GCSE Biology Paper

Overview

• Lauren, an expert examiner, covers AQA GCSE Biology Paper 1.
• Use timestamps and descriptions to navigate the video.
• Links to predicted papers and walkthroughs available.
• Website provides free questions and flashcards for exam preparation.

Cell Biology

Animal Cell Structure

• Parts of an Animal Cell:
  • Cell Membrane: Controls entry/exit of substances.
  • Cytoplasm: Site of chemical reactions.
  • Ribosomes: Protein synthesis.
  • Nucleus: Controls cell activities.
  • Mitochondria: Site of aerobic respiration.

Plant Cell Structure

• Differences from Animal Cells:
  • Cell Wall: Made of cellulose.
  • Permanent Vacuole: Supports structure.
  • Chloroplasts: Absorb light for photosynthesis.

Prokaryotic vs. Eukaryotic Cells

• Prokaryotic Cells:
  • No nucleus.
  • Example: Bacterial cells.
• Eukaryotic Cells:
  • Have a nucleus.
  • Examples: Animal and plant cells.

Specialized Cells

• Examples:
  • Plant: Root hair cells, xylem, phloem.
  • Animal: Sperm, nerve, and muscle cells.
• Differentiation:
  • Process by which cells become specialized.
  • Stem cells are undifferentiated.

Microscopy

• Light Microscopes:
  • Magnification: Image size divided by actual size.
  • Limitations: Can't see smaller than mitochondria.
• Electron Microscopes:
  • Higher magnification/resolution than light microscopes.

Culturing Microorganisms

• Bacterial Growth: Binary fission.
• Aseptic Techniques: To prevent contamination.
• Antibiotic Resistance: Measured by clear zones.

Genetics

DNA and Chromosomes

• DNA: Long molecule forming twisted double helix.
• Chromosomes: DNA coiled into solid structures.
• Mitosis:
  • Cell division producing identical daughter cells.

Stem Cells

• Types:
  • Embryonic: Differentiate into any cell type.
  • Adult: Limited differentiation.
  • Plant: Found in meristems.

Transport in Cells

Diffusion and Osmosis

• Diffusion: Movement from high to low concentration.
• Osmosis: Water movement through a semi-permeable membrane.

Active Transport

• Moves substances against concentration gradient using energy.

Organization and Digestion

Levels of Organization

• Cells, tissues, organs, organ systems, organisms.

Digestive System

• Enzymes:
  • Amylase: Carbohydrates.
  • Protease: Proteins.
  • Lipase: Lipids.
• Bile: Neutralizes stomach acid, emulsifies fats.

Circulatory System

Blood and Blood Vessels

• Arteries: Carry blood away.
• Veins: Carry blood to heart.
• Capillaries: Site of exchange.

Heart

• Function: Pumps blood around body.
• Processes: Double circulation.

Coronary Heart Disease

• Risk factors: Poor diet, lack of exercise.
• Treatments: Statins, stents, transplants.

Diseases

Non-Communicable Diseases

• Examples: Asthma, diabetes, heart disease.
• Risk factors: Genetics, lifestyle choices.

Cancer

• Types: Benign and malignant tumors.
• Risk factors: Smoking, UV exposure, obesity.

Plant Biology

Transpiration and Translocation

• Transpiration: Water movement from roots to leaves.
• Translocation: Sugar movement in phloem.
• Factors Affecting Rate: Light, temperature, humidity.

Photosynthesis

• Equation: Carbon dioxide + water -> glucose + oxygen.
• Factors: Light intensity, CO2 concentration, temperature.

Respiration

Aerobic vs. Anaerobic

• Aerobic: Requires oxygen, produces CO2 and water.
• Anaerobic: No oxygen, produces lactic acid (animals) or ethanol and CO2 (plants/yeast).

Immune System

Pathogens

• Types: Viruses, bacteria, fungi, protists.
• Transmission: Air, contact, vectors.

Vaccines and Antibiotics

• Vaccines: Trigger immune response.
• Antibiotics: Treat bacterial infections.

Drug Development

• Process: Preclinical and clinical trials.
• Testing: Toxicity, efficacy, dosage.

Monoclonal Antibodies

• Uses: Diagnostic tests, cancer treatments.
• Production: From cloned cells.

This summary encapsulates the essential content for students preparing for GCSE Biology Paper 1, providing a concise review of cell biology, genetics, human biology, plant biology, diseases, and applied biology concepts.