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Sunday, August 16, 2020

Protista Kingdom

  • Eukaryotic
  • Unicellular
  • Aquatic
  • Eg: Amoeba, Plasmodium, Euglina, Paramecium
  • Nutrition:
    • Autotrophic => Euglina & Paramecium
    • Heterotrophic => Amoeba & Plasmodium


Euglina:

  • Euglina exibits characteristics of both plants & animals. 
  • Euglina is the "connecting link" between plants & animals.
  • Euglina is also called as Green Protisa


Plasmodium:

  • Plasmodium is the pathogen of maleria
  • Vector for this pathogen is Female anafeliz mosquito.


Paramecium: 

  • Paramecium is also called as Slipper animal.





Thursday, July 30, 2020

Virus

  • Virus was discovered by => Dimitri Ivanovsky (In 1892).
  • Dimitri Ivanovsky discover virus during investigation of plant disease called Tobacco mosaic.
  • Study of Virus is called as Virology.
  • First discovered virus => Tobacco mosaic virus.

Characteristics of Virus:

  1. Complete lack of cellular level composition like Cytoplasm, Cell membrane, Cell organelles etc.
  2. Inside plant viruses transmit through phloem and Inside animal viruses transmit through blood.
  3. Viruses have either DNA or RNA but both never.
  4. viruses is composed of neucleoproteins.
  5. Viruses is assumed as accessories of living and non-living organisms. Thus viruses exhibit the properties of both living & non-living.

 Sr. No.

 Living properties of Virus

 Non-Living properties of Virus

 1  The presence of DNA or RNA.  Absence of cell.
 2  Structural diversity.  Lack of protoplasm.
 3  Geneticity & Parasitic properties.  Non re-productivity & growth outside 
 4  Sensitivity and Evolution.  Stored in the form of crystal outside 
 5  To spread diseases.  Lack of metabolic activities like 




Structure of Virus:

 
      There are three main constituents(Components) in the structure of virus.
  1. Protein caspid.
  2. Nucleic acid (DNA or RNA).
  3. Thick outer layer.
  • In plant virus nucleic acid RNA is present.
  • In animal virus nucleic acid DNA is present.


Types of Virus:




1) Plant Virus:

  • This is a nucleic acid of RNA.
  • The virus yellow mosaic virus (YMV) is a plant virus.

2) Animal Virus:

  • This is a nucleic acid of DNA or RNA & usually spherical in shape.
  • The virus like influenza, mups etc. are animal virus.

3) Bacteriophase:

  • Such virus only depend on bacteria.
  • In this virus DNA are present only & can destroy other viruses.
  • It is also called as T2 Phase virus.


Advantages of Viruses:

  • Used in study of Biotechnology.
  • Bacteriophase virus used as a water preservative & due to its presence water doesn't rotten & remains fresh. 
  • Viruses are useful in cleaning the blue green algae. 





Thursday, July 23, 2020

Monera Kingdom, Bacteria

Monera Kingdom:

  • Unicellular.
  • Prokaryotic.
  • Contain 70S Ribosome.
  • DNA is not bounded by nuclear membrane.
  • Lack of organelles mitochondria, lysosomes, plastids, Golgi bodies, endoplasmic reticulum, centrosome, etc.
  • Eg:- Bacteria, Blue green algae (Cynobacteria).


    Bacteria: 

  • Invented by => Antony van Leeuwenhock (In1683).
  • Father of bacteriology => Antony van Leeuwenhock.
  • Name bacteria was given by => Aranberge (In 1829).
  • This is a prokaryotic cell & kept under Monera kingdom.
  • In 1881 Robert Coach detected & separated bacteria of anthrax & tuberculosis.
  • Chlorophyll & Mitochondria are absent & respiratory activities done by misosomes.
  • Cell wall is made up of Phospholipid.

Sunday, July 19, 2020

Cell Division


  • Firstly observed by Flemming (in 1882).
  • Hence Flemming is known as Father of Cell division.
  • According to theory of cell division old cells splits into new cells & formation of new cell is called Cell division.
  • This process is also called as Cell production.


Stages of Cell division, Mitosis

  • Types of cell division:
    • Amitosis
    • Mitosis
    • Meiosis

Friday, July 17, 2020

Cell Cycle


  • In cell division old cells are split and new cells are form and the repetition of this process is called as cell cycle.
  • Cell cycle has four stages:
    • Gap1 Phase (G1)
    • Synthesis Phase (S)
    • Gap2 Phase (G2)
    • Mitosis Phase (M)
  • G1, S and G2 phase are collectively known as Inter phase.


Cell Cycle


  1. Gap1 Phase (G1):
    • Cell is prepare for cell division.
    • At restriction point cell is committed to division and moves into S phase.

Thursday, July 16, 2020

Genetics


  • Genetics word first used by => W. Watson (in 1905).
  • Transmission of character from one generation to next generation is called Heredity.
  • The process of transfer of hereditary character from generation to generation called as Genetics.
  • The characteristics which transmit from generation to generation is transported by Gene.



 Gene:

  • Gene word first coined by => W. Johannsen (in 1909).
  • It is a unit of hereditary material located on chromosome.
  • Gene itself or with other gene determine character of organism.
  • Gene exist in number of alternative forms termed as alleles.
  • Gene occasionally undergo for radial changes called as Mutation.
  • The modern concept of perception about the gene was given by => Benjer (in 1956).
  • Functional unit of gene => Cistron
  • Unit of gene responsible for mutation => Muton
  • Unit of gene take a part in recombination => Recon
  • In Human 35000 gene are present.

  • Gregor Johann Mendel said that hereditary character is transfer by gene.
  • Hence Gregor Johann Mendel is known as Father of Genetics.


Mendel's Experiment:

  • Mendel chooses 7 pair of pea plant species for his experiment.

 

Characters

 Dominant characters

 Recessive characters 

 Shape of the seed.  Spherical smooth seed.  Wrinkled seed.
 Color of the cotyledon.  Yellow  Green
 Color of flower.  Red  White
 Shape of the fruit.  Smooth  Shrinked
 Color of the fruit.  Green  Yellow
 Position of the flower.  Tall  Farthest
 Length or Height of the plant.  Tall  Dwarf



Mono-hybrid Cross:


Mendel made cross between 2 pure plant having contracting character for single trait called Mono-hybrid cross (i.e. Tall & Dwarf plant for height)
 

Mono hybrid Cross

Phenotype ratio => 3 : 1
Genotype ratio => 1 : 2 : 1


Di-hybrid Cross:

Mendel made cross between 2 pure plant having in 2 pair of contracting character i.e. color & shape of seed called Di-hybrid cross. (i.e. Plant having round seed with yellow color & wrinkle seed with green color.)

 
Di hybrid Cross


Phenotype ratio => 9 : 3 : 3 : 1
Genotype ratio => 1 : 2 : 1 : 2 : 4 : 2 : 1 : 2 : 1
 


Mendel's Law of Heredity:

  • On the basis of mono-hybrid and Di-hybrid cross Mendel proposed law of heredity.

1. Mendel's First Law: (Law of dominance)

    • According to it when two dissimilar unit factors are present in an individual only one is able to express.
    • One that express itself is dominant character while which fail to express is recessive character.
    • In the first generation only the dominant character is visible, while the recessive character is hidden and it appears in the next generation.
 

2. Mendel's Second Law: (Law of segregation)

    •  According to this law during the gametes formation both the character which governed by gene is segregated and out of these factors only one factor is reached in the gamete.
    • Both factors never come at a time in the gamete.
    • This law is also called the Law of purity of Gametes.

3. Mendel's Third Law: (Law of Independent Assortment)

    •  According to this law various pairs of the factors which exist in organism are independent to each other.
    • Thus organism of new appearance may born.
 

Terms Related to Genetics:

  1. Phenotype:
    • The characteristics of the organism which are directly & visibly appreciable is called Phenotype.

Tuesday, July 14, 2020

Chromosome, DNA, RNA

Chromosome:

  • Chromosome name was given by => Waldeyer (in 1888)
  • Chromosome is thread like structure found in nucleus.
  • Chromosomes are basic constituents of genetic substance Chromatin.
  • During Cell division Chromatin breaks into pieces and form Chromosome.
  • Each Chromosome is made up of two Chromatids, which joint together at a point called centromere.
  • On Chromosome various genes are located.
  • Gene is the functional unit of DNA, made by segment of DNA.
  • Characteristics which transmit from generation to generation is transported by Genes and these genes are carried out by Chromosome.
  • Thus Chromosome are called as Vehicle of Heredity.

Number of Chromosome in different organism:


Organism

 Number

 Pair

 Pigeon  40  80
 Chimpanzee   24  48
 Cat  19  38 
 Onion  8  16     
 Dog  39  78
 Human  23  46
 Frog  13  26
 Pea  7  14
 Horse  32  64
 Wheat  21  42
 Tomato  12  24
 Ascaris  1  2
 Housefly  6  12
 Mosquito  3  6
 Monkey  21  42
 Tobacco  24  48


  • One set of Chromosome (Haploid) is called Genome.
  • Two sets of Chromosome (Diploid) found in somatic cells.

DNA: (Deoxyribo Nucleic Acid)

  • First who isolated DNA from nucleus of pus cells => Friedrich Miescher (in 1869).
  • DNA is Polynucleotids.
  • Almost all amount of DNA is present in nucleus of cell but very small amount also present in Mitochondria and Green Plastids.
  • In 1953 Watson and Crick gives double helix model of DNA, each helix has a diameter of nearly 20Å.
  • DNA is macro molecule in which large number of nucleotides are present.
  • These nucleotides has three components.
    • Nitrogen base
    • Sugar
    • Phosphate group.




  • Nitrogen  base of double helix form a pair with the help of hydrogen bonds.
  • Adenine pairs with Thymine (A = T).
  • Guanine pairs with Cytosine (G = C).
  • Adenine and Thymine are complementary to each other. 
  • Guanine and Cytosine are complementary to each other.
  • Hydrogen bond between nitrogen base holds two strands together.
Function of DNA:
  • It contain genetic information in coded form.
  • DNA synthesis RNA.

RNA: (Ribo Nucleic Acid)

  • It is a single standard nucleic acid but in some virus it has double standard structure like in Retrovirus.
  • Main function of RNA is to assist Protein synthesis but in some plant and virus it acts like carrier of genetic substance.
  • Thus in viruses genetic substances are either DNA or RNA but not both.
  • RNA is made up of Phosphate, Ribose sugar and Nitrogen base.
  • RNA is found in nucleus as well as cytoplasm.




RNA is of three types:
  1. Messenger RNA (mRNA):
    • It carries the information of protein synthesis from DNA of the nucleus to Ribosome in coded form.
    • It is 3-5% of all RNA.
    • It also help in selecting amino acids.

Sunday, July 12, 2020

Difference between Plant cell and Animal cell

 Sr. No.

 Plant Cell

 Animal Cell

 1  Plant cells are larger in size.  Animal cells are generally smaller in size.
 2  Cell wall is present and made up of cellulose and chitin.  Cell wall is absent.
 3  Plastid is present.  Plastid is absent.
 4  Centrosome is absent.  Centrosome is absent.       
 5  Vacuoles are larger in size.  Vacuoles are smaller in size.
 6  Chlorophyll is present except fungi & bacteria.  Chlorophyll is absent.




Thursday, July 9, 2020

Types of Cell

 Sr. No.

 Prokaryotic Cell

 Eukaryotic Cell

 1 Nucleus is absent. Nucleus is present.
 2 Cell is small in size.
 (1-10 micron)
 Cell is large in size.
 (5-100 micron)
 3 Only one chromosome is present.  More than one chromosome is present.
 4 Cell organelles, nucleolus are absent. Cell organelles, nucleolus are  present.
 5 Cell division takes place by
 Fission or Budding.
 Cell division takes place by
 Mitosis & Meiosis.
 6 Cell wall is usually present; 
 (Chemically complex)
 Cell wall only present in plant & fungi;
 (Chemically simpler)
 7 Example: Bacteria, Blue green algae etc. Example: Fungi, Plant, Animals etc.




Sunday, July 5, 2020

Cell

  • Study of Cell is called as Cytology
  • "Cell is known as basic structural and functional unit of all Organisms or Living beings (Life) "
  • human body exists nearly 10 /\ 14 (10 to power 14) Cells.
  • Cell was Invented by => Robert Hook (in 1665) {He was discovered dead cell in Bark of Cork}
  • Cell has been made from a life saving substance called as Protoplasm {Protoplasm is the physical base of the life and in Protoplasm nearly 80% water is found}
  • Protoplasm was discovered by => J. E. Purkinje (in 1939)
  • Protoplasm is also of two types- 
    • Nucleoplasm - (Present inside the nucleus)
    • Cytoplasm - (Present between nucleus and cell membrane)
==========================================

Cell Theory:

  • Cell theory was given by Schelder and Schwann (in 1838-39)
  • Important points regarding cell theory:
    1. Every organisms originates from a cell.
    2. Each cell arises from preexisting cell.
    3. Cell is self independent unit, it takes part in metabolic activities.
    4. Core of the cell is nucleus


Some Important Points
* Smallest Cell => Mycoplasma gallisepticum
* Largest  Cell => Egg of Ostrich (Weight - 1250 gm)
* Longest Cell => Nerve Cell (Length up to 1 m)\
* Biggest single cell organism => Acetabularia




Cell Structure and it's Functions

Cell have various type of structures like cylindrical, elliptical, spherical, transverse etc.

Cell Components:


1) Cell membrane:

  • It is also called as Plasma membrane.
  • It is the outermost layer of the cell.
  • It is semipermeable membrane.
  • In plant cell it is found within cell wall.
  • It is made up of phospholipid molecules.
Function:
  • Control the molecular activities between cell and it's other medium which interacts with cell. 


2) Cell Wall:

  • Only present in Plant cell.
  • it is made up of non living substance
  • Cell wall of algae and plants are made up of Cellulose.
  • Cell wall of fungi and bacteria are made up of Carbohydrates.
  • Cell Wall of fungi is made up of => Chitin
  •  Cell wall of bacteria is made up of => Peptidoglycan
Function:
  • It protect nucleoplasm and cell membrane from external attack.


3) Protoplasm:

  • Name was given by Purkinje (in 1839).
  • Whole fluid present inside plasma membrane is Protoplasm.
  • It is made up of water, ions, salt and organic molecules
  • It is a living part of cell.
  • It is divided into two parts
    • Cytoplasm: Present between nuclear membrane and cell membrane.
    • Nucleoplasm: Present inside nuclear membrane.

4) Mitochondria:

  • It was discovered by => Altman and Benda (in 1886).
  • Altman called it Bioplast and Benda called it Mitochondria.
  • It's shape is cylindrical having Diameter (0.2 -1  micrometer) and Length (1 - 1.4 micrometer).
  • It surrounded by double membrane(outer and inner membrane).
  • Outer membrane is oily and smooth.
  • Inner membrane has many folds called cristae (in plant cell it is called tubuli) and inner compartment where fluid is present called matrix.
  • Function: 
  • It is a site of aerobic respiration and they produce cellular energy in the form of ATP (Adenosine Tri Phosphate).
  • Hence Mitochondria is called as Power house of cell 


5) Golgi Bodies: 

  • It was discovered by => Camillo Golgi (in 1898).
  • It is also called as Golgi apparatus.
  • It is made up of group of tubes and vesicles.
  • In plant it is more in number and here it is known as Dictyosomes.
Function:
  • It work as storage, processing and packaging of material and packages are brought to their destination, hence Golgi apparatus is called as traffic controller of cellular molecules
  •  It is also involved in synthesis of cell wall, plasma membrane and lysosome.
  • It help in the synthesis of carbohydrate from simple sugar which combine with Protein made by Ribosome forming Glycoprotein

 
6) Endoplasmic Reticulum:

  • It was invented by => Porter (in 1945).
  • It membranous network of tubules like structure found in cytoplasm is called Endoplasmic Reticulum.
  • It is of two types:
    • Rough walled ER: At it ribosome is to be found and it is help in protein synthesis.
    • Smooth walled ER: At it ribosome is absent and it is responsible for lipid secretion. In animal cell lipid like steroidal hormones are synthesized by smooth walled ER.

7) Ribosome:

  • It was discovered by => G. E. Palade (in 1955).
  • It was firstly seen by Calede (in 1941) and called microsome, later it is called ribosome by Palade.
  • Diameter of it varies from 150 Å to 250 Å.
  • Chemically it is composed of RNA and Protein.
  • Eukaryotic ribosomes are 80S  while Prokaryotic ribosomes are 70S. (Here S=> Svedberg Coefficient)
Function:
  • It's main function to synthesize the protein, hence Ribosome is called as Factory of Protein


8) Lysosome: 

  • It was discovered by => De Duve.
  • It contain hydrolytic enzyme, which is able to digest every organic substance.
  • It help in intracellular digestion that's why Lysosome is called Digestive Vesicle.
  • Lysosome is not found in RBC of mammal.
Function:
  • It destroy every foreign substance like bacteria etc. inside the cell.
  • It replaces old and weak cell organelles, so that new cell organelles originates inside cell.
  • If there is need it destroy entire damaged or dead cell, also it destroy itself, hence Lysosome is called as suicide bag of cell.

9) Centrosome:

  • It was discovered by => Boveri (in 1888).
  • It is only found in animal cell.
  • It is not bounded by membrane, it consist of two Centriole.
  • Sometimes it is called as diplosome.
Function:
  • It help in the cell division and it form spindle fiber between pole during cell division.  

10) Plastid:

  •  It is only found in plant cell.
  • It's shape is like mitochondria, it has two membrane.
  • It is of three types a) Chloroplast b) Chromoplast c) Leucoplast.
a) Chloroplast:
  • Found in green colored plant.
  • Made up from green colored substance called as Chlorophyll (In Chlorophyll Mg metal is present).
  •  By the help of chlorophyll Photosynthesis is done in the presence of sunlight by the plant and trees, thus Chlorophyll is called as Kitchen of the cell.
  • Chloroplast is bounded by two membrane having grana and stroma.
  •  Grana => It contain chlorophyll molecule and it is a site of light reaction.
  •  Stroma => It contain photosynthetic enzyme and it is a site of dark reaction.
  • Chloroplast also contain pigments like genthophyll and carotene.
  •  The leaf of plant becomes yellow because of formation of carotene.
  • Chloroplast also contain double standered  circular DNA molecule and ribosome.
  • ribosome in chloroplast is smaller (70S) than cytoplasmic ribosome (80S).
 b) Chromoplast:
  • It is colored plastid usually red, yellow or orange color.
  • It is found in colored part of plant like flower, fruit, seeds etc.
  • Chloroplast are of different kind
    1.  Lycopene: In tomato it provide red color.
    2. Carotene: Provide yellow or orange color in plant eg:- Carrot
    3. Betanin: Found in sugar beet root.
 c) Leucoplast:
  • It is colorless plastid.
  • It store food in the form of starch, fat and protein.
  • It is found in roots and underground stems.
  • Amyloplast store starch.
  • Elaioplast store oil & fats.
  • Aleuroplast store protein.
 

11) Vacuole:

  • It is surrounded by semipermeable membrane called as Tonoplast.
  • It contains water, sap, excretory product and other material not useful for the cell, means it contain dead organelles of cell.
  • In plant it is longer in size & in animal it is smaller in size.
Function:
  • It help in osmoregulation & it store toxic metabolic waste.

12) Nucleus:

  • It was invented by => Robert Brown (in 1831).
  • It is spherical or elliptical.
  • It is centrally located major structure found in cell, in plant cell it is shifted towards periphery.
  • It control all activity of cell, hence it is called Control Room of cell.
  • Components of nucleus:
a) Nuclear membrane:
  • It is a double layered membrane.
  • It is connected with ER.
  • It is made up of protein & fat.
  • It has small holes through which cytoplasm & nucleoplasm exchange in cell.
b) Nucleoplasm:
  • It is made up from protein, phosphorous & nucleic acid.
  • Within nucleoplasm nucleolus and chromatin material is found.
 c) Nucleolus:
  • Nucleolus is rich in protein & RNA.
  • It synthesize r-RNA & transport it to other place.
  • It collect ribosome inside it. 
 d) Chromatin:
  • Chromatin is thin thread like structure forming network.
  • It is made up of histone protein, DNA & RNA.
  • DNA is main component of chromatin which causes genetic character in organism.
  • During cell division chromatin breaks into pieces & form Chromosome


 
 

Saturday, July 4, 2020

Binary Nomenclature of Organism


It became in practice in 1753.
Scientific name has two word-
  • First word - Generic name
  • Second word - Species name

 Organisms

 Scientific Name

 Man
 Homo sapiens
 Frog Rana tigrina
 Cat Felis domestica
 Dog Canis Familaris
 Cow Bos indicus
 Housefly Musca domestica
 Mango Mangifera indica
 Rice Oryza sativa
 Wheat Triticum aestivum
 Pea Pisum sativum
 Gram Cicer artictinum
 Mustard Brassica Campestris


Protista Kingdom

Eukaryotic Unicellular Aquatic Eg: Amoeba, Plasmodium, Euglina, Paramecium Nutrition: Autotrophic => Euglina ...