functions and compositions of organelles/parts in a cell

Plasmalemma or Plasma Membrane

Composition: Lipid bilayer, with phospholipid (hydrophilic head hydrophobic tail) steroids, proteins, and carbs

Function: Isolate, structural support, sensitivity control entrance/exit of materials

Cytosol

Composition: fluid components of cytoplasm; may contain insoluble materials (ER, Mitochondria)

Function: Distributes materials by diffusion, stores glycogen, pigments, and other materials

Cytoskeleton

Composition: Proteins organized in fine filaments or slender tubes (microtubules/microfilaments)

Function: strength and support movement of cellular structures and materials

Microvilli

Composition: membrane extensions containing microfilaments

Function: Increased surface area to facilitate absorption of extracellular materials

centrosome

Composition: cytoplasm containing two centrioles, at right angles; each centriole is comprised of 9 microtubule triplets

Function: Essential for movement of chromosomes during cell division; organization of microtubules in cytoskeleton

Cillia

Composition: membrane extensions containing microtubule doublets in a 9+2 array

Function: Movement of materials over cell surface

Ribosomes

Composition: RNA + proteins; fixed ribosomes bound to rough ER free ribosomes scattered in cytoplasm

Function: Protein synthesis

Mitochondria

Composition: Double membrane, with inner membrane folds (cristae) enclosing metabolic enzymes

Function: Produces 95% of the ATP required by the cell

Nucleus

Composition: nucleoplasm containing nucleotides, enzymes, nucleoproteins, and chromatin surrounded by nuclear envelope with nuclear pores

Function: Control of metabolism; storage and processing of genetic information; controls proteins synthesis

nucleolus

Composition: Dense region in nucleoplasm contain DNA and RNA

Function: Site of rRNA synthesis and assembly of ribosomal subunits

Endoplasmic reticulum

Composition: Network of membranous channels extending throughout the cytoplasm (rough has ribosomes smooth does not)

Function: Synthesis of secretory products; intracellular storage and transport (rough ER: modification of newly synthesized proteins, Smooth ER: lipid, steroid, and carb synthesis also calcium ion storage)

Golgi apparatus

Composition: stacks of flattened membranes (cisternae) containing chambers

Function: Storage, alteration, and packaging of secretory products and lysosomal enzymes

Lysosome

Composition: Vesicles containing digestive enzymes

Function: Intracellular removal of damaged organelles or pathogens (trash can)

Peroxisome

Composition: Vesicles containing degradative enzymes

Function: Catabolism of fat and other organic compounds, neutralization of toxic compounds generated in the process