Yes, there is growing evidence that cognitive impairment is associated with cigarette smoking.
Answer: c) the human genome contains approximately 25,000 genes
e) there are approximately three billion base pairs in the human genome
Most enzymes do in fact work on a single substrate in most cases, this is because of the enzyme - substrate specificity. Certain reactant molecules acting as substrates can only fit in the "lock" of particular enzymes and undergo a conformational change and result in Unique products to be released after the reaction has occurred.
