CHROMOSOMAL BASIS OF HEREDITY
Within the nucleus of non-dividing cells are strands or string-like structures known as chromosomes. As the cell is about to divide, the chromatids become more visible as strands with bead-like structures on them. These are the chromosomes and contain genes,…
SALINITY OF THE OCEAN
Almost every known chemical element can be found in varying proportions in the oceans whose most characteristic feature is their salinity, in contrast to the fresh water of lakes and streams. All sea water of which sodium chloride or common…
THE RELIEF OF THE OCEAN
The ocean basins are in many ways similar to the land surface. There are submarine ridges, plateaux, canyons, plains and trenches. A section drawn across an ocean (Fig. 12.4) illustrates the typical submarine relief features. 1) The continental…
EXPLORING THE OCEANS
The oceans occupy more than 70 per cent or 364 million sq km (140 million square miles) of the earth’s total area of 510 million sq km (197 million square miles). They have tremendous development potential. Besides being a source…
Study Guide
