Cell Biology Chapter 1: Cell Structure

Study Notes

Plasma membrane: semi-permeable membrane that separates the cell from its environment
Cytoplasm: gel-like substance inside the cell where metabolic processes occur
Cytoskeleton: network of filaments that provides structural support and shape to the cell
Organelles: specialized structures within the cell that perform specific functions
- Nucleus: contains genetic material (DNA)
- Mitochondria: site of cellular respiration (energy production)
- Endoplasmic reticulum (ER): involved in protein synthesis and transport
- Ribosomes: site of protein synthesis
- Lysosomes: contain digestive enzymes for breaking down cellular waste

Passive transport: movement of molecules from high to low concentration without energy input
- Diffusion: random movement of molecules across the membrane
- Osmosis: movement of water molecules across the membrane
- Facilitated diffusion: assisted transport of molecules across the membrane
Active transport: movement of molecules against their concentration gradient using energy
- Carrier proteins: transport molecules across the membrane
- Pumping: transport of molecules using energy from ATP

Mitosis: process of cell division that results in two daughter cells with identical DNA
- Interphase: cell grows and prepares for cell division
- Prophase: chromosomes condense and nuclear envelope breaks down
- Metaphase: chromosomes align at the center of the cell
- Anaphase: sister chromatids separate and move to opposite poles
- Telophase: nuclear envelope reforms and chromosomes uncoil
- Cytokinesis: cytoplasm divides and cell splits
Meiosis: process of cell division that results in four daughter cells with unique DNA combinations (gametes)
- Similar to mitosis, but with two rounds of cell division and crossing over of chromosomes

Signal transduction: process of transmitting signals from outside the cell to inside the cell
- Receptors: proteins on the cell surface that bind to signaling molecules
- Signal transduction pathways: series of molecular interactions that transmit signals
- Response: cell's response to the signal, such as changes in gene expression or protein activity

Photosynthesis: process of converting light energy into chemical energy
- Occurs in chloroplasts, organelles found in plant cells
Cellular respiration: process of generating energy from glucose
- Occurs in mitochondria, found in all eukaryotic cells

The plasma membrane is semi-permeable, separating the cell from its environment
Cytoplasm is a gel-like substance inside the cell where metabolic processes occur
The cytoskeleton is a network of filaments providing structural support and shape to the cell
Organelles are specialized structures within the cell with specific functions

Diffusion is the random movement of molecules across the membrane
Osmosis is the movement of water molecules across the membrane
Facilitated diffusion is the assisted transport of molecules across the membrane

Similar to mitosis, but with two rounds of cell division and crossing over of chromosomes
Results in four daughter cells with unique DNA combinations (gametes)

Signal transduction is the process of transmitting signals from outside the cell to inside the cell
Receptors are proteins on the cell surface that bind to signaling molecules
Signal transduction pathways are series of molecular interactions that transmit signals
Response: cell's response to the signal, such as changes in gene expression or protein activity