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SEX DETERMINATION The chromosomes which determine sex in the different organisms are called sex chromosomes. ‘Fhe term –sex– refers to the processes that enable species to exchange materials between homologous chromosomes. Ii causes recombination. Recombination is essential to their mechanism for reproduction. Work on inheritance of sex started after discovery of Menders ork in 1900. The discovery of sex chromosomes ...

EPIDERMIS Epidermis forms the outermost layer of cells on the primary plant body. It is present over stem. roots, leaves, flowers and fruits. In most plant. epidermis is composed of single layer of cells. But two or several layers are also found in different plants. When it is composed of single layer, it is called hypodermis. When it is composed ...

The group of cells performing some collective function is called tissue. Tissues organize the body of plant for performing different function. Many types of tissues associate with each other to form tissue system. Vascular system is an example of tissue system. The tissues have following characteristics: Tissues are composed of many cells. These cells may be of one type or ...

WATER Absorption: of water*, root hairs: .[he absorption of \safer from the soil takes place tlitimigh the root hairs. Ihe root hairs are in contact with the wateriilms on the soil particles. ‘[here is a thin lining of cytoplasm inside the root hair. This cytoplasm encloses a large vacuole filled with cell sap. The Cytoplasm and cell sap of the ...

Eucalyptus Description The leaves are leathery in texture, hang obliquely or vertically, and are studded with glands containing a fragrant volatile oil. The flowers in bud are covered with a cup-like membrane (whence the name of the genus, derived from the Greek eucalyptos well-covered), which is thrown off as a lid when the flower expands. The fruit is surrounded by a ...

Absorption Of Water In Plants Soil The complex composite mass made up of both inorganic and organic, components containing water and air is called soil. There are different amount of various components of soil. Their amount and depends upon the nature of the soil, its depth and the state of its irrigation. The ordinary garden soil has the following composition ...

Water Potential (qp) The chemical potential of water is called water potential. The total kinetic energy of the molecules is called water potential. The chemical potential of water depends on the number of water molecules. Thus it is expressed as energy per mole of water molecule. The chemical potential of pure water is taken as zero. The kinetic energy of ...

Diffusion And Factors affecting the diffusion Diffusion The movement of molecules from higher concentration to lower concentration is called diffusion. Diffusion occurs down the concentration gradient. It is a spontaneous process. Diffusion continues till dynamic equilibrium is achieved. It follows laws of thermodynamics. But it is a very slow process. The rate and the direction of diffusion of different substances ...

Colloidal System – Properties & Significance A heterogeneous mixture in which solute particles are larger than molecules or ions but cannot be seen by naked eye is called colloidal solution. A system which shows properties of colloidal solution is called colloidal system. Its example is clay in water or starch in water. The solvent is called the dispersion medium in ...

PTEROPSIDA THE WATER FERNS Occurrence Marsilea is an aquatic or semi aquatic plant. It is common in the temperate regions. It groNA in fresh water ponds and ditches in Punjab. Marsilea quadrifolia and Munilea minuta are commonly found in Pakistan. General structure The vegetative plant is a sporophyte. It is differentiated into roots, rhizome and leaves. 1.  Rhizome: The stem ...