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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.

Protista Kingdom

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