Structures of eukaryotic cell table 3.1 pg 69

Cell wall (absent in animal cells)

Composition: contains polysaccharides

Function: support and protection

Plasma membrane (cell membrane)

Composition: Phospholipid bilayer with embedded proteins

Function: Defines cell boundary; regulates molecule passage into and out of cells

Nucleus

Composition: Nuclear envelope, nucleoplasm, chromatin, and nucleoli

Function: Storage of genetic information; synthesis of DNA and RNA

Nucleoli

Composition: Concentrated area of chromatin, RNA, and proteins

Function: Ribosomal subunit formation

Ribosomes

Composition: Protein and RNA in two subunits

Function: Protein synthesis

Endoplasmic reticulum (ER)

Composition: Membranous flattened channels and tubular canals

Function: Synthesis and/or modification of proteins and other substances, and distribution by vesicle formation

Rough ER

Composition: Network of folded membranes studded with ribosomes

Function: Folding, modification, and transport of proteins

Smooth ER

Composition: Network of folded membranes having no ribosomes

Function: Various; lipid synthesis in some cells

Golgi apparatus (Golgi body)

Composition: stack of small membranous sacs (stack of pancakes)

Function: processing, packaging, distribution of proteins and lipids

Lysosomes (animal cells only)

Composition: membranous vesicle containing digestive enzymes

Function: intracellular digestion

Vacuoles and vesicles

Composition: membranous sacs of various sizes

Function: storage of substances

Peroxisomes

Composition: membranous vesicle containing specific enzymes

Function: various metabolic tasks

Mitochondria

Composition: inner membrane (cristae) bound by outer membrane

Function: cellular respiration

Chloroplasts (primarily in plant cells)

Composition: membranous grana bound by two membranes

Function: photosynthesis

Cytoskeleton

Composition: microtubules, intermediate filaments, actin filaments

Function: shape of cell and movement of its parts

Cilia and flagella (cilia are rare in plant cells)

Composition: 9 + 2 pattern of microtubules

Function: movement of cell

Centriole

Composition: 9 + 0 pattern of microtubules

Function: formation of basal bodies