OCR A-Level Biology Module 2 Quiz

Module 2: Key Concepts

• OCR A-Level Biology Module 2 covers eukaryotes and prokaryotes, cell signaling, and genetics across organisms.
• The module emphasizes how biological processes are interconnected and adapt to environments.
• Gene expression control, mitosis, meiosis, and genetics are key cellular-level topics.
• Organisms' interactions with their environment is repeatedly examined through examples and case studies.

Eukaryotic Cell Structure

• Eukaryotic cells have membrane-bound organelles (nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles).
• Each organelle has a specific role in cellular functions (energy production, protein synthesis, waste disposal).
• The cytoskeleton shapes the cell and enables internal transport.

Prokaryotic Cell Structure

• Prokaryotic cells are simpler, lacking membrane-bound organelles.
• Key features include a cell wall (often peptidoglycan), capsule (protective outer layer), plasma membrane, ribosomes, and a single circular chromosome.

Cell Signaling

• Cell signaling enables communication between cells for coordinated responses to internal and external triggers.
• Signaling pathways are cascades, starting with a signal molecule and resulting in a cellular response.
• Signaling pathways are various depending on the distance the signal travels (paracrine, endocrine, etc.).

Cellular Respiration

• Cellular respiration breaks down organic molecules to produce ATP (energy).
• Glycolysis, Krebs cycle, and electron transport chain form this process.
• Anaerobic and aerobic respiration yields different ATP amounts.

Photosynthesis

• Photosynthetic organisms use light to turn carbon dioxide and water into glucose and oxygen.
• Photosynthesis takes place in chloroplasts, with light-dependent and light-independent reactions.

Mitosis and Meiosis

• Mitosis produces genetically identical daughter cells from a parent cell, essential for growth, repair, and asexual reproduction.
• Meiosis forms four haploid gametes from a single diploid cell, vital for sexual reproduction.

Gene Expression and Regulation

• Gene expression uses gene information to create proteins.
• Gene expression regulation controls when and how genes are expressed (critical for development, differentiation, and environmental responses).
• Transcription factors and epigenetic modifications affect gene expression.

Genetics in Relation to Organisms

• Mendelian genetics, inheritance patterns, and probability are studied.
• Population genetics examines genetic variation within populations.
• Molecular genetics explores DNA replication, transcription, and translation.

Case Studies

• Case studies demonstrate biological concepts and practical applications across organisms and their environmental interactions.