Cell Organelles
Organelle | Location | Features | Role |
Capsule | Covers the cell wall of some bacteria. | Viscous cell envelope polysaccharide. | Determines the degree of pathogenicity of the bacteria. |
Cell wall | Coats the cell membrane of plant cells, bacteria, cyanobacteria, and fungi. | Rigid structure consisting of cellulose in plant cells, peptidoglycan in bacteria, and chitin in most fungi (except mycoplasmas). | Provides rigidity and allows the passage of water, air, and dissolved materials. Cells walls have holes allowing material passage between cells. |
Cell membrane | Surrounds the cytoplasm of all cells. | Double unit membrane composed of phospholipids, proteins, and carbohydrates. | Surrounds the cytoplasm, provides protection, and controls the passage of substances through various transport mechanisms: diffusion, osmosis, facilitated diffusion, endocytosis, and exocytosis (active transport). |
Cilia | Found in the membranes of protozoa and the ciliated epithelium of the upper airways of mammals. | Small hairs formed by nine bundles of microtubules (9+2 arrangement) and composed of tubulin. | Used for locomotion and the mobilization of materials (e.g., in the intestine, trachea, bronchi). In protozoa, they are used for catching food. |
Flagella | Located in the cell membrane of bacteria, protozoa, some fungi, algae, and sperm. | Long, whip-shaped structures of protein. Prokaryotic flagella have a different structure and protein composition (flagellin) than eukaryotic flagella (tubulin, 9+2 arrangement). | Used for locomotion and food capture. |
Pili | Located in the membrane of some bacteria. | Small villi of pilin protein. | Have a locking function. In bacteria, they are involved in conjugation. |
Endoplasmic reticulum | Located inside the cell, communicating with the outside. | A network of membranes; lipoprotein structure similar to the cell membrane. | Participates in protein synthesis and transports materials to the Golgi apparatus. |
Golgi apparatus | Located in the cytoplasm near the nucleus. | Series of flat sacs; lipoprotein membrane. | Stores and secretes lipids and proteins. |
Ribosomes | Found free in the cytoplasm or attached to the RER membranes. | Spherical structures formed by two subunits of different molecular weight, originating from the nucleolus. | Actively involved in protein synthesis using ribosomal ribonucleic acid (rRNA). |
Lysosomes | Found suspended in the cytoplasm. | They are spherical structures surrounded by a membrane, are produced by the Golgi apparatus, in its interior are hydrolytic enzymes. | They are implicit in the digestion of macromolecules such as lipids, polysaccharides, proteins and nucleic acids. |
Plastids | They are found in the cytoplasm of both cells and plants dealgas. | Membranous structures lipoprotein chemical composition, which can contain inside pigments, enzymes and / or ions. | They serve as storage (*) of proteins, lipids or starch (Leucoplast) or pigment (chromoplasts). In the case of chloroplasts involved in the anabolic process of photosynthesis. |
Mesosoma | They function as parainicio zone of cell division. | In some bacterial cells the cell membrane folds spiral inward (invagination), giving rise to these structures is their chemical composition lipoprotein. | It participates in cell division, equitably distributing the genetic material to two daughter cells. |
Mitochondria | Immersed in the cytoplasm of cells. | Double membrane organelle where the inner mitochondrial cristae form lipoprotein chemical composition, on the crests are the electron carriers in the mitochondrial matrix and a large number of enzymes. Mitochondria contain their own DNA, separate from the nucleus. | Within the mitochondrial matrix are performed metabolic chemical reactions of the Krebs cycle citric acid. While peaks in the mitochondrial respiratory chain occurs, here also occurs oxidative phosphorylation. The mitochondrion is also known as the “powerhouse” because it is the greatest amount of metabolic energy in the form of adenosine triphosphate (ATP). |
Vacuole | Be located in the cytoplasm of animal and plant cells. | Membranous structures simple chemical nature lipoprotein, spherical in shape. | Storage, digestive, excretory and osmoregulatory (contractile). |
Centriole | Located near the nucleus. | Are tubular structures of protein chemical nature. | During cell division the centriole divides and gives rise to the asters, which are produced fibers or mitotic spindle. |
Cytoskeleton | It is located within the cytoplasm. | Protein chemistry interconnections in nature, so stringy. | Maintains three-dimensional shape of the fixed cell organelles and allows internal traffic. |
Core | Central position, tending toward the upper region. | Spherical structure and size varied, in eukaryotic cells show a nuclear membrane with pores, enclosing the nucleoplasm, the nucleolus and the chromatin (DNA) are also enzymes and proteins. In prokaryotic cells no nuclear membrane | Coordinates metabolic processes, reproduction and heredity, which is considered the control center of the cell |
Nucleolus | Within the nucleus. | Spherical structure, chemical composition based on | From this sesintetiza RNA and RNA r t. |