🦠 • Lesson 1.5 : Diseases, Immunity & Respiration (Bio) Flashcards
After this lesson, you will be able to describe pathogens, transmissions, vaccinations, as well as gas exchange in humans, and the types of respiration. (34 cards)
What is a pathogen?
A pathogen is a disease-causing organism.
Describe a transmissible disease
A transmissible disease is a disease in which the pathogen can be passed from one host to another.
How can a pathogen be transmitted?
By direct contact, including through blood and other body fluids (ex. cough, sneeze).
Or Indirectly, including from contaminated surfaces, food, animals and air.
How does the skin defend against pathogens?
The skin acts as a barrier, preventing pathogens from entering the body.
How do hairs in the nose defend against pathogens?
Nose hairs trap dust and microbes, stopping them from entering the respiratory system.
How does mucus defend against pathogens?
Mucus traps bacteria and dust in the airways, preventing them from reaching the lungs.
How does stomach acid defend against pathogens?
Stomach acid kills most bacteria and viruses in food before they can cause harm.
How do white blood cells defend against pathogens?
White blood cells engulf pathogens (phagocytosis) and produce antibodies to destroy them.
Why is a clean water supply important in controlling disease?
Prevents the spread of waterborne diseases like cholera by removing harmful pathogens.
What factors help to prevent diseases?
Clean water supply,
Hygienic food preparation,
Good personal hygiene,
Proper waste disposal,
Sewage treatment.
What are the key features of viruses?
A Protein coat and Genetic material.
What is active immunity?
The body produces its own antibodies to fight a pathogen
Why do antibodies only work on specific pathogens?
Each pathogen has unique antigens with specific shapes, and antibodies have complementary shapes that fit these antigens.
What do antibodies do?
Antibodies bind to antigens or destroy pathogens directly—or mark them for phagocytes.
How does the body develop active immunity?
After an infection, or through vaccination.
What is introduced into the body during vaccination?
Weakened pathogens or their antigens.
How does the body respond to a vaccine?
Lymphocytes recognize the antigens and produce antibodies.
How does vaccination provide long-term immunity?
Memory cells are created, allowing the body to respond faster if exposed to the same pathogen again.
What is the correct order of structures in the respiratory system?
- Larynx → 2. Trachea → 3. Bronchi → 4. Bronchioles → 5. Alveoli & Capillaries → 6. Lungs → 7. Diaphragm → 8. Ribs → 9. Intercostal Muscles
How can we test for carbon dioxide in human breath?
Limewater test – Limewater turns cloudy when we breathe out, proving expired air has more CO₂ than inspired air.
What are the differences between inspired and expired air in humans?
Inspired Air: More oxygen, less carbon dioxide, less water vapor.
Expired Air: Less oxygen, more carbon dioxide, more water vapor.
How does physical activity affect breathing rate and depth?
Increased CO₂ in the blood is detected by the brain, which causes the rate and depth of breathing to increase to expel more CO₂ and bring in more oxygen.
Why is a large surface area important for gas exchange?
A large surface area allows more oxygen and carbon dioxide to be exchanged at once, increasing the efficiency of gas exchange.
What are some uses of energy in living organisms?
Energy is used for:
* Muscle contraction
* Protein synthesis
* Cell division
* Growth
* Passage of nerve impulses
* Maintenance of a constant body temperature
