Mastering Biology 2

Which statement correctly characterizes bound ribosomes? a) The most common location for bound ribosomes is the cytoplasmic surface of the plasma membrane. b) Bound ribosomes generally synthesize membrane proteins and secretory proteins. c) Bound ribosomes are enclosed in their own membrane. d) Bound and free ribosomes are structurally different. e) All of the above.

b) Bound ribosomes generally synthesize membrane proteins and secretory proteins

Cells of the pancreas will incorporate radioactively labeled amino acids into proteins. This "tagging" of newly synthesized proteins enables a researcher to track their location. In this case, we are tracking an enzyme secreted by pancreatic cells. What is its most likely pathway? a) ER -> lysosomes -> vesicles that fuse with plasma membrane b) Golgi -> ER -> lysosomes c) ER -> Golgi -> vesicles that fuse with plasma membrane d) ER -> Golgi -> nucleus e) nucleus -> ER -> Golgi

c) ER -> Golgi -> vesicles that fuse with plasma membrane

Which of the following is present in a prokaryotic cell? a) mitochondrion b) nuclear envelope c) ER d) chloroplast e) ribosome

e) ribosome

Which cell structures are found only in animal cells?

-centriole

Which cell structures are found only in plant cells?

-chloroplasts -cellulose cell wall -central vacuole

Which cell structures are found in both plant and animal cells?

-mitochondria -endoplasmic reticulum -Golgi apparatus -cytoskeleton -nucleus -plasma membrane

Which of the following is a characteristic feature of a carrier protein in a plasma membrane? a) It exhibits a specificity for a particular type of molecule. b) It works against diffusion. c) It has few, if any, hydrophobic amino acids. d) It requires the expenditure of cellular energy to function. e) It is a peripheral membrane protein.

a) It exhibits a specificity for a particular type of molecule

According to the fluid mosaic model of cell membranes, which of the following is a true statement about membrane phospholipids? a) They can move laterally along the plane of the membrane. b) They have hydrophilic tails in the interior of the membrane. c) They occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane. d) They frequently flip-flop from one side of the membrane to the other. e) They are free to depart from the membrane and dissolve in the surrounding solution.

a) They can move laterally along the plane of the membrane.

Which statements are true for chloroplasts? a) They contain the green pigment chlorophyll. b) They are the sites of reactions that convert solar energy into chemical energy. c) Their inner membrane has infoldings called cristae. d) Their matrix contains enzymes that function in cellular respiration. e) They are the sites of reactions that convert chemical energy to ATP. f) They have membranous sacs called thylakoids that are surrounded by a fluid called stroma.

a) They contain the green pigment chlorophyll. b) They are the sites of reactions that convert solar energy into chemical energy. f) They have membranous sacs called thylakoids that are surrounded by a fluid called stroma.

Cells can be described as having a cytoskeleton of internal structures that contribute to the shape, organization, and movement of the cell. Which of the following are part of the cytoskeleton? a) microfilaments b) the nuclear envelope c) nucleoli d) mitochondria e) lysosomes

a) microfilaments

Which structure-function pair is mismatched? a) microtubule; muscle contraction b) lysosome; intracellular digestion c) Golgi; protein trafficking d) nucleolus; production of ribosomal subunits e) ribosome; protein synthesis

a) microtubule; muscle contraction

Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids? a) smooth endoplasmic reticulum b) contractile vacuole c) mitochondrion d) ribosome e) lysosome

a) smooth endoplasmic reticulum

Which of these is NOT a lipid? a) RNA b) phospholipid c) steroids d) cholesterol e) wax

b) RNA

Which of the following descriptions best fits the class of molecules known as nucleotides? a) a nitrogenous base and a phosphate group b) a nitrogenous base, a phosphate group, and a pentose sugar c) a nitrogenous base and a pentose sugar d) a pentose sugar and a purine or pyrimidine e) a phosphate group and an adenine or uracil

b) a nitrogenous base, a phosphate group, and a pentose sugar

Proteins are polymers of _____. a) glycerol b) amino acids c) nucleotides d) CH2O units e) hydrocarbons

b) amino acids

There are 20 different amino acids. What makes one amino acid different from another? a) different alpha carbons b) different side chains (R groups) attached to an alpha carbon c) different asymmetric carbons d) different amino groups attached to an alpha carbon e) different carboxyl groups attached to an alpha carbon

b) different side chains (R groups) attached to an alpha carbon

Which of these is rich in unsaturated fats? a) beef fat b) olive oil c) lard d) a fat that is solid at room temperature e) butter

b) olive oil

What type of bond joins the monomers in a protein's primary structure? a) S - S b) peptide c) hydrogen d) ionic e) hydrophobic

b) peptide

Tertiary structure is NOT directly dependent on _____. a) bonds between sulfur atoms b) peptide bonds c) hydrophobic interactions d) ionic bonds e) hydrogen bonds

b) peptide bonds

Which of the following types of molecules are the major structural components of the cell membrane? a) nucleic acids and proteins b) phospholipids and proteins c) proteins and cellulose d) glycoproteins and cholesterol e) phospholipids and cellulose

b) phospholipids and proteins

Which of the following is a compartment that often takes up much of the volume of a plant cell? a) peroxisome b) vacuole c) lysosome d) mitochondrion e) Golgi apparatus

b) vacuole

Why isn't the mitochondrion classified as part of the endomembrane system? a) It is not involved in protein synthesis. b) It has too many vesicles. c) Its structure is not derived from the ER. d) It is not attached to the outer nuclear envelope. e) It only has two membrane layers.

c) Its structure is not derived from the ER

A function of cholesterol that does not harm health is its role _____. a) All of cholesterol's effects cause the body harm. b) the most abundant male sex hormone c) as a component of animal cell membranes d) in calcium and phosphate metabolism e) as the primary female sex hormone

c) as a component of animal cell membranes

According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly a) randomly oriented in the membrane, with no fixed inside-outside polarity. b) free to depart from the fluid membrane and dissolve in the surrounding solution. c) embedded in a lipid bilayer. d) confined to the hydrophobic core of the membrane. e) spread in a continuous layer over the inner and outer surfaces of the membrane.

c) embedded in a lipid bilayer

Which structure is common to plant and animal cells? a) centriole b) wall made of cellulose c) mitochondrion d) chloroplast e) central vacuole

c) mitochondrion

Which structure is the site of the synthesis of proteins that may be exported from the cell? a) plasmodesmata b) Golgi vesicles c) rough ER d) tight junctions e) lysosomes

c) rough ER

The bonding of two amino acid molecules to form a larger molecule requires a) both the release of a carbon dioxide molecule and the addition of a nitrogen atom. b) the release of a carbon dioxide molecule. c) the release of a water molecule. d) the addition of a water molecule. e) the addition of a nitrogen atom.

c) the release of a water molecule

Which of the following statements best summarizes the structural differences between DNA and RNA? a) RNA is a protein, whereas DNA is a nucleic acid. b) DNA is a protein, whereas RNA is a nucleic acid. c) RNA is a double helix, but DNA is single-stranded. d) DNA nucleotides contain a different sugar than RNA nucleotides. e) RNA is a protein, whereas DNA is a nucleic acid; and RNA is a double helix, but DNA is single-stranded.

d) DNA nucleotides contain a different sugar than RNA nucleotides.

The secondary structure of a protein results from _____. a) hydrophobic interactions b) bonds between sulfur atoms c) peptide bonds d) hydrogen bonds e) ionic bonds

d) hydrogen bonds

Which type of interaction stabilizes the alpha helix and the beta pleated sheet structures of proteins? a) nonpolar covalent bonds b) hydrophobic interactions c) peptide bonds d) hydrogen bonds e) ionic bonds

d) hydrogen bonds

What kinds of molecules pass through a cell membrane most easily? a) ionic b) large and hydrophobic c) monosaccharides such as glucose d) small and hydrophobic e) large polar

d) small and hydrophobic

Which of the following are capable of converting light energy to chemical energy? a) Golgi bodies b) peroxisomes c) mitochondria d) leucoplasts e) chloroplasts

e) chloroplasts

The cilia and flagella of eukaryotic cells are composed of _____. a) pili b) tonofilaments c) microfilaments d) intermediate filaments e) microtubules

e) microtubules

Organelles other than the nucleus that contain DNA include a) ribosomes, mitochondria, and chloroplasts b) ribosomes. c) chloroplasts. d) mitochondria. e) mitochondria and chloroplasts only

e) mitochondria and chloroplasts only

When a plant cell, such as one from a peony stem, is submerged in a very hypotonic solution, what is likely to occur? a) the cell will become flaccid b) the cell membrane will lyse c) plasmolysis will shrink the interior d) the cell will burst e) the cell will become turgid

e) the cell will become turgid