📘 Chapter 1: The Science Of Biology– Solved Exercise Guide (Class 9)
Q1: What Are the Branches of Biology and Their Importance?
- Molecular Biology: Focuses on molecules like DNA and proteins.
➤ Significance: It helps us understand genetics and genetic disorders.
- Physiology: Deals with the functions of organs and systems.
➤ Significance: Plays a crucial role in medicine and health care.
- Palaeontology: The study of fossils and ancient life forms.
➤ Significance: Helps explain how life evolved on Earth.
- Pharmacology: Involves studying drugs and their effects on the body.
➤ Significance: Essential for developing new medicines.
🔍 Q2: Can You Differentiate These Biological Terms?
Anatomy vs. Morphology
➤ Anatomy: Study of internal body structures
➤ Morphology: Study of the external appearance
Cytology vs. Genetics
➤ Cytology: Study of cells
➤ Genetics: Study of heredity and genes
Biotechnology vs. Immunology
➤ Biotechnology: Use of living organisms in industries (like medicine, farming)
➤ Immunology: Study of immune system and disease resistance
Marine Biology vs. Ecology
➤ Marine Biology: Study of oceanic and sea life
➤ Ecology: Study of how organisms interact with their environment.
💪 Q3: How Does Biology Help Us Make Healthy Life Choices?
- Biology plays a major role in promoting a healthy lifestyle:
- Helps us understand the impact of hygiene, nutrition, and habits.
- Teaches how diseases spread and how to prevent them.
- Explains human body systems and how to take care of them.
👨🔬 Q4: Contributions of Great Scientists in Biology
- A.F.A. King: Suggested a link between mosquitoes and malaria.
- Ronald Ross: Proved that mosquitoes actually spread malaria.
- Charles Laveran: Discovered the malaria parasite in human blood.
🧪 Q5: Sorting Observations – Qualitative vs. Quantitative
Qualitative Observations
➤ Examples: Color of a cat, shape of leaves, desert climate, bird songs
Quantitative Observations
➤ Examples: Height of a giraffe, weight of a mango, bird body temperature, blood volume, tiger's speed
❓ Q6: Can a Hypothesis Be Wrong?
Absolutely! A hypothesis is a testable statement and can be disproven.
Example: "Vaccination reduces COVID-19 complications."
If vaccinated people have fewer complications, the hypothesis is correct.
If not, it may be disproven.
✅ Conclusion: Hypotheses need testing and evidence.
🦟 Q7: Why Is Malaria So Hard to Eradicate?
- Malaria remains a major global health issue because:
- Mosquitoes breed in tropical climates extensively.
- The malaria parasite hides in the liver – tough to eliminate.
🐛 Q8: Understanding the Role of Mosquitoes in Disease Spread?
- Mosquitoes are not just annoying – they are vectors. That means:
- They carry diseases (like malaria) without being affected themselves.
- The parasite they transmit is called Plasmodium.
- Ross’s famous experiment proved this connection between mosquitoes and malaria.
⚠️ Q9: Why Didn't Ross Let Infected Mosquitoes Bite Healthy People?
- Ronald Ross followed ethical science practices:
- It’s unsafe and unethical to deliberately infect healthy people.
- Could result in serious illness or even death.
- Good scientists prioritize safety and consent.
🧬 Q10: What’s the First Step in the Salivary Amylase Experiment?
In biology experiments, the right setup is key:
- First, choose a variable to test (like temperature).
- Keep all other factors constant.
- Then measure how salivary amylase breaks down starch.
🧫 Q11: Why Are Only Some People with Hepatitis B Actually Sick?
- Not everyone infected with a virus becomes visibly ill:
- Some are carriers – they have the virus but no symptoms.
- A strong immune system can fight off the symptoms.
- They can still spread the disease even if they appear healthy.
0 Comments