Biology Crash Course: Examination Preparation

Introduction

• This is a crash course for biology, aiming to cover 95% of the syllabus.
• Focus on three segments: Living Organisms in the Environment, Life Processes and Diseases, Continuity, and Variation.
• Emphasis on understanding and comfort over anxiety for exams.
• Additional resources and links will be provided for further study.

Graphs and Variables

• Graphs: Show relationships between variables.
  • Independent Variable: Placed on x-axis, manipulated by the experimenter.
  • Dependent Variable: Placed on y-axis, changes based on independent variable.
• Graph Drawing Tips:
  • Title, labeled axes, suitable scale.
  • Large enough to cover at least half a page.

Classification

• Organizing organisms based on features.
• Hierarchy: Kingdom, Phylum, Class, Order, Family, Genus, Species.
• Important to know examples and characteristics of each class.

Ecology and Ecological Studies

• Key Terms:
  • Niche: Role of organism in ecosystem.
  • Habitat: Where organism lives.
  • Population, Community, Ecosystem.
• Adaptations:
  • Marine, terrestrial, and other specific adaptations.
• Methods to Study Ecosystems:
  • Quadrats, line and belt transects, mark-release-recapture.

Abiotic vs. Biotic Factors

• Abiotic: Non-living, including water, air, soil.
• Biotic: Living organisms.
• Interaction: Food chain, food web, nutrient cycling.

Food Chains and Webs

• Energy Transfer: Decreases along the chain due to biological functions and heat loss.
• Bioaccumulation: Chemicals increase in concentration along the chain.
• Feeding Relationships: Predator-prey, decomposers.

Nutrient Cycles

• Carbon Cycle: Photosynthesis, respiration, decomposition, fossil fuels.
• Nitrogen Cycle: Nitrogen fixation, nitrification, denitrification.
• Water Cycle: Evaporation, condensation, precipitation.

Human Impact on Environment

• Biodegradable vs. Non-biodegradable waste.
• Issues: Overpopulation, overfishing, chemical fertilizers, pollution.
• Effects: Habitat loss, species extinction, human health impacts.

Cell Structures and Functions

• Key parts in plant and animal cells: cell wall, membrane, nucleus, mitochondria, chloroplasts.
• Differences between plant and animal cells.
• Specialized cells and their functions.

Transport in Cells

• Diffusion and Osmosis: Passive transport, no energy needed.
• Active Transport: Requires energy, against concentration gradient.
• Tonicity: Hypertonic, hypotonic, isotonic solutions.

Nutrition

• Types of Nutrition:
  • Autotrophic, heterotrophic, saprophytic, parasitic.
• Leaf Structure: External and internal structures, adaptations for photosynthesis.
• Photosynthesis: Equation, factors affecting rate.

Digestion

• Digestive System: Functions and structure of organs.
• Villi: Role in nutrient absorption.
• Nutrient Tests: For starch, proteins, fats, sugars.

Enzymes

• Biological catalysts made of proteins.
• Properties: Activation energy, substrate specificity, sensitivity to pH and temperature.

Respiratory System

• Structure and function: Nasal cavity, larynx, trachea, alveoli.
• Gas Exchange: Characteristics of alveoli for efficient exchange.
• Respiration Types: Aerobic vs. anaerobic.

Transport in Organisms

• Blood cells: Red blood cells (erythrocytes), white blood cells (leukocytes), platelets (thrombocytes).
• Blood vessels: Arteries, veins, capillaries.
• Heart structure and function.

Immunity

• Types of immunity: Natural, artificial.
• Role of leukocytes in defense mechanisms.

Excretion

• Removal of metabolic waste.
• Kidney Structure: Cortex, medulla, nephrons.

Skeleton System

• Bone and muscle function.
• Types of muscles, bone structure, joint mechanics.

Nervous System

• Central Nervous System: Brain, spinal cord.
• Types of neurons: Sensory, relay, motor.
• Reflex arc.

Sense Organs

• Function and structure of eye, ear, skin.

Reproduction

• Asexual vs. sexual reproduction.
• Menstrual cycle.
• Genetic inheritance: Punnett squares, sex-linked traits.

Genetic Variation

• Continuous vs. discontinuous variation.
• Factors affecting variation.

Conclusion

• Comprehensive review of key biology topics for examination preparation.
• Encouragement to utilize additional resources and links for further learning.