Cell Structure and Function

Study Notes

Semipermeable: allows certain substances to pass through while keeping others out
Phospholipid bilayer: composed of two layers of phospholipid molecules with hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails
Functions:
- Controls what enters and leaves the cell
- Provides structural support and maintains cell shape
- Regulates cell signaling and communication

Membrane-bound organelles:
- Have a distinct membrane separating them from the rest of the cell
- Examples: nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus
Non-membrane-bound organelles:
- Lack a distinct membrane
- Examples: ribosomes, cytoskeleton

Nucleus:
- Controls cell growth and division
- Contains genetic material (DNA)
Mitochondria:
- Generates energy for the cell through cellular respiration
- Converts glucose into ATP
Endoplasmic Reticulum (ER):
- Synthesizes and transports proteins and lipids
- Two types: rough ER (with ribosomes) and smooth ER (without ribosomes)
Golgi Apparatus:
- Modifies and packages proteins and lipids for transport
- Forms lysosomes and secretory vesicles
Ribosomes:
- Site of protein synthesis
- Found throughout the cytoplasm and attached to ER
Cytoskeleton:
- Provides structural support and shape to the cell
- Involved in cell movement and division

Cell membrane is semipermeable, allowing certain substances to pass through while keeping others out.
Phospholipid bilayer structure: two layers of phospholipid molecules with hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails.
Cell membrane functions: controls what enters and leaves the cell, provides structural support and maintains cell shape, and regulates cell signaling and communication.

Membrane-bound organelles: have a distinct membrane separating them from the rest of the cell.
Examples of membrane-bound organelles: nucleus, mitochondria, endoplasmic reticulum, Golgi apparatus.
Non-membrane-bound organelles: lack a distinct membrane.
Examples of non-membrane-bound organelles: ribosomes, cytoskeleton.

Nucleus functions: controls cell growth and division, contains genetic material (DNA).
Mitochondria functions: generates energy for the cell through cellular respiration, converts glucose into ATP.
Endoplasmic Reticulum (ER) functions: synthesizes and transports proteins and lipids, has two types: rough ER (with ribosomes) and smooth ER (without ribosomes).
Golgi Apparatus functions: modifies and packages proteins and lipids for transport, forms lysosomes and secretory vesicles.
Ribosomes functions: site of protein synthesis, found throughout the cytoplasm and attached to ER.
Cytoskeleton functions: provides structural support and shape to the cell, involved in cell movement and division.