Cellular Organization (2) - HW - Section 10 TR

Complete a scheme of the integration of the main functions performed by the organelles of a cell.

(The arrangement of all these organelles in relation to each other is crucial. Life is an emergent property that results from the intricate organization and orchestrated functioning of cellular components.)

fundamental characteristics of life.

- to respond to the environment - to transform energy - to reproduce and pass along characteristics to offspring

Which of these structures stores, modifies, and packages products? A. A B. B C. C D. D E. E

A. A (The Golgi apparatus modifies, stores, and packages products of the ER.)

_____ is/are identical in structure to centrioles. A. Nuclear envelopes B. Basal bodies C. Mitochondria D. Chromatin E. Microfilaments

B. Basal bodies (Basal bodies and centrioles have identical structures.)

True or false? Proteins produced during the "chase" phase of a pulse-chase experiment are labeled with radioactive material. A. True B. False

B. False (During the chase phase, cells are provided with a large amount of nonradioactive material, so they are not labeled.)

Choose the letter that indicates the organelle that contains most of a cell's DNA. A. A B. B C. C D. D E. E

C. C (The nucleus contains most of a cell's DNA.)

Why does the phenomenon called "life" appear only at the level of the cell and not at the level of an organelle or an even smaller level? A. Not one of the cellular components could exist indefinitely on its own. Organelles should be guided by DNADNA or RNARNA to function properly. B. Smaller levels of organization cannot provide reproduction functions to pass traits to the offspring. C. Organelles require an enclosed space to function properly. Therefore, without the plasma membrane, life is impossible. D. Not one of the cellular components could exist indefinitely on its own. Organelles should interact with each other to function properly.

D. Not one of the cellular components could exist indefinitely on its own. Organelles should interact with each other to function properly.

Pancreatic cells, which secrete a large amount of digestive enzymes, are labeled with radioactive leucine and then chased for several hours with nonradioactive leucine. Photographic emulsions are prepared at different times during the chase. Where would the black spots appear on an emulsion prepared 3 hours after the pulse? A. Exterior of the cell B. Golgi apparatus C. Rough ER D. Secretory vesicles

A. Exterior of the cell (Black spots would appear on the exterior of the cell after 3 hours, indicating that the proteins had been secreted from the cell.)

What scientific hypotheses can be tested by a pulse-chase experiment? A. Movement of molecules through a cell over time B. The steady-state amount of protein in a cell C. The amino acid sequence of a protein D. Solubility of a molecule

A. Movement of molecules through a cell over time (Pulse-chase experiments allow for the tracking of molecules in a cell over time.)

Which of the following is a common trait of chloroplasts and mitochondria? A. both contain their own DNA B. both are surrounded by a single membrane C. both reproduce by meiosis D. both are found in plant and animal cells E. proteins for both are synthesized on ribosomes in the rough ER

A. both contain their own DNA (Mitochondria and chloroplasts contain their own DNA and ribosomes.)

Cyanide binds to at least one molecule involved in producing ATPATP. In a cell exposed to cyanide, most of the cyanide will be in A. mitochondria. B. ribosomes. C. peroxisomes. D. lysosomes.

A. mitochondria.

Mitochondria are found in __________. A. plant and animal cells B. all cells C. animal cells only D. animal cells and prokaryotic cells, but not plant cells E. plant cells only

A. plant and animal cells (Nearly all eukaryotic cells, including plant and animal cells, contain mitochondria.)

The _____ is a selective barrier, regulating the passage of material into and out of the cell. A. plasma membrane B. lysosome C. nucleus D. nuclear envelope E. chloroplast

A. plasma membrane (The plasma membrane regulates the passage of material into and out of the cell.)

Which of these organelles manufactures proteins bound for secretion out of the cell? A. rough endoplasmic reticulum B. lysosomes C. Golgi apparatus D. nucleolus

A. rough endoplasmic reticulum (The ribosomes associated with the rough ER synthesize secretory proteins bound for the exterior of the cell. Further processing and packaging occurs in the Golgi apparatus.)

Where is calcium stored? A. smooth endoplasmic reticulum B. rough endoplasmic reticulum C. microtubules D. centrioles E. mitochondria

A. smooth endoplasmic reticulum (In addition to storing calcium, the smooth ER also plays a role in detoxification and lipid synthesis.)

What path does a protein in the secretory pathway take, starting from its site of synthesis? A. Rough ER, secretory vesicles, Golgi apparatus, plasma membrane B. Rough ER, Golgi apparatus, secretory vesicles, plasma membrane C. Plasma membrane, secretory vesicles, Golgi apparatus, rough ER D. Golgi apparatus, rough ER, secretory vesicles, plasma membrane

B. Rough ER, Golgi apparatus, secretory vesicles, plasma membrane (Proteins are synthesized in the rough ER, modified in the Golgi apparatus, and carried in secretory vesicles to the plasma membrane, where they are secreted.)

Choose the best description of the cell cytoskeleton. A. The cell cytoskeleton is similar to an animal skeleton in providing rigid internal support and structure to the cell. B. The cell cytoskeleton is a dynamic network of fibers that can be quickly dismantled and reassembled to change cell shape and the position of cell components. C. The cell cytoskeleton serves as permanent scaffolding to anchor cell components into position within the cell cytoplasm.

B. The cell cytoskeleton is a dynamic network of fibers that can be quickly dismantled and reassembled to change cell shape and the position of cell components. (Read about the dynamic nature of the cytoskeleton and the interactions between its network of fibers.)

During a different pulse-chase experiment, photographic emulsions were prepared at different times during the chase, and radioactive spots were detected at the following times and locations: 5 minutes: rough ER; 10 minutes: Golgi apparatus; 40 minutes: endosomes; 70 minutes: lysosomes; 140 minutes: lysosomes. Which of the following conclusions can be drawn from these results? A. The proteins traveled from lysosomes to endosomes. B. The final destination of the proteins was the lysosome. C. The proteins did not travel through the Golgi apparatus. D. The proteins were secreted.

B. The final destination of the proteins was the lysosome. (This conclusion can be drawn from the results, since the radioactive spots were last detected at the lysosome, which is not a secretory vesicle.)

Which statement correctly describes the nuclear envelope of a eukaryotic cell? A. All of the proteins of the cell are synthesized on ribosomes bound on the nuclear envelope. B. The nuclear envelope is continuous with the endoplasmic reticulum. C. The nuclear envelope is a single membrane consisting of a phospholipid bilayer. D. The outer layer of the nuclear envelope is lined with a lamina. E. Plasmadesmata in the nuclear envelope permit the exchange of macromolecules between the nucleus and the cytoplasm.

B. The nuclear envelope is continuous with the endoplasmic reticulum.

The _____ is composed of DNA and protein. A. ribosome B. chromatin C. flagellum D. centriole E. mitochondrion

B. chromatin (Chromatin is composed of DNA and protein.)

What is the first step in a pulse-chase experiment? A. Preparing cells for electron microscopy B. Incubating cells with an unlabeled molecule C. Incubating cells with a labeled molecule D. Examining cells for the location of the labeled molecules

C. Incubating cells with a labeled molecule (Cells are first "pulsed" with a large amount of labeled material for a short time.)

Which statement about extracellular structures (plant cell walls and the extracellular matrix of animal cells) is correct? See Concept 6.7 (Page) A. All extracellular structures form barriers to separate adjacent cells. B. Proteins and lipids are common components of extracellular structures. C. Information can be transmitted from these extracellular structures to the cytoplasm. D. Extracellular structures store energy in the form of polysaccharides for subsequent metabolism by the cell. E. Extracellular structures regulate the passage of water molecules across the cell membrane.

C. Information can be transmitted from these extracellular structures to the cytoplasm. (Extracellular structures provide mechanical and chemical signals that are transmitted across the plasma membrane to the interior of the cell.)

Which one of the following statements about the endomembrane system is correct? A. The endoplasmic reticulum is continuous with the plasma membrane. B. Most of the phospholipids of the endomembrane system are synthesized in the mitochondria. C. Proteins that will be secreted from the cell are likely to be found in closed spaces bounded by membranes of the endomembrane system. D. Mitochondria function in the modification and sorting of lipids and proteins. E. Ribosomes move lipids and proteins among the different organelles of the endomembrane system.

C. Proteins that will be secreted from the cell are likely to be found in closed spaces bounded by membranes of the endomembrane system. (Proteins that will be secreted are always enclosed by some membrane of the endomembrane system until they are secreted.)

Which organelle plays a role in intracellular digestion? A. Golgi apparatus B. plasmodesma C. lysosome D. chloroplast E. ribosome

C. lysosome (The prefix "lyso-" means decomposition.)

Which of these provides the cell with structural support? A. A B. B C. C D. D E. E

D. D (Microfilaments are a component of the cytoskeleton.)

_____ aid in the coordination of the activities of adjacent animal cells. A. Keratin fibers B. Plasmodesmata C. Desmosomes D. Gap (communicating) junctions E. Tight junctions

D. Gap (communicating) junctions (Gap junctions allow for the passage of material between cells, thus facilitating communication between these cells.)

Which statement about extracellular structures (plant cell walls and the extracellular matrix of animal cells) is correct? See Concept 6.7 (Page) A. Extracellular structures store energy in the form of polysaccharides for subsequent metabolism by the cell. B. All extracellular structures form barriers to separate adjacent cells. C. Proteins and lipids are common components of extracellular structures. D. Information can be transmitted from these extracellular structures to the cytoplasm. E. Extracellular structures regulate the passage of water molecules across the cell membrane.

D. Information can be transmitted from these extracellular structures to the cytoplasm. (Extracellular structures provide mechanical and chemical signals that are transmitted across the plasma membrane to the interior of the cell.)

How does a cell display the fundamental characteristics of life? A. It is possible because all the functions performed by the cell are integrated and controlled by RNARNA. B. It is possible because the functions of a cell organelle can be partially performed by other organelles. This allows for stable cellular work. C. It is possible because all the nutrients that enter the cell take part in interconnected metabolic pathways. D. It is possible because all the functions performed by the individual structures and organelles of a cell are integrated.

D. It is possible because all the functions performed by the individual structures and organelles of a cell are integrated.

_____ are the sites of protein synthesis. A. Golgi apparatuses B. Peroxisomes C. Mitochondria D. Ribosomes E. Microfilaments

D. Ribosomes (Ribosomes are the site of protein synthesis.)

Which of these are hollow rods that shape and support the cell? A. peroxisomes B. microfilaments C. plasma membrane D. microtubules E. chloroplasts

D. microtubules (Microtubules are rods that also play a role in organelle movement.)

Ribosomal subunits are manufactured by the _____. A. rough endoplasmic reticulum B. smooth endoplasmic reticulum C. peroxisome D. nucleolus E. lysosome

D. nucleolus (Ribosomes are manufactured by the nucleolus.)

Which of these organelles produces H2O2 as a by-product? A. flagellum B. mitochondrion C. centrioles D. peroxisome E. nucleus

D. peroxisome (Peroxisomes produce hydrogen peroxide as a by-product of their metabolic processes.)

Which of these is the double membrane that encloses the nucleus? A. A B. B C. C D. D E. E

E. E (This is the nuclear envelope.)

Which of the following functions is NOT associated with the cytoskeleton in eukaryotic cells? See Concept 6.6 (Page) A. determining the shape of animal cells B. the contraction of muscle cells in animals C. the beating of cilia or flagella D. maintaining the position of the nucleus in the cell E. Movement of RNA molecules from the nucleus to the cytoplasm

E. Movement of RNA molecules from the nucleus to the cytoplasm (RNA molecules exit the nucleus via nuclear pores.)

Which of the following functions is NOT associated with the cytoskeleton in eukaryotic cells? See Concept 6.6 (Page) A. the contraction of muscle cells in animals B. determining the shape of animal cells C. maintaining the position of the nucleus in the cell D. the beating of cilia or flagella E. Movement of RNA molecules from the nucleus to the cytoplasm

E. Movement of RNA molecules from the nucleus to the cytoplasm (RNA molecules exit the nucleus via nuclear pores.)

The primary role of _____ is to bind animal cells together. A. gap (communicating) junctions B. tight junctions C. the cytoskeleton D. plasmodesmata E. desmosomes

E. desmosomes (The primary role of desmosomes (anchoring junctions) is to bind cells together.)

The cilia and flagella of eukaryotic cells are composed of _____. A. tonofilaments B. intermediate filaments C. pili D. microfilaments E. microtubules

E. microtubules (Eukaryotic cilia and flagella are composed of microtubules.)

Which of these organelles carries out cellular respiration? A. ribosomes B. nucleolus C. chromatin D. smooth endoplasmic reticulum E. mitochondrion

E. mitochondrion (Mitochondria convert the chemical energy of organic molecules to chemical energy in the form of ATP.)

Which of these cell junctions form a barrier to the passage of materials? A. plasmodesmata B. desmosomes (anchoring junctions) C. gap (communicating) junctions D. keratin fibers E. tight junctions

E. tight junctions (Tight junctions form a barrier that prevents fluids from moving between cells.)