This unit focuses on the Bio-Logic of the atmosphere as a thermal regulator. You must understand the physical mechanism.....

Populations stay the same or diverge into new species. While D4.1 covered the.....

"Change over Time." Natural selection is the mechanism that explains how populations adapt.....

This unit focuses on the Bio-Logic of "Stability through Regulation." While C3.1 introduced the general concept of feedback.....

This unit moves from the molecular structure of DNA to the mathematical probability of traits. The Bio-Logic focuses on.....

"Gametogenesis and Gestation." This unit explores how complex multicellular organisms ensure the.....

We move beyond simple "high to low concentration" definitions of osmosis. The Bio-Logic here is based on energy—water potential.....

There is a heavy emphasis on Epigenetics (changes in gene expression that do not alter the DNA sequence itself). You are expected to.....

Mitosis is the mechanism for making exact copies (clones) for growth and repair, while Meiosis is.....

Mutations are no longer just "mistakes"; they are the ultimate source of all genetic variation. The Bio-Logic here focuses.....

this unit bridges the gap between the "blueprints" (DNA) and the "machinery" (Proteins). The Bio-Logic focuses on.....

The foundation of molecular genetics. The Bio-Logic focuses on "Fidelity and Continuity"—how an organism can copy three billion base pairs.....

This unit focuses on the "Bio-Logic" of thermodynamics—specifically, why energy can only be used once while matter can .....

this unit serves as the foundation for Ecology. The Bio-Logic moves from the individual organism to the complex.....

The immune system is framed as a multi-layered defense network. The Bio-Logic shifts from simple.....

The focus has shifted from looking at organs in isolation to understanding how they function as a unified team.....

The focus is on the Bio-Logic of electrical transduction—how a physical or chemical stimulus is converted into a moving wave.....

This unit explores how cells "talk" to each other across short and long distances. The focus has shifted from.....

Photosynthesis is presented as the primary energy-entry point for almost all life. The curriculum focuses on.....

Respiration is presented as the universal method of harvesting energy. The IBO has shifted the focus from merely memorizing the names.....

Enzymes and Metabolism is a cornerstone of the new IB Biology curriculum. In previous years, enzymes were often treated as isolated "scissors" or "glue." However.....

ecology has evolved from a study of "where things live" to a rigorous analysis of "how things interact." The central concept here is the Niche—not just a location.....

Evolution is not just a "history lesson." It is presented as a dynamic, ongoing process that explains the "Unity and Diversity".....

Movement is analyzed as an elegant coordination of Structural Proteins and Chemical Signals.....

Life for a large multicellular organism is a race against time; diffusion is too slow to move nutrients from your gut to your brain, so we evolved a pressurized "bulk flow" system......

The focus has shifted from simple anatomy to a deep understanding of the physical laws that govern how gases move.....

IB Biology Topic B2.3 Cell Specialization, Differentiation, Stem cells, Gene expression, Totipotent vs Pluripotent, Therapeutic uses of stem cells, IB Biology New Curriculum....

In the new 2025/2026 syllabus, the IBO has moved away from the "Label the parts of a cell" approach. Instead, the focus is now on "efficiency and evolution"....

The cell membrane is no longer just a "bag" holding the cell together; it is a dynamic, functional interface....

If DNA is the blueprint, proteins are the builders, the bricks, and the machinery.

Welcome back! As we shift into Theme B: Homeostasis and Metabolism, we encounter the molecular powerhouses of life: Carbohydrates and Lipids.

The IBO wants you to understand the Bio-Logic of loss—why species are disappearing at 100 to 1,000 times the background....

While earlier units focused on how traits change, this unit focuses on how one group of organisms splits....

Classification has moved from looking at "what an organism looks like" to "what its DNA says"....

This unit moves beyond simple naming. It asks a fundamental question: How do we draw lines around the...

Viruses are no longer just a footnote in the cell unit; they are explored as unique biological entities...

The focus has shifted from a simple "identify the parts" approach to a functional understanding of compartmentalization. The IBO wants you to understand...

This topic is not just a list of structures; it is the foundational "code" within the Theme: Unity and Diversity

This topic is not just a list of structures; it is the foundational "code" within the Theme: Unity and Diversity

Hello fellow biologists (and those just trying to survive the IB DP)! As we dive into the foundational topics of the IB Biology syllabus, it is easy to look at a molecule as simple as water and think, I got this