AP Bio- CH. 6 (Organelles and such..)

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?

cytoskeletal structures

Golgi apparatus

consists of flattened membranous sacs; receives transport vesicles from the ER and the modifies those ER products; produces certain molecules; produces lysosomes and secretory vesicles

peroxisome

contains enzymes that transfer hydrogen from substrates to oxygen producing H2O2; detoxifies alcohol; contains enzymes(catalase) that convert H2O2 to H20 and O2

central vacuole

contains hydrolytic enzymes; sequesters dangerous by-products; contains soluble pigments; stores water; involved in cell growth

nucleus

contains most of the genes that control the eukaryotic cell; generally the most conspicuous organelle in a eukaryotic cell; contains the nucleolus and chromatin

digestive enzymes

contents of lysosomes

molecules to become exported (waste)

contents of secretory vesicles

molecules used within the cell

contents of transition vesicles

chromosomes

consist of DNA and proteins; tightly coiled; condensed

chromatin

consists of DNA and proteins; condenses to form chromosomes

cilia

9+2 arrangement of microtubules; shorter and many per cell; produce an oar-like motion

Both the volume and the surface area for three different cells were measured. These values are listed in the following table: Volume Surface Area Cell 1 9.3 µm3 26.5 µm2 Cell 2 12.2 µm3 37.1 µm2 Cell 3 17.6 µm3 40.6 µm2 Using data from the table above, select the best explanation for why that cell will be able to eliminate waste most efficiently?

Cell 2 since it has the highest surface area-to-volume ratio which facilitates the exchange of materials between a cell and its environment.

Centrioles, cilia, flagella, and basal bodies have remarkably similar structural elements and arrangements. Which of the following hypotheses is most plausible in light of such structural similarities?

Cilia and flagella arise from the centrioles.

Which of the following produces and modifies polysaccharides that will be secreted?

Golgi apparatus

A mutation that disrupts the ability of an animal cell to add polysaccharide modifications to proteins would most likely cause defects in its

Golgi apparatus and extracellular matrix.

Why isn't the mitochondrion classified as part of the endomembrane system?

Its structure is not derived from the ER or Golgi

Which of the following makes it necessary for animal cells, although they have no cell walls, to have intercellular junctions?

Maintenance of tissue integrity and barriers to fluid leakage requires cells to adhere tightly to one another

Which of the following statements about the cytoskeleton is true?

Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other.

Secretory Vesicle

Origin: Golgi apparatus Contents: waste Destination: outside the cell

Which of the following statements correctly describes some aspect of protein secretion from prokaryotic cells?

Proteins that are secreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane

Gaucher disease is the most common of lipid storage diseases in humans. It is caused by a deficiency of an enzyme necessary for lipid metabolism. This leads to a collection of fatty material in organs of the body including the spleen, liver, kidneys, lungs, brain, and bone marrow. Using your knowledge of the structure of eukaryotic cells, identify the statement below that best explains how internal membranes and the organelles of cells would be involved in Gaucher disease.

The lysosomes lack sufficient amounts of enzymes necessary for the metabolism of lipids.

The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is a characteristic common to all of these extracellular structures?

They are constructed of polymers that are synthesized in the cytoplasm and then transported out of the cell.

What do the cell walls of plants and the extracellular matrix of animal cells have in common?

They have functional connections with the cytoskeleton inside the cell.

How does the cell multiply its peroxisomes?

They split in two after they become sufficiently large

The nuclear lamina is an array of filaments on the inner side of the nuclear membrane. If a method were found that could cause the lamina to fall into disarray, what would you expect to be the most likely immediate consequence?

a change in the shape of the nucleus

free ribosomes

consist of 2 subunits; composed of rRNA and proteins;produce proteins for use within the cell; suspended in the cytosol

Which of the following contain the 9 + 2 arrangement of microtubules, consisting of nine doublets of microtubules surrounding a pair of single microtubules?

both flagella and motile cilia

transport vesicles

carries ER products to the Golgi

secretory vesicle

carries golgi modified products to the cell membrane; fuses with the cell membrane releasing the contents to outside the cell

Which of the following correctly matches an organelle with its function?

central vacuole ... storage

Which organelle or structure is absent in plant cells?

centrosomes

rough ER

channels proteins to transport vesicles; attaches carbohydrate to some proteins; involved in membrane production through the production of vesicles

Thylakoids, DNA, and ribosomes are all components found in

chloroplasts

A biologist ground up some plant leaf cells and then centrifuged the mixture to fractionate the organelles. Organelles in one of the heavier fractions could produce ATP in the light, whereas organelles in the lighter fraction could produce ATP in the dark. The heavier and lighter fractions are most likely to contain, respectively,

chloroplasts and mitochondria.

intermediate filament

composition varies; more permanent and intermediate in diameter; reinforces cell shape and may fix organelle position

bound ribosomes

consist of 2 subunits; composed of rRNA and proteins; produce proteins for export; attached to rough ER

food vacuole

destination of lysosomes

outside the cell

destination of secretory vesicles

Golgi or inside the cell

destinations of transition vesicles

chromatin

dispersed;uncoiled;decondensed

nuclear envelope

double membrane that forms the boundary between the nuclear contents and the cytoplasm; perforated with pores

The evolution of eukaryotic cells most likely involved

endosymbiosis of an aerobic bacterium in a larger host cell-the endosymbiont evolved into mitochondria.

cell membrane

forms the boundary of the cell; acts as a selective barrier allowing certain materials to pass but not others

Gap junctions

found in animal cells form channels between cells found in embryos, cardiac muscle tissue, and endocrine glands. permit intercellular transport

Tight Junctions

found in animal cells hold cells tightly together block intercellular transport of material found in the lining of the digestive tract and the blood brain barrier found in skin cells glycoprotein filaments (intermediate) penatrate and bind to plasma membranes of two adjacent cells

Desmosomes

found in animal cells rivet cells together well developed in cells subjected to considerable mechanical force

Plasmodesmata

found in plant cells allow free passage of water and small solutes between cells

Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells?

gap junctions

Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through

gap junctions.

how does the function of the central vacuole in plant cells differ from the function of vacuoles in animal cells

in plant cells it stores water and maintains turgity, its also alot larger in animal cells its smaller and contains ions, water, and waste

In a plant cell, DNA may be found

in the nucleus, mitochondria, and chloroplasts

The extracellular matrix is thought to participate in the regulation of animal cell behavior by communicating information from the outside to the inside of the cell via which of the following?

integrins

Signals from the ECM to the cytoskeleton may be transmitted by

integrins.

flagella

involved in movement;longer and only one or two per cell; produce snake-like motion

smooth ER

synthesizes lipids including phospholipids and steroids; metabolizes carbohydrates; detoxifies durgs and poisons; stores calcium ions

microfilaments

involved in muscle contraction and localized cell contractions; form 3D support network just inside the cell membrane; solid rods made of actin; can divide an animal cell in two by forming a contractile ring; produces cytoplasmic streaming

The volume enclosed by the plasma membrane of plant cells is often much larger than the corresponding volume in animal cells. The most reasonable explanation for this observation is that

lant cells contain a large vacuole that adds to the volume of the cytoplasm.

Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large, complex, undigested lipids. Which cellular organelle must be involved in this condition?

lysosome

Which of the following contains hydrolytic enzymes?

lysosome

Hydrolytic enzymes must be segregated and packaged to prevent general destruction of cellular components. In animal cells, which of the following organelles contains these hydrolytic enzymes?

lysosomes

microtubules

make up spindle fibers,centrioles, cilia, and flagella; made of tubulin; straight, hollow tubes; involved in cell transport; provide tracts for organelle movement

lysosome

membrane bound sac of hydrolytic enzymes; enzymes are used to digest food, other molecules, and old, worn out cell parts

vacuole

membrane bound sacs; larger than vesicles and store materials

The differences among the three categories of cytoskeletal elements outlined in the table above would suggest that each of the following has specialized roles. Which of the following is a correct match? (All three elements are involved in the maintenance of cell shape.)

microtubules and chromosome movement

Movement of vesicles within the cell depends on what cellular structures?

microtubules and motor proteins

Which plant cell organelle contains its own DNA and ribosomes?

mitochondria

What types of proteins are not synthesized in the rough ER?

mitochondrial proteins

Which organelle is the primary site of ATP synthesis in eukaryotic cells?

mitochondrion

Cytochalasin D is a drug that prevents actin polymerization. A cell treated with cytochalasin D will still be able to

move vesicles around the cell.

A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from

nearly any eukaryotic organism.

One of the key innovations in the evolution of eukaryotes from a prokaryotic ancestor is the endomembrane system. What eukaryotic organelles or features might have evolved as a part of, or as an elaboration of, the endomembrane system?

nuclear envelope

The chemical reactions involved in respiration are virtually identical between prokaryotic and eukaryotic cells. In eukaryotic cells, ATP is synthesized primarily on the inner membrane of the mitochondria. In light of the endosymbiont theory for the evolutionary origin of mitochondria, where is most ATP synthesis likely to occur in prokaryotic cells?

on the plasma membrane

Golgi

origin of lysosomes

Golgi-

origin of secretory vesicle

ER

origin of transition vesicles

transition vesicle

origin: ER Contents: Molecules used within the cell Destination: golgi or inside the cell

Lysosome

origin: Golgi apparatus contents: digestive enzymes destination: food vacuole

extracellular matrix

outside of the cell made of many strong protein fibers that serve as binding mechanisms between two cells

centrioles

paired structures found in animal cells; consist of microtubules in a 9+0 arrangement; involved in cell division

Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen?

peroxisome

All of the following serve an important role in determining or maintaining the structure of plant cells. Which of the following are distinct from the others in their composition?

plant cell walls

Which type of organelle is found in plant cells but not in animal cells?

plastids

When a potassium ion (K+) moves from the soil into the vacuole of a cell on the surface of a root, it must pass through several cellular structures. Which of the following correctly describes the order in which these structures will be encountered by the ion?

primary cell wall → plasma membrane → cytoplasm vacuole

A cell with a predominance of free ribosomes is most likely

producing primarily cytoplasmic proteins

cell wall

protective layer external to the cell membrane; consists of cellulose

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

proteins

ECM proteins are made by ribosomes in which part of a eukaryotic cell?

rough ER

Which structure is the site of the synthesis of proteins that may be exported from the cell?

roughER

A biologist wants specifically to examine the surfaces of different types of cells in kidney tubules of small mammals. The cells in question can be distinguished by external shape, size, and 3-D characteristics. Which of the following would be the optimum method for her study?

scanning electron microscopy

Vinblastine, a drug that inhibits microtubule polymerization, is used to treat some forms of cancer. Cancer cells given vinblastine would be unable to

separate chromosomes during cell division.

central vacuole

serves a very important role of structural support along with storage, waste disposal, protection and growth; in plant cells

mitochondria

site of cellular respiration; produces ATP from sugars, fats, and other fuels

chloroplast

site of photosynthesis; produce food using light energy, CO2 and H2O

bound ribosomes

site of protein synthesis; attached to the outside surface of the endoplasmic reticulum; produces proteins for use outside the cell or for use in the cell membrane

free ribosomes

site of protein synthesis; suspended in the cytosol; produces proteins for the use within the cell

vacuoles

smaller and more plentiful structures found in animal cells; used for temporary storage and transporting substances

he liver is involved in detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and therefore abundant in liver cells?

smooth ER

Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids?

smooth endoplasmic reticulum

What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?

standard light microscopy

cytoplasm

the entire region between the nucleus and the cell membrane; consists of cytosol

The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by

the function of the Golgi apparatus in sorting and directing membrane component

In a liver cell detoxifying alcohol and some other poisons, the enzymes of the peroxisome remove hydrogen from these molecules and

transfer the hydrogen to oxygen molecules to generate hydrogen peroxide.

Cells require which of the following to form cilia or flagella?

tubulin

lysosomes, centrosomes(with centrioles), flagella

what do animal cells contain that plant cells do not?(3)

chloroplasts, central vacuole, cell wall, plasmodesmata

what do plant cells contain that animal cells do not?(4)

nucleolus

where the components of the ribosomes are made and assembled; found in the nucleus

Which of the following clues would tell you if a cell is prokaryotic or eukaryotic?

whether or not the cell is partitioned by internal membranes