BTEC Applied Science – Unit 13: Microbiology

Mid-Year Examination

MCQ section: 50 questions (auto-marked)

Time remaining: 01:30:00

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SECTION A – MULTIPLE CHOICE QUESTIONS (50 questions)

Choose the best answer for each question. (1 mark each)

A1: Micro-organisms (Questions 1–12)

Diagram showing classification of microorganisms: bacteria, viruses, fungi, protozoa.

1. Which of the following is NOT considered a micro-organism?

a) Virus b) Bacterium c) Tapeworm d) Yeast

2. Which type of micro-organism is acellular and requires a host cell to replicate?

a) Bacteria b) Fungi c) Virus d) Protozoa

3. Which micro-organism is eukaryotic and has chitin in its cell wall?

a) Bacteria b) Fungi c) Virus d) Protozoa

4. Which of these is a single-celled prokaryotic organism?

a) Amoeba b) Streptococcus c) Candida d) Plasmodium

5. Which micro-organism causes malaria?

a) Bacterium b) Virus c) Fungus d) Protozoan

6. Which of these is an example of a beneficial micro-organism?

a) Lactobacillus in yogurt production b) Salmonella causing food poisoning c) Influenza virus d) Candida causing thrush

7. The study of viruses is called:

a) Bacteriology b) Mycology c) Virology d) Parasitology

8. Which micro-organism reproduces by forming spores?

a) Virus b) Some bacteria and fungi c) Protozoa only d) All microorganisms

9. Which of these is a multicellular fungus?

a) Yeast b) Penicillium mould c) Mushroom d) Both b and c

10. Pathogens are micro-organisms that:

a) Are always harmful b) Can cause disease c) Are always beneficial d) Cannot survive in the human body

11. Which of these is NOT a characteristic of bacteria?

a) Prokaryotic cells b) Peptidoglycan cell wall c) Membrane-bound organelles d) Reproduce by binary fission

12. Which micro-organism is used in the production of bread and beer?

a) Bacteria b) Virus c) Yeast (fungus) d) Protozoa

A2: Requirements for Growth (Questions 13–18)

Diagram showing requirements for microbial growth: nutrients, temperature, pH, oxygen, moisture.

13. Which temperature range is optimal for most pathogenic bacteria?

a) 0-10°C b) 15-25°C c) 37-40°C (body temperature) d) 60-80°C

14. Bacteria that require oxygen to grow are called:

a) Anaerobes b) Obligate aerobes c) Facultative anaerobes d) Microaerophiles

15. Which pH level do most bacteria prefer for optimal growth?

a) pH 2-3 (very acidic) b) pH 5-6 (slightly acidic) c) pH 6.5-7.5 (neutral to slightly alkaline) d) pH 9-10 (alkaline)

16. What is the purpose of the lag phase in bacterial growth?

a) Rapid cell division b) Cells adjust to new environment and synthesize enzymes c) Maximum population density is reached d) Cells begin to die

17. Which factor is NOT essential for microbial growth?

a) Nutrients b) Appropriate temperature c) Light d) Moisture

18. During which phase of bacterial growth is the population doubling at a constant rate?

a) Lag phase b) Log (exponential) phase c) Stationary phase d) Death phase

A3: Structure & Reproduction (Questions 19–26)

Diagram of bacterial cell showing structures: cell wall, cell membrane, cytoplasm, ribosomes, DNA, flagella.

19. The main method of reproduction in bacteria is:

a) Binary fission b) Budding c) Spore formation d) Sexual reproduction

20. Which bacterial structure is responsible for movement?

a) Pili b) Capsule c) Flagella d) Cell wall

21. The genetic material in bacteria is located in:

a) Nucleus b) Nucleoid region c) Mitochondria d) Ribosomes

22. Which structure provides protection and prevents phagocytosis in some bacteria?

a) Cell membrane b) Capsule c) Pili d) Flagella

23. What is the main component of bacterial cell walls?

a) Cellulose b) Chitin c) Peptidoglycan d) Protein

24. Viruses reproduce by:

a) Binary fission b) Taking over host cell machinery c) Budding d) Spore formation

25. Which structure allows bacteria to attach to surfaces?

a) Flagella b) Pili c) Capsule d) Cell membrane

26. Yeasts (a type of fungus) reproduce asexually by:

a) Binary fission b) Budding c) Spore formation d) Fragmentation

A4: Control Methods (Questions 27–30)

[Insert diagram comparing disinfectants, antiseptics, and antibiotics]

27. Which method completely destroys ALL microorganisms including spores?

a) Disinfection b) Sterilization c) Antisepsis d) Sanitization

28. Antibiotics are effective against:

a) Viruses b) Bacteria c) Fungi d) All microorganisms

29. Which of these is an example of an antiseptic?

a) Bleach used on work surfaces b) Iodine applied to skin before injection c) Autoclaving surgical instruments d) Antibiotic tablets

30. Hand washing with soap is effective because:

a) Soap kills all bacteria instantly b) Soap disrupts membranes and removes microorganisms mechanically c) Soap provides long-lasting protection d) Soap sterilizes the skin

B1: Epidemiology (Questions 31–35)

31. Epidemiology is the study of:

a) Individual cells b) The spread and control of diseases in populations c) Chemical reactions in the body d) Genetic inheritance

32. An epidemic refers to:

a) A disease that is always present in a population b) A sudden increase in cases of a disease in a specific area c) A worldwide spread of a disease d) A disease that affects only animals

33. A pandemic is:

a) A disease outbreak in a small community b) A worldwide spread of a disease c) A disease that is always present in a population d) A disease that spreads from animals to humans

34. The basic reproduction number (R0) indicates:

a) The mortality rate of a disease b) How many people one infected person will infect on average c) The incubation period of a disease d) The cost of treating a disease

35. Which is an example of a disease reservoir?

a) A contaminated water supply b) An infected person c) A mosquito carrying malaria d) All of the above

B2: Transmission Routes (Questions 36–40)

36. Which is an example of direct contact transmission?

a) Inhaling droplets from a sneeze b) Touching an infected person's skin c) Drinking contaminated water d) Being bitten by a mosquito

37. Airborne transmission involves:

a) Pathogens traveling on dust particles or droplets b) Direct physical contact between individuals c) Transfer via contaminated objects d) Transmission through blood

38. Which disease is typically transmitted via the fecal-oral route?

a) Influenza b) Tuberculosis c) Cholera d) HIV/AIDS

39. A vector is:

a) An inanimate object that carries pathogens b) A living organism that transmits pathogens c) A human carrier of disease d) A type of virus

40. Which is an example of vehicle transmission?

a) Sexual contact b) Blood transfusion c) Contaminated food or water d) Mosquito bite

B3: Normal Flora & the Body (Questions 41–43)

41. Normal flora refers to:

a) Pathogenic microorganisms b) Microorganisms that normally live on/in the body without causing harm c) Microorganisms used in vaccines d) Microorganisms found only in soil

42. Which is a benefit of normal flora?

a) They always cause disease b) They compete with pathogens for resources c) They weaken the immune system d) They have no function

43. Where in the body would you NOT expect to find normal flora?

a) Skin b) Large intestine b) Mouth d) Bloodstream of a healthy person

B4: Types of Infection (Questions 44–47)

44. An opportunistic infection occurs when:

a) A pathogen causes disease in a healthy individual b) Normal flora or environmental microorganisms cause disease in a compromised host c) A vaccine causes disease symptoms d) An infection spreads to multiple organs

45. A localized infection is:

a) Confined to one area of the body b) Spread throughout the body via bloodstream c) An infection that affects multiple systems d) Always fatal

46. Which term describes an infection acquired in a healthcare setting?

a) Community-acquired infection b) Nosocomial infection c) Zoonotic infection d) Opportunistic infection

47. A chronic infection:

a) Develops rapidly with severe symptoms b) Lasts for a long time, sometimes years c) Has no symptoms d) Is always fatal

B5: Immune System Basics (Questions 48–50)

48. The first line of defense against pathogens includes:

a) Skin and mucous membranes b) Antibodies c) White blood cells d) Fever

49. Phagocytes are white blood cells that:

a) Produce antibodies b) Engulf and destroy pathogens c) Release histamine d) Remember specific pathogens

50. Antibodies are produced by:

a) T-cells b) B-cells (plasma cells) c) Macrophages d) Red blood cells

SECTION B – SHORT ANSWER QUESTIONS (20 marks)

Answer all questions in the spaces provided. (2 marks each)

1. Describe two differences between bacteria and viruses.

2. List three factors that affect bacterial growth.

3. Explain the difference between disinfection and sterilization.

4. What is the difference between an epidemic and a pandemic?

5. Name two transmission routes for infectious diseases and give an example for each.

6. What are normal flora and give one benefit they provide to the human body.

7. Explain what is meant by an opportunistic infection.

8. Describe two ways the skin acts as a physical barrier against infection.

9. Why are viruses not affected by antibiotics?

10. What is hand hygiene and why is it important in healthcare settings?

SECTION C – ESSAY QUESTION (10 marks)

Answer the following question.

Discuss the importance of infection control measures in preventing the spread of healthcare-associated infections. Your answer should include:

Common transmission routes in healthcare settings
Key infection control measures (hand hygiene, PPE, sterilization)
The role of healthcare workers and patients in infection control
Consequences of poor infection control practices

SECTION D – CASE STUDY (10 marks)

[Insert diagram showing chain of infection with various transmission routes]

Scenario: "Outbreak in a Residential Care Home"

A residential care home for elderly residents reports an outbreak of gastrointestinal illness.
Over the past week, 12 residents and 4 staff members have developed symptoms including vomiting, diarrhoea, and abdominal cramps.
Investigation reveals:

Symptoms appear 12-48 hours after exposure
Residents share bathrooms and dining facilities
Some staff work while experiencing mild symptoms
Hand hygiene facilities are available but not always used
Cleaning routines have been inconsistent due to staff shortages
Lab tests confirm norovirus as the causative agent

Answer all parts:

1. Identify the most likely transmission route(s) in this outbreak. (2 marks)

2. Explain why elderly residents are particularly vulnerable to this infection. (2 marks)

3. Outline three specific infection control measures that should be implemented immediately. (3 marks)

4. Describe how this outbreak could have been prevented with proper infection control practices. (3 marks)

Only the MCQs (Section A) are auto-marked. Sections B, C, and D should be marked by the teacher.