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.).
Glycocalyx
sugary coat formed by the glycolipds and glycoproteins. Function 1. important in cell recognition 2. Cell adherence 3. protection from digestion by enzymes in the extracellular fluid
Phospholid Head
Like seeks like; so the phospholipid molecules arrange themselves in the bilayer so the hydrophilic heads face the outward; so they contact watery fluid on either side of the membrane (cytosol - inside extracellular fluid on - outside
Phospholid Tail
These will point toward one another creating a nonpolar; hydrophobic region in the membrane’s interior
Integral Proteins
extend into or through the lipid bilayer and are firmly imbedded in it
Periperheral Proteins
not as firmly embedded in the membrane; attached to the polar heads of membrane lipids or to integral proteins at the inner or outer surface of the membrane
Cytoskeleton Filaments
The cytoskeleton is a network of three types of protein - filaments; microfilaments; intermedidate filaments; and microtubles - that extend throughout the cytoplasm. IF - are thicker than micro filaments but thinner than microtubles
Cholesterol
Classified as a lipid; the most abundant steriod in animal tissues; located in cell membranes and used for the synthesis of steroid hormones and bile salts
Glycolipid
carbohydrate groups form a “polar head”; fatty acid tails are nonpolar; appear only in the membrane layer that faces the extracellular fluid
Glycoprotein
proteins with carbohydrate groups attached to the head
Lipid Bilayer
basic structural framework of the plasma membrane
Interphase
Period between cell divisions; chromosomes not visable under light microscope
Cytokinesis
Cytoplasmic division; contractile ring forms cleavage furrow around center of cell; dividing cytoplasm into separate and equal portions
Sister Chromtids
two identical copies of a single replicated chromosome that are connected by a centromere.
Centromere
A constricted region that holds the chromatid pair together
Asters
A star-shaped cluster of microtubules radiating from the pericentriolar region; and seen immediately before and during mitosis of an animal cell.
Kinetochores
A protein complex that is outside of each centromere
Polar Microtubles
the remaining spindle microtubles not attached to any chromosomes
Active Transport
This is the movement of molecules (polar or charged solutes) “uphill” or against their concentration gradients. This is considered active transport because energy (ATP) is required for carrier proteins to move solutes across the membrane
Passive Transport
A substance moves down its concentration or electric gradient using its own kinetic energy
Simple Diffusion
A passive process in which substances must move through the lipid bilayer of the plasma membrane without the help of membrane transport protein
Facilitate Diffusion
A passive process of transpot in which and integral protein assits a specific substance across the membrane
Symport
transpot of two substances in the SAME direction (Na+glucose & Na+ Amino Acid acid supporters)
Antiport
transpot of two substances in the OPPOSITE direction (Na+ Ca+)
Uniport
transport of a molecule or ion through a membrane by a carrier mechanism without known coupling to the transport of any other molecule or ion.
Secondary Active Transport
energy stored in a Na+ or H+ concentration gradient is used to drive other substances across the membrane against their concentration gradients
Primary Active Transport
energy derived from hydolysis of ATP leads to a conformation change in the slope of the protein; “pumping” a substance across the membrane
Osmosis
A type of passive diffusion in which there is net movement of a solvent through a selectively permeable membrane
Hypertonic
place RBC in a solution that has higher concentration of solutes; than the cytosol of the RBC; there will be a net movement of water out of the cells. The cells will shrink or “crenate”
Hypotonic
place RBC in a solution with a lower concentration of solutes than the cytosol of the RBC; there will be a net movement of water into the cells. The cell will swell and eventually burst; also called hemolysis. Pure water is hypotonic and would cause rapid hemolysis
Isotonic
Any solution in which a cell (ex. RBC) maintains its normal shape and volume
Phagocytosis
a form of endocytosis in which the cell engulfs TO EAT large; solid particles; such as worn out cells; whole bacteria; viruses
Pinocytosis
or bulk-phase endocytosis; a form of endocytosis in which tiny droplets if ECP are taken up
Receptor-mediated Endocytosis
a form of endocytosis that is highly selective;; cells bind to specific ligands
