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Monday, 26 March 2018

The Role of Population ecology in Ecosystem

Population ecology
IntroductionBasic Population characters.
1.Population density
2. Natality3. Mortality4. Population Size

Growth and growth curves with definition,

Population dynamicsDefinition,
Intrinsic rate of increaseCommon mathematical models
Exponential population growth


Population regulationsDefinition and their Details.

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Limiting Factor in Ecosystem


Limiting Factor in Ecosystem
Types of limiting factors
i) The density dependent limiting factor.
(ii) The density independent limiting factor.

Some other Effects of limiting factor in ecosystem such as.
  1. Climatic and Atmospheric Factors
  2. Soils
  3. Water
  4. Humidity


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What is amino acids and their classification


Amino acid
Amino Acid Definition,

Classifications of Amino AcidsTwo types of amino acids
Standard amino acids
Non-Standard amino acids
Types of standard amino acids
There are three major types of amino acids:
 (1) Nonpolar R groups,
 (2) Unchargedpolar R groups, and 
(3) Charged polar R group.
Acid/Base properties of amino acids,
Titration curve of glycine
Non-standard amino acids.

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Polymerase chain reaction (PCR)


Polymerase chain reaction (PCR)


Defination of polymerase chain reaction,
The Step of PCR,
There are Three Steps of PCR.
1. Denaturation
2. Annealing
3. Extension

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PHYSIO -CHEMICAL NATURE OF CYTOPSASM


PHYSIO -CHEMICAL NATURE OF CYTOPSASM.

Components of cytoplasm.
1. Cytomembrane system
2. Cytoskeleton
3. Granular structures
4.CytosolPhysical properties of cytoplasm,
Functions of Cytoplasm.

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Morphology and structure of chromosome



MORPHOLOGY OF CHROMOSOMES
Constitute of chromosome,
  1. Telomere,
  2. Chromatids,
  3. Centromare,
  4. Primary and secondary constriction,
Types of chromosome,
Ultrastructure of chromosome.
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Saturday, 24 March 2018

Biology study: Lipids their Structures, Characteristics and their...

Biology study: Lipids their Structures, Characteristics and their...:
Lipids You are learn in Lipids Fatty acids, their types and major characteristics Types of Fatty acid 1. Unsaturated fatty acid 2. S...

Lipids their Structures, Characteristics and their Functions|Biochemistry|




Lipids
You are learn in Lipids
Fatty acids, their types and major characteristicsTypes of Fatty acid
1. Unsaturated fatty acid
2. Saturated fatty acid
Storage Lipids
Acylglycerols and thier structure
Waxes
Structural Lipids in membranes
There are Following membrane in lipids are describes.
1.Glycerophospholipids, that are the hydrophobic regions which
consist of two fatty acids joined to glycerol; 
2.Sphingolipids, that consist of single fatty acid that joined to a fatty amine, sphingosine; and sterols, compounds rigid system of four fused hydrocarbon rings.
Sterols and their Structure
Cholesterol and their structure
Glycolipids and their structure
Major functions of lipids


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Friday, 23 March 2018

Organelles of Plant cell And Their Structure and Function



Organelles of Plant cell And Their Structure and Function

1.Dictyosome (GOLGI APPARATUS)
Formation of secretions in Dictoysomes and their functions

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2.ENDOPLASMIC RETICULUM
Types of Endoplasmic Reticulum with and 
Structure Functions
(a) Smooth ER (b) Rough ER

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3.Microbodies
Glyoxysomes and Peroxisomes
Structure and Function of Microbodies

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4.Mitochondria
Structure and functon of Mitochondria

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5.Plastid
Types of plastid
Function of plastid

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6.Ribosome
Chemical composition of ribosome
Structure of Ribosome
Types of Ribosome
Function of Ribosome

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7.Vacoule 
Structure of vacoule
Function of Vacoule

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Friday, 16 March 2018

MENDELIAN INHERITANCE and Their Two laws Heredity including Further Explanation





MENDELIAN INHERITANCE and their two laws Heredity including Further explanation
Law of segregation
Law of independent assortment.
Types of crosses
Monohybrid cross
Dihybrid crosses
Patterns of Inheritance

Law of Independent Assortment defination and explantion
LAW OF SEGREGATION defination and explation
BACK CROSS and Test Cross
Complete Dominance with definition and explation
Incomplete Dominance and Mechanisms of Incomplete Dominance
Incomplete Dominance and Codominance



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Saturday, 10 March 2018

Gene Mutation and their Types



Gene mutation definition
Types of gene Mutation
Point Mutation and their Types
Frame Shift Mutation
Causes of Gene Mutation


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Friday, 9 March 2018

The history of life or The origin of life on Earth Science







The origin of life

Most research on the origin of life is not on fossils, but consists of laboratory research
on the kinds of chemical reactions that may also have taken place on Earth 4 billion
years ago. Many of the molecular building blocks of life (such as amino acids, sugars,
and nucleotides) can be synthesized from a solution of simpler molecules, of the sort
that probably existed in the prebiotic seas, if an electric discharge or ultraviolet radiation is passed through it. Once the molecular building blocks exist, the next crucial step
is the origin of a simple replicating molecule.
Although we do not know what the earliest ancestral replicating molecule was, several lines of evidence suggest that RNA preceded DNA. For instance, single-stranded
RNA is simpler than DNA, which is always double-stranded. DNA needs enzymes to
“unzip” the two strands in order to read or replicate the nucleotide information.
                           
DNA always takes on the structure of a double helix. RNA, by contrast, can interact directly
with its environment. It can be read or replicated directly. Also, RNA can take on many
different structures, depending on its nucleotide sequence. In some of those structural
forms, RNA will act as an enzyme (or “ribozyme”), catalyzing biochemical reactions.
RNA molecules are known that act as RNA polymerases, catalyzing the replication of
RNA. However, no one has yet discovered an autocatalytic RNA that could catalyze
its own replication. Such a self-replicating molecule would be one of the simplest
imaginable living systems. Some other small lines of evidence also suggest that RNA
preceded DNA, such as “prebiotic soup” experiments that have more readily yielded
the nucleotide U than T.
The (hypothetical) early stage of life, when it used RNA as the hereditary molecule,
is called the “RNA world.” Life came to use DNA later in history. One reason for the
transition from RNA to DNA may have been that RNA-based life was limited by the
relatively high mutation rate of RNA. (This reasoning is similar to the argument in
Section 12.2.1, p. 320, about the evolution of sex.) Asexual life forms cannot exist with a
total deleterious mutation rate of more than about one.
Modern RNA viruses such as HIV have a mutation rate of about 104 per nucleotide.
This limits their coding capacity to about 104 nucleotides, or about 10 genes. More
complex life forms could not evolve until the mutation rate reduced. The evolution of
DNA would have reduced, or led to a reduction of, the mutation rate.
The fossil record tells us little about the origin of life, because those events were on a
molecular scale. However, the record does tell us something about timing, and leads us
to the next stage. The Earth itself is about 4.5 billion years old. For the first few hundred
million years, Earth was bombarded by huge asteroids that vaporized any oceans.
Temperatures were too high to allow life. Life probably could not have originated
before about 4 billion years ago.
The oldest known rocks are at a site at Isua, Greenland, and are 3.8 billion years old.
These rocks contain chemical traces that may or may not be chemical fossils of life
forms (van Zuilen et al. 2002).
 Chemical evidence of this kind is inevitably uncertain, because it could have been produced by a non-biological process. Some biologists and geologists tentatively accept it as evidence of life, but few place strong trust in it. The rocks have undergone too much metamorphosis to have any chance of retaining fossil cells a if cells existed at that time. Fossil evidence of cells comes from various sites in the period 3–3.5 billion years ago.
The earliest fossil cells were until recently thought to come from 3.5 billion-year-old rocks from the Apex Chert in Western Australia (Schopf 1993). However, Brasier et al. (2002) have argued that the alleged fossils in these rocks are artifacts and not fossils. Other evidence for fossil cells exists from the 3–3.5 billion- year period (for instance, Knoll & Baghoorn 1977, and Schopf 1999 reviews the evidence). Cells had therefore likely evolved by 3.5 billion years ago, or soon afterwards.

Reference By:
THIRD EDITION of  MARK RIDLEY

Saturday, 3 March 2018

Types of Nucleic Acids


Types of Nucleic Acids
There are two types of nucleic acid DNA and RNA.

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Immunoglobulins their types, structure and functions


Immunoglobulins their types, 
structure and functions

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Nucleic acid



Nucleic acid,
Structure and their Function.


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Plasma Membrane Definition With Function




Plasma Membrane,
Functions of the Plasma Membrane,
Plasma Membrane Structure,
Fluid Mosaic Model.




Transmission of Genetic Material In Bacteria




Transmission of Genetic Material In Bacteria
Three common mechanisms of lateral gene exchange :
 Conjugation (bacterial mating systems) and their Steps
 Transformation (extracellular DNA uptake)
 Transduction (viral mediated gene exchange)
 Co-Transduction.


Friday, 2 March 2018

Zoology

Zoology is the branch of biology in which we study of over all animals.

Energy in ecosystems and their types

Energy in ecosystems and categories,
The laws of thermodynamics and their application,
Trophic levels,
The flow of energy, 
Food chain and their tropic level,
Food web.

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Plant Cell Nucleus and Nuclear Membrane


Plant Cell Nucleus including Definition Details,
Nuclear Membrane,
Function of the Nuclear Membrane,
Parts of the Nuclear Membrane,
Nucleolus.

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KARYOTYPE ANALYSIS and their Defination



KARYOTYPE ANALYSIS And their Defination,
types of techniques are used in karyotype analysis:
Classic karyotype analysis,
Spectral karyotype (SKY technique),
Formation of Karyogram.
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Carbohydrates and classification



Carbohydrates and  classification,
Structure of carbohydrates,
Characteristics of carbohydrates and
Peptidoglycans of bacterial cell wall.
This all topic is available in follwing link.

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