types of structures and their organisation level

Living Beings are Organised - Organisation refers to a kind of structure or system or situation where the smaller components become arranged into larger ones in a hierarchical order of complexity, to co-ordinate with one another in performing common functions or achiev..

The molecules of various chemical substances in a specific proportion become organised into protoplasm - the physical basis of life. The protoplasm gets organised into cells, which represents the structural and functional unit of life. A living organism may have a sin..

In multicellular organisms, cells having a common origin, group to form tissue. The cells in a tissue may be similar in structure to common functions (as in epithelium) or dissimilar in structure performing different functions (as in blood). There are different types ..

Thus when carbon having different chain lengths and structures combines with different elements it leads to the formation of a large number of compounds. Isomerism The unique feature of the carbon-carbon bonding has also led to the formation of compounds that can have the same molecular f..

The characteristic structure of an ecosystem is obtained by the systematic physical organisation of the abiotic and biotic components of that particular ecosystem. The two main structural features of any ecosystem are its 'species composition' and 'stratification'. An ..

fig 17.4 - Collagen triplex helix In globular proteins e.g., haemoglobin the polypeptide chains consist partly of helical sections which are folded about the random cuts to give it a spherical shape. The primary, secondary and tertiary and quarternary levels of haemoglobin structureh..

Structure of Proteins - Secondary Structure - This structure explains the folding of a polypeptide chain. Two different types of secondary structures are observed. a -Helix The a -helix model postulated by Linus Pauling in 1951 was based purely on t..

fig. 1.1 Levels of Organisation..

Arrangement of Electrons in an Atom (Bohr-Bury Scheme) - Electrons revolve around the nucleus in different energy levels or shells and each shell is associated with definite energy. The energy of the K shell is the least while those of L, M, N and O shells increases progressively. We also..

Structure of Chromosomes - The chromatin material just before cell division forms into chromosomes. Each chromosome is made up of two longitudinal strands called the chromatids. Structure of Chromosome Each chromatid has a double helical DNA molecule. The two chromatids are held..