Cell Biology Basics

Study Notes

Cell membrane: semi-permeable membrane that separates the cell from its environment
Cytoplasm: jelly-like substance inside the cell membrane where metabolic reactions occur
Nucleus: control center of the cell where DNA is stored
Mitochondria: organelles responsible for generating energy for the cell through cellular respiration
Endoplasmic reticulum (ER): organelle involved in protein synthesis and transport
Ribosomes: site of protein synthesis
Lysosomes: organelles responsible for cellular digestion and recycling

Golgi apparatus: organelle involved in protein modification and transport
Chloroplasts: organelles found in plant cells responsible for photosynthesis
Cytoskeleton: network of filaments that provides structural support and shape to the cell
Peroxisomes: organelles involved in the breakdown of fatty acids and amino acids

Mitosis: process of cell division that results in two daughter cells with the same number of chromosomes as the parent cell
Meiosis: process of cell division that results in four daughter cells with half the number of chromosomes as the parent cell
Cytokinesis: process of cell division that separates the cytoplasm and divides the cell into two daughter cells

Passive transport: movement of molecules from an area of high concentration to an area of low concentration without energy input
- 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 from an area of low concentration to an area of high concentration with energy input
- Carrier proteins: proteins that transport molecules across the cell membrane
- Pumps: proteins that use energy to transport molecules across the cell membrane

Signal transduction pathways: series of molecular interactions that allow cells to respond to stimuli
Hormone signaling: signaling between cells through the use of hormones
Neurotransmission: signaling between nerve cells through the use of neurotransmitters