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...As meiosis begins, the chromosomes start to become visible. At this stage they have produced replicas of each other. The centrioles separate and move to opposite poles (ends)... More

...The chromosomes are clearly visible. They each consist of two threads called chromatids, each an exact copy of the parent chromosome. Chromatids are joined... More

...need minerals from the soil. Excretion Waste products must be... Movement Animals move to find food and away from predators and plants move towards light... More

...Protoplasm Consists of cytoplasm and nucleus. Cytoplasm Jelly like substance where chemical reactions take place and other parts are embedded... More

...DNAThe molecule which contains genes. It's shaped like a double helix (a spiral) Chromosomes Found in the cell nucleus: X- shaped things made up of... More

...Diffusion is the seemingly random movement of a substance from where these particles are in high concentration to where there are fewer. The diffusion... More

...main sources of water pollution: See also:Leaching / Eutrophication The impact of human activities on the earth has become noticeable and significant during... More

...Leaching describes the "washing out" from soils any soluble chemicals that are not "bound" to the soil particles. It occurs as excess... More

...1. Cerebrum- (consisting of the two cerebral hemispheres) A small part of the cerebrum determines what we hear. Another section interprets what we... More

...the nerve impulses (at the left of diagram above). Synapses are... Sensory Neurone The nerve impulses travel from left to right in this diagram of a sensory neurone... More