D. Adenine (Total 1 mark)

Transcription

1 1. Which is the structure of glycerol? A. B. O O O O. D. O O O 2. In the structure of DNA what binds with cytosine? A. Deoxyribose B. Ribose. Thymine D. Adenine 3. Which diagram correctly illustrates a dipeptide? A. O O B. O O N N N N O O. O D. O O N N N N O O 1

2 4. What are the components of a DNA nucleotide? A. Deoxyribose, a phosphate and one of the bases: adenine, cytosine, guanine or thymine B. Ribose, a phosphate and one of the bases: adenine, cytosine, guanine or uracil. Deoxyribose, a nitrate and one of the bases: adenine, cytosine, guanine or thymine D. Ribose, a nitrate and one of the bases: adenine, cytosine, guanine or thymine 5. What is the correct sequence of chemicals produced in the anaerobic respiration pathway? A. Lactate pyruvate ethanol B. Ethanol pyruvate glucose. Glucose lactate pyruvate D. Glucose pyruvate lactate 6. What type of bond holds the complementary base pairs together in a double helix of DNA? A. ovalent bonds B. Peptide bonds. Glycosidic bonds D. ydrogen bonds 2

3 A. Lactate pyruvate ethanol B. Ethanol pyruvate glucose. Glucose lactate pyruvate D. Glucose pyruvate lactate 7. Aerobic respiration involves conversion of glucose into pyruvate and conversion of pyruvate into carbon dioxide and water. Where do these processes occur in a eukaryotic cell? Where glucose is broken down into pyruvate Where pyruvate is broken down into carbon dioxide and water A. ytoplasm ytoplasm B. ytoplasm Mitochondrion. Mitochondrion ytoplasm D. Mitochondrion Mitochondrion 3

4 8. Which graph shows the effect of increasing carbon dioxide concentration (O2) on the rate of photosynthesis? A. B.. 4

5 D. 5

6 9. Which two colours of light does chlorophyll absorb most? A. Red and yellow B. Green and blue. Red and green D. Red and blue 6

7 10. Which substance is a base found in RNA? A. Ribose B. Thymine. Adenosine D. Uracil 7

8 11. What enzyme is used in transcription but not in translation? A. DNA polymerase B. elicase. Protease D. RNA polymerase 8

9 12. A certain gene in a bacterium codes for a polypeptide that is 120 amino acids long. ow many nucleotides are needed in the mrna to code for this polypeptide? A. 30 B D

10 Rate of photosynthesis Topic 2 Past Exams Questions 13. Which limiting factor of photosynthesis is shown below? A. Increasing carbon dioxide concentration B. Increasing temperature. Increasing light intensity D. Increasing humidity 10

11 14. Which row in the table describes the first stage of cellular respiration? Substrate Location Product Product A. pyruvate mitochondria oxygen water B. pyruvate cytoplasm carbon dioxide ATP. glucose mitochondria pyruvate water D. glucose cytoplasm pyruvate ATP 11

12 15. Where in eukaryotic cells is glucose broken into pyruvate, to release energy for use in the cell? A. hloroplast B. ytoplasm. Mitochondrion D. Nucleus 12

13 16. What is the maximum number of fatty acids that can be condensed with glycerol? A. One B. Two. Three D. Four 13

14 17. What is responsible for the conservation of the base sequence during DNA replication? A. DNA polymerase working on one strand at the same time. B. Unpaired bases always attracting their complementary nucleotides.. DNA helicase and polymerase are complementary. D. Both strands are identical to each other. 14

15 18. The diagram below represents DNA replication. Some of the bases are indicated. In which direction is the replication fork moving and which bases would be needed to replicate the section of DNA shown? Direction of movement of replication fork Bases needed A. Left to right U, G and B. Right to left U, G and. Left to right T, G and D. Right to left T, G and 15

16 19. What would be the effect of increasing temperature on the rate of photosynthesis in a green plant? A. It increases constantly. B. It increases up to a point and then remains constant.. It increases up to a point and then decreases. D. It remains constant. 16

17 20. What causes water to have a relatively high boiling point? A. ydrogen bonds between water molecules B. ydrogen bonds between hydrogen and oxygen within water molecules. ohesion between water molecules and the container in which the water is boiled D. ovalent bonds between hydrogen and oxygen within water molecules 17

18 21. Which of the following substances are organic? I. Lipids II. Water III. arbon dioxide A. I only B. II and III only. I and II only D. I, II and III 18

19 22. During the process of replication, which bond(s) in the diagram of DNA below is/are broken? A. 3 B. 4, 5. 1, 2, 6, 7 D. 1, 7, 4, 5 19

20 23. Which of the following could be a function of a membrane protein? A. Energy storage B. Enzymatic activity. Oxygen uptake D. Thermal insulation 20

21 24. The diagram below represents an animal cell. Which processes occur in the locations labeled? Transcription Translation Respiration A. II III I B. III II I. II III IV D. III II IV 21

22 25. ow would the following DNA sequence, AGTTGATGGA, be transcribed? A. UGAAGUAGU B. TGAAGTAGT. AGTTGATGGA D. AGUUGAUGGA 22

23 26. Why do leaves of plants look green? A. Most of the green light is absorbed by chlorophyll and most of the red and blue light is reflected. B. Most of the blue light is absorbed by chlorophyll and most of the red and green light is reflected.. Most of the red light is absorbed by chlorophyll and most of the green and blue light is reflected. D. Most of the red and blue light is absorbed by chlorophyll and most of the green light is reflected. 23

24 27. Which molecule is a monosaccharide? A. Ribose B. Glycogen. Amylase D. Glycerol 24