The Cell and Its Components Flashcards
Describe the structure and function of the nucleus
- Stores and replicates the genetic information of the cell
- Is surrounded by a nuclear envelope which consists of 2 phospholipid bilayers to separate the nucleus from the rest of the cell
What is the importance of the nuclear envelope?
- Studded with thousands of nuclear pore complexes, which form openings in the envelope
- Allows ions, water, and other small particles though the openings
Describe the structure and function of the endoplasmic reticulum
- The surface is devoted to synthesizing proteins which are studded by ribosomes
- Molecular aggregates of protein and RNA
What is the function of the smooth ER?
- Synthesizes and metabolizes lipids and other lipid-containing molecules like phospholipids
- Can perform other functions, depending on the type of cell
Describe the structure and function of the vesicles
- Pieces off of the smooth ER which pinch off and form
-Used for transport and storage - A membrane-enclosed sac
Describe the structure and function of the Golgi apparatus
- A curved stack of membrane sacs
- Packages, processes, sorts, and distributes proteins, lipids, and other substances within the cell
Describe the structure and function of lysosomes
- A membrane-enclosed sac
- Contains enzymes that catalyze the hydrolysis of reactions by breaking down macromolecules
Describe the structure and function of peroxisomes
- A membrane-enclosed sac
- Contains an oxidative enzyme that breaks down excess fatty acids and hydrogen peroxide
- Can help produce bile and cholesterol
Describe the structure and function of the vacuole
- A large membrane-bound sac
- Only found in plants
- Stores amino acids, sugars, macromolecules, water, and ions
- Determines the turgor pressure of the plant depending on the plants water intake
Describe the structure and function of the mitochondria
Breaks down high-energy molecules to break them down to convert stored energy into usable energy
Describe the structure and function of chloroplast
- Contains photosynthetic pigment
- Absorbs light energy which converts carbon dioxide and water through redox reactions
- Stores glucose
Describe the structure and function of the cell wall
- Used for protection and support
- Only found in plant cells
- Around the outside of the cell
- Composed of polysaccharides, glycoproteins, or both
Describe the structure and function of the cytoskeleton
- A network of protein fibres which extends throughout the cytosol
- Provides the cell with structure, shape, support and mobility
What are the 3 structures in the endomembrane system?
- Vesicles
- Golgi Apparatus
- Lysosomes
What is the structure and function of cilia and flagella? How is their structure slightly different?
- A long, thin appendage which allows cells to move themselves or move substances over their surface
- Cilia: Small hair-like projections
- Flagella- Has a long, whip-like tail
What does the fluid mosaic model depict?
- A model of the basic framework of a semi-fluid phospholipid bilayer
- Represents the proteins and substances that are able to pass through
What are the important features of the fluid mosaic model?
- The mosaic section depicts proteins and other macromolecules
- The fluid section depicts the membranes in the molecule that can move freely
- Contains the phospholipid bilayer
Explain the structure and components of the phospholipid bilayer
- Composed of one glycerol and 2 fatty acids, and a highly polar phosphate group
Head: Polar, hydrophilic
Tail: Non-polar, hydrophobic - Held together by intermolecular interactions
- Polar heads face out, toward the aqueous environment
What are the 4 main factors that affect the fluidity of the phospholipid bilayer?
- Temperature
- % of Unsaturated Fatty Acids in Phospholipids
- Fatty Acid Tail Length
- Cholesterol in Membrane