Organelles Quiz

Flagellum: motility structure present in some animal cells, composed of a cluster of microtubules within an extension of the plasma membrane

Centrosome: region where the cell’s microtubules are initiated; contains a pair of centrioles

Cytoskeleton: reinforces cell’s shape; functions in cell movement; components are made of protein. Includes: 1) microfilaments, 2) intermediate filaments, 3) microtubules

Microvilli: projections that increase the cell’s surface area

Peroxisome: organelle with various specialized metabolic functions; produces hydrogen peroxide as a by-product and then converts it to water

Mitochondrion: organelle where cellular respiration occurs and most ATP is generated

Endoplasmic Reticulum: network of membranous sac and tubes; active in membrane synthesis and other synthetic and metabolic processes; has rough (ribosome-studded) and smooth regions

Nuclear envelope: double membrane enclosing the nucleus; perforated by the pores; continuous with ER

Nucleolus: nonmembranous structure involved in production of ribosomes; a nucleus has one or more nucleoli

Chromatin: material consisting of DNA and proteins; visible in a dividing cell as individual condensed chromosomes

Plasma membrane: membrane enclosing the cell

Ribosomes (small brown dots): complexes that make proteins; free in cytosol or bound to rough ER or nuclear envelope

Golgi apparatus: organelle active in synthesis, modification, sorting, and secretion of cell products

Lysosome: digestive organelle where macromolecules are hydrolyzed

Cell wall: outer layer that maintains cell’s shape and protects cell from mechanical damage; made of cellulose, other polysaccharides, and protein

Central vacuole: prominent organelle in older plant cells; functions include storage, breakdown of waste products, and hydrolysis of macromolecules; enlargement of the vacuole is a major mechanism of plant growth

Chloroplast: photosynthetic organelle; converts energy of sunlight to chemical energy stored in sugar molecules

Plasmodesmata: cytoplasmic channels through cell walls that connect the cytoplasms of adjacent cells

Smooth Endoplasmic Reticulum: Synthesis, metabolism, detoxification, and storage

Rough Endoplasmic Reticulum: Secretion