Genetics

Question 1:What is the effect of drug abuse on body coordination? Answer:Imbalance of hormone, unclear speech and slow reflex action. Question 2:How do the chemical substances in the drugs and alcoholic drinks affect the neurons? Answer:The movement of nerve impulses within neurons is disrupted (fast or slow). Question 3:How do drugs and alcohol influence hormone … Read more

Question 1:What is mutation? Answer:Mutation is a change that occurs spontaneously and randomly on the genes or chromosomes, which can cause a characteristic change in the child inheriting the modified genetic materials. Question 2:List three factors that cause mutation. Answer:Radioactive radiation, X-ray and toxic chemical substances. Question 3:List the advantages and disadvantages of genetic research. … Read more

Question 1:Explain the differences between the dominant allele and the recessive allele. Answer:Dominant allele would show the characteristics that it controls and hides the effects of the recessive allele. The recessive allele would only show the characteristics it controls when the dominant allele is absent. Question 2:What are sex chromosomes? Answer:Sex chromosomes are chromosomes that … Read more

Question 1:What is meant by(a) gene (b) chromosomes (c) DNA Answer:(a) A gene is a basic hereditary unit that determines an individual’s characteristics.(b)Chromosomes are fine thread-like, long and spiral structures located in the nucleus.(c) Deoxyribonucleic acid or DNA is a two twisted antiparallel polynucleotide chain forming a structure known as double helix. Question 2:Where do … Read more

Question 1:Diagram 1 shows the schematic diagram of sex determination in human being.(a) In Diagram 1, complete the sex chromosomes in gametes K and L. [2 marks](b) What is gamete L? [1 mark](c) State process B. [1 mark](d) State the sex of offspring M. [1 mark](e) Based on Diagram 1, state the percentage to get … Read more