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DORSIVENTRAL LEAF: The dorsiventral leaves are found in dicots. In the vertical section of dicot leaf there are mainly divided into three parts. They are. Epidermis Mesophyll Vascular Bundles Epidermis: The upper and lower epidermis of leaf is covered by cuticle. The Adaxial(lower) surface has more number of Stomata than upper surface.Sometimes the upper surface lacks Stomata. Mesophyll: The layer present between the upper and lower epidermis is called as mesophyll. It possess chloroplast and carry out photosynthesis. it contains parenchymatous cells. Mesophyll is two types of parenchymatous cells.     -Palisade parenchyma     -Spongy parechyma Polisade parenchyma is an elongated cell,arranged vertically and parallel to each other. present on upper side of mesophyll Spongy parenchyma are oval or round loosely arranged situated below the palisade parenchyma extending to the lower epidermis. it contains air cavities.

ISOBILATERAL LEAF (MONOCOTYLEDENOUS): General features: Isobilateral leaves are found in Monocot leaves. Stomata is equally distributed on lower(abaxial) and upper(adaxial) surface of the leaf. Cuticle covers both upper and lower surface of the leaf. Leaf  is distinguished into three parts. Theyare              -Epidermis              -Mesophyll              -Vascular bundles Epidermis has stomata and cuticle.  In monocots Mesophyll is not defferentiated into polisade and spongy parenchyma unlike in Dicots.  Vascular bundles are seen in the mid-ribs and veins of the leaf. The size of the vascular bundle is depend on the size of the veins. Parellel venation is present in monocot leaves. In grasses ,certain upper epidermal cells along the veins modify themselves into large empty colourless cells.these are called Bulliform cells. When bulliform cells absorbs water it becomes turgid and the leaf surface gets exposed. When they get

Guttation: It is the removal of excess of water in the form of water droplets is called guttation. This can be seen only in shurbs and herbs. And not in higher plants. Water droplets are found when the evaporation is low, during early morning and evening, droplets can be seen on the tip of veins and surface of leaves. Guttation is found only in Root pressure type of transportation of plants.                              Transpiration: It is the process of removal of water from the upper surface of leaves through stomatal opening in the form of water vapour is called Transporation. This is seen in higher plants and takes place when the excess of water is present. It creates tranpiration pull for absorption and transport of plants. It supplies water for photosynthesis. Also transports minerals to the various parts of the plant. It keeps the cell turgid and cools leaves surface by evaporative cooling.                                

Root pressure: Water and minerals are transported from roots to the different parts of the plants by a passive process in a small height plants like herbs and shurbs. This process of transportation is called Root pressure This is a process of 'pushing' up of water to small heights. Guttation: Water loss from the plants in a liquid phase is known as guttation. This takes place in shrubs and herbs. It takes place only in root pressure type of transportation.

Constipation: The bowel movement does not take properly and is hard to pass outside of the body. The feacus get dry and hard to pass. This happens because of dehydration, improper eating, lack of dietary fibres. This causes abdominal pain. This can removed by taking food which contains fibre. This allows easy bowel movements and this problem can be removed.

Transcription: It is the process in which the double standard DNA is transcripts into single standard mRNA. This process involves in protein synthesis.            DNA→mRNA mRNA is the small piece of DNA . This single standard mRNA forms the second strand in the opposite direction. In this mRNA Adenine binds with Uracil instead of Thymine.       In DNA                 In mRNA            A⇉T                         A⇉U      G⇛C                        G⇛C This takes place in nucleus and then reaches to cytoplasm. Translation: This takes place in cytoplasm. In this process proteins are formed by mRNA.            mRNA→Proteins mRNA binds with Ribosomes and forms the proteins. By this amino acids are formed which together called as proteins.                         

Immune system is responsible for affecting with the foreign bodies or germs and getting affected by the diseases. In childrens the immune system is lower in size and not powerful so as we grow up and reaches at the adult stage, simultaneously the immune system also grows in a large size and at adult stage  the immune system will be at its peak level preventing from all type of diseases. Then as we grew much older the immunity also decreases, when we become old, again it reduces to its  initial size as it was in the children stage that is reduced size of immune system. This is the reason that children and old peoples get affected early by the diseases as it has much reduced size immunity. Whereas in adults the immune system is at the peak level and at that stage they will not get affected easily by diseases and they are more energetic at that stage and possesing a capability of doing a much work.

Sometimes, you feel fullness in your upper abdomen or in your stomach. This happens because of over eating, eating of spicy, fatty, oily,  and heavy foods. This fullness is also due to filling up of gas because of eating heavy food items. The food did not get digest so it leads to feeling of fullness. Spicy and oily foods are mainly responsible for this. The scientific term used for this is 'Indigestion'. This does not cause any disorder in the body but it feels uncomfortable for a time and then it gets normal after taking a curd or anything which is helpful in digesting the food. Curd is the simple and easy remedy for getting rid of this problem and which feels you comfortable after having a glass of curd.

Antigens:  These are the substances which enters into the body and attacks on the immune system and causes harm to the body.  These are the foriegn substances that induce the production of antibodies. However antigens are responsible for the formation of antibodies. Antibodies are produced by the immune system. Antibodies: These are the proteins which are formed by the immune system and kills the harmful foreign substances. Antibodies get activated when any foreign substance enters into the body.  Antigens induce to produce antibodies and both antigens and antibodies fights with each other and either of them gets win. It means if antibodies succed in killing antigens then it causes no harm to the body. And if antigens kills the whole antibodies then it may cause harm to the body. Production of antibodies is depend on the efficiency of our immune system. If the immune system is powerful then more amount of antibodies are produced. Immune system is at the peak level i

         Functional groups          Formulae         1.       Alcohol                                R-OH         2.       Ketone                                 R-CO-R              3.      Aldehyde                              R-CO-H         4.      Carboxylic acid                   R-COOH         5.       Ether                                    R-O-R         6.       Ester                                     R-COO-R         7.       Amides                                 R-CO-NH₂         8.      Cyanides                               CN⁻           9.      Nitriles                                  R-CN        10.     Carboxylate ion                  R-COO⁻        11.     Thiols                                    R-SH        12.     Azide                                       N⁻³         13.     Amines                                  R-NH₂         14.     Imine                                    R₃N⁻         15.     Imide   

Plants are generally planted for the reduction of  air pollution and to provide a refreshing breath to us. But how did it happen? Actually many of us have a wrong perception that plants releases oxygen and intakes carbondioxide But in the Respiration, the process which involves uptake of oxygen and release of carbondioxide, there is no oxygen which is released in the environment and instead of that carbondioxide is releasing. So how it is helpful to us and to the environment? During the process of photosynthesis, plants utilises carbondioxide, water,sunlight as the major components and prepare its own food material. Photosynthesis takes place only during day time.  Thus plants utilises carbondioxide for photosynthesis which helps in reduction of that harmful gas from the atmosphere. But during the night time photosynthesis process is not possible as there is no light. So plants undergoes only Respiration process at night. It might be harmful to our health to be near the

Yes. Male Pigeon produces milk.     In pigeon both the sexes, male and female produces milk and feed thier young one's.     Milk is produced in Crop region. Mainly in the glandular region of crop, the milk is produced to feed the young ones.      The Prolactin harmone stimulates and controls the formation of pigeon's milk.

External features to identify Monocts: By leaves : Monocots consist of parallel venation. This is the main feature for identifying monocots. By Roots : Fibrous roots are present in monocots. By Seed : Embryo contains single cotyledon. Ex: Wheat,maize,etc. External features for identifying dicots: By leaves  : Reticulate venation on the surface of leaves. By Roots  : Tap root system is found in dicots. By seed  : Embryo  contains two cotyledons. Ex: Gram, pea, etc.

Tissues: A group of cells which are structurally and functionlly similar are called as tissue. Types of tissues: Tissues are of two types 1.Meristematic tissue. 2.Permenant tissue. Meristematic tissue: A group of cells which are immature and involves in active cell division. These are present at the apical region of root, stem and lateral branches.    Meristematic tissue is again divided into many types based on origin, position and plane.     On the basis of origin it is divided into two types. They are:         a. Primary meristem.         b. Secondary meristem.      On the basis of position it is further divided into three types. They are:         a. Apical meristem.         b. Intercalary meristem.         c. Lateral meristem.       On the basis of plane of division it is divided into three types. They are:         a. Plate meristem.         b. Rib meristem.         c. Mass meristem. Permenant tissue: A group of cells which are matur

MEIOSIS: The cells undergoes division and results in the formation of haploid daughter cells and reduces the number of chromosomal number by half. Meiosis is also called as Reduction division or Heterotypic division. Key  features of meiosis: It involves nuclear and cell division called meiosis-1 and meiosis-2 respectively. Only one cycle of DNA replication takes place. It involves paoring of homologous chromosomes and recombination between them. At last four haploid cells are formed . Meiosis-1: Meiosis-1 initiates when the parental chromosomes replicate to produce identical sister chromatids.     It has four phases. They are: 1.prophase-1 2.metaphase-1 3.anaphase-1 4.telophase-1 Prophase-1: It is sub divided into five(5) phases. 1. Leptotene : chromosomes comes closer together and visible under microscope. 2. Zygotene:  chromosomes start pairing together forming a synapse. Paired chromosomes are called homologous chromosomes. This c

Stereoisomers are further divided into two types. They are 1) Enantiomers 2)Diastereomers Enantiomers: These are the isomers which are mirror images and non-superimposable are called  Enantiomers. These are also called as optical isomers. Ex.(+)Menthol and (-)Menthol. Diastereomers: These isomers are non-mirror images and non-superimposable are called Diastereomers.    

Constitutional isomers are further divided into three types.They are: 1)Positional isomers 2)Functional group isomers 3)Chain isomers Positional isomers: The compounds having the same molecular formula but differ in the position of double bond or triple bond or the functiobla group are called positional isomers. Ex:  But-1-ene ; But-2-ene.       Pentan-1-ol ; Pentan-2-ol. Functional group isomers: The compounds having the same molecular formula but which differ in the functional groups is called functional group isomers. Ex:C₂H₆O⇒CH₃-CH₂-OH(Ethanol)  ;  CH₃-O-CH₃(Dimethyl ether). Chain isomers: The compounds having same molecular formula but differ only in arrangements of carbon atom in the main carbon chain. Ex: C₄H₁₀⇒Butane ; 2-Methyl propane.

ISOMERISM: The compounds having the the same molecular formula but which differ in their properties is called as Isomers and the phenomenon is considered as Isomerism.          It is further categorized into two types: They are 1) Constitutional isomerism. 2) Stereoisomerism. 1) Constitutional isomerism: The compounds constituting same molecular formula but differ in the arrangement of atoms or ions within a molecule is called as Constitutional isomers and the phenomenon is called Constitutional isomerism. 2)Stereoisomerism: The compounds having the same molecular formula vut which differ in spatial arrangement of atoms or groups around the carbon atom is called stereoisomers.

Electrons: Negatively charged ions are considered as electrons. Electrons are discovered by J.J.Thomson. Protons: Positively charged ions are considered as protons. It was discovered by Ernest Rutherford. Neutrons: The ions which contains No charge  are called Neutrons. It was discovered by James Chadwick.

Placenta: The organ which is formed by the combination of foetal tissue and maternal tissue for the exchange of nutrients and gases are called as placenta.     The foetal tissue is the part of foetus and maternal tissue is from uterine wall of mother. Placentation: The intimate relation between uterine wall of mother and foetal tissue which is  mainly from chorionic membrane of foetus for the exchange of nutrients, minerals, respiration and excretion is called Placentation.

Neoteny: The occurance of both adult and juveline characters together in an organism is called as Neoteny.    This is seen in Amphibians. Example is Axolotol larva of Ambylostoma.   Neoteny can also be defined as the loss of sexual maturity in the organisms and retain of larval characters along with adult characters. Why Neoteny is observed in an organisms? Neoteny occurs due to lack of thyroid stimulating harmone which stimulates thyroid to produce thyroxine. The hypothalamus of the brain fails to stimulate the thyroid gland to produce growth harmone which stops the metamorphosis. Axolotol of Ambylostoma can again get metamorphose by giving injections of Iodine or by giving shocks of Thyroxine harmone.

Prokaryotes: Prokaryotes includes bacteria, blue-green algae, mycoplasmas and PPLO. They are smaller and multiply more rapidly. They vary greatly in shape and size. All prokaryotes have a cell wall and cell membrane. No well defined nucleus. Matrix is filled with cytoplasm. In addition to genomic DNA, it has smaller DNA's called Plasmids which is resistant to antibiotics. No organelles are present except ribosomes. It has unique Inclusions. Inclusions is the reserve material stored in the cytoplasm. Differentiated form of cell membranes called mesosomes is the characteristic of prokaryotes. Eukaryotes:  Eukaryotes includes protists, plants, animals and fungi. Compare to prokaryotes, they multiply slowly. The cells are not identical. All eukaryotes do not have cell walls. Well defined nucleus with a nuclear envelope. Cytoplasm have many compartments due to presence of cell organelles. Genetic material is organised into chromosome. Many membrane bound cell

Syrinx Syrinx is a 'vocal organ' which is found only in birds.  It produces sound in birds. It is situated between trachea and bronchi of a bird. Supported by last few(three) tracheal rings and first two brnnchial rings.      Syrinx consist of expanded chamber called "Tympanum" which is also supported by last three or four tracheal rings and first two rings of bronchi.        The voice is produced by the vibration of tympaniform membrane when the air expelled out from the lungs. Mucous membrane of each bronchus forms an internal tynpaniform membrane and External tympaniform membrane. These membranes are regulated by "Intrinsic syringial muscles" and apair of "Sterno-tracheal muscles".   At the junction of two bronchi a bony ridge,the "Persulus" extends dorso-ventrally.

Fruit is a characteristic feature of flowering plant. A friut is a ripened or mature ovary which is developed after fertilisation.    If a fruit is developed before fertilisation then such fruits are considered as Parthenocarpic fruits.     Banana is one such example of parthenocarpic fruit.   Generally ovary develops into fruit and ovules develop into seeds. But in banana seeds are absent and fruit is developed before ovary gets fertilised.