1 Diagram 1 shows a rat that being used in an experiment. What is the suitable method to manage this biological waste? flag bookmark A Decontaminated by autoclave before disposal. B Place into a special bin for sharp material. C Wrapped carefully in absorbent material, packed into biohazard plastic bag and frozen. D Packed in autoclave resistant biohazard plastic bags, sterilized and placed into biohazard bin. T4 Chapter 1.2 Safety and Rules in Biology Laboratory An animal carcass is category C biological waste. It is wrapped carefully in absorbent material, packed into a biohazard plastic bag and frozen. Autoclaving is for liquid waste and non-sharp solid waste, and the sharps bin is for needles and scalpels.
2 Diagram 2 shows a component in a cell. Which of the following explain the function of the component? flag bookmark A A site that generate energy. B Forms spindle fibre during cell division in animal cells. C Processes, modifies, packs and transport chemicals such as protein. D Synthesises and transports glycerol and lipids and carry out detoxification of drugs. T4 Chapter 2.1 Cell structure and function The structure is a pair of centrioles, each made of nine groups of microtubules arranged at right angles. Centrioles form the spindle fibres during cell division in animal cells.
3 Diagram 3 shows the process that has occurred in living organisms. Which of the following describes the process that occurs as in the diagram below? flag bookmark A This process does not require energy. B This process occurs until a dynamic equilibrium is reached. C Carrier protein change shape to allow glucose molecules to pass through the carrier proteins and to enter the cell. D Phosphate bond provides energy and change the shape of the carrier protein, then sodium ion is transported out of a cell. T4 Chapter 3.2 Concept of Movement of Substances Across a Plasma Membrane The diagram shows the sodium-potassium pump, which is active transport. ATP is broken down to ADP + Pi, and the energy from the phosphate bond changes the shape of the carrier protein so that sodium ions are pumped out of the cell against the concentration gradient. Option C describes glucose entering by facilitated diffusion, which is not what the diagram shows. (Note: the answer scheme gives C; on checking, our AI thinks D is more accurate, so both D and C are accepted.)
4 Mr. S had diarrhoea and went to the clinic to see a doctor. Which of the following is one of the medicines given by the doctor? flag bookmark A Liposomes B Saline solution C Isotonic drink D Oral rehydration salt T4 Chapter 3.4 Movement of Substances Across a Plasma Membrane and Its Application in Daily Life Diarrhoea causes the body to lose a lot of water and salts. Oral rehydration salt is taken by mouth to replace the lost water, salts and glucose and prevent dehydration.
5 Which of the following is true about the difference between saturated fat and unsaturated fat? | | Saturated fats | Unsaturated fats | |---|---|---| | A | Coconut oil | Margarine | | B | Liquid at room temperature | Solid at room temperature | | C | Only have single bond between carbon | Have at least one double bond | | D | Can receive additional hydrogen atom | Cannot receive additional hydrogen atom | flag bookmark A Coconut oil – Margarine B Liquid at room temperature – Solid at room temperature C Only have single bond between carbon – Have at least one double bond D Can receive additional hydrogen atom – Cannot receive additional hydrogen atom T4 Chapter 4.4 Lipids Saturated fats have only single bonds between the carbon atoms of their fatty acids, while unsaturated fats have at least one double bond. Saturated fats are solid at room temperature, and it is unsaturated fats that can take up extra hydrogen atoms. Margarine is made by hydrogenating oil, so it is not an example of unsaturated fat.
6 Diagram 4 shows a mechanism of enzyme action. What is X? flag bookmark A Product B Enzyme C Complex enzyme product D Complex enzyme substrate T4 Chapter 5.2 Enzyme X shows the substrate fitted into the active site of the enzyme, forming an enzyme-substrate complex, as in the lock and key hypothesis. The products are then released and the enzyme is unchanged.
7 Diagram 5 shows a graph of the effect of pH on the rate of enzyme reaction. Which of the following is the optimal pH for enzyme reactions in the stomach? flag bookmark A pH 2 B pH 7 C pH 8.6 T4 Chapter 5.2 Enzyme The stomach is very acidic because of hydrochloric acid, and the stomach enzyme pepsin works best at about pH 2, matching the first peak of the graph.
8 Diagram 6 shows a stage in mitosis. What is the chromosomal behaviour that can be seen in this stage? flag bookmark A Chromosomes become aligned in a single row on the equatorial plane B Sister chromatids separate and are attracted to the opposite pole C Chromatin starts to shorten and thicken to form a chromosome structure D Homologous chromosome separate and are attracted to the opposite pole T4 Chapter 6.2 Cell Cycle and Mitosis The diagram shows anaphase of mitosis: the spindle fibres pull the sister chromatids apart towards opposite poles. Homologous chromosomes separate only in meiosis I.
9 Diagram 7 shows an Orang Utan or the scientific name is *Pongo pygmaeus*. The number of chromosome in the liver cell is 48, how many chromosome in its pancreatic cells? flag bookmark A 48 B 24 C 96 D 46 T4 Chapter 6.2 Cell Cycle and Mitosis Liver and pancreatic cells are both somatic (body) cells formed by mitosis, so they have the same diploid number of chromosomes, 48.
10 Diagram 8 shows a yogurt that undergone fermentation. How much energy that being produce from the process? flag bookmark A 150 kJ B 210 kJ C 1898 kJ D 2898 kJ T4 Chapter 7.3 Fermentation Yoghurt is made by lactic acid fermentation by bacteria. Lactic acid fermentation of one mole of glucose releases only about 150 kJ of energy. Alcohol fermentation releases about 210 kJ and aerobic respiration about 2898 kJ.