As Biology (7401/1) Paper 1 Specimen 2014 |39 Questions| With Correct Answers.

03 . 1) Figure 3 summarises the process of meiosis. The circles represent cells and the structures within each cell represent chromosomes. Describe and explain the appearance of one of the chromosomes in cell X. [3 marks] {Ans: 1. Chromosome is formed of two chromatids; 2. (Because) DNA replication (has occurred); 3. (Sister) chromatids held together by centromere;}04 . 3) During replication, the two strands of a DNA molecule separate and each acts as a template for the production of a new strand. Figure 5 represents DNA replication. Name the enzyme shown in Figure 5. [1 mark] {Ans: DNA polymerase;}07 . 4) Which of the fatty acids, X or Y, in Figure 8 is unsaturated? Explain your answer. [1 mark] {Ans: Y (no mark) Contains double bond between (adjacent) carbon atoms in hydrocarbon chain;}07 . 1) Describe how you would test a piece of food for the presence of lipid. [2 marks] {Ans: 1. Dissolve in alcohol, then add water; 2. White emulsion shows presence of lipid;}The water potential of the blood plasma is more negative at the venule end of the capillary than at the arteriole end of the capillary. Explain why. [3 marks]