What is the basic unit of structure and function in living organisms?
Cell
The cell is the smallest unit of living material that can carry out all activities necessary for life.
Name the two types of cells.
- Eukaryotic cells
- Prokaryotic cells
Eukaryotic cells contain a membrane-bound nucleus and organelles, while prokaryotic cells lack a nucleus and membrane-bound organelles.
What is the nucleoid in prokaryotic cells?
Region where the circular DNA lies free
This is a key feature distinguishing prokaryotic cells from eukaryotic cells.
What is the cell wall in prokaryotic cells made of?
Peptidoglycan
This structure provides support and protection to prokaryotic cells.
What are the primary functions of the following organelles in eukaryotic cells?
- Nucleus
- Ribosomes
- Golgi apparatus
- Stores DNA, directs cell activities, site of ribosome assembly
- Protein synthesis
- Modifies, packages, and sorts proteins into vesicles
Each organelle has a specific role in maintaining cell function.
What is the function of the mitochondria?
Produces ATP via cellular respiration
Mitochondria are known as the powerhouse of the cell.
What is the role of the cytoskeleton?
Maintains cell shape and facilitates movement
It is composed of protein fibers.
What are the main differences between plant cells and animal cells?
- Plant cells have a cell wall and chloroplasts
- Animal cells have centrioles and more lysosomes
These differences affect their structure and function.
What does ATP stand for?
Adenosine Triphosphate
ATP is the energy currency of the cell.
What are the two main sources of ATP?
- Photosynthesis
- Cellular respiration
These processes convert energy into a usable form for cells.
What are the two stages of photosynthesis?
- Light-dependent reactions
- Light-independent (Calvin) reactions
These stages are essential for synthesizing carbohydrates.
What is the difference between aerobic and anaerobic respiration?
- Aerobic respiration requires O₂
- Anaerobic respiration occurs when O₂ is scarce
Anaerobic respiration can lead to lactic acid production in muscle cells.
What is the structure of DNA?
Double helix formed by two complementary strands
DNA is organized into chromosomes wrapped around histone proteins.
What is the central dogma of molecular biology?
DNA → transcription → RNA → translation → proteins
This process describes how genetic information is expressed.
What are the main differences between DNA and RNA?
- DNA: Double-stranded, deoxyribose, A, G, C, T
- RNA: Single-stranded, ribose, A, G, C, U
These differences affect their functions in the cell.
