Cell Biology: Basic Unit of Life

Nucleus: Contains DNA, controls cell activities.
Mitochondria: Powerhouse of the cell, site of ATP production.
Ribosomes: Protein synthesis.
Endoplasmic Reticulum (ER):
- Rough ER: Studded with ribosomes, synthesizes proteins.
- Smooth ER: Synthesizes lipids, detoxifies.
Golgi Apparatus: Modifies, sorts, and packages proteins and lipids.
Lysosomes: Contain digestive enzymes for waste processing.
Cell Membrane: Semi-permeable barrier, regulates entry and exit of substances.
Cytoplasm: Jelly-like fluid, site of metabolic processes.

Mitosis: Process of somatic cell division, results in two identical daughter cells.
Meiosis: Process of gamete formation, results in four genetically diverse cells.

Catabolism: Breakdown of molecules to obtain energy.
Anabolism: Building up of molecules, requires energy.
Cellular Respiration: Conversion of glucose and oxygen into ATP, carbon dioxide, and water.

Passive Transport: Movement of molecules without energy (e.g., diffusion, osmosis).
Active Transport: Movement of molecules against a concentration gradient, requires energy (e.g., sodium-potassium pump).

Cells can differentiate into specialized types (e.g., muscle cells, nerve cells) based on gene expression and environmental factors.

Characterized by the absence of a nucleus and membrane-bound organelles.
Smaller and simpler than eukaryotic cells, facilitating rapid reproduction.
Genetic material is organized within a nucleoid region.
Examples include Bacteria and Archaea, which are some of the most ancient life forms.

These cells possess a true nucleus where DNA is stored, along with membrane-bound organelles.
Larger and more complex, allowing for compartmentalization of cellular processes.
Include various types such as plant cells (which have cell walls and chloroplasts), animal cells, fungal cells, and protist cells.

Nucleus: Responsible for housing DNA and regulating cellular activity.
Mitochondria: Known as the powerhouse, where ATP (energy currency) is generated.
Ribosomes: Sites of protein synthesis, found free in the cytoplasm or attached to the ER.
Endoplasmic Reticulum (ER):
- Rough ER: Studded with ribosomes for protein synthesis, involved in processing.
- Smooth ER: Lacks ribosomes, involved in lipid synthesis and detoxification processes.
Golgi Apparatus: Modifies, sorts, and packages proteins and lipids for secretion or use within the cell.
Lysosomes: Contain digestive enzymes to break down waste materials and cellular debris.
Cell Membrane: A semi-permeable barrier regulating the movement of substances in and out of the cell.
Cytoplasm: A gel-like substance where metabolic processes occur.

Mitosis results in two identical daughter cells, ensuring equal genetic material distribution.
Meiosis creates four genetically diverse gametes, essential for sexual reproduction.

Catabolism involves the breakdown of complex molecules to release energy.
Anabolism refers to the synthesis of larger molecules from smaller ones, requiring energy input.
Cellular Respiration transforms glucose and oxygen into ATP, along with carbon dioxide and water by-products.

Cells interact through chemical signals such as hormones and neurotransmitters.
Cell surface receptors recognize these signals and trigger appropriate responses.

Passive Transport occurs without energy expenditure, including processes such as diffusion and osmosis.
Active Transport requires energy to move substances against their concentration gradients, exemplified by the sodium-potassium pump.

Comprises interphase, divided into G1 (growth), S (DNA synthesis), and G2 (preparation for mitosis), along with the mitotic phase (M).
Checkpoints throughout the cycle ensure proper cell growth and division processes.