ch. 5 learning curve

During osmosis, water moves from a region of ______ to a region of ______.

"high solvent concentration; low solvent concentration" AND "low solute concentration; high solute concentration"

How many membranes make up a chloroplast?

3

What would be the outcome if the pump protein (shown in Fig. 5.13a) instead acted as a carrier that allowed protons to move from the extracellular fluid into the cytoplasm? a. ATP could be synthesized from ADP + Pi and the number of protons on either side of the membrane would equalize. b. The number of protons on either side of the membrane would equalize. c. The proton electrochemical gradient would be reversed. d. ATP could be synthesized from ADP + Pi.

a. ATP could be synthesized from ADP + Pi and the number of protons on either side of the membrane would equalize.

How do eukaryotic plant and animal cells differ from one another? a. Animal cells do not have chloroplasts and cell walls, and plant cells do. b. Animal cells have endoplasmic reticulum and plant cells don't. c. Animal cells have mitochondria but not chloroplasts, and plant cells have chloroplasts but not mitochondria. d. Animal cells have a plasma membrane and plant cells have a cell wall.

a. Animal cells do not have chloroplasts and cell walls, and plant cells do.

Prokaryotes absorb their nutrients from the environment; however, prokaryotes also have cell walls. What can you conclude from these statements? a. Cell walls are permeable, allowing nutrients to pass through. b. Prokaryotic cell walls do not allow nutrients to pass through them. c. Prokaryotes live in a hypertonic environment. d. Osmosis drives the movement of nutrients through the cell wall.

a. Cell walls are permeable, allowing nutrients to pass through.

Some lipid rafts are characterized by an accumulation of cholesterol. What does this mean for the fluidity of the raft domain? a. These lipid rafts are less fluid than the surrounding membrane at normal temperatures. b. These lipid rafts are more fluid than the surrounding membrane at normal temperatures. c. These lipid rafts are equally fluid as the surrounding membrane independent of temperature. d. These lipid rafts are less fluid than the surrounding membrane at low temperatures.

a. These lipid rafts are less fluid than the surrounding membrane at normal temperatures.

If cells had single-layer membranes like micelles, how would the structures of transmembrane proteins be affected? a. Transmembrane proteins would possess a hydrophobic region in the cell interior and a hydrophilic region in the extracellular space. b. Transmembrane proteins would only possess hydrophobic regions. c. Transmembrane proteins would only possess hydrophilic regions. d. The structures of transmembrane proteins would remain the same as if cells had lipid bilayers. e. Transmembrane proteins would possess a hydrophilic region in the cell interior and a hydrophobic region in the extracellular space.

a. Transmembrane proteins would possess a hydrophobic region in the cell interior and a hydrophilic region in the extracellular space.

All of the following are properties of at least some prokaryotic cells except: a. a nucleus. b. plasmids. c. small size. d. pili.

a. a nucleus

Which of the following would not be synthesized on the endoplasmic reticulum? a. cytoskeletal proteins b. pump proteins c. lipids d. lysosomal proteins

a. cytoskeletal proteins

All cells have: a. genetic information. b. a nucleus. c. internal compartments. d. a cell wall.

a. genetic information.

Which of the following eukaryotic cell structures plays a role in protein trafficking and sorting? a. the Golgi apparatus b. lysosomes c. mitochondria d. the endoplasmic reticulum e. vacuoles

a. the Golgi apparatus

Which part of a cholesterol molecule is polar? a. the OH group b. both the four interconnected planar rings and the hydrocarbon tail c. the four interconnected planar rings d. the hydrocarbon tail

a. the OH group

Predict how phospholipids arrange themselves when they are placed in a nonpolar solution. a. The phospholipid heads would orient toward the solution. b. The phospholipid tails would orient toward the solution. c. The phospholipids would form a bilayer. d. The phospholipid would form a liposome.

b. . The phospholipid tails would orient toward the solution.

What type of molecule is not associated with a cell's plasma membrane? a. phospholipid b. RNA c. protein d. carbohydrate

b. RNA

Bacteria are rarely larger than 1-2 μm in size, and are typically shaped like rods, spheres, or spirals. What likely accounts for the shape and size of these prokaryotes? a. Such shapes likely make it difficult for predators to catch bacteria. b. Such shapes maximize the surface area over which nutrients can diffuse into bacteria. c. Such shapes can accommodate the complex arrangements of plasmids within bacteria. d. Such shapes facilitate the formation of pili in bacteria. e. Such shapes both facilitate the formation of pili in bacteria and maximize the surface area over which nutrients can diffuse into bacteria.

b. Such shapes maximize the surface area over which nutrients can diffuse into bacteria.

A researcher is very surprised to find a prokaryotic cell that is greater than 100 μm in diameter. How could this be possible? a. A mutation has occurred that increases the size of the nucleoid by two, thereby allowing the cell to grow in diameter. b. There may be a large vacuole in the cell, which allows nutrients to still reach all areas of the cytoplasm in the cell. c. Plasmids within the cell carry mutations that allow the cell to grow larger in size. d. Through pili interactions, the prokaryotic cell can grow larger in size. e. A mutation has increased the size of the nucleoid by two, or the prokaryote can grow larger in size through pili interactions.

b. There may be a large vacuole in the cell, which allows nutrients to still reach all areas of the cytoplasm in the cell.

A cell's plasma membrane contributes to homeostasis by: a.defining the boundary between the inside and outside of the cell. b. acting as a selective barrier. c. maintaining the shape of the cell. d. functioning as a fluid mosaic of lipid and protein.

b. acting as a selective barrier.

A nuclear pore is most similar to a: a. carrier protein. b. channel protein. c. pump protein. d. symporter protein.

b. channel protein.

Which of the following molecules does not easily diffuse across a plasma membrane? a. small polar molecules b. large polar molecules c. gases d. both small and large polar molecules

b. large polar molecules

Which eukaryotic organelle is associated with the breakdown of macromolecules? a. endoplasmic reticulum b. lysosome c. mitochondria d. the Golgi apparatus

b. lysosome

Match the organelle with its description. Responses may be used multiple times or not at all. (Type in the letters representing your answers in the below box. No spaces or commas are needed in between answers.) a. endoplasmic reticulum b. Golgi apparatus c. nuclear envelope ____ involved in the sorting of lipids and proteins ____ composed of two membranes ____ composed of multiple cisternae ____ involved in the synthesis of lipids and proteins ____ connected to the endoplasmic reticulum

bcbac

Based on what you know regarding mitochondria, which of the following most likely depicts the chemical reaction for cellular respiration? a. C6H12O6 (sugar) → 6CO2 (carbon dioxide) + 6H2O (water) b. C6H12O6 (sugar) + 6O2 (oxygen) → 6CO2 (carbon dioxide) c. C6H12O6 (sugar) + 6O2 (oxygen) → 6CO2 (carbon dioxide) + 6H2O (water) d. 6CO2 (carbon dioxide) + 6H2O (water) → C6H12O6 (sugar) + 6O2 (oxygen) e. 6CO2 (carbon dioxide) + 6H2O (water) → 6O2 (oxygen)

c. C6H12O6 (sugar) + 6O2 (oxygen) → 6CO2 (carbon dioxide) + 6H2O (water)

How is a carrier protein different from a channel protein? a. Transport through a carrier does not depend on the random motion of molecules. b. Transport through carrier proteins depends on concentration gradients, but transport through channel proteins does not. c. Carrier proteins undergo conformational change so that they are open alternately to one side of the membrane or the other. d. Carrier proteins use ATP, but channel proteins do not.

c. Carrier proteins undergo conformational change so that they are open alternately to one side of the membrane or the other.

How is the energy stored in a molecule of ATP used by the sodium-potassium pump? a. It is used to transport potassium ions out of the cell. b. It is used to transport sodium ions into the cell. c. It is used to alter the conformation of the pump protein. d. All of these choices are correct.

c. It is used to alter the conformation of the pump protein.

If a cell lacked a cytoskeleton, which of the following would likely be a result? a. The cell would be unable to carry out translation. b. The cell would be unable to harness energy. c. The shape of the cell would be affected and protein movement in the cell would be affected. d. Protein movement in the cell would be affected. e. The shape of the cell would be impacted.

c. The shape of the cell would be affected and protein movement in the cell would be affected.

An amphipathic molecule is one that: a. has a head and tail domain. b. can fully dissolve in water. c. contains both polar and nonpolar regions. d. makes up a membrane.

c. contains both polar and nonpolar regions.

What accounts for the ability of vesicles to fuse with different membrane compartments in the cell? a. the cell's cytoskeleton b. peripheral membrane proteins c. the fluid nature of the phospholipid bilayer d. transport proteins

c. the fluid nature of the phospholipid bilayer

How is a micelle different from a liposome? a. A micelle is composed of a single layer of phospholipids. b. Micelle phospholipids have bulky head groups. c. Micelle phospholipids have a single fatty acid tail. d. All of these choices are correct.

d. All of these choices are correct.

What factors are required for net movement of a substance to occur by facilitated diffusion? a. a concentration gradient b. a plasma membrane c. a transport protein d. All of these choices are correct.

d. All of these choices are correct.

A proton pump is needed in the lysosomal membrane because: a. the interior of the lysosome needs to be acidic. b. protons are being moved from low to high concentration. c. protons cannot move across a membrane on their own. d. All of these choices are correct.

d. all are correct

Where are ribosomes found inside a cell? a. in the cytosol b. attached to the rough endoplasmic reticulum c. attached to the Golgi apparatus d. both in the cytosol and attached to the rough endoplasmic reticulum

d. both in the cytosol and attached to the rough endoplasmic reticulum

The genetic material of a prokaryotic cell is located in its: a. nucleus. b. nucleosome. c. nucleolus. d. nucleoid.

d. nucleoid.

The process of diffusion requires: a. a concentration gradient. b. ATP. c. transport proteins. d. the random movement of molecules.

d. the random movement of molecules.

Which of the following statements is true regarding cytosol? a. Cytosol excludes organelles. b. Cytosol is the "jelly" substance within cells. c. Cytosol contains, and includes, organelles. d. Cytosol includes the nucleus. e. Cytosol is the "jelly" substance within cells and it excludes organelles.

e. Cytosol is the "jelly" substance within cells and it excludes organelles.

Imagine a cell that has a membrane composed mostly of lipids with saturated fatty acid tails, and that this membrane also has low cholesterol content. What are the characteristics of this cell membrane? a. The lipids would be able to easily transition between the inner and outer layers of the bilayer constituting the cell membrane. b. The lipids contained in such a membrane would be highly mobile, and in near constant flux. c. Due to its cholesterol content, the cell membrane would remain fluid even at cold temperatures. d. The characteristics of this cell membrane will closely mirror those of a membrane composed of only unsaturated fatty acids. e. None of the other answer options is correct.

e. None of the other answer options is correct.

A bacterial cell, a plant cell, and an animal cell have which of the following structures in common? a. nucleus b. vacuole c. cell wall d. nucleoid e. cytoplasm

e. cytoplasm

Given that both plant and animal cells have mitochondria, chloroplasts are actually unnecessary in plant cells. T of ?

false

A protein that is temporarily associated with a biological membrane is a(n):

peripheral membrane protein

Mitochondria use _____ and _____ to generate ATP for use by the cell.

pyruvate derived from sugar; oxygen

Mitochondria and chloroplasts both have inner and outer membranes. T or F?

true