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Topic 4.1: Cell biology

Subtopic 4.1.1: Cell structure

4.1.1.1 - Eukaryotes, Prokaryotes and Cell Scale

4.1.1.2a - Animal and Plant Cell Structures

4.1.1.2b - Microscopy of Plant and Animal Cells

4.1.1.3 - Cell Specialisation

4.1.1.4 - Cell Differentiation

4.1.1.5 - Microscopy, Magnification and Resolution

4.1.1.6a - Culturing Microorganisms and Bacterial Growth

4.1.1.6b - Aseptic Technique and Zones of Inhibition

Subtopic 4.1.2: Cell division

4.1.2.1 - Chromosomes, DNA and Genes

4.1.2.2 - Mitosis and the Cell Cycle

4.1.2.3 - Stem Cells

Subtopic 4.1.3: Transport in cells

4.1.3.1a - Diffusion and Factors Affecting Its Rate

4.1.3.1b - Surface Area to Volume Ratio and Exchange Surfaces

4.1.3.2a - Osmosis and Water Movement

4.1.3.2b - Required Practical - Osmosis in Plant Tissue

4.1.3.3 - Active Transport

Topic 4.2: Organisation

Subtopic 4.2.1: Principles of organisation

4.2.1 - Principles of Organisation

Subtopic 4.2.2: Animal tissues, organs and organ systems

4.2.2.1a - Digestive System, Enzymes and Digestion

4.2.2.1b - Required Practical - Food Tests

4.2.2.1c - Required Practical - Amylase and pH

4.2.2.2 - The Heart and Blood Vessels

4.2.2.3 - Blood

4.2.2.4 - Coronary Heart Disease and Treatments

4.2.2.5 - Health Issues and Disease Interactions

4.2.2.6 - Lifestyle Risk Factors and Non-Communicable Disease

4.2.2.7 - Cancer

Subtopic 4.2.3: Plant tissues, organs and systems

4.2.3.1 - Plant Tissues

4.2.3.2a - Plant Transport Organs And Transpiration

4.2.3.2b - Translocation and Plant Transport Data

Topic 4.3: Infection and response

Subtopic 4.3.1: Communicable diseases

4.3.1.1 - Communicable Diseases

4.3.1.2 - Viral Diseases

4.3.1.3 - Bacterial Diseases

4.3.1.4 - Fungal Diseases - Rose Black Spot

4.3.1.5 - Protist Diseases - Malaria

4.3.1.6 - Human Defence Systems

4.3.1.7 - Vaccination

4.3.1.8 - Antibiotics and Painkillers

4.3.1.9 - Discovery and Development of Drugs

Subtopic 4.3.2: Monoclonal antibodies

4.3.2.1 - Producing Monoclonal Antibodies

4.3.2.2 - Uses of Monoclonal Antibodies

Subtopic 4.3.3: Plant disease

4.3.3.1 - Detection And Identification Of Plant Diseases

4.3.3.2 - Plant Defence Responses

Topic 4.4: Bioenergetics

Subtopic 4.4.1: Photosynthesis

4.4.1.1 - Photosynthetic Reaction

4.4.1.2a - Rate of Photosynthesis and Limiting Factors

4.4.1.2b - Required Practical - Light Intensity and Photosynthesis

4.4.1.3 - Uses of Glucose from Photosynthesis

Subtopic 4.4.2: Respiration

4.4.2.1a - Aerobic and Anaerobic Respiration

4.4.2.1b - Anaerobic respiration in muscles and fermentation

4.4.2.2 - Response to Exercise

4.4.2.3 - Metabolism

Topic 4.5: Homeostasis and response

Subtopic 4.5.1: Homeostasis

4.5.1 - Homeostasis

Subtopic 4.5.2: The human nervous system

4.5.2.1a - The Nervous System and Reflex Arcs

4.5.2.1b - Required Practical - Reaction Time

4.5.2.2 - The Brain

4.5.2.3a - The Eye and Accommodation

4.5.2.3b - Vision Defects And Their Correction

4.5.2.4 - Control of Body Temperature

Subtopic 4.5.3: Hormonal coordination in humans

4.5.3.1 - Human Endocrine System

4.5.3.2a - Blood glucose control

4.5.3.2b - Diabetes and Blood Glucose Treatments

4.5.3.3a - Water, ions and urea balance

4.5.3.3b - Kidney Failure, Dialysis and Transplants

4.5.3.4 - Hormones in Human Reproduction

4.5.3.5 - Contraception

4.5.3.6 - Hormones to Treat Infertility

4.5.3.7 - Negative feedback

Subtopic 4.5.4: Plant hormones

4.5.4.1a - Plant Hormones and Tropisms

4.5.4.1b - Required Practical - Plant Responses

4.5.4.2 - Use of Plant Hormones

Topic 4.6: Inheritance, variation and evolution

Subtopic 4.6.1: Reproduction

4.6.1.1 - Sexual and Asexual Reproduction

4.6.1.2 - Meiosis

4.6.1.3 - Advantages and Disadvantages of Sexual and Asexual Reproduction

4.6.1.4 - DNA and the Genome

4.6.1.5 - DNA structure

4.6.1.6a - Genetic Inheritance Terms and Gametes

4.6.1.6b - Genetic crosses and Punnett squares

4.6.1.7a - Inherited Disorders

4.6.1.7b - Embryo Screening

4.6.1.8 - Sex Determination

Subtopic 4.6.2: Variation and evolution

4.6.2.1 - Variation

4.6.2.2 - Evolution

4.6.2.3 - Selective breeding

4.6.2.4a - Genetic Engineering Process

4.6.2.4b - Genetic Engineering Applications and Risks

4.6.2.5a - Plant Cloning by Cuttings and Tissue Culture

4.6.2.5b - Animal cloning and embryo transplants

Subtopic 4.6.3: The development of understanding of genetics and evolution

4.6.3.1 - Theory of evolution

4.6.3.2 - Speciation

4.6.3.3 - Development of Genetics

4.6.3.4 - Evidence for evolution

4.6.3.5 - Fossils

4.6.3.6 - Extinction

4.6.3.7 - Resistant Bacteria

Subtopic 4.6.4: Classification of living organisms

4.6.4 - Classification of living organisms

Topic 4.7: Ecology

Subtopic 4.7.1: Adaptations, interdependence and competition

4.7.1.1 - Communities and Interdependence

4.7.1.2 - Abiotic factors

4.7.1.3 - Biotic factors

4.7.1.4 - Adaptations

Subtopic 4.7.2: Organisation of an ecosystem

4.7.2.1a - Ecosystem Levels and Food Chains

4.7.2.1b - Required Practical - Sampling Populations

4.7.2.2 - Water and carbon cycles

4.7.2.3a - Decomposition and Decay Factors

4.7.2.3b - Investigating Decay Using Milk pH

4.7.2.4 - Impact of Environmental Change

Subtopic 4.7.3: Biodiversity and the effect of human interaction on ecosystems

4.7.3.1 - Biodiversity

4.7.3.2 - Waste Management

4.7.3.3 - Land Use

4.7.3.4 - Deforestation

4.7.3.5 - Global warming

4.7.3.6 - Maintaining biodiversity

Subtopic 4.7.4: Trophic levels in an ecosystem

4.7.4.1 - Trophic levels

4.7.4.2 - Pyramids of biomass

4.7.4.3 - Transfer of Biomass

Subtopic 4.7.5: Food production

4.7.5.1 - Factors affecting food security

4.7.5.2 - Farming Techniques

4.7.5.3 - Sustainable fisheries

4.7.5.4 - Role of Biotechnology

Topic 4.8: Key ideas

Synoptic connections across biology

4.8 - Key Ideas in Biology

4.3.1.4 - Fungal Diseases - Rose Black Spot

4.3.1.4 - Fungal Diseases - Rose Black Spot

Rose black spot is the fungal disease named in this part of AQA Biology. The exam focus is not a detailed fungal life cycle: it is the visible symptoms, how the disease reduces plant growth, how it spreads, and how it can be treated or controlled. A strong answer links each symptom or treatment to the biology behind it.

Rose black spot is fungal

Rose black spot is a fungal disease of rose plants. A fungus is a type of pathogen when it causes disease in a host organism. In this lesson, the host is a plant, not a human or animal.

Rose black spot

A fungal disease of rose plants in which purple or black spots develop on the leaves.

The specification only expects this named fungal disease here. Keep answers to rose black spot: symptoms, effect on growth, spread, and treatment.

Symptoms and reduced photosynthesis

The key symptom is purple or black spots developing on the leaves. Affected leaves often turn yellow and drop early. This matters because leaves are the main organs where photosynthesis happens.

When leaves are damaged, yellowed or lost early, the plant has less healthy leaf tissue for photosynthesis. Reduced photosynthesis means the plant makes less glucose for growth and other processes, so the growth of the plant is reduced.

[DIAGRAM: asset_name: rose-black-spot-disease-chain - diagram 1; asset_slug: 033_4_3_1_4_fungal_diseases_diagram1; file: diagram_assets/imagegen_regen_all/033_4_3_1_4_fungal_diseases_diagram1_imagegen.png; recommended_method: codex_image_gen; description: Monochrome flow diagram showing a rose leaf with purple/black spots, leaves yellowing and dropping early, reduced photosynthesis, reduced plant growth, spread by water or wind, and treatment by fungicides or removing and destroying affected leaves.]
Diagram

In an exam, "the plant looks unhealthy" is usually too vague. The creditworthy link is: black spots or yellowing affect leaves, leaves photosynthesise, less photosynthesis reduces growth.

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