Medical Laboratory Science (Applied Learning) Subject

AP 84-205-00 (11)

2011-13 Cohort

Assessment Task 3:

Test on Applied Immunology, Genetics & Molecular Biology, Molecular Diagnostic Techniques

Time Allowed: 1 hour Date: April 21, 2012 (Saturday) Time: 1:15 - 2:15 p.m. Instructions 1. This examination paper comprises 12 pages (including cover page). 2. Total marks for this paper is 100. This paper consists of 3 sections:

Section A: Multiple choice questions (30%) Section B: Fill-in-the-blank questions (30%)

Section C: Short question (40%) 3. Answer ALL questions in English and write in the spaces provided. 4. Make sure that you write your name, class code and student number in the space

provided.

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SECTION A: Multiple choice questions (3 marks each; Total: 30%) 1. Which of the following human characters is an example of polygenic trait?

A. Color blindness B. Earlobes C. Eye color D. Height E. Tongue rolling

2. What is the karyotype of a male?

A. 22, XX B. 22, XY C. 23, XY D. 46, XX E. 46, XY

3. Which of the following molecules is NOT a class of antibody?

A. IgA B. IgB C. IgD D. IgG E. IgM

4. Which of the following cells could be activated by T cells to destroy phagocytosed

microbes? A. Antibodies B. Blood platelets C. Erythrocytes D. Macrophages E. Mast cells

5. _________________ is NOT the non-specific defense?

A. Antibodies B. Complement proteins C. Lysozyme D. Phagocytes E. Skin and mucous membrane

6. Which of the following descriptions about mRNA is TRUE?

A. mRNA consists of adenine (A), thymine (T), guanine (G) and cytosine (C) B. mRNA is a double-strand molecule C. mRNA is formed during transcription D. mRNA is formed during translation E. mRNA is found only on eukaryotic cells

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7. Which of the following statements BEST describes the secondary immune response in an individual after vaccination?

I. Antibodies are made quickly and in great amounts II. Antibodies production lasts longer than in a primary response III. Both B and T cells involves in production of antibodies IV. B cells become plasma cells

A. I and II B. II and III C. I, II and III D. I, II and IV E. All of the above

8. Which of the following BEST describes the processes X and Y? DNA mRNA Protein X Y

A. X is replication and Y is transcription B. X is replication and Y is translation C. X is transcription and Y is replication D. X is transcription and Y is translation E. X is translation and Y is transcription

9. Which of the following statements BEST describes the function of RNA polymerase in

transcription? A. To synthesize DNA with mRNA as the template B. To synthesize DNA with tRNA as the template C. To synthesize mRNA with DNA as the template D. To synthesize rRNA with mRNA as the template E. To synthesize tRNA with mRNA as the template

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10. Which of the following sequences BEST describes the orders of experimental steps in RFLP?

I. Addition of radioactive probe II. Gel electrophoresis III. Hybridization IV. Southern blotting V. Addition of restriction enzymes VI. Visualization of DNA fragments

A. I III IV II V VI B. III II I V VI IV C. V II IV I III VI D. II I V IV VI III E. IV III I II VI V

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ANSWER SHEET Student Name: (in block letter) Class: HKUSPACE Student Number: (MLS_ApL subject) SECTION A: Multiple choice questions (3 marks each; Total: 30%)

1 6 2 7 3 8 4 9 5 10

SECTION B: Fill-in-the-blank questions (30%) 1. State THREE characteristics of the specific immunity in human. (3 marks)

________________________________ ________________________________ ________________________________

2. What are the differences between humoral and cell-mediated immunity? (6 marks)

Humoral-mediated immunity Cell-mediated immunity Mechanism

Cell type

Mode of action

3. (a). What are the SEVEN sites for regulation of gene expression? List THREE of them. (3

marks)

(b). At which step would the regulation of gene expression be the most effective? (1 mark)

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4. The diagram summarizes the processes of gene expression:

(a). Name the processes of A, B and C? (3 marks) A: ____________________________ B: ____________________________ C: ____________________________

(b). Which process(es) take(s) place in the nucleus? (1 mark)

5. The diagram shows the structure of a nucleotide:

A

C B

(a). Only component A has phosphorus atom. Name the components (A, B and C): (3 marks) A: ____________________________ B: ____________________________ C: ____________________________

(b). State TWO differences between DNA and RNA. (4 marks)

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6. Below is the sequence of a DNA template strand for transcription:

5’-ACCGCGACAATCAAGGGCTGCGGTGCGGACCTAACATCGGTGCGA-3’

Write down the sequence of the transcribed mRNA. (3 marks)

7. Two families (Chan’s and Chow’s) claimed to be the biological parents of a child (Tom).

The diagram shows the result of RFLP analysis for the DNAs isolated from each member of 2 families and Tom:

Who are Tom’s biological parents? _________________________ (3 marks)

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SECTION C: : Short questions (40%) 1. The diagram summarizes the processes during an inflammatory response:

Cell X

D B

Cell Y

C

A

(a). Arrange the processes (A-D) in the correct order of occurrence. (1 mark)

(b). What are the signs of inflammation? List THREE of them. (3 marks)

(c). Cell X is responsible for the release of histamine. (i). Name the cell X. _____________________ (1 mark) (ii). What is main function of histamine in the inflammation? (2 marks)

(d). Name and describe the process by which cell Y helps to remove pathogen in the inflammatory response. (3 marks)

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2. A normal DNA sequence and two mutant sequences (A and B) of a gene are shown below:

Normal sequence: ATG TTT CGT GGT GAT GCC TAC CCC GCC Sequence A: ATG TTC CGT GGT GAT GCC TAT CCC GCC Sequence B: ATG TTT CGT GGT GAT GCC TAA CCC GCC

(a). What is meant by “point mutation”? (2 marks)

(b). What kinds of point mutation present in sequences A and B? Name them. (3 marks)

(c). By using the table of genetic code provided, briefly describe what the possible effect

of each mutation in (a) on protein synthesis? (3 marks)

(d). Mammalian cells have several DNA repair mechanisms to correct a mutation. Suggest TWO of them. (2 marks)

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3. The photograph shows the karyotype of a child who suffers from a genetic disease:

(a). What is the sex of this child? Briefly explain your answer. (2 marks)

(b). What is the abnormality found from the karyotype of this child? (2 marks)

(c). What disease does the child have? Name the disease. (2 marks)

(d). One of the causes for this disease is non-disjunction. Briefly describe how does non-

disjunction cause this disease? (4 marks)

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4. The pedigree shows the inheritance of a hereditary disease in a family:

The disease is caused by a pair of alleles (A for normal allele and a for disease allele). (a). What is the type of inheritance of this disease? (2 marks)

(b). What are the genotypes of individuals 1, 2, 3 and 4? (4 marks)

(c). If the individual “3” marries with an affected female, what is the probability that they

will have an affected child? Show the calculation and briefly explain your answer. (4 marks)

- END OF THE PAPER –

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