Chapter 2). Cells: The Living Units

This organelle has both a cis and a trans face. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(A) Golgi apparatus

This organelle primarily modifies products from the rough ER, and it resembles a stack of hollow saucers, one cupped inside the next. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(A) Golgi apparatus

If integral proteins move molecules across the plasma membrane against their concentration gradient, this is called __________. (A) active transport (B) simple diffusion (C) facilitated diffusion (D) Osmosis

(A) active transport

The outer membrane of the nuclear envelope __________. (A) is continuous with smooth ER in the cytoplasm (B) forms from smooth ER after every cell division (C) is a specialized part of the rough ER (D) is lined by protein filaments that maintain the shape of the nucleus

(C) is a specialized part of the rough ER

Peroxisomes (A) are the toxic waste removal system of the cell. (B) are involved in the production of ATP. (C) contain some of the code necessary for their own duplication. (D) synthesize proteins for use outside the cell.

(A) are the toxic waste removal system of the cell.

Which of the following is not a cytoskeleton element? (A) centriole (B) intermediate filament (C) microtubule (D) microfilament

(A) centriole

The ________ face of the Golgi apparatus is ________ to receive spherical vesicles from the rough endoplasmic reticulum. (A) cis; convex (B) trans; convex (C) trans; concave (D) cis; flattened

(A) cis; convex

Cells that connect body parts or cover and line organs include __________. (A) fibroblasts, epithelial cells, and erythrocytes (B) epithelial cells, skeletal muscle cells, and smooth muscle cells (C) erythrocytes and reproductive cells (D) fat cells, macrophages, and neurons (E) macrophages, fibroblasts, and fat cells

(A) fibroblasts, epithelial cells, and erythrocytes

In chromatin, the DNA molecule wraps around proteins called (A) histones. (B) integral protein. (C) nucleotides. (D) codons.

(A) histones.

In the process of phagocytosis, the organelles whose enzymes break down ingested foreign cells are the (A) lysosomes. (B) smooth endoplasmic reticulum. (C) peroxisomes. (D) nucleoli.

(A) lysosomes.

Lipid droplets (one type of inclusion found in cells) resemble __________ and are found in __________ cells. (A) lysosomes; liver (B) glycosomes; dividing (C) peroxisomes; kidney (D) ribosomes; epithelial

(A) lysosomes; liver

Which cytoskeletal element forms the mitotic spindle? (A) microtubules (B) actin filaments (C) microfilaments (D) intermediate filaments

(A) microtubules

The double membrane structure is unique to the (A) mitochondrion. (B) peroxisome. (C) nucleolus. (D) lysosome.

(A) mitochondrion.

Which of the following statements accurately describes the function of the nuclear envelope? (A) separation of nucleoplasm and cytoplasm (B) protein synthesis (C) regulation of passage of substances into and out of the cell membrane (D) transcription of DNA

(A) separation of nucleoplasm and cytoplasm

Materials that are to be exocytosed by cells are enclosed in vesicles synthesized by the (A) ribosome. (B) Golgi apparatus. (C) mitochondrion. (D) nucleosome.

(B) Golgi apparatus.

Which of the following is a function of the plasma membrane? (A) It provides a complete barrier to all fat-soluble proteins, but not water-soluble proteins. (B) It acts as a receptor to bind specific molecules arriving from outside the cell. (C) It does not allow material to be transported outside the cell. (D) It provides a complete barrier to all water-soluble proteins, but not fat-soluble proteins.

(B) It acts as a receptor to bind specific molecules arriving from outside the cell.

Which statement best describes vesicle formation in the Golgi apparatus? (A) Vesicles arrive at the convex trans face and bud off the concave cis face. (B) The convex cis face receives vesicles from the rough endoplasmic reticulum (ER). New vesicles leave the Golgi apparatus by budding off the concave trans face. (C) Proteins produced by the rough ER are packaged in the Golgi apparatus into new vesicles that bud off the ends of the cisternae. (D) New vesicles arrive at the concave trans face of the Golgi apparatus.

(B) The convex cis face receives vesicles from the rough endoplasmic reticulum (ER). New vesicles leave the Golgi apparatus by budding off the concave trans face.

What is the fate of the vesicle produced in the Golgi apparatus by the process of a phagosome? (A) The vesicle is a secretory vesicle that releases its product outside of the cell. (B) The vesicle is a lysosome containing enzymes to be used to clean-up cellular debris. (C) The vesicle fuses to the plasma membrane to replace or repair a portion of the membrane. (D) The vesicle fuses with the rough ER to supply enzymes needed for protein production.

(B) The vesicle is a lysosome containing enzymes to be used to clean-up cellular debris.

Which of the following describes the function of microfilaments? (A) They resist tension forces acting on the cell. (B) They are involved in muscle contraction and intracellular movement. (C) They form centrioles and support the cell and give it shape. (E) They link adjacent cells together by attaching to cell junctions called desmosomes. (F) None of the responses listed is correct.

(B) They are involved in muscle contraction and intracellular movement.

Which of the following statements about integral proteins in the plasma membrane is false? (A) Most extend all the way through the membrane. (B) They are more abundant by volume than the membrane phospholipids. (C) Some attach to the glycocalyx. (D) They determine which molecules are transported through the membrane.

(B) They are more abundant by volume than the membrane phospholipids.

Phospholipids of the plasma membrane are arranged (A) around a central layer of cholesterol. (B) as a bilayer with their nonpolar tails sandwiched between the polar heads. (C) as a bilayer with their polar heads sandwiched between the nonpolar tails. (D) in a single layer with polar heads facing outwards.

(B) as a bilayer with their nonpolar tails sandwiched between the polar heads.

Organelles are moved within the cytoplasm by being pulled along microtubules by the motor proteins __________ and __________. (A) rough ER; smooth ER (B) dyneins; kinesins (C) actin; myosin (D) DNA; RNA (E) glycosomes; lysosomes

(B) dyneins; kinesins

The plasma membrane is important for all the following reasons except (A) it separates the ECF from the ICF. (B) it is an important site for DNA transcription. (C) it determines what substances enter and exit the cell. (D) it acts as a site for cell-to-cell interaction and recognition.

(B) it is an important site for DNA transcription.

These organelles are often called the "demolition crew" of the cell. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(B) lysosome

This organelle is defective in the inherited disorder Tay-Sachs disease. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(B) lysosome

This organelle is primarily a sac of powerful digestive enzymes called acid hydrolases. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(B) lysosome

When a phagocytic white blood cell ingests a foreign bacterial cell, the vesicle fuses with this organelle. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(B) lysosome

The stiffest elements of the cytoskeleton, analogous to the bones of the human body, are (A) the cytosol. (B) microtubules. (C) intermediate filaments. (D) microfilaments.

(B) microtubules.

Phagocytosis is exemplified by __________. (A) a cell manufacturing a substance that is first enclosed in a vesicle and then later secreted from the cell (B) most types of white blood cells ingesting bacteria, viruses, and other foreign substances (C) a cell sampling a tiny amount of extracellular material (D) oxygen entering cells by diffusion (E) None of the listed responses is correct.

(B) most types of white blood cells ingesting bacteria, viruses, and other foreign substances

If a cell lacked peroxisomes, what vital process would NOT occur? (A) formation of soluble proteins for use in the cytosol (B) neutralization of free radicals (C) digestion of unwanted substances by enzymes, such as acid hydrolases (D) lipid metabolism and steroid synthesis (E) transport of vesicles

(B) neutralization of free radicals

Adenine, thymine, cytosine, and guanine are subunits of the DNA's double helix called __________. (A) telomeres (B) nucleotides (C) nucleosomes (D) histones (E) chromosomes

(B) nucleotides

Which of the following is associated with protein synthesis? (A) smooth endoplasmic reticulum (B) ribosomes (C) mitochondria (D) chloroplasts

(B) ribosomes

Ribosomes may be either free within the cytoplasm or bound to a membrane system known as the (A) Golgi apparatus. (B) rough endoplasmic reticulum. (C) cytoskeleton. (D) microtubule organizing center.

(B) rough endoplasmic reticulum.

Receptor-mediated endocytosis is the selective transport process that brings __________ into cells. (A) LDLs (low-density lipids), phagosomes, and clathrin (B) some viruses, hormones, and low-density lipids (LDLs) (C) water, enzymes, and fat-soluble molecules (D) white blood cells, insulin, and carbon dioxide (E) All of the listed responses are correct.

(B) some viruses, hormones, and low-density lipids (LDLs)

Embedded in the plasma membrane of cells, cholesterol molecules act to (A) participate in pinocytosis. (B) stabilize the membrane. (C) destabilize the membrane, leading to heart attacks. (D) make the membrane more resistant to freezing.

(B) stabilize the membrane.

The temporary structures in the cytoplasm include all of the following except (A) glycosomes. (B) the Golgi apparatus. (C) pigments. (D) lipid droplets.

(B) the Golgi apparatus.

The plasma membrane is composed of all of the following except (A) glycoproteins. (B) tubulin protein. (C) phospholipids. (D) cholesterol.

(B) tubulin protein.

Certain ethnic groups (like French Canadians) have an increased genetic predisposition for familial hypercholesterolemia (FH). If you are examining a 27-year-old French Canadian female who has chest pain consistent with a heart attack, which of the following would be the least useful? (A) Tests such as angiograms (X rays with dye that highlights changes in blood vessels) that would highlight atherosclerosis in the heart (coronary) arteries (B) Checking the patient's serum cholesterol levels (C) A chest X ray (D) A careful family history

(C) A chest X ray

Of the many mechanisms associated with aging, which is the best documented? (A) Mitochondria weaken and age the cells. (B) Antioxidants, such as Vitamins C and E, damage cells and cellular functions. (C) Free radicals build up and progressively damage essential cell molecules. (D) All aging is programmed into our genes.

(C) Free radicals build up and progressively damage essential cell molecules.

Which organelle works with the rough ER to package and ship new proteins to appropriate sites within the cell or for sectioning out of the cell? (A) Ribosomes (B) Mitochondria (C) Golgi apparatus (D) smooth endoplasmic reticulum

(C) Golgi apparatus

Which of the following statements about the rough endoplasmic reticulum is false? (A) It consists of stacked envelopes called cisternae. (B) It makes the digestive enzymes contained in the lysosomes. (C) It stores lipids as inclusions. (D) It makes the integral proteins of the cell membrane.

(C) It stores lipids as inclusions.

Which type of proteins are required for exocytosis? (A) clathrin (B) coatomer proteins (C) SNARE proteins (D) caveolin

(C) SNARE proteins

A phagosome is best described as __________. (A) a protein that is firmly embedded in or strongly attached to the lipid bilayer (B) an enzyme that detoxifies a number of toxic substances through the action of catalase, an enzyme that breaks down hydrogen peroxide (C) a membranous vesicle formed when pseudopods extend from the plasma membrane to enclose a clump of bacteria or cellular debris (D) the ring of contractile proteins (actin and myosin) that form in the center of a dividing cell that constricts to cleave the cell into two new cells

(C) a membranous vesicle formed when pseudopods extend from the plasma membrane to enclose a clump of bacteria or cellular debris

Which of the following is an inclusion, not an organelle? (A) microtubule (B) mitochondrion (C) glycosome (D) lysosome

(C) glycosome

Which of the listed organelles are not bound by a membrane or membranes? (A) Golgi apparatus and mitochondria (B) microtubules and lysosomes (C) intermediate filaments and ribosomes (D) smooth ER and microfilaments

(C) intermediate filaments and ribosomes

The cytoskeletal elements that are analogous to the muscles of the body which generate pseudopodia and contractile forces in conjunction with myosin are (A) microtubules. (B) intermediate filaments. (C) microfilaments. (D) integral proteins.

(C) microfilaments.

Which of the following cytoskeleton elements are the largest in diameter? (A) intermediate filaments (B) microfilaments (C) microtubules (D) centrioles

(C) microtubules

The endocytotic process in which small vesicles of fluid are brought into the cell is called (A) exocytosis. (B) phagocytosis. (C) pinocytosis. (D) xenocytosis.

(C) pinocytosis.

Which type of endocytosis ingests the most specific type of molecule? (A) fluid-phase endocytosis (B) pinocytosis (C) receptor-mediated endocytosis (D) phagocytosis

(C) receptor-mediated endocytosis

Fibroblasts produce the protein fibers found in many connective tissues. Many epithelial cells produce protein products that are secreted (mucus, enzymes, hormones). Which cellular organelles are abundant in these types of cells? (A) smooth ER (B) lysosomes (C) rough ER (D) Golgi apparatus

(C) rough ER

Cisternae of this organelle are continuous with the nuclear envelope. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(C) rough endoplasmic reticulum

This membranous organelle is the site of protein synthesis for proteins that are secreted by the cell. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(C) rough endoplasmic reticulum

Which membranous organelle stores calcium and is a primary site of lipid metabolism? (A) Golgi apparatus (B) mitochondrion (C) smooth endoplasmic reticulum (D) peroxisome

(C) smooth endoplasmic reticulum

Functions of the Golgi apparatus include all of the following except (A) synthesis of lysosomes. (B) plasma membrane formation. (C) production of secretory granules. (D) DNA replication.

(D) DNA replication.

Nuclear pores allow the transport of __________ molecules from the nucleus. (A)protein (B) DNA (C) Glycogen (D) RNA

(D) RNA

Which of the following does not pass through nuclear pores? (A) messenger RNA (B) proteins (C) ribosomal RNA (D) chromatin

(D) chromatin

Membrane-bound organelles have the same type of membrane as the plasma membrane except (A) they are all covered with ribosomes. (B) the nonpolar tails face outward. (C) for the absence of cholesterol. (D) for the absence of a glycocalyx.

(D) for the absence of a glycocalyx.

The nuclear envelope is continuous with the rough ER, but it differs from the rough ER in that it (A) is not associated with ribosomes. (B) consists of tubes, like the smooth ER. (C) consists of two membranes separated by a space. (D) has unique pores.

(D) has unique pores.

This organelle contains a single DNA molecule and is capable of self-replication. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(D) mitochondria

This organelle is characterized by folded membranes called cristae. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(D) mitochondria

This organelle is involved in production of cellular energy. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(D) mitochondria

This organelle produces ATP molecules. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(D) mitochondria

Of the following, the only organelle that has a double membrane structure is the (A) Golgi apparatus. (B) endoplasmic reticulum. (C) centriole. (D) mitochondrion.

(D) mitochondrion.

Which organelle is important in neutralizing free radicals? (A) mitochondrion (B) Golgi apparatus (C) lysosome (D) peroxisome

(D) peroxisome

Extended chromatin is where DNA's genetic code is copied onto messenger RNA molecules in a process called __________. (A) inversion (B) transconfiguration (C) translation (D) transcription (E) autolysis

(D) transcription

__________ constitute(s) the "assembly line" of the manufacturing plant. (A) Golgi apparatus (B) Peroxisomes (C) Mitochondria (D) Microtubules (E) Ribosomes (F) Smooth ER

(E) Ribosomes

This membranous organelle contains oxidase and catalase enzymes. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(E) peroxisome

This organelle detoxifies a number of toxic substances. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(E) peroxisome

This organelle is numerous in liver and kidney cells. (A) Golgi apparatus (B) lysosome (C) rough endoplasmic reticulum (D) mitochondria (E) peroxisome

(E) peroxisome

The role of the smooth endoplasmic reticulum is to __________. (A) manufacture ribosomal subunits (B) manufacture proteins for intracellular and extracellular functions (C) pull organelles along through the cytoplasm (D) fuse with phagosomes; empty their own enzymes into vesicles and digest their contents (E) produce steroid hormones and aid in drug detoxification

(E) produce steroid hormones and aid in drug detoxification

The importance of integral proteins is that they __________. (A) help support the membrane from its cytoplasmic side (B) make up about half of the plasma membrane by weight (C) provide a network within the cytoplasm, like an internal skeleton (D) are weakly embedded within the plasma membrane to allow detachment (E) provide attachment sites for short chains of carbohydrate molecules

(E) provide attachment sites for short chains of carbohydrate molecules

All of the following are true of mitochondria EXCEPT __________. (A) they are enclosed by two membranes (B) they are thought to have arisen from bacteria (C) they contain maternally inherited DNA (D) they generate ATP (E) they have the most free radicals of any organelle (F) they provide the instructions for protein synthesis

(F) they provide the instructions for protein synthesis

Hormones are secreted by (A) osmosis. (B) exocytosis. (C) phagocytosis. (D) pinocytosis.

B) exocytosis.

__________ is the substance that makes the plasma membrane more rigid and less permeable to water and water-soluble molecules.

Cholesterol

The inner membrane of a mitochondrion folds inward to produce shelf-like structures called __________.

Cristae

v-SNARES and t-SNARES bind together causing the lipid layers of both membranes to join, inserting vesicle membranes into plasma membranes in a process called __________.

Exocytosis

Chromatin is composed of DNA wound around proteins known as actin. True False

False

Extended chromatin is tightly wound around histones. True False

False

Microtubules are composed of actin. True False

False

Ribosomes consist of two subunits, each surrounded by a membrane. True False

False

The smooth ER contains its own molecules of DNA. True False

False

Which membrane structure is used for moving water-soluble molecules across the cell membrane?

Integral proteins

__________ are membranous sacs containing acid hydrolases and are sites of intracellular digestion.

Lysosomes

Cells that gather information and control body functions are __________.

Nerve cells

What are the macromolecules that form the two layers of the plasma membrane?

Phosophlipids

__________ is an enzyme that prevents telomeres from degrading by adding more repeating DNA to the ends.

Telomerase

__________ are repeating, nonsensical stretches of DNA that cap the ends of chromosomes.

Telomeres

The assembly of proteins from amino acids by ribosomes is called __________.

Translation

Hypercholesterolemia is an inherited disease in which the body's cells lack the protein receptors that bind to cholesterol-delivering LDLs. True False

True

Peroxisomes are important in detoxification of a number of toxic substances, for instance, hydrogen peroxide. True False

True

The nucleolus serves as the cell's ribosome-producing machine. True False

True