8 topics with a brief review: definitions, key facts, and classroom questions.
In this section, we analyze the fundamental basis of life — cellular metabolism. You will learn how organisms acquire, store, and expend energy, as well as the fundamental differences in metabolic strategies between plant and animal cells.
The material covers all key nutritional types and energy metabolism processes. We will sequentially examine the light and dark reactions of photosynthesis, mechanisms of chemosynthesis, and the stages of energy metabolism: from anaerobic glycolysis and fermentation to highly efficient aerobic respiration.
Pay special attention to details: seminars and exams most frequently test the exact ATP yield at various stages of respiration, the precise localization of processes within organelles (mitochondria and chloroplasts), and reaction substrates. Without understanding these basic mechanisms, further successful study of biochemistry and normal physiology is impossible.
The primary property of living systems is the continuous exchange of matter and energy with the environment, characterizing organisms as open biological systems.
What does the cell sap of plant vacuoles contain?
It is an aqueous solution containing either reserve substances necessary for cellular activity or the end products of cellular metabolism.
What is the difference between photoautotrophs and chemoautotrophs?
Both types independently synthesize organic substances from inorganic precursors. The difference lies solely in the energy source: photoautotrophs require sunlight, while chemoautotrophs require energy from the chemical oxidation of inorganic substances (iron, hydrogen sulfide).
Where does the oxygen we breathe come from?
This is exclusively a byproduct of water photolysis taking place during the light-dependent phase. Water is split to donate its electrons to the reaction center of Photosystem II.
Do the dark reactions of photosynthesis occur at night?
Yes, the dark reactions can proceed both day and night, as light is not directly involved. The main requirement is the presence of accumulated ATP and NADPH₂ molecules in the chloroplasts.
What serves as the energy source in chemosynthesis?
The source of energy is the oxidation of inorganic compounds (e.g., ammonia, hydrogen sulfide, ferrous iron, or hydrogen). These are exothermic reactions, the energy of which is used to synthesize organic matter.
Master the entire topic in the "Biology" course
This is a summary. The course covers everything tested in classes and exams.
3,793 pages of study guides across all topics
Assignments and quizzes after every topic — just like in a colloquium