SAQs – Short-Answer Questions.

Date: 2015-10-07; view: 559.

1. Name the four most common elements found in living organisms (4).

2. Name one element other than any of those mentioned in (1) that is required by living organisms and describe it's function (2).

3. Draw a diagram showing water molecules held together by a hydrogen bond (3).

4. What are hydrogen bonds? (1)

5. Explain how salt gets dissolved in water (2).

6. Distinguish between organic and inorganic compounds (2).

7. Identify glucose, amino acid, ribose, fatty acid from the following diagrams (4):

a) b) c) d)

8. The diagram shows the basic structure of an organic molecule:

a) Name the molecule (1)

b) State what is represented in the diagram by the letter R (1)

c) Draw a simple diagram to show how 2 of these molecules are linked together (3)

9.

a. What is the structure of a lipid molecule? (2)

b. State one function of lipids in living organisms (1)

10. Distinguish between the following pairs of words (4):

a. Fat and oil

b. Starch and glycogen

c. Condensation and hydrolysis

d. Hydrophobic and hydrophilic

11. Write a word equation for each of the following (3):

a. Hydrolysis of maltose

b. A chemical reaction that forms a triglyceride

c. How monosaccharides are converted into polysaccharides

12. List one example of each of monosaccharide, disaccharide and polysaccharide (3).

13. Outline the difference in functioning of glycogen and cellulose (2).

14. What are the functions of lipids? (3).

15. Compare the use of carbohydrates and lipids in energy storage (4).

16. List the nucleotide bases of DNA and RNA (2)?

17. List 3 components found in all nucleotide molecules (1).

18. How are the bases in a double strand of DNA held together (1).

19. Give a synonym for the term “nucleoside monophosphate” (1).

20. Distinguish between a nucleoside and a nucleotide (2).

21. If one strand of DNA has the base sequence AATCCG, what will be the corresponding base sequence of its complementary strand (1).

22. A transcribing DNA strand contains the base sequence CGGAATCGT. What will be the base sequence in the mRNA transcribed from it? (1)

23. What is the role of tRNA? (1)

24. What is central dogma of biology? (3)

25. Work out which amino acid has the codon CAU. Work out what the DNA sequence coding for this codon is. Give tRNA anticodon sequence for this codon (3).

26. Refer to the following figure when answering the following questions (4):

a. State what molecule is represented

b. State whether the molecule would be found in DNA or RNA

c. State the part of the molecule to which phosphates bind

d. Identify the part of the molecule which will be used to create a phosphodiester bond

27. Figure below shows a short section of DNA before and after replication. If the nucleotides used to replicate the DNA were radioactive, which strands in the replicated molecules would be radioactive? (2)

GCTACGCTAC (1) GCTAC (3)

CGATG CGATG (2) + CGATG (4)

28. What kind of bond is formed between two adjacent nucleotides of a single DNA strand? (1)

29. Draw and label a simplified diagram of a nucleotide showing 5' and 3' ends. (5)

30. Explain the terms universal and degenerate as they relate to the genetic code (2)

31. What does one gene-one polypeptide theory say? Are there any exceptions? (3)

32. A nucleic acid is composed of nucleotides. What is the composition of each of the following (4):

a. A gene

b. A codon

c. A nucleotide

d. A polypeptide

33. Determine 2 possible DNA sequences that could code for Phe-Ile-Val-Leu (2)

34. What is the difference between free ribosomes and RER-bound ribosomes in terms of the final products that they synthesize? (2)

35. List 4 stages of translation process (4).

36. Define enzyme and active site (2).

37. Define photosynthesis (1).

38. What are the two main phases of photosynthesis? What is their role? (4)

39. What is sunlight? (1)

40. What is the main photosynthetic pigment? (1)

41. What are the ways one can measure the rate of photosynthesis? (3)

42. Define cell respiration (1).

43. What is a simplified formula of glycolysis? (3)