Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.


Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.

Remove ads
Don't know
Know
remaining cards
Save
0:01
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
Retries:
restart all cards




share
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

ch. 4

Molecular Biology

QuestionAnswer
light microscope (lm) visible light is passed through the specimen and then through glass lenses. the lenses refract (bend) the light in such a way that the image of the specimen is magnified as it is projected into the eye or into a camera.
organelles the membrane-enclosed structures within eukaryotic cells.
electron microscope focuses a beam of electrons through a specimen or onto its surface.
transmission electron microscope (TEM) used to study the internal structure of cells. This microscope aims an electron beam through a very thin section of specimen.
scanning electron microscope (SEM) useful for detailed study of the topography of a specimen. Controlled by electromagnetic lenses, an electron beam scans the surface of the sample, usually coated in a thin coat of gold.
cell fractionation a technique for studying cell structure & function. The disruption of a cell and separation of its parts by centrifugation at successively higher speeds.
cytosol a semifluid jellylike substance found in all cells in which subcellular components are suspended.
nucleus this organelle is found in a eukaryotic cell and carries most of the DNA. this organelle is bounded by a double membrane.
Nucleoid a non-membrane enclosed region in a prokaryotic cell where its chromosome is located.
cytoplasm the contents of the cell enclosed by the plasma membrane; in eukaryotes the portion exclusive of the nucleus.
plasma membrane the membrane at the boundary of every cell that acts as a selective barrier, regulating the cells chemical composition.
flagellum motility structure present in some animal cells, composed of a cluster of microtubules w/in 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: microfilaments, intermediate filaments, microtubules.
microvilli projections that increase the cell's surface
peroxisome organelle wivarious specialized metabolic functions; produces hydrogen peroxide as a by product, then converts it to water.
mitochondrion the sites of cellular respiration, the metabolic process that uses oxygen to generate ATP by extracting sugars, fats, and other fuels.
lysosome digestive organelle where macromolecules are hydrolyzed.
Golgi apparatus organelle active in synthesis, modification, sorting, & secretion of cell products.
ribosomes complexes that make proteins; free in cytosol or bound to rough ER or nuclear envelope.
plasma membrane membrane enclosing the cell
chromatin material consisting of DNA & proteins; visible in a dividing cell as individual condensed chromosomes.
nucleolus nonmembranous structure involved in production of ribosomes; a nucleus has one or more nucleoli.
nuclear envelope double membrane enclosing the nucleus; perforated by pores; continuous with ER.
Endoplasmic reticulum network of membranous sacs and tubes; active in membrane synthesis and other synthetic and metabolic processes; has rough (studded with ribosomes) and smooth regions.
in animal cells, but not in plant cells: lysomes, centrosome, with centrioles flagella
in plant cells but not in animal cells: chloroplasts, central vacuole, cell wall, plasmodesmata
cell wall outer layer that maintains cells shape and protects cell from mechanical damage; made of cellulose, other polysaccharides and protein (found in plant cells).
plasmodesmata channels through cell walls that connect the cytoplasms of adjacent cells (found in plant cells)
chloroplast photosynthetic organelle; converts energy of sunlight to chemical energy stored in sugar molecules (found in plant cells)
central vacuole prominent organelle in older plant cells; functions include storage, breakdown of waste products, hydrolysis of macromolecules, enlargement of vacuole is a major mechanism of plant growth.
where are the eukaryotic cell's genetic instructions housed? in the nucleus and carried out by the ribosomes.
which cells have internal membranes that compartmentalize their functions? eukaryotic cells
which system regulates protein traffic and performs metabolic functions in the cell? endomembrane system
glycoproteins proteins that have carbohydrates covalently bonded to them.
phagocytosis a type of endocytosis in which large particulate substances or small organisms are taken up by a cell.
autophagy lysosomes use their hydrolytic enzymes to recycle the cell's own organic material.
endosymbiont theory this theory states that an early ancestor of eukaryotic cells engulfed an oxygen-using nonphotosynthetic prokaryotic cell. the evolutionary origins of mitochondria and chloroplasts.
Nuclear lamina A net like array of protein filaments that maintains the shape of the nucleus by mechanically supporting the nuclear envelope.
Chromosomes A cellular structure consisting of one DNA molecule and associated protein molecules.
Ribosomes Complexes made of ribosomal RNA and protein.
Free ribosomes Complexes suspended in cytosol
Bound ribosomes Complexes attached to the outside of the endoplasmic reticulum or nuclear envelope.
vesicles Sacs made of membrane
2 distinct regions of ER Smooth ER and rough ER
Smooth ER a region of ER that lacks ribosomes
Rough ER A region of ER that is studded with ribosomes
microtubules hollow tubes; consists of 13 columns of tubulin molecules. functions in the maintenance of a cells shape, cell motility, chromosome movements in cell division, & organelle movements
microfilaments 2 intertwined strands of actin, each a polymer of actin subunits. Functions in the maintenance of the cells shape, changes in cell shape, muscle contraction, cytoplasmic streaming in plant, cell motility, & division of animal cells.
intermediate filaments fibrous proteins that supercoiled into thicker cables, functions in the maintenance of a cells shape, anchorage of nucleus and certain other organelles, formation of nuclear lamina.
cristae an in-folding of the inner membrane of mitochondrion. the inner membrane houses electron transport chains and molecules of the enzyme catalyzing the synthesis of ATP.
mitochondria are responsible for chemical energy conversion
mitochondria and chloroplasts change energy from one form to another.
vacuoles are diverse maintenance compartments
the golgi apparatus is called the shipping and receiving center
the _________ _________ regulates protein traffic and performs metabolic functions in the cell. endomembrane system
The ________ ____________ genetic instructions are housed in the nucleus and carried out by the ribosomes. eukaryotic cell"s
_____ ______ have internal membranes that compartmentalize their functions. eukaryotic cells
thylakoid a flattened, membranous sac inside a chloroplast. thylakoids often exist in stacks called grana that are interconnected; their membranes contain molecular "machinery" used to convert light energy to chemical energy.
stroma the fluid outside of the thylakoid that contains the chloroplast DNA and ribosomes as well as many enzymes.
palstids One of a family of closely related organelles that includes chloroplasts, chromoplasts, and amyloplasts. plastids are found in the cells of photosynthetic eukaryotes.
motor proteins a protein that interacts with cytoskeleton elements and other cell components, producing movement of the whole cell or parts of the cell.
_____ _______ generally requires the interaction of the cytoskeleton with motor proteins. cell motility
centrioles found in pairs in the centrosome; each composed of 9 sets of triplet microtubules arranged in a ring.
cilia a short appendage containing microtubules in eukaryotic cells.
a ____ ______ is specialized for locomotion or moving fluid past the cell. the 9 + 2 arrangement. motile cilium
a _____ ______ is usually nonmotile and plays a sensory and signaling role. it lacks the 2 inner microtubules; the 9 + 0 arrangement. Primary cilium
actin a globular protein
basal body a eukaryotic cell structure consisting of 9 + 0 arrangement of microtubule triplets.
dynein in cilia and flagella, a large motor protein extending form one microtubule doublet to the adjacent doublet. ATP hydrolysis drives changes in the dynein shape that lead to bending of cilia and flagella.
The _____ is a network of fibers that organizes structures and activities in the cell. cytoskeleton
the 2 major roles of cytoskeleton support and motility
the role of peroxisomes Oxidation
Extracellular components and connections between cells help coordinate ______ _______. cellular activities
myosin a type of motor protein that associates into filaments that interact with actin filaments , causing cell contraction.
primary cell wall the thin and flexible first wall secreted by a plant.
middle lamella a thin layer rich in sticky polysaccharides called pectins.
secondary cell wall the wall, added by other cells, between the primary wall and the plasma membrane. this wall is often deposited in several laminated layers so it has a strong & durable matrix that affords the cell protection and support.
extracellular matrix the meshwork surrounding animal cells, consisting of glycoproteins, polysaccharides, and proteoglycans synthesized and secreted by the cells.
proteoglycan a large molecule consisting of a small core protein with many carbohydrate chains attached, found in extracellular matrix of animal cells.
collegan a glycoprotein in the extracellular matrix of animal cells that forms strong fibers, found extensively in in connective tissue and bone, the most abundant protein in the animal kingdom.
fibronectin an extracellular glycoprotein secreted by animal cells that helps them attach to the extracellular matrix.
integrin in animal cells, a transmembrane receptor protein with 2 subunits that interconnects the extracellular matrix and the cytoskeleton.
in animal cells, the 3 main types of cell junctions: tight, desmosomes, & gap
tight junction in animal cells, the plasma membranes of neighboring cells are very tightly pressed against each other, bound together by specific proteins.
desmosomes also called anchoring junctions, in animal cells, function like rivets, fastening cells together into strong sheets.
gap junctions in animal cells, provide cytoplasmic channels from one cell to an adjacent cell.
_____ _____ lack nuclei and other membrane-enclosed organelles. prokaryotic cells
organelles found in both plant and animal cells nucleus, Endoplasmic reticulum, Golgi apparatus, and mitochondria.
which structure is not part of the endomembrane system? nuclear envelope, chloroplast, Golgi apparatus, plasma membrane, ER chloroplast
which structure is common to plant and animal cells? Chloroplast, wall made of cellulose, central vacuole, mitochondrion, centriole mitochondrion
which of the following is present in a prokaryotic ell? mitochondrion, ribosome, nuclear envelope, chloroplast, ER ribosome
which structure-function pair is mismatched? nucleolus; production of ribosomal subunits, lysosome; intracellular digestion, ribosome; protein synthesis, microtubule; muscle contraction microtubule; muscle contraction
cyaninde binds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the? Mitochondria, ribosomes, peroxisomes, lysosomes, ER mitochondria
what is the most likely pathway to be taken by a newly synthesized protein that will be secreted by a cell? Golgi>ER>lysosome, nucleus>ER>Golgi, ER>Golgi>vesicles that fuse with plasma membrane, ER>lysosomes>vesicles that fuse with plasma membrane ER>Golgi>vesicles that fuse with plasma membrane
which cell is best for studying lysosomes? muscle cell, nerve cell, phagocytic white blood cell, leaf of a plant cell, bacterial cell phagocytic white blood cell
Created by: KellyClark