound epithelium : consists of two or more cell layers and has protective function.

Areolar tissue : is a type of loose connective tissue present beneath the skin.

Adipose tissue : is a type of loose connective tissue which has cells specialised to store fats.

Neuroglia : A delicate connective tissue which supports and binds together the nerve tissue in the Central Nervous Tissue.

Malpighian tubules : Yellow coloured thin, filamentous tubules present at the junction of midgut and hindgut in cockroach; helps in excretion.

Uricotelic : Animals which excrete nitrogenous waste in the form of uric acid.

Tight junctions : Plasma membranes of adjacent cells are fused at intervals. They help to stop substances from leaking across a tissue.

Adhering junctions : Perform cementing function to keep neighbouring cells together.

Gap junction : Facilitate the cells to communicate with each other by connecting the cytoplasm of adjoining cells for rapid transfer of ions, small molecules and sometimes big molecules.

Compound

�Made of more than one layer of cells.
� Provide protection against chemical and mechanical stresses.
� Cover dry surface of skin, moist cavity, pharynx, inner lining of ducts of salivary glands and pancreatic ducts.

CONNECTIVE TISSUE

Loose Connective Tissue (has cells and fibres loosely arranged in semi-fluid ground substance)

(i) Areolar Tissue :
� present beneath the skin.
� contains fibroblasts, macrophages and mast cells.
� serves as a support framework for epithelium.

(ii) Adipase Tissue : 
� located beneath the skin.
� cells are specialised to store fats. Dense Connective Tissue Fibres and fibroblasts are compactly packed.

(i) Dense Regular :
� Collagen fibres present in rows.
� Tendons attach skeletal muscle to bone.
� Ligaments attach bone to bone.

(ii) Dense Irregular :
� Has collagen fibres and fibroblasts oriented differently.
� This tissue is present in the skin. Specialised Connective Tissue

(i) Cartilage made up of chondrocytes and collegen fibres.
(ii) Bones Ground substance is rich in calcium salts and collegen fibres Osteocytes are present in lacunae
(iii) Blood Fluid connective tissue, consists of plasma and blood cells Muscle Tissue Consists of long, highly contractile cells called fibres; bring about move- ment and locomotion.

(i) Skeletal Muscle :
� Consists of long cylindrical, multinucleated fibres.
� Closely attached to skeletal bones.
� Striated.

(ii) Smooth Muscles : 
� Consists of spindle like, uninucleated fibres.
� Do not show striations.
� Wall of internal organs such as blood vessels, stomach and intestine.

(iii) Cardiac Muscles :
� Short, cylindrical, uninucleated fibres.
� Occur in the heart wall.
� Intercalated discs for communication. Neural Tissue
� Neurons are the functional unit and are excitable cells.
� Neuroglia cells make up more than half the volume of neural tissue.

They protect and support neurons.

 Cockroach 

 Periplaneta americana is a terrestrial, nocturnal, omnivorous, unisexual, oviparous insect. Body covered by a chitinous, hard exoskeleton of hard plates called sclerites.

Head : Triangular, formed by fusion of 6 segments. Bears a pair of anten- nae, compound eyes. Mouth parts consists of labrum (upper lip), a pair of mandibles, a pair of maxillae, labium (lower lip), hypopharynx (acts as tongue).

Thorax : 3 segments; prothorax, mesothorax and metathorax.

Bears 2 pairs of wings : Forewings : tegmina (mesothoracic). Hindwings : transparent, membranous (metathoracic) and 3 pairs of legs in thoracic segments.

Abdomen : 10 segments. Bears a pair of long, segmented anal cerci in both sexes and a pair of short, unjoined anal styles in males only. Also has anus and genital aperture at the hind end. Genital aperture sur- rounded by external genitalia called gonapophysis or phallomere.

Anatomy : Study of the morphology of internal organs. Alimentary canal : Divided into foregut, midgut and hindgut.
Mouth ? Pharynx ? Oesophagus ? Crop (stores food) ? Gizzard (grind- ing of food) ? Hepatic caeca (at junction of fore and midgut; secretes digestive juice) ? Hindgut (ileum, colon, rectum) ? Anus.

Blood vascular system : Open type, visceral organs bathed in haemolymph (colourless plasma and haemocytes). Heart consists of enlongated mascular tube and differentiated into funnelshaped chambers with ostia on either side. Blood from sinuses enters heart through ostia and is pumped anteriorly to sinuses again. Blood colourless (haemolymph).

Repiratory system : Network of trachea which open through 10 spiracles. Spiracles regulated by sphincters. Oxygen delivered directly to cells. Excretion and osmoregulation by Malpighian tubules; uricotelic (Uric acid as excretory product).

Nervous system : Consists of series of fused segmentally arranged ganglia joined by paired longitudinally connectives on the ventral side. three ganglia in thorax, six in abdomen. Brain represented by supra-oesophageal ganglion.

Reproductive system : Male ? Pair of testes (4th-6th segments) ? vas deferens ? ejaculatory duct ? male gonophore. Glands ? Seminal vesicle (stores sperms), mushroom shaped gland (6th- 7th segment).

Female reproductive system : A pair of ovaries (with 8 ovarian tubules) ? Oviduct ? Genital chamberSperms transferred through spermatophores. Fertilised eggs encased in cap- sules called oothecae; development of P. americana paurometabolous (incomplete metamorphosis).

Nymph grows by moulting 13 times to reach adult form. Interaction with man
� Pests as destroy food and contaminate it.
� Can transmit a variety of bacterial diseases (Vector).

6, Anatomy Of Flowering Plants biology Class 11

Anatomy Of Flowering Plants biology Class 11 Notes Download in PD Chapter 6 Anatomy Of Flowering Plants Download in pdf

Biology Chapter 6 : Anatomy Of Flowering Plants

Notes For Class 11 Download In PDF

POINTS TO REMEMBER

Anatomy : Anatomy is the study of internal structure of organisms. Plant anatomy includes organisation and structure of tissues.

Tissue : A group of similar cells alongwith intercellular substance which perform a specific function.

Meristematic tissues : The meristematic tissue is made up of the cells which have the capability to divide. Meristems in plants are restricted to a specialised regions and responsible to the growth of plants.

Axillary bud : The buds which are present in the axils of leaves and are responsible for forming branches or flowers.

Permanent tissues : The permanent tissues are derived from meristematic tissue and are composed of cells, which have lost the ability to divide.

Collenchyma : It is formed of living, closely packed isodimetric cells. It�s cells are thickened at the corners due to deposition of cellulose and pectin. It provides mechanic support to the growing parts of the plant.

Sclerenchyma : It is formed of dead cells with thick and lignified walls. They have two types of cells : fibres and sclereids.

Xylem : Xylem consists of tracheids, vessels, xylem fibres and xylem parenchyma. It conducts water and minerals from roots to other parts of plant. Protoxylem : The first formed primary xylem elements. Metaxylem : The later formed primary xylem.

Endarch : Protoxylem lies towards the centre and metaxylem towards the periphery of the organ.

Phloem : Phloem consists of sieve tube elements, companion cells, phloem fibres and phloem parenchyma. Phloem transports the food material from leaves to various parts of the plant. Protophloem : First formed phloem with narrow sieve tubes. Metaxylem : Later formed phloem with bigger sieve tubes.

The Tissue System

1. Epidermal tissue system : It includes cuticle, epidermis, epidermal hairs, root hairs, trichomes and stomata.

2. The ground tissue system : It is made up of parenchyma, collenchyma, sclerenchyma. In dicot stems and roots the ground tissue is divided into hypodermis cortex, endodermis, pericycle, medullary rays and pith.

3. The vascular tissue system : It includes vascular bundles which are made up of xylem and phloem.

Secondary growth in dicot stem :

An increase in the girth (diameter) in plants. Vascular cambium and cork cambium (lateral meristems) are involved in secondary growth.

1. Formation of cambial ring : Intrafascicular cambium + interfascicular cambium.
2. Formation of secondary xylem and secondary phloem from cambial ring.
3. Formation of spring wood and autumn wood.
4. Development of cork cambium (phellogen)

(Phellogen + Phellem + Phelloderm) = Periderm

Secondary growth in dicot roots : Secondary growth in dicot root occurs with the activity of secondary meristems (vascular cambium). This cambium is produced in the stele and cortex, and results in increasing the girth of dicot roots.

5. Morphology of Flowering Plants Class 11 Notes

Morphology of Flowering Plants Class 11 Notes Download in PDF chapter 5 Morphology of Flowering Plants

Morphology of Flowering Plants
Class 11 Notes Download in PDF

Morphology:

The study of various external features of the organism is knownas morphology. �The angiosperms are characterized by presence of roots, stems, leaves, flowers and fruits.

The Root:The root is underground part of the plant and develops from elongation of radicle of the embryo. Various types of root
1.	Tap root: Originates from radicle. Dicotyledonous plantse.g., mustard,gram, mango.
2.	Fibrous root: Originates from base of the stem. Monocotyledonous plants e.g., wheat, paddy.
3.	Adventitious root: Originates from parts of the plant other than radicle. Banyan tree (Prop roots)Maize (Stilt roots)
Root Cap:The root is covered at the apex by the thimble-like structure which protects the tender apical part o the root.

Regions of the root:
1.	Region of meristematic activity		:		Cells of this region have the capability to divide.
2.	Region of elongation				Cells of this region are elongated and enlarged, responsible for root growth.
3.	Region of Maturation				Maturation:This region has differentiated and matured cells. Some of the epidermal cells o thi read-like root hairs for absorption of water and minerals.
Mo				f Root:
Roots are modified for support, storage of food, respiration.

Modifications of Root

�	For support	:		Prop roots in Banyan tree, stilt roots in maize and sugarcane.
�	For respiration	:		Pneumatophores in Rhizophora (Mangrove).
�	For storage of food	:		Fusiform (radish), Napiform (turnip), Conical (carrot).
The Stem		:		Stem is the aerial part of the plant and develops from plumule of the embryo.It bears nodes and internodes
Modifications of Stem				In some plants the stems are modified to perform the function of storage of food, support, protection and vegetative propagation

Modifications of Stem

�	For food storage	:		Rhizome (ginger), Tuber (potato), Bulb(onion), and Corm(colocasia).
�	For support	:		Stem tendrils of watermelon, pumpkin, cucumber.
�	For protection	:		Axillary buds of stem of Citrus, Bougainvillea get modifiedinto pointed thorns.
�	For vegetative propagation	:		Underground stems of grass, strawberry, lateral branches of mint and jasmine.
�	For assimilation of food	:		Flattened stem of Opuntia contains chlorophylland performs photosynthesis
Venation		:		The arrangement of veins and veinlets in the lamina of leaf.
The Leaf		:		Develops from shoot apical meristem, flattened, green structure, manufacture the food by photosynthesis. It has bud in axil. A typical leaf has leafbase, petiole and lamina.

Types of Venation:
1.	Reticulate	:		Veinlets form a network as in leaves of dicotyledonous plants(China rose, Peepal). Paralle
2.	Paralle	:		Veins run parallel to each other as in leaves of monocotyledonous plants (grass, maize).

Modifications of Leaves
�	Tendrils	:		(Climbing) ?Sweet wild pea
�	Spines	:		(Protection) ?Aloe, Opuntia, Argemone
	Fleshy	:		(Storage) ?Onion
�	Pitcher	:		(Nitrogen Nutrition) ?Nepenthes
The Inflorescence				The arrangement of flowers on the floral axis.
Main types of Inflorescence
1.	Racemose	:		Main axis is unlimited in growth-Radish, Mustard, Amaranthus.
2.	Cymose	:		Main axis is limited in growth-Cotton, Jasmine, Calotropis.
3.	Special type			Ficus, Salvia, Euphorbia.

Symmetry of flower	On the basis of no. of floral appendages	On the basis of position of calyx,corolla, androecium with respect to ovary
Actinomorphic (radial symmetry)	Trimerous	Hypogynous (superior ovary)
Zygomorphic (bilateral symmetry)	Tetramerous	Perigynous (half inferior ovary)
Asymmetric (irregular)	Pentamerous	Epigynous (inferior ovary)

1.	Calyx	:		Sepals, green in colour, leaf like.Gamosepalous? (Sepals united)Polyseppalous? (Sepals free)
2.	Corolla	:		Petals, usually brightly coloured to attract insects forpollinationGamopetalous? (Petals united)Polypetalous ? (Petals free)
Aestivation		:		The mode of arrangement of sepals or petals in floral bud with respect to other members of the same whore.
Types of aestivation

1.	Valvate	:		Sepals or petals do not overlap the sepal or petal at margins as inCalotropis.
2.	Twisted	:		Sepals or petals overlap the next sepal or petal as in China rose.
3.	Imbricate	:		margins of sepals or petals overlap one another but notin any definite direction as in Gulmohar.
4.	Vexillary	:		largest petal overlaps the two lateral petals which in turnoverlap two smallest anterior petals as in Pea. (Papilionaceous)
	Vexillary	:		If calyx and corolla are not distinguishable (tepals), they are called perianth
	Perianth
3.	Androecium	:		If calyx and corolla are not distinguishable (tepals), they are called perianth
4.	Gynoecium	:		Made up of one or more carpels, female reproductive part, consists of stigma, style and ovary, ovary bears one or more ovules. Carpels maybe apocarpous(free) or syncarpous (united). After fertilisation, ovules developinto seeds and ovary into fruit.
		Placentation : The arrangement of ovules within the ovary.
		Types of Placentation :
			Marginal : Placenta forms a ridge along the ventral suture of ovary as in pea.
			Parietal : Ovules develop on inner wall of ovary as in mustard.
				ree central : Ovules borne on central axis, lacking septa as in Dianthus.
		:		Basal : Placenta develops at the base of ovary as in sunflower.

The fruit : After fertilization, the mature ovary develops into fruit. The parthenocarpic
fruits are formed from ovary without fertilization.

Structure of a Dicotyledonous Seed:

Structure of a Monocotyledonous Seed:

Description of Some Important Families:

1.Fabaceae (Pulse Family)

2.Solanaceae (Potato Family)Floral formula: %��K₍₅₎ C1 + ₂ + ₍₂₎ A₍₉₎ + ₁ G₁

Floral formula: Br�� P3+3 A3+3 G(3)

Pdf chapter 4, Animal Kingdom Classification System Class 11

Animal Kingdom Classification System Class 11 Notes Download Pdf Chapter 4 Animal Kingdom

Animal Kingdom Classification System
Class 11 Notes Download Pdf

		1					Symmetry	:		Distribution of body parts around a
		2					hypothetical axis.	:		Ostia : Minute pores on body of sponge.
		3					Osculum	:		Large outlet in body of sponge.
		4					Hermaphrodite	:		Bisexual.
		5					Polyp	:		Sessile cylindrical form of coelenterate (Asexual).
		6					Medusa	:		Umbrella shaped free swimming sexual stage of coelenterate.
		7					Acoelomate	:		No coelom.
		8					Pseudocoelom	:		With false coelom (cavity not underlined by mesoderm).
		9					Dioecious	:		Unisexual.
		10					Operculum	:		Cover over gills in fish
		11					Notochord	:		Dorsal rod like bone
		12					Homoiotherms	:		Warm blooded.
		13					Bioluminescence	:		Emit light.
-Levels of organisation
		i)	Cellular level- loose cell aggregates, small division of labour eg. Sponges
		ii)	Tissues grouped into organs eg.
Coelenterate.
		iii)	Organ level-Tissues grouped into organs eg. Higher animals.
Circulatory system
		a)	Open type- No blood vessels, blood flows in sinuses.
		b)	Close type- Blood flows in closed vessels.
Symmetry
		-	Asymmetrical � No symmetry eg. Sponges.
		-
		-	Radial Symmetry � Any plane passing through central axis divides body in two equal halves.
		-	Bilateral Symmetry � Body can be divided into two equal halves through one plane only.
Diploblastic and Triploblastic organisation �
		-	Two embryonic layers � Ectoderm and Endoderm � Diploblastic.
		-	Three embryonic layers- Ectoderm, Mesoderm and endoderm- Triploblastic.
Coelom �
		-	Body cavity lined by mesoderm- True Coelom.
		-	Body cavity not lined by mesoderm Pseudo Coelom.
		-	No body cavity � Acoelomate.
Segmentation �
		-	True segments- Metameres (Body divided internally and externally).
Notochord �
		-	With notochord � Chordates.
		-	Without notochord � Non-Chordates.
	Classification of Animals �

Phylum Porifera �
		-	Marine.
		-	Multicellular, cellular grade body.�������
		-	Asymmetrical.
		-	Water canal system for food, respiration and excretion.
		-	Body wall with many pores � Ostia.
		-	Diploblastic.
		-	Water enters through Ostia and goes out through Osculum.
		-	Skeleton of spicules or spongin fibres.
		-	Hermaphrodite.
		-	Reproduction asexual by fragmentation and sexual by gametes.
		-	Fertilisation is internal, development indirect.
		-	eg. Sycon, Spongilla, Euspongiaetc.
Phylum Coelenterata (Cnidaria) �
		-	Aquatic (marine), Sessile or free living.
		-	Presence of Cnidoblasts or Cnidocytes � Stinging cells.
		-	Cnidoblasts are for defence, anchorage or predation.
		-	Tissue level body organisation.
		-	Diploblastic.
		-	Central gastro vascular cavity, single opening mouth.
		-	Two body forms � Polyp (Asexual), Medusa (Sexual) stage.
		-	eg Hydra, Physalia, Obelia, Aurelia etc.
Phylum Ctenophora (sea walnuts or comb jellies) �
		-	Marine, radial symmetry, Diploblastic, tissue grade.
		-	Eight external rows of Comb Plates.
		-	Bioluminescence.
		-	eg. Ctenoplana, Pleurobrachia etc.
		-	Reproduction sexual.
Phylum Platehelminthes (Flat worms) �
		-	Body dorsiventrally flattened.
		-	Endoparasite.
		-	Triploblastic, bilateral symmetry.
		-	Acoelomate
			-Flame cells- for excretion & osmoregulation.
		-	Hermaphrodite
		-	Reproduction � Sexual - Fertilisation internal.
		-	Organ level organisation.
		-	eg. Taeniasolium(Tape worm), Fasciola hepatica (liver fluke).
Phylum Aschelminthes (Round Worm) �
		-	Free living or parasitic, aquatic and terrestrial. Bilateral symmetry and Triploblastic.
		-	Pseudocoelomate. Muscular pharynx.
		-	Male smaller and thinner than female. Fertilisation internal, development direct or indirect.
		-	eg. Ascarislumbricoides, Wucherariabancroftiietc.
Phylum Annelida �
		-	Aquatic or terrestrial.
		-	Free living or parasitic.
		-	Organ system level body bilateral symmetry and Triploblastic coelomate.
		-	Nephridia for excretion.
		-	Ventral double Nerve cord.
		-	Monoecious or Dioecious.
		-	Reproduction � Sexual. eg.
		-	Earthworm(Pheretima),Nereis etc.
		-	Metameric segmentation.
Phylum Arthropoda( Jointed Legs) �
		-	Largest phylum.
		-	Bilateral symmetry, Triploblastic, segmented coelomate.
		-	Body - Head, Thorax and Abdomen(three parts).
		-	Blood without haemoglobin and circulatory system open.
		-	Respiration by gills, book lungs and trachea.
		-	Excretion by malpighian tubules.
Phylum Mollusca �
		-	Soft body animals. Second largest phylum.
		-	Aquatic, bilateral symmetry, triploblastic, coelomate. Body unsegmented divided into head, muscular foot and visceral hump.
		-	Soft mantle over visceral hump. Respiration and excretion through gills.
		-	Unisexual.
		-	Sensory tentacles on head and Radula in mouth.
		-	Oviparous.
		-	-eg.Pila, Octopus etc
PHYLUM �ECHINODERMATA
		-	Body surface spiny, (due to calcareous ossicles)
		-	Marine , organ system level, adult radially symmetrical, triploblastic coelomate.
			Mouth ventral
		1	Water vascular system present for locomotion, capture and transport of food and respiration.
		2	Sexes separate fertilization external, development indirect
		-	e.g. �Asterias (Starfish), Sea urchin (Echinus), etc.
PHYLUM HEMICHORDATA
		1	Marine
		2	Bilateral symmetry, triploblastic, coelomate
		3	Body
		i	Proboscis
		ii	Collar
		iii	Trunk����
		4	Circulatory system open
		5	Gills for respiration
		6	Proboscis gland for excretion
			Sexes separate fertilization external, development indirect, e.g. Balanoglossus.�������������������������
PHYLUM- CHORDATA
Distinguishing features
		1	Presence of Notochord
		2	Dorsal hollow nerve cord
		3	Paired pharyngeal gills slits
		4	Post anal tail present
		5	Heart is ventral
	SUB PHYLA �
		1	Urochordata or Tunicata, Notochord only in larval tail� e.g.� Ascidia
		2	Cephalochordata notochord head to tail in all stage �e.g. Branchiostoma
		3	Vertebrata:� Notochord replaced by a vertebral column.
SUB PHYLUM- VERTEBRATA
AGNATHA-without jaw
		CLASS- Cyclostomata-
		Ectoparasite on fish
		-	C ircular mouth
		-	No scales and paired fins
		-	Marine but go in fresh water for spawning and die. Larva returns to ocean.
		-	Eg. Petromyzon, Myxine.
Gnathostomata � with jaws
		Class - Chondrichthyes
		-	Aquatic and terrestrial both.
		-	Two pairs of limbs.
		-	No neck.
		-	Body has head and trunk only.
		-	No external ear, tympanum on surface.
		-	Heart three chambered.
		-	Cloaca present.
		-	Respiration by gills, skin and lungs.
		-	Sexes separate.
		-	Fertilisation external, development direc
		-	eg. Ranatigrina, Bufo, Hyla etc.
Class Reptilia �
		-	Creeping or crawling mode of locomotion.
		-	Skin with scales/scutes.
		-	Tympanum on surface.
		-	Heart three chambered (Four chambered in crocodile).
		-	Fertilisation internal, development direct.
		-	eg. Chelone, Testudo, Naja, Hemidactylus etc.
Class Aves �
		-	presence of feather, beak and forelimb in form of wing.
		-	Hind limb adapted to clasping, walking and swimming.
		-	No glands on skin (only oil gland at tail base).
		-	Hollow bones (pneumatic).
		-	Air sacs connected to lungs to supplement respiration.
		-	Crop and gizzard are additional chambers in digestive system.
		-	Warm blooded.
		-	Heart four chambered.
		-	Sexes separate.
		-	Fertilisation internal and development direct.eg.
		-	�Columba, Psittacula etc.
Class Mammalia �
		-	Aquatic, terrestrial and aerial.
		-	Mammary glands present for milk production.
		-	Two pairs of limbs.
		-	Skin with hair.
		-	Ear with pinna.
		-	Homoiothermic.
		-	Heart four chambered.
		-	Excretion by kidneys.
		-	.Sexes separate.
			Internal fertilisation, vivipary (exception Platypus).
		-	eg. Whale, Rat , Man, Tiger etc.
		-	Respiration by lungs