Lecture notes, concept summaries, and biology study guides from foundational to graduate-level topics.
C₃, C₄, and CAM Plants: Photosynthetic Strategies and Environmental Adaptation Land plants have evolved diverse photosynthetic strategies to survive in a wide range of climates. The three main pathways—C₃, C₄, and CAM—represent evolutionary solutions to the challenges…
Powerhouse of the Cell? A Deep Dive into the Multifunctional Mitochondrion We’ve all memorized it before: “The mitochondrion is the powerhouse of the cell.” It’s catchy. It’s concise. And it’s painfully outdated. In this article, we will unravel the…
Photosynthetic Pigments and Environmental Factors Affecting Photosynthesis The efficiency of photosynthesis is determined not only by the presence of photosynthetic pigments and environmental factors, but by how they interact to regulate light absorption and carbon fixation. Understanding this…
Cyclic vs. Noncyclic Photophosphorylation in Photosynthesis One of the most elegant regulatory features in photosynthesis is the switch between cyclic vs noncyclic photophosphorylation. These alternative electron flows within the thylakoid membrane allow the chloroplast to fine-tune its production…
Why Cell Cycle Regulation Is Essential The eukaryotic cell cycle must be tightly regulated to ensure that cells divide only when appropriate and that genomic integrity is maintained. Errors in cell cycle regulation can result in uncontrolled cell proliferation, genomic…
Introduction to microRNA microRNAs (miRNAs) are endogenous, non-coding RNA molecules approximately 21–23 nucleotides in length. They play a critical role in post-transcriptional regulation of gene expression in eukaryotic cells. Unlike messenger RNAs (mRNAs), miRNAs do not encode proteins but function…
Photosystems and the Electron Transport Chain in Photosynthesis The photosystems and electron transport chain form the foundation of light-dependent reactions in photosynthesis. Located in the thylakoid membrane of chloroplasts, these protein-pigment complexes work together to convert light energy into chemical…
The Biochemistry of the Calvin Cycle: Enzymes, Regulation, and Energy Balance The biochemistry of the calvin cycle lies at the heart of autotrophic life. Far beyond the simplified “dark reaction,” the Calvin cycle is a complex, tightly regulated biochemical process…
The Calvin Cycle: How Plants Turn CO₂ into Sugars through Photosynthesis The calvin cycle is the second major phase of photosynthesis. It takes place in the stroma of chloroplasts and does not require light directly. Instead, it uses the ATP…
The Light Reactions of Photosynthesis: How Plants Turn Sunlight into Energy The light reactions of photosynthesis are the first stage of the photosynthetic process, where plants capture sunlight and convert it into usable chemical energy. These reactions take place in…
