A&P - Lab 2 Flashcards
Ribosome
Tiny spherical bodies composed of RNA and protein; floating free or attached to a membranous structure (the rough ER) in the cytoplasm. Actual sites of protein synthesis
Smooth Endoplasmic Reticulum
extends from the rough ER to form a network of membrane tubules. Smooth ER does not have ribosomes on the outer surface of its membrane. However; contains unique enzymes that it functionally more diverse than rough ER
Rough Endoplasmic Reticulum
contiguous with the nuclear membrane and usually is folded into a series of flattened sacs. The outer surface of rough ER is studded with ribsomes; the sites of protein synthesis
Golgi Apparatus
Stack of flattened sacs with bulbous ends and associated small vesicles; found close to the nucleus. Plays a role in packaging proteins or other substances for export from the cell or incorporation into the plasma membrane and in packaging lysomal enzymes
Lyosomes
Various-sized membranes sacs containing digestive enzymes including acid hydrolases; function to digest worn - out organelles and foreign substances that enter the cell. Have the capacity of total cell destruction if ruptured.
Peroxisomes
Small lyosome-like membranous sacs containing oxidase enzymes that detoxify alcohol; hydrogen peroxide; and other harmful chemicals
Mitochondria
Generally rod-shaped bodies with a double membrane wall; inner membrane is thrown into folds; or cristae; contain enzymes that oxidize foodstuffs to produce cellular energy (ATP); often referred to as “powerhouses of the cell”
Cristae
Crests or ridged structure. A small elevation in the ampulla of each semicircular duct that contains receptors for dynamic equilibrium
Centrioles
Paired; cylindrical bodies lie at right angles to each other; close to the nucleus. As part of the centrosome; they direct the formation of the mitotic spindle during cell division; form the bases of cilia and flagella
Cytoskeletal elements
Provide cellular support; function in the intracellular transport
Microfilaments
Formed largely of actin; a contractile protein; and thus are important in cell mobility; particularly in muscle cells
Intermediate filaments
Stable elements composed of a variety of proteins and resist mechanical forces acting on cells
Microtubules
Form the internal structure of the centrioles and help determine cell shape
Nucleus
A spherical or oval organelle of a cell that contains the hereditary factors of the cell; called genes. A cluster of unmyelinated nerve cell bodies in the central nervous system. The central part of an atom made up of protons and neutrons
Nuclear Envelope
the double membrane surrounding the nucleus within a cell.
Nuclear Pores
any of numerous structures with complex openings in a nuclear membrane which allow passage of molecules between the nucleus and surrounding cytoplasm; any of the numerous perforations in a nuclear membrane which allow materials to flow in and out
Nucleolus
Spherical body within a cell nucleus composed of protein; DNA; and RNA that are the sites of the assembly of small and large ribosomal subunits.
Plasma membrane
Outer; limiting membrane that seperates the cell’s internal parts from extracellular fluid or the external environment
Microvilli
Microscopic; finger-like projections of the plasma membranes of cells that increase surface area for absorption; especially in the small intestine and proximal convoluted tubles of the kidneys
Flagella
Hair like; projections that generally move an entire cell
Cytoplasm
all the cellular contents between the plasma membrane and the nucleus
Extracellular Fluid
Any fluid not contained within cells; which includes plasma; interstitial fluid and any fluid contained within a natural cavity (e.g.; joint fluid; CSF; pleural fluid; pericardial fluid; etc.).