Sugar Atoms

ATP, easy as 123.

ATP is the renewable energy source for our cells. It consists of 3 phosphates, a sugar and an adenine ring. The bond between the last 2 phosphate groups is a weak unstable bond. When broken, ATP is changed to ADP and a phosphate, releasing energy to be used in cellular reactions. ATP stores regenerate when energy from respiration reactions is used to reattach the phosphate a an ADP. ATP is soluble and hence easily transported. Every chemical reaction in every cell requires or produces ATP molecules. Most ATP is made in the mitochondria and diffuses into the cytoplasm and to membranes. ATP is used in movement, locomotion, structure, metabolism, synthesis, active transport, cellular signalling, DNA and RNA synthesis. 

Certain chemicals have the ability to interfere with cell metabolism.

• Carcinogens include asbestos fibres, chemicals in cigarette smoke, electromagnetic radiation (UV, X-ray, microwaves, infa-red) and free radicals found in food preservatives (can be counter-acted by antioxidants). 
• Mutagens that cause cancer contribute to the formation of oncogenes. These genes often code for membrane proteins that mimic growth factor receptors, stimulating growth and causing uncontrollable cell division.
• Carbon monoxide is a toxic gas that binds to haemoglobin, meaning it cannot carry the oxygen our cells require. 
• Carbon monoxide, cyanide and hydrogen sulfide denature enzymes involved in metabolic pathways. 
• Penicillin attacks a step in the synthesis of bacterial cell walls, acting as an antibiotic with a specific target. 
• Mercury (used in thermometers) can be converted by bacteria to methyl mercury. This enters and accumulates in the food chain. 
• Herbicides and insecticides kill weeds and protect plants respectively, however both contribute to chemical pollution of soil and atmosphere.
• Preservatives which are used to create long-life foods were initially used without much thought. However, they cause many different allergic reactions.
• Thalidomide was used to treat nausea in pregnant women, and their children were born with parts of their limbs missing. (Refer to image)
• Overuse of antibiotics causes resistant strains to thrive.