Biology Blogs For Class 11th, 12th & NEET

                                    Structure Of Neuron All animals have a very important functional neural system in their body which is comprised of highly specialized cells called Neurons which can detect, receive and transmit different kinds of stimuli. Every neuron is made up of a cell body and cell process (Dendron and axon ).                                                    Cell Body or Cyton -   It contains uninucleated cytoplasm. Except for centriole, all cell organelles are found in the cytoplasm . The centriole is absent in the nerve cell thus cell division is absent . Nissl's granules - Endoplasmic Reticulum and ribosomes form granules like structures called Nissl's Granules. Cell Process -   Dendron - The fine bra...

                                       Phylum - Chordata               Class Amphibia  As the name indicates (Gr., Amphi : dual, bios, life), amphibians can live in aquatic as well as terrestrial habitats. Most of them have two pairs of limbs. Body is divisible into head and trunk. Tail may be present in some. The amphibian skin is moist (without scales). The eyes have eyelids.  A tympanum represents the ear. Alimentary canal, urinary and reproductive tracts open into a common chamber called cloaca hich opens to the exterior. Respiration is by gills, lungs and through skin. The heart is threechambered (two auricles and one ventricle). These are cold-blooded animals. Sexes are separate. Fertilisation is external. They are oviparous and development is indirect. Earliest amphibians - Ichthyostega basically a fish wi...

                                       Phylum Chordata dorsal, hollow nerve cord – becomes the brain   spinal cord notochord   - flexible, fibrous rod along the back (replaced by vertebrae in advanced vertebrates) pharyngeal gill slits - openings in the throat region. postanal tail – most other animals with tails near the anus have anus at end of the tail. T hese features may each be lost or altered in the adult. This phylum has three subphyla: 1. Cephalochordata, 2. Urochordata, and 3. Vertebrata 1. Subphylum Cephalochordata (clade) – lancelets fishlike creatures that bury selves in mud and filter feed all four key chordate feature present in adults like vertebrates, muscles broken up into bands called myomeres (body segmentation) essentially no brain in adults Ex.- Urochordata – Ascidia, Salpa, 2. Subphylum Urochordata...

                          Phylum Mollusca (clade) – mollusks  very successful phylum: over 93,000 named, living species The largest number of living species for animals after Arthropoda  mostly aquatic, but over 35,000 terrestrial species (more than all terrestrial vertebrates)  includes snails, slugs, clams, oysters, chitons, cuttlefish, octopi, etc.  from microscopic to 21 m (giant squid – largest invertebrate)  economically important (food, ornamentation, currency, pests)  Defining Characteristics Of Mollusks:   Bilateral symmetry with true coelom ; usually have a differentiated head unsegmented (some argument as to whether lost during evolution or never present in phylum)   Three main body parts : muscular foot, visceral mass, and mantle muscular foot – used for locomotion, food capture, attachment  · may be solid or have tentacles or maybe a “wing” ...

                                     Amino Acid Amino acids are organic compounds containing amine (-NH2) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid. Amino Acids Structure Amino acids have the general form H2NCHRCOOH. (or)   General properties of Amino Acids ·          Amino acids are soluble in water and insoluble in hydrocarbon solutions. ·          They are crystalline solid substances. ·          They have very high melting point compared to their boiling point. List of Amino Acids There are around twenty amino acids, which are involved in the construction of proteins. The lists of twenty amino acids are: Alanine, aspartic acid, asparagines, arg...

                     Gram-Positive Bacteria & Gram-Negative   Bacteria have a cell wall made up of polysaccharides known as Peptidoglycans which gave them strength and rigidity and this is important since bacteria observe some osmotic pressure due to the variation of different solutions they encounter and their cell wall which prevents the cell from shrinking or swelling. So , on the basis of the cell wall and the pattern of gram staining, bacteria are classified into two categories - Gram-Positive and Gram-Negative. Gram-positive bacteria  have double-thick walls which consist of around 30 layers of peptidoglycan and surrounds a single plasma membrane.  They do not have an outer cell membrane but have a complex cell wall made up of teichoic acid.  For example - Staphylococci.   Gram-negative bacteria  have a much thinner cell wall consisting of peptidoglycans having high lipid content...

                                     Jacob Syndrome  Jacob syndrome is due to presence of extra Y chromosome in males . This syndrome is also known as super male or criminal syndrome . Usually  in human being , there are 46 chromosomes but such a patients have extra Y chromosomes due to this the chromosome number changed from 46 to 47 . For more information click on this video .  Visit the full video for Jacob or supermale syndrome .    

                                          Brown Algae  Classification : - Kingdom -  Chromista                           Phylum -  Ochrophyta Class -         Phaeophyceae  Scientific Name - Phaeophyceae  Commonly Called - Sargassum  Weed Number Of Species -  1500 and mostly they are Marine. Colour - The color may vary from brown to olive green. This is due to the presence of pigment Fucoxanthin and chlorophyll ( a, c ). Characteristics - They are multicellular. They are capable to reproduce through vegetative reproduction (fragmentation ), asexual ( zoospore ), and sexual ( from isogamy to oogamy ). Laminarin and mannitol are present in it as a food material. They follow diplo-haplontic as well as a diplontic life cycle. Kelp ...

    Vitamins are those organic compounds that are recommended in a very short amount in diet however their deficiency turns into a  specific disease.  The term “Vitamine” was coined from the word vital + amine since the earlier identified compounds had amino groups. Later work showed that most of them did not contain amino groups, so the letter ‘e’ was dropped and the term vitamin is used these days.  They are generally present in our food which we have taken for nutrition. · Maximum vitamins cannot be synthesized in our body on the other hand plants can synthesize almost all of them, so they are considered to be an essential food factor. · In our body, some of the vitamins which we are needed are secreted by the bacteria of the gut. ·  Different vitamins belong to various chemical classes. · A  small amount of vitamins used to perform specific biological functions in our body like the growth and health of the organ...

                                         Carbohydrate         Carbohydrate is one of the main biomolecules present in our body in the form of sugar ( glucose ), starch & fiber.  Besides providing energy to all over the body, carbohydrates play a significant role in many cellular activities. Carbohydrates are simply the combination of carbon, hydrogen, oxygen. They are also known as " the derivatives of aldehyde and ketone ." The general formula of carbohydrates is CN(H 2 O)N . In biochemistry the word carbohydrate is known by another name - Saccharide means sugar molecules. On the basis of the composition of sugar, molecules carbohydrate is divided into the following parts - 1. Monosaccharides - Here the word Mono means single& saccharide means sugar molecules & hence the term Monosaccharides. Monosaccharides are the molecu...

                                      Western Blotting Western blotting is a type of blotting which is used for identifying particular protein from a sample by using an antibody specific to that protein. This technique was developed by Towbin and his co-worker in 1979. This technique is also known by another name Immunoblot . In this method nitrocellulose and nylon, the membrane is used for blotting. Sometime Polyvinylidene fluoride is also used for blotting purposes. The probe used is an antibody to detect a specific protein. The positive signal indicates that the protein of interest is present in the given sample. The antibody is labeled with radioactive material so that it produces light after combining it with the enzymes. Detection -  Western blotting can be detected in two ways - Direct Detection -  Primary antibody which is made up of purifying the desired pro...

                                           Water Cycle  Water is  really a very  powerful factor of all ecosystem . All organisms need water for their survival and growth . Water has three phases - solid , liquid and gas . The liquid phase is important for living a life on planet and gaseous phase is important for the respiration process . Water cycle is also known by its another name"  Hydrological Cycle " . Water Cycle -   Water cycle is generally the journey of water from one place to another and from one state to another state . Their is  no end and it is a   continuous process that is why it is called "Cycle" .  Let us understand the water cycle The sun heats the surface of earth as a result the water starts evaporating in the form of water vapor . The water vapor condense and change into liquid and  form clouds ...