Cell Signaling: Cellular Communication

Study Notes

Cellular Processes

Cell Signaling

The process by which cells communicate with each other and respond to their environment
Involves signal transduction pathways, which allow cells to respond to stimuli
Types of cell signaling:
- Autocrine signaling: signals that affect the same cell that produced them
- Paracrine signaling: signals that affect nearby cells
- Endocrine signaling: signals that affect cells distant from the signaling cell
- Direct signaling: signals that directly affect adjacent cells

Cellular Transport

The movement of molecules into, out of, and within cells
Types of cellular transport:
- Passive transport: movement of molecules down their concentration gradient
  - Diffusion: random movement of molecules from high to low concentration
  - Osmosis: movement of water molecules from high to low concentration
- Active transport: movement of molecules against their concentration gradient
  - Requires energy input
  - Examples: pumps, carriers, and vesicle transport

Cell Division

The process by which a cell divides into two daughter cells
Types of cell division:
- Mitosis: division of somatic cells, resulting in two genetically identical daughter cells
- Meiosis: division of gametes (sperm or egg cells), resulting in four genetically unique daughter cells

Photosynthesis

The process by which cells convert light energy into chemical energy
Occurs in chloroplasts of plant cells and some algae
Equation: 6 CO2 + 6 H2O + light energy → C6H12O6 (glucose) + 6 O2

Cellular Respiration

The process by which cells convert glucose into energy (ATP)
Occurs in mitochondria of cells
Equation: C6H12O6 (glucose) + 6 O2 → 6 CO2 + 6 H2O + ATP (energy)

Protein Synthesis

The process by which cells create proteins
Involves transcription of DNA to RNA, and translation of RNA to protein
Steps:
1. Transcription: DNA → RNA
2. Translation: RNA → protein
3. Post-translational modification: protein folding and modification

Cellular Processes

Cell Signaling

Cell signaling involves signal transduction pathways, allowing cells to respond to stimuli
Types of cell signaling:
- Autocrine signaling: signals that affect the same cell that produced them
- Paracrine signaling: signals that affect nearby cells
- Endocrine signaling: signals that affect cells distant from the signaling cell
- Direct signaling: signals that directly affect adjacent cells

Cellular Transport

Cellular transport is the movement of molecules into, out of, and within cells
Passive transport: movement of molecules down their concentration gradient
- Diffusion: random movement of molecules from high to low concentration
- Osmosis: movement of water molecules from high to low concentration
Active transport: movement of molecules against their concentration gradient, requiring energy input
- Examples: pumps, carriers, and vesicle transport

Cell Division

Cell division is the process by which a cell divides into two daughter cells
Types of cell division:
- Mitosis: division of somatic cells, resulting in two genetically identical daughter cells
- Meiosis: division of gametes (sperm or egg cells), resulting in four genetically unique daughter cells

Photosynthesis

Photosynthesis converts light energy into chemical energy
Occurs in chloroplasts of plant cells and some algae
Equation: 6 CO2 + 6 H2O + light energy → C6H12O6 (glucose) + 6 O2

Cellular Respiration

Cellular respiration converts glucose into energy (ATP)
Occurs in mitochondria of cells
Equation: C6H12O6 (glucose) + 6 O2 → 6 CO2 + 6 H2O + ATP (energy)

Protein Synthesis

Protein synthesis involves transcription of DNA to RNA, and translation of RNA to protein
Steps:
- Transcription: DNA → RNA
- Translation: RNA → protein
- Post-translational modification: protein folding and modification

Description

Understand how cells communicate with each other and respond to their environment through signal transduction pathways. Learn about the different types of cell signaling, including autocrine, paracrine, endocrine, and direct signaling.