Life Sciences 2 - Exam - Long Answer Questions Flashcards
What is antimicrobial resistance and how does it happen? What are four factors contributing to antimicrobial resistance?
Antimicrobial resistance (AMR) occurs when bacteria, parasites, viruses or fungi change to protect themselves from the effects of antimicrobial drugs designed to destroy them.
This means previously effective antimicrobial drugs used to treat or prevent infections may no longer work.
Four factors contributing to antimicrobial resistance:
1. Prolonged hospitalisations
- Use of outdated medications
- The delivery of more complex health care which may require longer use of antibiotics.
- Overuse of antibiotics in livestock.
Define the terms Mortality, Morbidity, Burden of Disease, Incidence and Prevalence.
Burden of Disease: The impact of a health problem, measured by financial cost, mortality, morbidity, and other indicators.
Mortality: The rate of death within a population.
Morbidity: The presence of illness or disease in a population.
Incidence: The number or rate of new cases of a particular condition during a specific time.
Prevalence: The total number of cases of a disease in a given population at a specific time.
What are mRNA vaccines? How do they work?
mRNA vaccines carry genetic material that teaches our cells how to make a harmless piece of “spike protein,” which is found on the surface of a virus. Cells display this piece of spike protein on their surface, and an immune response is triggered inside our bodies. This produces antibodies to protect us from getting infected if the virus enters our bodies.
Describe the differences between mechanical and chemical digestion, focusing on carbohydrates, proteins or lipids and include the enzymes involved.
Mechanical Digestion: Physical breakdown of food (e.g., chewing, stomach churning).
Chemical Digestion: Enzymes break down macromolecules (e.g., amylase for carbohydrates, pepsin for proteins, lipase for fats).
Enzymes Involved: Amylase (carbohydrates), protease (proteins), lipase (lipids) each target specific bonds within these macromolecules.
What are the different types of vaccines and what do they do?
Live attenuated: These use a weakened form of a live pathogen that can still replicate, but doesn’t cause disease. They produce a strong immune response. Require 1 – 2 doses. Examples: rotavirus, varicella.
Inactivated: Contain pathogens killed by heat, chemicals, or radiation. They cannot replicate, so the immune response is weaker, often requiring boosters.
Examples: Hepatitis A, rabies.
Subunit: Contain killed, antigenic component of pathogen, such as surface proteins, to trigger an immune response without live components, making them safer.
Examples: Pneumococcal, HPV.
Toxoid: Contain inactivated toxins made by pathogen. The immune system learns to neutralise the real toxin if exposed later. It may require booster shots.
Examples: Diphtheria, tetanus.
Discuss AMR, including causes, implications for human health and strategies for prevention.
Definition: AMR occurs when microorganisms (bacteria, viruses, fungi, and parasites) evolve to resist the effects of drugs, making infections harder to treat.
Causes: Overuse and misuse of antibiotics, lack of new antimicrobial development, and inadequate infection control.
Implications: Increased healthcare costs, prolonged hospital stays, and higher mortality.
Prevention: Responsible antibiotic use, improved infection control practices, and investment in research for new treatments.
What are the 6 functions of proteins?
Defense: Globular proteins called
immunoglobulins (antibodies) seek
out objects considered non-self
Transport: Cell membrane, a barrier separating
internal contents from surroundings
Support: Cytoskeleton
Motion: Myosin and actin protein arrange to form muscle fibers
for motion
Regulations: Protein hormones
Storage: ion binding proteins like Ferritin that store ion.
List the properties of each carbohydrates, lipids, proteins, nucleic acids
Carbohydrates serve as a primary source of energy.
Monomers: Monosaccharides joined by glycosidic bond
Examples: Starch, cellulose
Elements: C,H,O
Functions: Energy source, structural component, Reserve food
Lipids serve as a secondary source of energy.
Monomers: Fatty acids and glycerol joined by ester bond
Examples: Fats, oils, waxes
Elements: C,H,O
Functions: Energy source, Insulation, membrane components, hormone
Proteins are structural and functional units of human body which are of prime importance and survival of human beings.
Monomers: Amino acids joined by peptide bond
Examples: Insulin, Collagen
Elements: C,H,O, N, S
Functions: Enzyme, structure movement, defence hormones
Nucleic acids are polymer responsible for the reproduction of genetic materials and proteins.
Monomers: Nucleotides joined by phosphodiester bond
Examples: DNA, RNA
Elements: C,H,O, N, P
Functions: Stores genetic information
Explain the role of digestive organs in carbohydrate metabolism.
*Mouth: Begins carbohydrate digestion with salivary amylase.
Stomach: No significant carbohydrate digestion due to the acidic environment, which inhibits amylase activity.
*Small Intestine: Main site of carbohydrate digestion and absorption, where pancreatic amylase and brush border enzymes act.
*Pancreas: Secretes pancreatic amylase into the small intestine.
*Liver: Processes absorbed monosaccharides and helps regulate blood glucose levels.
What properties of lipids make their digestion more complicated that that of carbohydrates and proteins? How are lipids made accessible for digestion?
Unlike proteins and carbohydrates, neither lipids or its products are water soluble. The lipids are converted into mixtures of lipid droplets and water (emulsions), a conversion enhanced by bile salts. The emulsions are accessible to lipases. The fatty acids generated by lipase are carried in micelles to the intestinal membrane.
