Chapter 4 Flashcards
Cells (22 cards)
What is a cell?
The smallest unit of life that can function on its own and can perform necessary life functions; reproduce itself.
What does Cell Theory state?
All living organisms are made of 1 or more cells.
What is the Endosymbiosis Theory?
Developed to explain the presence of two organelles in eukaryotes: Chloroplast and Mitochondrion.
What are characteristics of Prokaryotes?
- Single celled organisms
- Small cells
- Simple cells
- No organelles
- Circular DNA
- Examples: Bacteria, Archaea
What is the function of the Plasma Membrane in prokaryotic cells?
Takes in food and nutrients, gets rid of waste, builds and exports molecules, regulates heat exchange, regulates flow of materials in and out.
What does Cytoplasm refer to?
All the fluid within the cell.
What is the role of Ribosomes?
Help build proteins.
What does DNA carry in a cell?
Instructions on how to function, grow, and reproduce.
What is the function of the Cell Wall in prokaryotes?
Helps hold shape.
What is the function of Pili in prokaryotic cells?
Help move and stick to things.
What is the role of Flagellum?
Long structure that helps them move.
What are characteristics of Eukaryotes?
- Single or Multi-celled
- Larger cells
- More complex cells
- Nucleus and organelles present
- Linear DNA
- Examples: Plants, Animals, Fungi, Protists
What is the function of the nucleus?
The control center of the cell, storing genetic material (DNA) and coordinating activities like growth and reproduction.
The nucleus is essential for cell regulation and function.
What is the rough endoplasmic reticulum (RER) responsible for?
Helps in protein synthesis and transport.
RER is studded with ribosomes, which are the sites of protein synthesis.
What distinguishes the smooth endoplasmic reticulum (SER) from the rough endoplasmic reticulum (RER)?
Lacks ribosomes and is responsible for lipid synthesis, detoxification, and calcium storage.
SER plays a critical role in lipid metabolism.
What is the function of the Golgi apparatus?
Modifies, sorts, and packages proteins and lipids for transport within or outside the cell.
The Golgi apparatus is often referred to as the cell’s post office.
What do mitochondria do?
Generate ATP (energy) through cellular respiration.
Mitochondria are known as the powerhouse of the cell.
What role do lysosomes play in the cell?
Break down waste, old organelles, and harmful substances.
Lysosomes contain digestive enzymes for this purpose.
What is a cell wall?
Provides structural support and protection, found in plant cells and some prokaryotes.
The cell wall is primarily composed of cellulose in plants.
What is the function of chloroplasts?
Carry out photosynthesis, converting sunlight into energy.
Chloroplasts contain chlorophyll, which captures light energy.
What are vacuoles?
Storage compartments that hold water, nutrients, and waste; plant cells have a large central vacuole.
Vacuoles help maintain turgor pressure in plant cells.
What is the plasma membrane?
The cell’s boundary, controlling what enters and exits while maintaining homeostasis.
The plasma membrane is selectively permeable.
