6 Questions
The movement of molecules from high to low concentration without energy input is called ______________ transport.
passive
The process of generating ATP using a proton gradient is called _______________.
chemiosmosis
The breakdown of organic molecules to generate energy is known as _______________.
catabolism
The specific binding site for a substrate on an enzyme is called the ______________ site.
active
The regulation of enzyme activity through the binding of effector molecules to a non-active site is called ______________ regulation.
allosteric
The substrate concentration at half-maximal velocity is represented by the symbol ______________.
Km
Study Notes
Cell Membrane Transport
-
Types of Transport:
- Passive Transport: movement of molecules from high to low concentration without energy input (diffusion, osmosis)
- Active Transport: movement of molecules against concentration gradient using energy (carrier proteins, pumps)
-
Transport Mechanisms:
- Simple Diffusion: molecules move through phospholipid bilayer
- Facilitated Diffusion: molecules move through transport proteins (carrier proteins, channels)
- Active Transport: energy-dependent transport using ATP or proton motive force
-
Proton Motive Force:
- Electrogenic transport: generates proton gradient across membrane
- Chemiosmosis: ATP synthesis using proton gradient
Metabolic Pathways
-
Catabolism:
- Breakdown of organic molecules to generate energy (ATP, NADH, FADH2)
- Examples: glycolysis, citric acid cycle, fatty acid oxidation
-
Anabolism:
- Synthesis of organic molecules using energy (ATP, NADH, FADH2)
- Examples: gluconeogenesis, fatty acid synthesis, amino acid synthesis
-
Energy Yield:
- ATP generated per glucose molecule: 36-38 ATP (aerobic respiration), 2 ATP (anaerobic respiration)
Enzyme
-
Enzyme Structure:
- Active site: specific binding site for substrate
- Apoenzyme: protein component
- Cofactor: non-protein component (coenzyme, metal ion)
-
Enzyme Kinetics:
- Substrate binding: formation of enzyme-substrate complex
- Enzyme-substrate complex: transition state, product formation
- Km (Michaelis constant): substrate concentration at half-maximal velocity
-
Regulation of Enzyme Activity:
- Allosteric regulation: binding of effector molecules to non-active site
- Feedback inhibition: product inhibits enzyme activity
- Post-translational modification: phosphorylation, ubiquitination
Test your knowledge of cell biology basics, including cell membrane transport, metabolic pathways, and enzyme structure and function. Learn about passive and active transport, catabolism and anabolism, and enzyme regulation.
Make Your Own Quizzes and Flashcards
Convert your notes into interactive study material.
Get started for free
