• Q & A

    Q & A OF ANATOMY OF FLOWERING PLANTS

    Q1) Name the associated structure of companion cell. Ans: Sieve tube cell Q2) Name an enucleated plant cell. Ans: Sieve tube cell Q3) Name the conductory elements of xylem. Ans: Tracheary elements- Tracheids and Vessels (tracheae)  Q4) What is periderm? Ans: Phellogen, Phellum and Phelloderm are collectively called as Periderm Q5) What is annual ring? Ans: Springwood and autumn wood that appear as alternate concentric rings constitute an annual ring.  Q6) Name the meristem which is responsible for growth in diameter of the cortex. Ans: Cork Cambium Q7) What is intrafascicular cambium? Ans: Cells of cambium present between primary xylem and primary phloem. Q8) What is interfascicular cambium? Ans: The…

  • Human anatomy,  Zoology

    NERVOUS SYSTEM

    Nervous system is the most complex system in human. Its uniqueness is due to the vast complexity of thought process and control action it can perform. It co-ordinates physiological functions in human. Nervous tissue originates from ectoderm and is specialized for receiving stimuli and transmitted message. The nervous tissue consists of highly specialized cells called the neurons. Thus neurons are functional unit of nervous system. The detailed structure of a neuron is shown in Figure. A neuron is mainly divided into two parts: 1) Cell body or cyton and 2) Cell process. Cyton It is broader part of neuron which contains uninucleated cytoplasm. Except for centriole, all type of cell organelles…

  • Biology,  Human anatomy

    HUMAN DIGESTIVE SYSTEM

    Digestion involves the breaking of complex organic food molecules into simpler one by hydrolysis. Carbohydrates, proteins, fats and nucleic acids are large complex organic food molecules. They are insoluble and polymeric in nature. During digestion different enzymes helps in the breakdown of these complex polymers into soluble monomers which are required for energy generation. The different steps of digestion involve: Movement of food through the alimentary tract Secretion of digestive juices and digestion of food Absorption of water, various electrolytes, vitamins and digestive end products. Human digestive system mainly consists of two parts: 1) Alimentary tract and 2) secretory glands Alimentary tract: It provides continuous supply of nutrients, vitamins, electrolytes…

  • Biochemistry

    DIGESTIVE SYSTEM

    DIFFERENT MODE OF DIGESTION IN ORGANISMS The collective processes by which a living organism takes food which are necessary for their growth, maintenance and energy needs is called nutrition. The chemical substances present in the food are called nutrients. It is important to know the different modes of nutrition in all living organisms in order to understand energy flow within the ecosystem. Plant produces high energy organic food from inorganic raw materials. They are called autotroph and the mode of nutrition is known as autotrophic nutrition. Animals feed on those high energy organic food, are called as heterotrophs and their mode of nutrition is known as heterotrophic nutrition. Heterotrophic nutrition…

  • Botony

    INFLORESCENCE

    The arrangement of flower on floral axis is called inflorescence. Racemose – In this type of inflorescence the main axis continues to grow and does not terminate in a flower and give off flower laterally in acropetal manner where old flowers are arranged toward base and young flowers are at tip. When peduncle is broad then flowers are centripetally arranged. This is of following different types : Raceme – When peduncle (main axis) is elongated and flowers are pedicellate. eg. Radish, characteristic feature of cruciferae family When peduncle is branched and each branch bear pedicellated flowers like racemose and are arranged in acropetal manner known as compound raceme or panicle. eg.…

  • Biology,  Botony

    LEAF (PHYLLOPODIUM)

    The leaf is a lateral generally flattened structure borne on the stem. The leaves develop from the nodes. Their main function is photosynthesis and food making, axillary buds are found in its axil. All the leaves of a plant are known as phyllome. Axillary bud later develops into a branch. Leaves originated from shoot apical meristem and are arranged in acropetal order. Leaf is divided into 3 main parts : Leaf base (Hypopodium) – Leaves are attached to stem by leaf base. In some plants, leaf base becomes swollen and is called pulvinus which is responsible for sleep movement e.g., Cassia, mimosa, bean. In some plants, leaf base expands into…

  • Botony

    STEM

    Stem is a part of the plant which lies above from surface of soil i.e. it shows negative geotropic growth. It has nodes and internodes. Branches, leaf, flower bud and bracts are developed from nodes. Stem arises from plumule. FORMS OF STEM Caudex: It is unbranched, erect, cylindrical stout stem and marked with scars of fallen leaves. Crown of leaves is present at the top of plant. eg.: Palm Culm: Stem is joined with solid nodes & hollow internodes. eg. Bamboo (Graminae) Excurrent: The branches arise from the main stem in acropetal succession and the tree assumes a cone-like appearance e.g. Pinus, Eucalyptus, Casuarina, etc. Decurrent (Deliquescent): The lateral branches…

  • Botony

    NITROGEN METABOLISM

    All the living organisms are basically composed of carbon, hydrogen, oxygen, nitrogen and many other forms of chemical elements. These elements contribute to finally organize various biomolecules present in a cell. Nitrogen is next to carbon in importance in living organisms. In a living cell, nitrogen is an important constituent of amino acids, proteins, enzymes, vitamins, alkaloids and some growth hormones. Therefore, study of nitrogen metabolism is absolutely essential because the entire life process is dependent on these nitrogen-containing molecules. MOLECULAR NITROGEN Nitrogen is primarily present in the atmosphere freely as dinitrogen or nitrogen gas. It is present in the combined form as Chile saltpetre or sodium nitrate and Chile…

  • Biochemistry

    BIOTECHNOLOGY

    The word biotechnology has come from two words, bios (meaning biology) and technology (meaning technological application). Thus biotechnology is defined as the industrial application of living organisms and their biological processes such as biochemistry, microbiology, and genetic engineering, in order to make best use of the microorganisms for the benefit of mankind. Biotechnology is applied in many areas to produce foods and medicines, in the development of new diagnostic tools, gene therapy, and DNA finger-printing for forensic purposes. Applications of Biotechnology 1. Health and medicine Fighting infectious diseases: Biotechnology is used extensively in the study of infectious diseases such as SARS (Severe Acute Respiratory Syndrome), and influenza. As a result, more…