CIE IGCSE Biology Overview

Introduction

• An all-in-one CIE IGCSE Biology revision video.
• Focus on key concepts, exam wordings, and perfect answers.
• Mention of available revision guides and courses.

Characteristics of Living Organisms

• MRS GREN: Movement, Respiration, Sensitivity, Nutrition, Excretion, Reproduction, Growth.

Classification

• Importance of naming and classifying organisms using binomial naming system (genus and species).
• Species: Groups of organisms that can produce fertile offspring.
• Evolutionary similarities and modern classification using DNA sequences.

Dichotomous Keys

• Steps to identify organisms through dichotomous keys.

Five Kingdoms

• Plant, Animal, Protista, Bacteria, Fungi.
• Vertebrates and Invertebrates: Key features and classification.
  • Vertebrates: Mammals, Birds, Reptiles, Fish, Amphibians.
  • Invertebrates: Arthropods (Myriapods, Insects, Arachnids, Crustaceans).

Plants

• Differences between flowering plants (Angiosperms) and ferns.
• Structure and function of plant cells.

Viruses

• Simple structure: Protein coat surrounding genetic material.
• Always pathogenic.

Cells

• Bacterial cells: Unique features like cell wall, plasmids, and absence of nucleus.
• Viruses: Non-living entities.
• Protoctists: Diverse organisms like algae and amoebae.
• Fungi: Typical cell structure similar to plant cells.

Human Cell Structure

• Differences between plant and animal cells.

Specialized Cells

• Adaptations and functions of red blood cells, muscle cells, ciliated cells, nerve cells, sperm cells, and egg cells.
• Role of root hair cells, xylem, and phloem in plants.

Organization in Organisms

• Hierarchical structure from cells to organ systems.

Units and Measurement

• Conversion of scientific units.
• Examples of converting between different measurements.

Transport in Plants

• Xylem and Phloem: Structure and function.
• Absorption of minerals and water.

Transport in Animals

• Circulatory System: Heart structure and blood flow.
• Blood components: Red blood cells, platelets, plasma.
• Immune system: Phagocytes, lymphocytes, antibody production.

Human Digestive System

• Enzymes: Amylase, protease, lipase.
• Digestion processes: Mechanical and chemical.
• Teeth structures and functions.

Photosynthesis

• Process, importance, and limiting factors (light, CO2, temperature).

Respiration

• Aerobic vs. anaerobic respiration.

Excretion

• Human excretory system: Kidneys, urethra.

Nervous System

• Components: Central nervous system, synapses, reflex actions.
• Details of the eye structure and its functions.

Hormones

• Role of adrenaline, insulin, and other hormones.
• Blood glucose regulation.

Ecology

• Definitions: Habitat, population, community, producer, consumer.
• Food webs and pyramids of numbers and biomass.
• Environmental impact and conservation.

Genetics

• DNA structure, genes, alleles.
• Genetic crosses: Punnett squares, genotype vs. phenotype.
• Inheritance patterns, sex linkage.

Evolution and Natural Selection

• Charles Darwin’s theory, adaptation, mutation.
• Selective breeding and its application.

Human Impact on Environment

• Pollution: Eutrophication, plastics.
• Greenhouse effect and global warming.
• Conservation efforts and sustainable development.

Biotechnology

• Genetic engineering: Insulin production, GM crops.
• Fermentation processes in food production.

Conclusion

• Encouragement to use resources and continue studying for success in biology exams.