BIOLOGY complex plant tissues Tracheids : Cells are dead, long with transverse ends, containing large vacuole. Cell walls are hard, strong. and lignified. Their main functions are to give mechanical strength and to supply water and dissolved minerals from root to the leaves.Complex tissue is composed of more than one kind of cells. They are two types, namely Xylem tissue and Phloem tissue. Tracheid Xylem tissue : Xylem tissue consists of four types of cells, namely: Tracheids, Vessels or Trachaea, Xylem fibre and Xylem Parenchyma. Vessel Vessels or Trachaea: Cells are broad and short, placed end to end to form a continuous hollow tube. Water and waterdissolved minerals are conducted from root to leaf by these cells. �Xylem fibre: These are sclerenchymatous cells. Their main function is to give mechanical strength to the plant. Xylem parenchyma: These are parenchymatous . cells. Functions of these cells are storage and conduction of food materials. Func...
Division Of Labour In Multicellular Plants : Tissue and Tissue System Tissue : In unicellular organisms a single cell does all the functions. There is no chance of division of labour on the basis of cell. In contrast, this kind of division is found in multicellular living body. In this case, it is observed that a group of cells performs the duty of manufacturing food; another group stores it, while the other group conducts the transport of food materials. There is further a group of cells that gives mechanical strenght to some organs. In many cases it is observed that a group of cells originating from a single origin remain closely attached in a place and collectively perform a similar type of function. This type of cells in a group is called tissue. In multicellular organisms division of labour is the main cause of formation of tissue. Types of Tissue : Cells of all tissues do not have the power of cell division but some of them have. Therefore tissues are of two types in terms of t...
Structural, Characteristics, Functions and Location of Connective Tissue . Structural Characteristics: The. amount of matrix is more in connective tissue but the number of cells is comparatively less. Matrix may be jelly like, soft or hard and fragile. One or more than one type of fibre and materials like calcium carbonate may remain present in matrix (Fig-5.6): Functions : Connective tissue connects muscle with muscle and bone with bone. Connective tissue may transform into skeletal tissue, fibrous tissue and. fluid connective tissue. On the basis of structure and function connective tissue is mainly of three types. As: A . Films Connective Tissue: This type of connective tissue lies below the body-integument and sparsely in muscles. In their matrix numerous fibres are present. B. Skeletal Tissue: Internal structural building tissue of the body is called the skeletal tissue. Functions : 1. This tissue forms the internal structure of the body, e.g. skeletal system. 2. It gives the b...
I got 14 out of 15 is it not good ?
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