1. Nucleus:
* Nuclear Envelope: A double membrane (two lipid bilayers) with pores that regulate the movement of molecules in and out of the nucleus.
* Chromatin: Composed of DNA and proteins (histones) that package and organize the genetic material.
* Nucleolus: A dense region within the nucleus responsible for ribosome synthesis.
2. Ribosomes:
* Ribosomal RNA (rRNA): A type of RNA that forms the structural framework of the ribosome.
* Proteins: Various proteins that contribute to the ribosome's structure and function.
3. Endoplasmic Reticulum (ER):
* Membrane: A network of interconnected membranes that form flattened sacs (cisternae) and tubules.
* Smooth ER: Lacks ribosomes; involved in lipid synthesis, detoxification, and calcium storage.
* Rough ER: Studded with ribosomes; involved in protein synthesis and modification.
4. Golgi Apparatus:
* Membrane: A stack of flattened membrane-bound sacs (cisternae).
* Enzymes: Contains a variety of enzymes that modify, sort, and package proteins and lipids.
5. Mitochondria:
* Outer Membrane: A smooth outer membrane.
* Inner Membrane: Folded into cristae, increasing surface area for ATP production.
* Matrix: The space within the inner membrane, containing enzymes involved in cellular respiration.
* Mitochondrial DNA (mtDNA): Contains genes for some mitochondrial proteins.
6. Lysosomes:
* Membrane: A single membrane that encloses a compartment filled with hydrolytic enzymes.
* Enzymes: Acid hydrolases that break down cellular waste, debris, and pathogens.
7. Peroxisomes:
* Membrane: A single membrane.
* Enzymes: Contains enzymes that break down fatty acids and detoxify harmful substances.
8. Vacuoles:
* Membrane: A single membrane called the tonoplast.
* Contents: Storage compartments for water, nutrients, waste products, and pigments.
9. Chloroplasts (Plant cells only):
* Outer Membrane: A smooth outer membrane.
* Inner Membrane: Contains thylakoids, stacked into grana, where photosynthesis occurs.
* Stroma: The space between the inner membrane and thylakoids, containing enzymes for carbon fixation.
* Chlorophyll: The pigment that absorbs light energy for photosynthesis.
10. Cell Wall (Plant cells only):
* Cellulose: A strong, fibrous polysaccharide that provides structural support.
* Hemicellulose and pectin: Other polysaccharides that contribute to the wall's structure.
Note: The composition of each organelle can vary slightly depending on the type of cell and its function.
