OVERMUGGED 2024 S3 IP NYGH Biology WA2 Revision - Worksheet

REVISION WA2 SEC 3 & SEC 4 KOVAN | BUKIT TIMAH | MARINE PARADE 87702540 OVERMUGGED@GMAIL.COM WWW.OVERMUGGED.COM FOLLOW US ON IG:

© OVERMUGGED | www.overmugged.com | 2024 1 UPPER SECONDARY IP BIOLOGY Infectious Diseases in Humans NYGH S3 WA2 Revision Name: Date: What are pathogens? Pathogen Acellular Virus Prion Cellular Prokaryotic Bacteria Eukaryotic Fungi Protozoa Helminth Algae

© OVERMUGGED | www.overmugged.com | 2024 2 Prion diseases All cell membranes have proteins embedded within for a variety of functions. Prions form when proteins in the brain misfold or mutate into different structures and conformations. These abnormal proteins cause prion diseases (also known as transmissible spongiform encephalopathy, TSE) that are transmissible and unfortunately, untreatable. Some studies have hypothesised that these abnormal proteins may bind to and induce other proteins to also undergo a conformational change. This could result in a chain reaction that propagates the growth of prions and accelerates the progression of the diseases it causes. Prion diseases are rare , affecting approximately 0.0002% of the global population yearly, and are either inherited or acquired . However, prion diseases may even occur without inheriting a genetic muation or exposure to prion infections. Prion disease Characteristics Creutzfeldt-Jakob Disease (CJD) Severe, rapid onset, fatal Cognitive impairment Muscle atrophy Personality changes Kuru Non-immunogenic Arose from ritualistic consumption of tissues from recently deceased family members (including the brain) Loss of bodily control Behavioural changes Random compulsive laughing or crying Bovine Spongiform Encephalopathy (BSE) “Mad Cow disease” Abnormal posture Coordination problems and difficulty in rising Decreased milk production Mad Cow disease: https://youtu.be/Pxojz6grwcU

© OVERMUGGED | www.overmugged.com | 2024 3 Pathogens Pathogen Characteristics Parasitic worm/helminth Worm-like parasite Invertebrates with elongated, flat, or round bodies Complex life cycle involving hosts Helminths: Intestinal Nematodes: https://youtu.be/O1qf3R3zMB0 Colonoscopy Demonstrating a Moving Worm | NEJM: https://youtu.be/AZr36qP14p4 Protozoa Unicellular eukaryotes Individual organisms or parasitic Motile via use of flagella, pseudopodia, or cilia Fungi Eukaryotic Unicellular (yeast) and multicellular (mushrooms, molds) Absorb nutrients from immediate surrounding Prokaryote Cells without endomembrane systems Short generational times result in overwhelming infection rates Adapt to host immune system defenses quickly Anthrax: https://youtu.be/vVD5QtVmC8s Virus Smallest (20 – 400 nm) Single or double-stranded nucleic acids surrounded by a protein coat Requires a host to reproduce using host cell machinery Specific to target cells Prion Mutated cell protein with abnormal structure Cause neurodegenrative diseases No cure

© OVERMUGGED | www.overmugged.com | 2024 6 What’s this disease? You’re an aspiring epidemiologist tasked with caterogising some diseases. Do some research to identify a disease caused by each pathogen type discussed today. Also include the scientific name of the causative agent, the mode of transmission, and how it affects the host. Consolidate your findings in the table below. Pathogen Disease Scientific name of pathogen Mode of transmission How it affects the host Parasitic worm/helminth Protozoa Fungi

© OVERMUGGED | www.overmugged.com | 2024 6 Pathogen Disease Scientific name of pathogen Mode of transmission How it affects the host Prokaryote Virus Prion Share your findings with your colleagues. Let’s hope to uncover as many different diseases together as possible! The Deadliest Virus on Earth: https://youtu.be/4u5I8GYB79Y The Most Horrible Parasite: Brain Eating Amoeba: https://youtu.be/7OPg-ksxZ4Y The Most Gruesome Parasites – Neglected Tropical Diseases – NTDs https://youtu.be/qNWWrDBRBqk

© OVERMUGGED | www.overmugged.com | 2024 6 Write your answers in the table below. 1 2 3 4 5 6 7 8 9 10 Question 1 Which of the following is not an infectious disease? (A) COVID-19 (B) AIDS (C) Dengue fever (D) Diabetes Question 2 What can viruses also be classified under? (A) A pathogen (B) A fungus (C) A bacterium (D) A protist Question 3 Which of the following diseases is transmitted by bacteria? (A) Influenza (B) HIV (C) Tuberculosis (D) Kuru

© OVERMUGGED | www.overmugged.com | 2024 6 Question 4 Which of the following is not a symptom of pneumococcal disease? (A) High fever (B) Chest pain (C) Stiff neck (D) Swollen eyes Question 5 Sally was sadly down with a viral infection. Her mother tried the following treatments on her. I. A week’s dose of antibiotics II. Taking off-the-shelf medication for sore throat III. Resting in bed more IV. Having Sally take a cold shower Which treatment(s) helped Sally recover faster? (A) I and II only (B) II and III only (C) I and III only (D) I, III, and IV Question 6 George suggested four possible ways to make vaccines using viruses. I. Live and attenuated II. Original virus III. Inactivated IV. Partial structure of the original virus Which option would result in an unsafe vaccine? (A) I and II (B) II only (C) II and IV (D) III and IV

© OVERMUGGED | www.overmugged.com | 2024 6 Question 7 Which vaccine type would confer the longest lasting immunity to a disease? (A) Live and attenuated (B) Original virus (C) Inactivated (D) Partial structure of the original virus Question 8 The graphs below show how the antibody concentration may change following a vaccination. Which graph correctly explains why some vaccines require multiple doses? (A) Graphs A and B (B) Graph A only (C) Graphs B and C (D) Graph C only

© OVERMUGGED | www.overmugged.com | 2024 6 Question 9 What should people do to combat antibiotic resistance? (A) Only share antibiotics within the immediate family (B) Use leftover antibiotics for future illnesses to save costs (C) Only take antibiotics when prescribed and complete the stated course (D) Take double the dosage to kill the bacteria more effectively Question 10 After an all-night study party, Andy fell really sick and was hospitalised with a new type of disease. To establish the way in which the pathogen was spread, Andy described to the doctor some of the events that he recalled from the party. I. He shook the hand of an old friend who he had not seen in years. II. He was standing close to someone who was constantly coughing. III. He drank a beverage from an unknown cup that was on the table. IV. He ate a piece of chilli chocolate candy that was individually wrapped. Which event(s) could have led to Andy being infected by another person? (A) I and III only (B) II and IV only (C) I, III, and IV (D) I, II, and III