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MINISTRY OF DEFENCE

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  MINISTRY OF DEFENCE. Establishment Of National University In Islamabad Total position. 29 Domicile , All over Pakistan    Qualification  intermediate to bachelor positions . Project Engineer(Civil) account Officer  supervisor assistant office boy     How to apply.   Apply online through the link https://www.fgei-cg.gov.pk/nup-rec.php   Last date to apply  02 April 2023. No TA/DA Fo Interview 
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Introduction and BRANCHES OF BIOLOGY

Introduction and BRANCHES OF BIOLOGY Biology The study of the living thing is called biology. It helps us to understand nature. The biologist study living things but they also study the non living things which affect the living things. ~ life and its Characteristics~   The biologists explain only how life works. Life has following these characteristics A.  The living organisms are highly organised B. They have complex structure. C.their body is composed of one are more cells D. They contain genetic programs of their characteristics E.They can produce and use energy F.Many chemical Reaction takes place in them. G.They can grow in size. H.They maintain constant internal environment. I.They produce offspring. J.They show response to change change in environment. 2.Branches oF BIOLOGY Biology is a vast subject,therefore,biology is divided into many branches for study. A.Embryology The study of the development of an embryo till it is hatched or borne is called embryolo
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Structure of chromosomes:

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Structure Of Chromosomes: Structurally the chromosomes consist of following parts 1. Chromatids 2.centromere or primary construction 3. Chromonema and chromomeres 4. Secondary construction or nuclear organizer 5. Telomere 1 Chromatids Chromosomes consist of two thread like structure called chromatids. 2. Centromere or primary construction: The chromatids are connected with each other by a small round structure called centromere (  In centromere the proteins are present which provide attachment with microtubules are called kinetochore. The position of the centromere is specific in the chromosomes. 3: chromonema and chromonemata: The chromatids are composed of two thin highly coiled filaments called chromonema or chromonemata. Each chromonema contains a double stranded DNA. Both chromonema are coiled in spiral manner and they also contain swellings on their surface called chromomeres ( structural subunit of chromosomes.the arrangement of chromomere structure
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What are chromosomes?

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Chromosome Chromosome During cell division the chromatin material change into thread like structure called chromosome. Chromosomes are also called physical basis of hereditary. On the chromosomes small bodies are located call genes. There are thousands of genes are present in an organisms.Genes are the unit of heredity. These genes contain hereditary character which are transfered from one generation to another by the help of chromosomes. Chromosomes were discovered by a biologist waldyer in 1876. After that in  1908 Sutton identified the function of chromosomes,that they take part in the transfer of hereditary characters.      ( Next post will be about Structure of chromosomes)
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Neurotransmitters and receptors

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Neurotransmitters and receptors Did you know there are billions of neurons—and trillions of synapses—in your amazing brain? ^1 1 start superscript, 1, end superscript  (No wonder you can learn anything, including neurobiology!) Most of your synapses are  chemical synapses , meaning that information is carried by chemical messengers from one neuron to the next. In the article on synapses, we discussed how synaptic transmission works. Here, we’ll focus on  neurotransmitters , the chemical messengers released from neurons at synapses so that they can “talk” to neighboring cells. We’ll also look at the receptor proteins that let the target cell “hear” the message. Neurotransmitters: Conventional and unconventional There are many different kinds of neurotransmitters, and new ones are still being discovered! Over the years, the very idea of what makes something a neurotransmitter has changed and broadened. Because the definition has expanded, some recently discovered n
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Excretion in Invertibrate,(Excretion in Planaria, Excretion in Earthworm,Excretion in Cockroach)

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Excretion in Invertibrate Excretion in Planaria Habitat : Planaria is a fresh water invertebrate.   Excretory product: planaria remove ammonia and it is ammonotlic. This excretion occurs by two methods, diffusion, specialized excretory system. Excretory organs: Planaria has simple tubular excretory system called protonephiridia. Protonephridia arranged in two longitudinal trunk one on each side of the body. Each track consists of a network of tubules without internal openings. These tubules divide into small branches which open in flame cells. Tubules open on the outside by small opening called nephridiophores. Structure of flame cell: Flame cells are club shaped hollow cells. Each flame cell contains nucleus, cytoplasm and internal cavity. Group of cilia is present in the cavity. Cilia perform a movement like a flame of candle. Flame cells also has many cytoplasmic elongations. Mechanism of excretion: Flame cells absorb wastes and push them into the cavit
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Waste Products Of Animals

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Nitrogenous Wastes Of Animal: Waste Products Of Animals: The nitrogenous wastes are urea,ammonia and uric acid . These all wastes are not removed by the same animal. These wastes are produced and excreted by different animal which are living in different habitats. The type of nitrogenous waste and their excretion depend upon the habitat of an animal. 1.Ammonia (NH3): It is the excretory product of aquatic animals ,developes by the break down of amino acids,harmful to the living cells,excreted by diffusion and highly soluble in water. About 500 ml of water is needed to remove one gram of ammonia . Animals those excrete ammonia are called ammonotelic . Examples: Eartworm, protozians, sponges and fishes etc. 2.Urea {CO (NH2)2}: It is the excretory products of mostly land animals ,produced by the liver from ammonia,less toxic than ammonia and can be store in the body for short time. One gram of urea require 50 ml of water for excretion. Animals those remove urea are
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