Biology Yr 9 Flashcards
(25 cards)
What are communicable diseases?
Infectious diseases that can spread from person to person (or animal to person)
Caused by pathogens such as bacteria, viruses, fungi, and protists.
What are the types of pathogens that cause communicable diseases?
- Bacteria (e.g., Salmonella, TB)
- Viruses (e.g., Flu, COVID-19)
- Fungi (e.g., Athlete’s foot)
- Protists (e.g., Malaria)
How do communicable diseases spread?
- Direct contact (touching, kissing)
- Air (coughs, sneezes – droplets)
- Water (drinking contaminated water)
- Vectors (insects like mosquitoes spreading malaria)
What is an example of a disease caused by a virus?
Measles
Spreads through airborne droplets and can be prevented by vaccination.
What is a method to prevent the spread of malaria?
Using nets and insect repellent
Malaria is caused by a protist and spreads through mosquito bites.
What is the role of antibiotics?
Kill bacteria (not viruses)
Example: Penicillin, discovered by Alexander Fleming.
What happens during antibiotic resistance?
Bacteria mutate and antibiotics stop working (e.g., MRSA).
What do painkillers do?
Reduce symptoms (e.g., pain, fever) but don’t kill pathogens.
What are the key aspects tested during drug development?
- Toxicity (is it safe?)
- Efficacy (does it work?)
- Dosage (what amount is safe?)
What constitutes a biological community?
All the populations of different species living together in a habitat.
What is the definition of a habitat?
The place where organisms live.
What is an ecosystem?
All the living things (community) and the non-living environment in an area.
What is the relationship between an ecosystem and a community?
Ecosystem = Community + environment.
What is a producer in an ecosystem?
An organism that makes its own food (plants).
Fill in the blank: A _______ is an organism that eats other organisms.
Consumer
What is biodiversity?
The variety of living organisms in an ecosystem.
Why is biodiversity important?
- Stable ecosystems
- Food, medicine, raw materials
- Resilience to change
What are some threats to biodiversity?
- Deforestation
- Pollution
- Climate change
- Hunting/poaching
- Invasive species
What is a method to protect biodiversity?
- Breeding programs
- Protected areas (nature reserves)
- Laws against deforestation/hunting
- Education
What are the effects of pollution?
- Air pollution (e.g., sulfur dioxide → acid rain)
- Water pollution (e.g., chemicals → kills aquatic life)
- Land pollution (e.g., pesticides, plastics)
What does waste management involve?
- Reduce, reuse, recycle
- Compost organic waste
- Treat sewage and industrial waste
- Reduce plastic use
What human activities contribute to land use?
- Farming (agriculture)
- Building (housing, roads)
- Forestry (cutting down trees)
- Quarrying (mining)
What are the effects of deforestation?
- Loss of habitats
- Less oxygen (fewer trees = less photosynthesis)
- More CO₂ in the air (trees absorb CO₂)
- Soil erosion
What are some causes of environmental change?
- Climate change (global warming)
- Deforestation
- Pollution
- Urbanisation
