Top 25 Topics to revise for your IGCSE Biology Exam in 2024 (part 1)

Summary

This video covers the top 20 frequently asked topics in IGCSE Biology, focusing on key concepts such as the absorption of ions by active transport, factors affecting enzyme activity, and the limiting factors of photosynthesis. It highlights important aspects of plant nutrition, coronary heart disease, the differences between passive and active immunity, and the mechanics of breathing. Additionally, the video discusses oxygen debt and lactic acid removal, along with the structure and function of nephrons in filtration and reabsorption, providing a comprehensive overview for students preparing for their exams.

Takeaways

• 📚 Study the absorption of ions by active transport.
• 🌡️ Investigate the effect of temperature and pH on enzyme activity.
• 🌱 Understand the limiting factors of photosynthesis.
• ⚗️ Explore the impact of magnesium and nitrates on plant growth.
• 🔬 Learn about nutrient absorption through visking tubes.
• ❤️ Examine key factors and events associated with coronary heart disease.
• 🛡️ Study the differences between passive and active immunity.
• 💨 Learn the mechanism of breathing in and out.
• 🏃‍♂️ Understand the events leading to oxygen debt and lactic acid removal in the body.
• 🏥 Examine the structure of the nephron and the processes of filtration and reabsorption.

Q & A

What is the first topic covered in IGCSE biology?

The first topic is the absorption of ions by active transport.

How do temperature and pH affect enzyme activity?

Enzyme activity is influenced by both temperature and pH, as each enzyme has an optimal range for these conditions.

What are limiting factors in photosynthesis?

Limiting factors of photosynthesis include light intensity, carbon dioxide concentration, and temperature.

What role do magnesium and nitrates play in plants?

Magnesium is crucial for chlorophyll production, while nitrates are essential for protein synthesis in plants.

What is the purpose of investigating the absorption of nutrients through Visking tubes?

Investigating nutrient absorption through Visking tubes helps demonstrate how substances move through semi-permeable membranes.

What are key factors associated with coronary heart disease?

Key factors include high blood pressure, high cholesterol, smoking, obesity, and lack of physical activity.

What is the difference between passive and active immunity?

Passive immunity is acquired through antibodies from another source, while active immunity is developed through exposure to pathogens.

What mechanisms are involved in breathing?

Breathing involves inhalation (drawing air into the lungs) and exhalation (expelling air), regulated by diaphragm and intercostal muscles.

What happens during oxygen debt and lactic acid removal?

During oxygen debt, the body uses anaerobic respiration, producing lactic acid, which is later converted back to glucose when oxygen is available.

What is the structure and function of the nephron?

The nephron is the functional unit of the kidney, involved in filtration and reabsorption of water and solutes from blood.