amen

The internal solute concentration of a plant cell is about 0.8 M. To demonstrate plasmolysis, it would be necessary to suspend the cell in what solution?

1.0 M

10) Which structure is the site of the synthesis of proteins that may be exported from the cell? A) rough ER B) lysosomes C) plasmodesmata D) Golgi vesicles E) free cytoplasmic ribosomes

A) rough ER

41) Proteins coded for by nuclear DNA but found within mitochondria move from the cytoplasm into mitochondria using ________. A) signal sequences (peptides) B) random transport vesicles C) attachment of ribosomes to outer mitochondrial pores and direct deposition into the inner mitochondrial compartment D) mRNAs that are manufactured in the nucleus but translated by mitochondrial ribosomes

A) signal sequences (peptides)

52) Cells require which of the following to form cilia or flagella? A) tubulin B) laminin C) actin D) intermediate filaments E) secretory vesicles

A) tubulin

Secondary active transport

AKA cotransport. When this occurs, a gradient set up by pump provides the energy needed to power the movement of a different molecule against its particular gradient

Active and passive transport of solutes across a membrane typically differ in which of the following ways?

Active transport always involves the utilization of cellular energy, whereas passive transport does not require cellular energy.

Pump

Active transport protein. when phosphate group binds to it, the phosphates negative charge interacts with the charged amino acid residues in the protein, causing the proteins potential energy to increase and change its shape

Which of the following is a correct difference between active transport and facilitated diffusion?

Active transport requires energy from ATP, and facilitated diffusion does not.

Which line in the graph represents the bag that contained a solution isotonic to the 0.6 M solution at the beginning of the experiment?

C

Which of the following contains its own DNA and ribosomes? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

C

Which of the following contains its own DNA and ribosomes?A) lysosomeB) vacuoleC) mitochondrionD) Golgi apparatusE) peroxisome

C

Which of the following statements about the cytoskeleton is true? A) The dynamic aspect of cytoskeletal function is made possible by the assembly and disassembly of a large number of complex proteins into larger aggregates. B) Microfilaments are structurally rigid and resist compression, while microtubules resist tension (stretching). C) Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other. D) Chemicals that block the assembly of the cytoskeleton would cause little effect on the cellʹs metabolism E) Transport vesicles among the membranes of the endomembrane system produce the cytoskeleton.

C

30%

How much % of all ATP in the body is used to drive the Na+/K+-ATPase cycle

If a red blood cell is placed in a salt solution and bursts, what is the tonicity of the solution relative to the interior of the cell?

Hypotonic

The Lipid-dervived second messenger _______________ diffuses to receptors on the smooth ER, thereby opening gates that releases _____________ ions, which drives exocytosis of chemicals stored in _____________ vessicles.

IP3, calcium, secretory

The lipid derived second messengers produced by the activation of the enzyme Phospholipase C by the activted beta-gamma G protein complekx are the soluble second messenger ___________ and the membrane bound second messenger _____________ .

IP3.....DAG

Ion channels

Ions often cross membranes through special membrane proteins called ___ ____. These form openings in a membrane. Ions almost never cross pure lipid bilayers by themselves

what cannot rapidly pass directly through the phospholipids of a plasma membrane

Ions, such as hydrogen ions, and hydrophilic molecules, such as water and glucose

A selectively permeable membrane separates two solutions. Water is able to pass through this membrane; however, sucrose (a disaccharide) and glucose (a monosaccharide) cannot pass. The membrane separates a 0.2-molar sucrose solution from a 0.2-molar glucose solution. With time, how will the solutions change?

Nothing will happen, because the two solutions are isotonic to one another.

In a plant cell, DNA may be found where?

Nucleus, mitochondria, and chloroplast.

The liver is involved in detoxification of many poisons and drugs. What structure is primarily involved in this process and, therefore, abundant in liver cells?

Smooth ER.

Which of the following transporters does not use passive transport to move molecules across a membrane?

Sodium-potassium pump

Drag the labels to their appropriate locations in the figure. First, drag labels to targets (a) and (b) to indicate whether these environments are hydrophilic or hydrophobic. Next, drag the phospholipid layers to targets (c) and (d) to indicate how they are oriented in the plasma membrane. Finally, drag labels to targets (e), (f), and (g) to indicate which portions of the membrane protein are hydrophilic and which are hydrophobic.

a. hydrophilic b. hydrophobic c. tail face down d. tail face up e. hydrophilic f. hydrophobic g. hydrophilic

Drag the labels to fill in the table. Use only white labels for white targets, pink labels for pink targets, and blue labels for blue targets.

a. hydrophobic b. can cross easily c. no transport protein required d. hydrophilic e. have difficulty crossing the hydrophobic part f. transport protein required to cross efficiently g. hydrophilic h. have difficulty crossing the hydrophobic part i. transport protein required to cross efficiently

Basal bodies are most closely associated with which of the following cell components?

cilia

If the protrusions are short and numerous they are termed what?

cilia

The most abundant protein found in the extracellular matrix of animal cells is _______.

collagen

Long fibers of protein found in the extracellular matrix that provide structural support for cells. -Choose one: Cellulose, plasmodesmata, collagen, gap junctions, or tight junctions -Choose one: animal or plant

collagen, animal

A cell junction found in the connection between skeletal muscle cells and that keep them from ripping apart duing contraction would most likely be _______

desmosomes

The primary role of _____ is to bind animal cells together.

desmosomes

What junction is this-anchoring juction-fasten cells together in strong sheets

desmosomes

Membrane protein complexes that strengthen the adhesion between adjacent cells, like rivets, to protect against pulling forces. -Choose one: Cellulose, plasmodesmata, collagen, gap junctions, or tight junctions -Choose one: animal or plant

desmosomes, animal

What name is given to the process shown in this animation?

diffusion

osmosis

diffusion of water across the plasma membrane from areas of high concentration to areas of lower concentration

Cooking oil and gasoline (a hydrocarbon) are not amphipathic molecules because they _____.

do not have a polar or charged region

Diffusion is the movement of particles

down their concentration gradient

The Golgi apparatus has a polarity or sidedness to its structure and function. Which of the following statements correctly describes this polarity?A) Transport vesicles fuse with one side of the Golgi and leave from the opposite side.B) Proteins in the membrane of the Golgi may be sorted and modified as they move fromone side of the Golgi to the other.C) Lipids in the membrane of the Golgi may be sorted and modified as they move fromone side of the Golgi to the other.D) Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified asthey move from one side of the Golgi to the other.E) All of the above correctly describe polar characteristics of the Golgi function.

e

What is NOT part of a Prokaryotic cell? a.ribosomes b.DNA c.a cell wall d.a plasma membranee.an endoplasmic reticulum

e.an endoplasmic reticulum

According to the fluid mosaic model of membrane structure, proteins of the membrane are mostly

embedded in a lipid bilayer.

Consider a protein that is made in the rough endoplasmic reticulum. You observe that when the synthesis of the protein is completed, the protein is located in the ER membrane. Where else in the cell might this protein be found?

embedded in the plasma membrane functioning in the transport of molecules into the cell

The plasma membrane forms a pocket that pinches inward, forming a vesicle that contains material from outside the cell. This describes the process of

endocytosis.

Calcium ions that act as second messengers are stored in _____.

endoplasmic reticula

Which of the following is NOT a function of membrane proteins?

energy, carbon, and nitrogen storage

stroma

enzyme fluid within a chloroplast, site of light independent reaction

Which of these extracellular signal molecules could diffuse through a plasma membrane and bind to an intracellular receptor? -glycerol -starch -glucose -cellulose -estrogen

estrogen

Click on the vesicle to start the animation. This is an animation of _____.

exocytosis

Some large molecules move into or out of cells by exocytosis or endocytosis.

exocytosis endocytosis

Can you match the processes involved in membrane transport to their descriptions?

exocytosis facilitated diffusion endocytossis diffusion active transport

Which of the following processes and organelles account for the replacement of lipids and proteins lost from the plasma membrane?

exocytosis and smooth ER and rough ER

The process shown in this animation is referred to as _____.

facilitated diffusion

A molecule moves down its concentration gradient using a transport protein in the plasma membrane. This is an example of

facilitated diffusion.

Which of the following is/are most likely to be involved in the process of producing proteins for a chloroplast or mitochondrion?

free cytoplasmic ribosomes

Which of the following organelles is unlikely to show enhanced abundance in pancreatic cells that secrete large amounts of digestive enzymes?

free cytoplasmic ribosomes

Cell junctions that allow direct cell to cell transfer of electrical or chemical signals are called:

gap junctions

What junction is this-communicating junction-provide cytoplasmic channels between adjacent cells

gap junctions

In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which organelle would this be?

lysosome

Which of the following contains hydrolytic enzymes? A) lysosomeB) vacuoleC) mitochondrionD) Golgi apparatusE) peroxisome

lysosome

A bacterium engulfed by a white blood cell through phagocytosis will be digested by enzymes contained in _____.

lysosomes

Which of the following categories best describes the function of the rough endoplasmic reticulum?

manufacturing

What is the definition of resolution?

measure of clarity of image, the measure of distinguishing two points that are very close to each other

thylakoid

membrane bound structure within the chloroplast, site of light dependent reaction

The voltage across a membrane is called the _____.

membrane potential

Which of the following structures is found in eukaryotic but not prokaryotic cells?

mitochondria

which is false?

mitochondria contain ribosomes in the intermembrane space

Which of the following five membranes is most likely to have a lipid composition that is distinct from the other four?

mitochondrial outer membrane

Which organelle is one of the main energy transformers of cells?

mitochondrion

Which structure is common to plant and animal cells?

mitochondrion

In active transport,

molecules move across the plasma membrane against their concentration gradient.

phospholipid

molecules that make up the inner bilayer of cell membranes. they have a polar hydrophilic head and a non-polar, hydrophobic tail.

Cilia and flagella move due to the interaction of the cytoskeleton with which of the following?

motor proteins

RNA is a

nucleic acid

A dish of animal cells was grown in the presence of radioactive phosphorous. The phosphorous largely ended up in nucleotides inside the actively growing animal cells. In which cellular structure(s) would you predict the majority of the radioactive phosphorous to accumulate?

nucleus

What are the components of the endomembrane system?

nucleus and nuclear envelope, endoplasmic reticulum, golgi apparatus, lysosomes, vacuoles, & plasma membrane

In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis?

on the inside surface of the vesicle

Consider the currently accepted fluid mosaic model of the plasma membrane. Where in the membrane would carbohydrates most likely be found?

on the outside (external) surface of the membrane

What are the main functions that Smooth ER does?

synthesizes lipids, metabolizes carbs, stores calcium, & detoxifies poison

Which of the following cell structures exhibits selective permeability between a cell and its external environment?

the plasma membrane

Which junction is this-membranes of neighboring cells are pressed together, preventing leakage of extracellular fluid.

tight junctions

Which of these cell junctions form a barrier to the passage of materials? -keratin fibers -gap (communicating) junctions -tight junctions -desmosomes (anchoring junctions) -plasmodesmata

tight junctions

Membrane proteins that create a watertight seal between cells. -Choose one: Cellulose, plasmodesmata, collagen, gap junctions, or tight junctions -Choose one: animal or plant

tight junctions, animal

Name the Intercellular junctions in animals.

tight junctions, desmosomes, and gap junctions

What is the role of the mitochondria?

to change energy from one form to another, the site of cellular respiration, in nearly all eukaryotic cells, has two membranes-smooth outer membrane & an inner membrane folded into cristae

What is the function of the cytoskeleton?

to organize the cell structures and activities and anchor many organelles, play a role in support, motility, and regulation of the cell, Also helps to maintain its shape.

In this animation, which of the following, when activated by a signal transduction pathway, moved from the cytoplasm to the nucleus of a cell?

transcription factor

Which of these is the second of the three stages of cell signaling? -gene activation -reception -binding of a neurotransmitter to a plasma membrane receptor -transduction -cell response

transduction

Lactose transport by membrane proteins occurs under conditions in which the concentration of lactose inside the cell is higher than the concentration outside the cell. What type of transport is used to move lactose into the cell?

transport

Structure A in this animation is a(n) _____.

transport protein

Structure B is a _____.

transport protein

Which of the following best describes the structure of a biological membrane?

two layers of phospholipids with proteins either crossing the layers or on the surface of the layers

Olive oil is a plant oil, and most plant oils are rich in

unsaturated fats

wax is made of

unsaturated long tail lipids

What organelle takes up much of the volume of a plant cell?

vacuole

What are the three types of vacuoles?

food, contractile, and central vacuoles

if a fatty acid chain lacks double bonds it is

saturated

Electrochemical gradient

Ions move in response to combo of concentration and electrical gradient, which is called?

Complete the diagram below using the following steps. Drag the correct white label to the white target, indicating how many ions move through the pump and in which directions. Drag the pink labels to the pink targets, indicating the relative concentrations of Na+ and K+ inside and outside the cell. Drag the blue labels to the blue targets, indicating the relative charges inside and outside the cell.

**Active transport by the sodium-potassium pump follows this cycle. The number one, corresponding to step one in a diagram below the text. Three Na+ ions from the cytosol bind to the pump. The number two, corresponding to step two in the diagram below the text. The binding of Na+ stimulates the phosphorylation of the pump protein by ATP. The number three, corresponding to step three in the diagram below the text. Phosphorylation causes a conformational change in the pump that moves the three Na+ ions against their concentration gradient and releases them outside the cell. The number four, corresponding to step four in the diagram below the text. The release of the Na+ ions permits two K+ ions from outside the cell to bind to the pump, and the phosphate group is released. The number five, corresponding to step five in the diagram below the text. Release of the phosphate group causes another conformational change in the pump. The number six, corresponding to step six in the diagram below the text. The conformational change in the pump moves the two K+ ions against their concentration gradient and releases them into the cytosol. A diagram showing six steps of active transport in the sodium-potassium pump. Each numbered step corresponds to the text above. The net result is that the concentration of Na+ is higher outside the cell and the concentration of K+ is higher inside the cell. In addition, one more positive charge has been transported out of the cell than into the cell, leaving the outside of the cell with an excess positive charge and the inside with an excess negative charge. Thus, the sodium-potassium pump creates both chemical gradients and charge differences across the plasma membrane. The function of the sodium-potassium pump in animal cells (and the proton pump in bacteria and plant cells) is essential to many cell functions. It prevents chemical and electrical gradients across the plasma membrane from reaching equilibrium (at which point the cell would be dead) and powers many types of active transport across the plasma membrane.

Sort the phrases into the appropriate bins depending on whether they are true only for channels, true only for carrier proteins, or true for both channels and carriers.

*Carrier proteins and channels are both transport proteins involved in facilitated diffusion, the passive transport of solutes across a membrane down their concentration or electrochemical gradient. As integral membrane proteins, both carriers and channels protect polar or charged solutes from coming into contact with the hydrophobic interior of the lipid bilayer. Furthermore, all transport proteins are specific for the solutes they transport, owing to the specificity of the interactions between the solute and the transport protein.

A red blood cell has been placed into three different solutions. One solution is isotonic to the cell, one solution is hypotonic to the cell, and one solution is hypertonic to the cell. Determine which type of solution is in each beaker based on the cell's reaction. Drag each item to the appropriate bin.

*For a cell in an isotonic solution, water flows into the cell to the same extent that it flows out of the cell. If a cell is in a hypotonic solution, water flows into the cell, which causes it to swell and potentially burst. For a cell in a hypertonic solution, water flows out of the cell, which causes it to shrink.

Sort the phrases into the appropriate bins depending on whether they describe exocytosis, endocytosis, or both.

*In exocytosis, substances are transported to the plasma membrane in vesicles derived from the endomembrane system. These vesicles fuse with the plasma membrane, releasing the enclosed substances outside the cell. In endocytosis, substances are taken into the cell by folding in of the plasma membrane and pinching off of the membrane to form a vesicle. Notice that in both exocytosis and endocytosis, the transported substances never actually cross the plasma membrane as they leave or enter the cell.

Which statements about the fluid mosaic structure of a membrane are correct? Select the three correct statements.

*Membranes consist of diverse proteins suspended in and attached to a phospholipid bilayer. Kinks in the unsaturated fatty acid tails of some phospholipids keep the membrane fluid, and a mosaic of proteins perform a variety of functions.

Which of the following molecules can cross the lipid bilayer of a membrane directly, without a transport protein or other mechanism? Select all that apply.

*Some solutes pass readily through the lipid bilayer of a cell membrane, whereas others pass through much more slowly, or not at all. Small nonpolar (hydrophobic) molecules, such as dissolved gases (O2, CO2, N2) and small lipids, can pass directly through the membrane. They do so by interacting directly with the hydrophobic interior of the lipid bilayer. Very small polar molecules such as water and glycerol can pass directly through the membrane, but much more slowly than small nonpolar molecules. The mechanism that permits small polar molecules to cross the hydrophobic interior of the lipid bilayer is not completely understood, but it must involve the molecules squeezing between the hydrophobic tails of the lipids that make up the bilayer. Polar molecules such as glucose and sucrose have very limited permeability. Large molecules such as proteins cannot pass through the lipid bilayer. Ions and charged molecules of any size are essentially impermeable to the lipid bilayer because they are much more soluble in water than in the interior of the membrane.

Which of the following statements correctly describe(s) the driving forces for diffusion of Na+ and K+ ions through their respective channels? Select all that apply.

*The concentration gradient of Na+ ions across the membrane (higher Na+ concentration outside) facilitates the diffusion of Na+ into the cell. At the same time, the electrical gradient across the membrane (excess positive charge outside) drives Na+ into the cell. The concentration gradient of K+ ions across the membrane (higher K+ concentration inside) facilitates the diffusion of K+ out of the cell. However, the electrical gradient across the membrane (excess positive charge outside) impedes the diffusion of K+ out of the cell. The electrochemical gradient for an ion is the sum of the concentration (chemical) gradient and the electrical gradient (charge difference) across the membrane. For Na+ ions, diffusion through the Na+ channel is driven by both the concentration gradient and the electrical gradient. But for K+ ions, the electrical gradient opposes the concentration gradient. Therefore, the electrochemical gradient for Na+ is greater than the electrochemical gradient for K+.

Histamine is a chemical substance released in inflammatory and allergic responses. The histamine H1 receptor on target cells is a G protein-coupled receptor that activates phospholipase C in response to the binding of histamine. Which statements are true about the binding of histamine to the histamine H1 receptor? Select all that apply. -Histamine diffuses across the plasma membrane to bind to the H1 receptor. -Histamine binds extracellularly to the H1 receptor. -When histamine binds to the H1 receptor, the receptor undergoes a conformation change and binds the inactive G protein. -Histamine binds intracellularly to the inactive G protein, activating the G protein. -Once the G protein is active, it binds to the enzyme phospholipase C, activating it. -Histamine is likely hydrophilic.

-Histamine binds extracellularly to the H1 receptor. -When histamine binds to the H1 receptor, the receptor undergoes a conformation change and binds the inactive G protein. -Once the G protein is active, it binds to the enzyme phospholipase C, activating it. -Histamine is likely hydrophilic.

Which of the following could account for the different cellular responses to histamine? Select all that apply. -the type of signaling molecule -the types of relay molecules within the cell -the enzyme that is activated by the G protein associated with the receptor -the type of second messengers involved in the signal transduction pathway -the cell type in which the histamine receptor is located

-the types of relay molecules within the cell -the enzyme that is activated by the G protein associated with the receptor -the type of second messengers involved in the signal transduction pathway -the cell type in which the histamine receptor is located

Look at diagrams in cell junctions, ECM, and CAMs

....

Look at diagrams on Long distance cell-cell communication

....

an isotonic solution has what percentage of NaCl

0.9% (m/v) NaCl

Which component is a microfilament (actin filament) of the cytoskeleton?

C

an isotonic solution has what percentage of glucose

5.0% (m/v) glucose

What concentration of radioactive glucose did the researchers find in the red blood cells of a 15-day-old guinea pig after an incubation time of 30 minutes?

85 mM

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) the nuclear envelope B) mitochondria C) microfilaments D) lysosomes E) nucleoli

A

Cyanide binds with at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide would be found within the A) mitochondria. B) ribosomes. C) peroxisomes. D) lysosomes. E) endoplasmic reticulum.

A

The fact that the outer membrane of the nuclear envelope has bound ribosomes allows one to most reliably conclude that A) at least some of the proteins that function in the nuclear envelope are made by the ribosomes on the nuclear envelope. B) the nuclear envelope is not part of the endomembrane system. C) the nuclear envelope is physically continuous with the endoplasmic reticulum. D) small vesicles from the Golgi fuse with the nuclear envelope. E) nuclear pore complexes contain proteins.

A

Which component is a protein fiber of the extracellular matrix?

A

Which line in the graph represents the bag with the highest initial concentration of sucrose?

A

Which of the following are capable of converting light energy to chemical energy? A) chloroplasts B) mitochondria C) leucoplasts D) peroxisomes E) Golgi bodies

A

Which of the following contains hydrolytic enzymes? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

A

Which of the following possesses a microtubular structure similar to a basal body? A) centriole B) lysosome C) nucleolus D) peroxisome E) ribosome

A

Which structure is the site of the synthesis of proteins that may be exported from the cell? A) rough ER B) lysosomes C) plasmodesmata D) Golgi vesicles E) tight junctions

A

Green olives may be preserved in brine, which is a 30% salt solution. How does this method of preservation prevent microorganisms from growing in the olives?

A 30% salt solution is hypertonic to the bacteria, so they lose too much water and undergo plasmolysis.

Why does a hormone only act on specific cell types in an organism and not others?

A cell must have the appropriate receptor before it can bind to the hormone.

Detergent

A small amphipathic molecule. When these are added to the solution around a lipid bilayer, the hydrophobic tails of this molecule interact with the hydrophobic tails of the lipids and hydrophobic portions of transmembrane proteins; which displace the membrane phospholipids

Which of the following is most likely true of a protein that cotransports glucose and sodium ions into the intestinal cells of an animal?

A substance that blocks sodium ions from binding to the cotransport protein will also block the transport of glucose.

50) 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? A) Cilia and flagella arise from centrioles. B) Loss of basal bodies should prevent cells from dividing in two. C) Motor proteins such as dynein must have evolved before any of these four kinds of structure. D) Cilia and flagella evolved separately in the same ancestral eukaryotic organism. E) Natural selection for cell motility repeatedly selected for microtubular arrays in circular patterns in the evolution of each of these structures.

A) Cilia and flagella arise from centrioles.

38) What is the function of the nuclear pore complex found in eukaryotes? A) It regulates the movement of proteins and RNAs into and out of the nucleus. B) It synthesizes the proteins required to copy DNA and make mRNA. C) It selectively transports molecules out of the nucleus but prevents all inbound molecules from entering the nucleus. D) It assembles ribosomes from raw materials that are synthesized in the nucleus.

A) It regulates the movement of proteins and RNAs into and out of the nucleus.

29) Why is the smooth endoplasmic reticulum unable to synthesize proteins? A) No ribosomes are attached to its surface. B) There is no supply of free amino acids that it can easily access. C) It stores calcium, which is a known inhibitor of protein synthesis. D) It has no DNA to direct synthesis of proteins.

A) No ribosomes are attached to its surface.

60) Spherocytosis is a human blood disorder associated with a defective cytoskeletal protein in the red blood cells (RBCs). What do you suspect is the consequence of such a defect? A) abnormally shaped RBCs B) an insufficient supply of ATP in the RBCs C) an insufficient supply of oxygen-transporting proteins in the RBCs D) adherence of RBCs to blood vessel walls, causing plaque formation

A) abnormally shaped RBCs

53) Actin filaments have polarity. This means that the two ends can be identified due to structural differences. The plus end is the end to which subunits are added more rapidly, or the end of polymerization. Which of the following would enable you to identify the plus end of actin filaments? A) adding radiolabeled actin subunits to a mixture of actin filaments in which conditions are favorable for polymerization B) adding radiolabeled actin subunits to a mixture of actin filaments in which conditions favor depolymerization C) determining the ionic charge of the ends of the actin filaments

A) adding radiolabeled actin subunits to a mixture of actin filaments in which conditions are favorable for polymerization

The fact that the outer membrane of the nuclear envelope has bound ribosomes allows one to most reliably conclude thatA) at least some of the proteins that function in the nuclear envelope are made by the ribosomes on the nuclear envelope.B) the nuclear envelope is not part of the endomembrane system.C) the nuclear envelope is physically continuous with the endoplasmic reticulum.D) small vesicles from the Golgi fuse with the nuclear envelope.E) nuclear pore complexes contain proteins. A

A) at least some of the proteins that function in the nuclear envelope are made by the ribosomes on the nuclear envelope

6) The evolution of eukaryotic cells most likely involved ________. A) endosymbiosis of an aerobic bacterium in a larger host cell-the endosymbiont evolved into mitochondria B) anaerobic archaea taking up residence inside a larger bacterial host cell to escape toxic oxygen-the anaerobic bacterium evolved into chloroplasts C) an endosymbiotic fungal cell evolving into the nucleus D) acquisition of an endomembrane system and subsequent evolution of mitochondria from a portion of the Golgi apparatus

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

54) Amoebae move by crawling over a surface (cell crawling), which involves ________. A) growth of actin filaments to form bulges in the plasma membrane B) setting up microtubule extensions that vesicles can follow in the movement of cytoplasm C) reinforcing the pseudopod with intermediate filaments D) cytoplasmic streaming

A) growth of actin filaments to form bulges in the plasma membrane

15) Which of the following contains hydrolytic enzymes? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

A) lysosome

48) Movement of vesicles within the cell depends on what cellular structures? A) microtubules and motor proteins B) actin filaments and microtubules C) actin filaments and ribosomes D) centrioles and motor proteins E) actin filaments and motor proteins

A) microtubules and motor proteins

27) Cyanide binds with at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the ________. A) mitochondria B) ribosomes C) peroxisomes D) lysosomes E) endoplasmic reticulum

A) mitochondria

Which is one of the main energy transformers of cells? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

C

Integral membrane proteins

Also called transmembrane proteins. These are proteins that span the entire membrane and have segments facing the interior and exterior surfaces

What property of dishwashing liquid (detergent) makes it useful to wash grease from pans?

Amphipathic nature

Hydrophilic

Aquaporins' pores are relatively ______. (hydrophobic/hydrophilic)

Grana, thylakoids, and stroma are all components found in A) vacuoles. B) chloroplasts. C) mitochondria. D) lysosomes. E) nuclei.

B

In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization? A) chloroplast B) lysosome C) central vacuole D) peroxisome E) glyoxysome

B

The 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? A) rough ER B) smooth ER C) Golgi apparatus D) Nuclear envelope E) Transport vesicles

B

The 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?A) rough ERB) smooth ERC) Golgi apparatusD) Nuclear envelopeE) Transport vesicles

B

Under which of the following conditions would you expect to find a cell with a predominance of free ribosomes? A) a cell that is secreting proteins B) a cell that is producing cytoplasmic enzymes C) a cell that is constructing its cell wall or extracellular matrix D) a cell that is digesting food particles E) a cell that is enlarging its vacuole

B

Which component is a glycolipid?

B

Which line or lines in the graph represent(s) bags that contain a solution that is hypertonic at 50 minutes?

B

Which of the following is a compartment that often takes up much of the volume of a plant cell? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

B

Which of the following is a compartment that often takes up much of the volume of a plant cell?A) lysosomeB) vacuoleC) mitochondrionD) Golgi apparatusE) peroxisome B

B

Which of the following is present in a prokaryotic cell? A) mitochondrion B) ribosome C) nuclear envelope D) chloroplast E) ER

B

Which is one of the main energy transformers of cells?A) lysosomeB) vacuoleC) mitochondrionD) Golgi apparatusE) peroxisome

C

Which of the following makes it necessary for animal cells, although they have no cell walls, to have intercellular junctions? A) Cell membranes do not distinguish the types of ions and molecules passing through them. B) Large molecules, especially proteins, do not readily get through one, much less two adjacent cell membranes. C) Cell-to-cell communication requires physical attachment of one cell to another. D) Maintenance of connective tissue shape requires cells to adhere to one another. E) The relative shapelessness of animal cells requires a mechanism for keeping the cells aligned.

B

Which of the following relationships between cell structures and their respective functions is correct? A) cell wall: support, protection B) chloroplasts: chief sites of cellular respiration C) chromosomes: cytoskeleton of the nucleus D) ribosomes: secretion E) lysosomes: formation of ATP

B

Which structure is not part of the endomembrane system? A) nuclear envelope B) chloroplast C) Golgi apparatus D) plasma membrane E) ER

B

Why isnʹt the mitochondrion classified as part of the endomembrane system? A) It only has two membrane layers. B) Its structure is not derived from the ER. C) It has too many vesicles. D) It is not involved in protein synthesis. E) It is not attached to the outer nuclear envelope.

B

Cells A and B are the same size, shape, and temperature, but cell A is metabolically less active than cell B. and cell B is actively converting oxygen to water in cellular respiration. Oxygen will diffuse more rapidly into cell __________ because __________.

B ... the diffusion gradient in cell B is steeper

31) Which of the following is a major difference between prokaryotic cells and eukaryotic cells? A) Prokaryotes have cells but eukaryotes do not. B) Eukaryotic cells have more intracellular organelles than prokaryotes. C) Prokaryotes are not able to carry out aerobic respiration, relying instead on anaerobic metabolism. D) Prokaryotes are generally larger than eukaryotes.

B) Eukaryotic cells have more intracellular organelles than prokaryotes.

37) What can you infer about a high-molecular-weight protein that cannot be transported into the nucleus? A) It is too large. B) It lacks a nuclear localization signal (NLS). C) It contains errors in its amino acid sequence. D) It lacks a signal sequence.

B) It lacks a nuclear localization signal (NLS).

56) How is the structure of kinesin related to its function? A) Kinesin has two intertwined polypeptides that make up the stalk and enable it to contract and shorten. B) Kinesin has a tail region that binds to vesicles and two heads that can attach to microtubules. C) The kinesin tail has an ATP binding site to fuel its activities. D) Kinesin has two heads to attach to the vesicle being moved and a tail region that attaches to microtubules.

B) Kinesin has a tail region that binds to vesicles and two heads that can attach to microtubules.

42) Scientists have found that polypeptides which are normally synthesized in the endoplasmic reticulum are about 20 amino acids longer when they are synthesized by ribosomes not attached to the endoplasmic reticulum. What is a possible explanation for the greater length of these polypeptides? A) Ribosomes attached to the endoplasmic reticulum require fewer amino acids to function. B) The 20 amino acids serve as a signal (peptide) sequence that directs the forming polypeptides to the endoplasmic reticulum, where they are cleaved off during processing. C) The 20-amino-acid sequence helps the endoplasmic reticulum package these proteins for shipping to the Golgi. D) The protein has a different function in the cytosol than in the endoplasmic reticulum.

B) The 20 amino acids serve as a signal (peptide) sequence that directs the forming polypeptides to the endoplasmic reticulum, where they are cleaved off during processing.

46) Eukaryotic cells manufacture cytoskeletal proteins, which help to maintain cell shapes and functions. What would you predict about these proteins? A) They initially contain signal sequences that allow their entrance into the endoplasmic reticulum. B) They are manufactured on free ribosomes in the cytoplasm. C) They are glycosylated in the Golgi apparatus. D) They travel to the nucleus in a transport vesicle with a specific signal.

B) They are manufactured on free ribosomes in the cytoplasm.

20) Thylakoids, DNA, and ribosomes are all components found in ________. A) vacuoles B) chloroplasts C) mitochondria D) lysosomes E) nuclei

B) chloroplasts

43) Lysosomes that lack mannose-6-phosphate receptors ________. A) receive "modified" enzymes and are thus unable to break down carbohydrates B) do not receive enzyme shipments from the Golgi apparatus C) have unstable membranes D) stick to transport vesicles and impede the transfer of enzymes

B) do not receive enzyme shipments from the Golgi apparatus

8) A cell with a predominance of free ribosomes is most likely ________. A) primarily producing proteins for secretion B) primarily producing proteins in the cytosol C) constructing an extensive cell wall or extracellular matrix D) digesting large food particles E) enlarging its vacuole

B) primarily producing proteins in the cytosol

4) Which of the following is present in a prokaryotic cell? A) mitochondrion B) ribosome C) nuclear envelope D) chloroplast E) ER

B) ribosome

13) The 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? A) rough ER B) smooth ER C) Golgi apparatus D) nuclear envelope E) transport vesicles

B) smooth ER

28) A cell with an extensive area of smooth endoplasmic reticulum is specialized to ________. A) play a role in storage B) synthesize large quantities of lipids C) actively export protein molecules D) import and export protein molecules

B) synthesize large quantities of lipids

16) Which organelle often takes up much of the volume of a plant cell? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

B) vacuole

Which of these cannot rapidly pass directly through the phospholipids of the plasma membrane?

B, C, and D

Seawater is hypertonic to cytoplasm in vertebrate cells and in plant cells. If a red blood cell and a plant cell were placed in seawater, what would happen to the two types of cells?

Both cells would lose water; the red blood cell would shrivel, and the plant plasma membrane would pull away from the cell wall.

Identify the trend common to both the 15-day-old and 1-month-old guinea pigs' red blood cells.

Both experienced the most rapid uptake of glucose at the beginning of the experiment.

Which of the following statements is TRUE with regard to this animation?

Both sodium and potassium ions are transported against their concentration gradients.

Which of the following correctly compares the extracellular matrix (ECM) of animal cells to cell walls of plant cells?

Both the ECM and the plant cell wall are composed of varying mixtures of proteins and carbohydrates.

Adrenalin is a hormone that binds to a receptor in the plasma membrane. Which statement best explains why adrenalin can stimulate cells in both the heart and liver, yet trigger different responses (increasing heart rate versus releasing glucose)? -Both tissues have adrenalin receptors but signal transduction activates different target proteins in heart versus liver. -Different molecular forms of adrenalin affect heart versus liver. -Both tissues have adrenalin receptors but the receptors directly activate different target proteins in heart versus liver. -The hormone signal is amplified in one tissue but not the other.

Both tissues have adrenalin receptors but signal transduction activates different target proteins in heart versus liver.

What role does a transcription factor play in a signal transduction pathway?

By binding to DNA it triggers the transcription of a specific gene.

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? A) microtubules B) microfilaments C) plant cell walls D) intermediate filaments E) nuclear lamina

C

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? A) lipids B) starches C) proteins D) steroids E) glucose

C

Plasmodesmata in plant cells are most similar in function to which of the following structures in animal cells? A) peroxisomes B) desmosomes C) gap junctions D) extracellular matrix E) tight junctions

C

Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large and complex lipids. Which cellular organelle must be involved in this condition? A) the endoplasmic reticulum B) the Golgi apparatus C) the lysosome D) mitochondria E) membrane-bound ribosomes

C

The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by A) the physical separation of most membranes from each other. B) the transportation of membrane among the endomembrane system by small membrane vesicles. C) the function of the Golgi apparatus in sorting membrane components. D) the modification of the membrane components once they reach their final destination. E) the synthesis of lipids and proteins in each of the organelles of the endomembrane system.

C

The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined byA) the physical separation of most membranes from each other.B) the transportation of membrane among the endomembrane system by smallmembrane vesicles.C) the function of the Golgi apparatus in sorting membrane components.D) the modification of the membrane components once they reach their final destination.E) the synthesis of lipids and proteins in each of the organelles of the endomembrane system.

C

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 A) plant cells are capable of having a much higher surface-to-volume ratio than animal cells.B) plant cells have a much more highly convoluted (folded) plasma membrane than animal cells.C) plant cells contain a large vacuole that reduces the volume of the cytoplasm.D) animal cells are more spherical, while plant cells are elongated.E) the basic functions of plant cells are very different from those of animal cells.

C

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 A) plant cells are capable of having a much higher surface-to-volume ratio than animal cells. B) plant cells have a much more highly convoluted (folded) plasma membrane than animal cells. C) plant cells contain a large vacuole that reduces the volume of the cytoplasm. D) animal cells are more spherical, while plant cells are elongated. E) the basic functions of plant cells are very different from those of animal cells.

C

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? A) plasma membrane → primary cell wall → cytoplasm → tonoplast B) secondary cell wall → plasma membrane → primary cell wall → cytoplasm → tonoplast C) primary cell wall → plasma membrane → cytoplasm → tonoplast D) primary cell wall → plasma membrane → tonoplast → cytoplasm → vacuole E) tonoplast → primary cell wall → plasma membrane → cytoplasm

C

Which cell would be best for studying lysosomes? A) muscle cell B) nerve cell C) phagocytic white blood cell D) leaf cell of a plant E) bacterial cell

C

Which of the following statements correctly describes some aspect of protein disposal from prokaryotic cells? A) Prokaryotes are unlikely to be able to excrete proteins because they lack an endomembrane system. B) The mechanism of protein excretion in prokaryotes is probably the same as that in eukaryotes. C) Proteins that are excreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane. D) In prokaryotes, the ribosomes that are used for the synthesis of secreted proteins are located outside of the cell. E) Prokaryotes contain large pores in their plasma membrane that permit the movement of proteins out of the cell.

C

Which statement correctly characterizes bound ribosomes? A) Bound ribosomes are enclosed in their own membrane. B) Bound and free ribosomes are structurally different. C) Bound ribosomes generally synthesize membrane proteins and secretory proteins. D) The most common location for bound ribosomes is the cytoplasmic surface of the plasma membrane. E) All of the above.

C

Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids? A) ribosome B) lysosome C) smooth endoplasmic reticulum D) mitochondrion E) contractile vacuole

C

Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?A) ribosomeB) lysosomeC) smooth endoplasmic reticulumD) mitochondrionE) contractile vacuole

C

51) Which of the following statements about the cytoskeleton is TRUE? A) The cytoskeleton of eukaryotes is a static structure most resembling scaffolding used at construction sites. B) Although microtubules are common within a cell, actin filaments are rarely found outside of the nucleus. C) Movement of cilia and flagella is the result of motor proteins causing microtubules to move relative to each other. D) Chemicals that block the assembly of the cytoskeleton would have little effect on a cell's response to external stimuli. E) The cytoskeleton is produced by transport vesicles of the endomembrane system.

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

7) 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 most likely expect to be the immediate consequence? A) the loss of all nuclear function B) the inability of the nucleus to divide during cell division C) a change in the shape of the nucleus D) failure of chromosomes to carry genetic information E) inability of the ribosomes to produce proteins

C) a change in the shape of the nucleus

5) Which of the following is NOT found in a prokaryote? A) DNA B) a cell wall C) a mitochondrion D) a plasma membrane

C) a mitochondrion

30) Lysosomes are considered to be part of the endomembrane system because they ________. A) deposit end-products of digestion in the endoplasmic reticulum B) facilitate movement between stacks of the Golgi C) are formed from products synthesized by the endoplasmic reticulum and processed by the Golgi D) are composed largely of phospholipids

C) are formed from products synthesized by the endoplasmic reticulum and processed by the Golgi

39) The difference in lipid and protein composition between the membranes of the endomembrane system is largely determined by the ________. A) interconnection of most intracellular membranes to the nuclear envelope B) transportation of membrane lipids among the membranes of the endomembrane system by small membrane vesicles C) function of the Golgi apparatus in sorting and directing membrane components D) modification of the membrane components once they reach their final destination E) synthesis of different lipids and proteins in each of the organelles of the endomembrane system

C) function of the Golgi apparatus in sorting and directing membrane components

36) Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane? A) DNA B) amino acids C) mRNA D) phospholipids

C) mRNA

17) Which organelle is the primary site of ATP synthesis in eukaryotic cells? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

C) mitochondrion

18) Which plant cell organelle contains its own DNA and ribosomes? A) glyoxysome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

C) mitochondrion

22) Suppose a cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from ________. A) a bacterium B) an animal but not a plant C) nearly any eukaryotic organism D) a plant but not an animal E) any kind of prokaryotic organism

C) nearly any eukaryotic organism

45) In receptor-mediated endocytosis, receptor molecules initially project to the outside of the cell. Where do they end up after endocytosis? A) on the outside of vesicles B) on the inside surface of the cell membrane C) on the inside surface of the vesicle D) on the outer surface of the nucleus E) on the ER

C) on the inside surface of the vesicle

23) 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? A) plasma membrane → primary cell wall → cytoplasm → vacuole B) secondary cell wall → plasma membrane → primary cell wall → cytoplasm → vacuole C) primary cell wall → plasma membrane → cytoplasm → vacuole D) primary cell wall → plasma membrane → lysosome → cytoplasm → vacuole E) primary cell wall → plasma membrane → cytoplasm → secondary cell wall → vacuole

C) primary cell wall → plasma membrane → cytoplasm → vacuole

3) Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? A) lipids B) glycogen C) proteins D) cellulose E) nucleic acids

C) proteins

9) Which type of organelle or structure is primarily involved in the synthesis of oils, phospholipids, and steroids? A) ribosome B) lysosome C) smooth endoplasmic reticulum D) mitochondrion E) contractile vacuole

C) smooth endoplasmic reticulum

12) 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? A) the endoplasmic reticulum B) the Golgi apparatus C) the lysosome D) mitochondrion E) membrane-bound ribosomes

C) the lysosome

57) Motor proteins require energy in the form of ATP. ATP hydrolysis results in a conformational change that allows the protein to move along microtubular tracks (pathways). What structural component of the motor protein contains the ATP binding site and, therefore, changes shape to enable movement? A) the portion of the molecule that binds to the vesicle being transported B) the stalk C) the portion of the molecule that binds to the microtubular track along which the vesicle is being transported D) a location midway between the vesicle binding site and the portion of the molecule that binds to microtubular tracks

C) the portion of the molecule that binds to the microtubular track along which the vesicle is being transported

Which of the following would likely move through the lipid bilayer of a plasma membrane most rapidly?

CO2

against

Cells can move molecules in a directed manner, often ____ their electrochemical gradient. This requires energy input, because the cell must counteract the decrease in entropy that occurs when molecules are concentrated

In what way do the membranes of a eukaryotic cell vary?

Certain proteins are unique to each membrane.

What contains green pigment chlorophyll as well as enzymes and other molecules that function in photosynthesis?

Chloroplast

What can be found in only plants and algae and are the sites of photosynthesis?

Chloroplasts

Which of the following statements about chloroplasts and mitochondria is true?

Chloroplasts and mitochondria synthesize some of their own proteins.

Cells require which of the following to form cilia or flagella? A) centrosomes B) ribosomes C) actin D) A and B only E) A, B, and C

D

Which statement about the cytoskeleton is true?

Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm.

Which of the following statements about cotransport of solutes across a membrane is correct?

Cotransport proteins allow a single ATP-powered pump to drive the active transport of many different solutes.

Which of these is NOT correct? -Cyclic AMP binds to calmodulin. -Phospholipase C catalyzes the formation of IP3. -Tyrosine-kinase receptors consist of two polypeptides that join when activated by a signal molecule. -Ion channels are found on both the plasma membrane and the endoplasmic reticulum. -Kinases are enzymes that phosphorylate other molecules.

Cyclic AMP binds to calmodulin.

A cell has the following molecules and structures: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be a cell from A) a bacterium. B) an animal, but not a plant. C) a plant, but not an animal. D) a plant or an animal. E) any kind of organism.

D

A cell lacking the ability to make and secrete glycoproteins would most likely be deficient in its A) nuclear DNA. B) extracellular matrix. C) Golgi apparatus. D) B and C only E) A, B, and C

D

Cells of the pancreas will incorporate radioactively labeled amino acids into proteins. This ʺtaggingʺ 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 → Golgi → nucleus B) Golgi → ER → lysosome C) nucleus → ER → Golgi D) ER → Golgi → vesicles that fuse with plasma membrane E) ER → lysosomes → vesicles that fuse with plasma membrane

D

How does the cell multiply its peroxisomes? A) They bud off from the ER. B) They are brought into the cell from the environment. C) They are built de novo from cytosol materials. D) They split in two after they are too large. E) The cell synthesizes hydrogen peroxide and encloses it in a membrane.

D

If an individual has abnormal microtubules, due to a hereditary condition, in which organs or tissues would you expect dysfunction? A) limbs, hearts, areas with a good deal of contraction B) microvilli, alveoli, and glomeruli C) all ducts, such as those from salivary or sebaceous glands D) sperm, larynx, and trachea E) egg cells (ova), uterus, and kidneys

D

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures? A) sites of energy production in cellular respiration B) membrane proteins C) ribosomes D) cytoskeletons E) cellulose fibers in the cell wall

D

Organelles other than the nucleus that contain DNA include A) ribosomes. B) mitochondria. C) chloroplasts. D) B and C only E) A, B, and C

D

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 of all of these extracellular structures? A) They must block water and small molecules in order to regulate the exchange of matter and energy with their environment. B) They must permit information transfer between the cellʹs cytoplasm and the nucleus. C) They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume. D) They are constructed of materials that are largely synthesized in the cytoplasm and then transported out of the cell. E) They are composed of a mixture of lipids and carbohydrates.

D

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. Where are the corresponding reactions likely to occur in prokaryotic respiration? A) in the cytoplasm B) on the inner mitochondrial membrane C) on the endoplasmic reticulum D) on the inner plasma membrane E) on the inner nuclear envelope

D

The peroxisome gets its name from its interaction with hydrogen peroxide. If a liver cell is detoxifying alcohol and some other poisons, it does so by removal of hydrogen from the molecules. What, then, do the enzymes of the peroxisome do? A) combine the hydrogen with ATP B) use the hydrogen to break down hydrogen peroxide C) transfer the harmful substances to the mitochondria D) transfer the hydrogens to oxygen molecules

D

Which component is a peripheral protein?

D

Which of the following is a major cause of the size limits for certain types of cells? A) the evolution of larger cells after the evolution of smaller cells B) the difference in plasma membranes between prokaryotes and eukaryotes C) the evolution of eukaryotes after the evolution of prokaryotes D) the need for a surface area of sufficient area to allow the cellʹs function E) the observation that longer cells usually have greater cell volume

D

Which of the following is a major cause of the size limits for certain types of cells? A) the evolution of larger cells after the evolution of smaller cellsB) the difference in plasma membranes between prokaryotes and eukaryotes C) the evolution of eukaryotes after the evolution of prokaryotesD) the need for a surface area of sufficient area to allow the cellʹs functionE) the observation that longer cells usually have greater cell volume

D

Which of the following produces and modifies polysaccharides that will be secreted? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

D

Which structure is common to plant and animal cells? A) chloroplast B) wall made of cellulose C) central vacuole D) mitochondrion E) centriole

D

Which of the following produces and modifies polysaccharides that will be secreted?A) lysosomeB) vacuoleC) mitochondrionD) Golgi apparatusE) peroxisome

D golgi

40) What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell? A) ER → Golgi → nucleus B) Golgi → ER → lysosome C) nucleus → ER → Golgi D) ER → Golgi → vesicles that fuse with plasma membrane E) ER → lysosomes → vesicles that fuse with plasma membrane

D) ER → Golgi → vesicles that fuse with plasma membrane

14) Which of the following produces and modifies polysaccharides that will be secreted? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

D) Golgi apparatus

58) Cilia and flagella bend because of ________. A) conformational changes in ATP that thrust microtubules laterally B) a motor protein called radial spokes C) the quick inward movements of water by osmosis D) a motor protein called dynein

D) a motor protein called dynein

25) 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, ________. A) mitochondria and chloroplasts B) chloroplasts and peroxisomes C) peroxisomes and chloroplasts D) chloroplasts and mitochondria E) mitochondria and peroxisomes

D) chloroplasts and mitochondria

47) Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures? A) mitochondria and chloroplasts B) membrane proteins of the inner nuclear envelope C) free ribosomes and ribosomes attached to the ER D) components of the cytoskeleton E) cellulose fibers in the cell wall

D) components of the cytoskeleton

24) Where are proteins produced other than on ribosomes free in the cytosol or ribosomes attached to the ER? A) in the extracellular matrix B) in the Golgi apparatus C) in lysosomes D) in mitochondria E) in the nucleolus

D) in mitochondria

21) In a plant cell, DNA may be found ________. A) only in the nucleus B) only in the nucleus and mitochondria C) only in the nucleus and chloroplasts D) in the nucleus, mitochondria, and chloroplasts E) in the nucleus, mitochondria, chloroplasts, and peroxisomes

D) in the nucleus, mitochondria, and chloroplasts

44) Asbestos is a material that was once used extensively in construction. One risk from working in a building that contains asbestos is the development of asbestosis caused by the inhalation of asbestos fibers. Cells will phagocytize asbestos but are not able to degrade it. As a result, asbestos fibers accumulate in ________. A) mitochondria B) ribosomes C) peroxisomes D) lysosomes

D) lysosomes

32) Suppose a young boy is always tired and fatigued, suffering from a metabolic disease. Which of the following organelles is most likely involved in this disease? A) lysosomes B) Golgi apparatus C) ribosomes D) mitochondria

D) mitochondria

33) When yeast cells are transferred from anaerobic to aerobic growth conditions, which of these organelles become much more numerous? A) lysosomes B) Golgi apparatus C) ribosomes D) mitochondria

D) mitochondria

26) Which structure is common to plant and animal cells? A) chloroplast B) wall made of cellulose C) central vacuole D) mitochondrion E) centriole

D) mitochondrion

55) Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP (because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing? A) an axon B) contractile microfilaments C) endoplasmic reticulum D) motor proteins

D) motor proteins

34) An organism with a cell wall would most likely be unable to take in materials through ________. A) diffusion B) osmosis C) active transport D) phagocytosis E) facilitated diffusion

D) phagocytosis

35) A primary objective of cell fractionation (including differential centrifugation) is to ________. A) view the structure of cell membranes B) sort cells based on their size and weight C) determine the size of various organelles D) separate the major organelles E) separate lipid-soluble from water-soluble molecules

D) separate the major organelles

2) In a bacterium, we will find DNA in ________. A) a membrane-enclosed nucleus B) mitochondria C) the endoplasmic reticulum D) the nucleoid E) ribosomes

D) the nucleoid

A mycoplasma is an organism with a diameter between 0.1 and 1.0 μm. What does its size tell you about how it might be classified? A) It must be a single celled protist. B) It must be a single celled fungus. C) It could be almost any typical bacterium. D) It could be a typical virus. E) It could be a very small bacterium.

E

A mycoplasma is an organism with a diameter between 0.1 and 1.0 μm. What does its size tell you about how it might be classified?A) It must be a single celled protist.B) It must be a single celled fungus.C) It could be almost any typical bacterium.D) It could be a typical virus.E) It could be a very small bacterium

E

All of the following are part of a prokaryotic cell except A) DNA. B) a cell wall. C) a plasma membrane. D) ribosomes. E) an endoplasmic reticulum.

E

Centrioles, cilia, flagella, and basal bodies have remarkably similar structural elements and arrangements. This leads us to which of the following as a probable hypothesis? A) Disruption of one of these types of structure should necessarily disrupt each of the others as well. B) Loss of basal bodies should lead to loss of all cilia, flagella, and centrioles. C) Motor proteins such as dynein must have evolved before any of these four kinds of structure. D) Evolution of motility, of cells or of parts of cells, must have occurred only once. E) Natural selection for motility must select for microtubular arrays in circular patterns.

E

Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through A) plasmodesmata. B) intermediate filaments. C) tight junctions. D) desmosomes. E) gap junctions.

E

Microfilaments are well known for their role in which of the following? A) ameboid movement B) formation of cleavage furrows C) contracting of muscle cells D) A and B only E) A, B, and C

E

The Golgi apparatus has a polarity or sidedness to its structure and function. Which of the following statements correctly describes this polarity? A) Transport vesicles fuse with one side of the Golgi and leave from the opposite side. B) Proteins in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. C) Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. D) Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. E) All of the above correctly describe polar characteristics of the Golgi function.

E

Which component is cholesterol?

E

Which of the following contains enzymes that transfer hydrogen from various substrates to oxygen? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

E

Which structure-function pair is mismatched? A) nucleolus; production of ribosomal subunits B) lysosome; intracellular digestion C) ribosome; protein synthesis D) Golgi; protein trafficking E) microtubule; muscle contraction

E

11) The Golgi apparatus has a polarity, or sidedness, to its structure and function. Which of the following statements correctly describes this polarity? A) Transport vesicles fuse with one side of the Golgi and leave from the opposite side. B) Proteins in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. C) Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. D) Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. E) All of the listed responses correctly describe polarity characteristics of the Golgi function.

E) All of the listed responses correctly describe polarity characteristics of the Golgi function.

49) Which of the following correctly matches a component of the cytoskeleton to one of its functions? A) Microfilaments form the nuclear lamina. B) Microtubules help animal cells divide in two. C) Microfilaments cause ciliary bending. D) Intermediate filaments contribute to cytoplasmic streaming. E) Microtubules move chromosomes.

E) Microtubules move chromosomes.

1) All of the following are part of a prokaryotic cell EXCEPT ________. A) DNA B) a cell wall C) a plasma membrane D) ribosomes E) an endoplasmic reticulum

E) an endoplasmic reticulum

59) Which structure—function pair is mismatched? A) nucleolus—production of ribosomal subunits B) lysosome—intracellular digestion C) ribosome—protein synthesis D) Golgi—protein trafficking E) microtubule—muscle contraction

E) microtubule—muscle contraction

19) Which animal cell organelle contains enzymes that transfer hydrogen from various substrates to oxygen? A) lysosome B) vacuole C) mitochondrion D) Golgi apparatus E) peroxisome

E) peroxisome

What is the most likely pathway taken by a newly synthesized protein that will be secreted by a cell?

ER → Golgi → vesicles that fuse with plasma membrane

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells?

Eukaryotic cells are compartmentalized, which allows for specialization

Which of the following correctly describes some aspect of exocytosis or endocytosis?

Exocytosis and endocytosis change the surface area of the plasma membrane.

Carrier proteins

Facilitated diffusion can occur through these, which are special membrane proteins that change shape during transport

True or false? Active transport differs from passive transport in that active transport does not require an input of energy.

False

True or false? During active transport through the sodium-potassium pump, ATP hydrolysis provides the energy to pump three sodium ions into the cell for every two potassium ions pumped out of the cell.

False

Amoebae move by crawling over a surface (cell crawling), which involves what?

Growth of actin filaments to form bulges in the plasma membrane.

Label as either G protein-coupled receptors, receptor tyrosine kinases, both types of receptors, or neither receptor: -receptor is located in the plasma membrane -binding of the signaling molecule allows ions to flow through a channel in the receptor -catalyzes the transfer of a phosphate group to the receptor -binding site for signaling molecule is located on the extracellular side of the cell -interact directly with G proteins -binding of the signaling molecule forms a dimer

G protein-coupled receptors: interact directly with G proteins receptor tyrosine kinases: catalyzes the transfer of a phosphate group to the receptor, binding of the signaling molecule forms a dimer both types of receptors: binding site for signaling molecule is located on the extracellular side of the cell, receptor is located in the plasma membrane neither receptor: binding of the signaling molecule allows ions to flow through a channel in the receptor

A toxin that inhibits the production of GTP would interfere with the function of a signal transduction pathway that is initiated by the binding of a signal molecule to _____ receptors.

G-protein-linked

Epinephrine acts as a signal molecule that attaches to _____ proteins.

G-protein-linked receptor

The binding of the signal molecule to the receptor side on the outside of a G protein receptor, leads to the activation of the tethered G proteins on the inside of the membrane due the the replacement of __________ with _________.

GDP, GTP

_____ aid in the coordination of the activities of adjacent animal cells.

Gap (communicating) junctions

Complete the diagram below using the following steps. Drag the pink labels to the pink targets, indicating the relative concentration of glucose inside and outside the cell. Drag the correct white label to the white target, indicating the direction that Na+ ions and glucose move through the cotransporter. Drag the blue labels to complete the sentences on the right, indicating how Na+ ions and glucose move through the cotransporter relative to their electrochemical and concentration gradients.

In cotransport, the energy required to move one solute against its concentration or electrochemical gradient is provided by an ion moving into the cell down its electrochemical gradient. The ion that moves into the cell down its gradient is usually the same ion that is pumped out of the cell by an active transport pump: for example, Na+ in animal cells using the sodium-potassium pump, or H+ in plants and prokaryotes using the proton pump. In the case of the glucose-sodium cotransporter in animals, Na+ moves back into the cell down its electrochemical gradient, providing the energy for glucose to move into the cell against its concentration gradient. The energy for glucose transport into the cell is supplied indirectly by the sodium-potassium pump's hydrolysis of ATP, and directly by the Na+ electrochemical gradient created by the pump.

Which of the following is true of osmosis?

In osmosis, water moves across a membrane from areas of lower solute concentration to areas of higher solute concentration.

Scanning electron microscope

In the freeze-fracture electron microscopy (freeze and fracture the membrane), you use what? (SEM)

Of the three:microtubule, microfilament, and intermediate filament, which is the most permanent cytoskeleton fixture?

Intermediate filament

high to low and like to unlike

Ions always move through the channels from regions of ____ concentration to ____ concentration; from areas of ____ charge to areas of ____ charge

Which of the following is a characteristic feature of a carrier protein in a plasma membrane?

It exhibits a specificity for a particular type of molecule.

Which of the following statements about diffusion is true?

It is a passive process.

What is the function 0f the nuclear pore complex found in eukaryotes?

It regulates the movement of proteins and RNA's into and out of the nucleus.

Molecular filter

Key side chains in the pores act as a _____ ______. Because of the distance between them, only substances that can interact with all of the pores get through

How can a lipid be distinguished from a sugar?

Lipids are mostly nonpolar.

Gated channels

Many aquaporins and ion channels are this; they open or close in response to a signal (bonding of certain molecule or change in electrical voltage)

Which of the following statements concerning carbohydrates associated with the plasma membrane is correct?

Membrane carbohydrates function primarily in cell-cell recognition.

What distinguishes facilitated diffusion from simple diffusion?

Membrane proteins help move molecules across the membrane.

Which of the following functions of membrane proteins is important in tissue formation during embryonic development in animals?

Membrane proteins with short sugar chains form identification tags that are recognized by other cells.

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

Microtubules and motor proteins.

Cyanide binds to at least one molecule involved in producing ATP. If a cell is exposed to cyanide, most of the cyanide will be found within the

Mitochondria

What structure is common to plants and animals?

Mitochondrion

Passive transport

Movement of all substances across a membrane does not require energy, it is powered by diffusion along an electrochemical gradient

Sodium Potassium pump

Na+/K+-ATPase, Na+/K+ refers to the ions transported, ATP indicates that ATP is needed, -ase shows that it is an enzyme

Eukaryotic cells manufacture cytoskeletal proteins which help to maintain cell shape and functions. Where are they manufactured?

On the free ribosomes in the cytoplasm.

Which of the following most accurately describes selective permeability?

Only certain molecules can cross a cell membrane.

Select the correct statement about osmosis.

Osmosis is the diffusion of water molecules across a selectively permeable membrane.

Three lab groups carried out an experiment to identify the correct molarities for five solutions. Each unknown contained one of the following sucrose concentrations: 0.0 M, 0.2 M, 0.4 M, 0.6 M, 0.8 M, and 1.0 M. Each data entry represents the average of 3 sample replications of 1 cm3 sweet potato cubes expressed as percent change in mass after an overnight (24 hr) soak in the unknown solutions. From the data given, which statement most accurately describes what is occurring in response to a particular unknown solution.

Osmosis of water molecules from unknown solution A likely caused the increase in mass observed.

Which of the following particles could diffuse easily through a cell membrane?

Oxygen (O2)

Which of the following statements about passive transport is correct?

Passive transport permits the solute to move in either direction, but the net movement of solute molecules occurs down the concentration gradient of the molecule.

You have a planar bilayer with equal amounts of saturated and unsaturated phospholipids. After testing the permeability of this membrane to glucose, you increase the proportion of unsaturated phospholipids in the bilayer. What will happen to the membrane's permeability to glucose?

Permeability to glucose will increase.

_____ catalyzes the production of _____, which then opens an ion channel that releases _____ into the cell's cytoplasm.

Phospholipase C ... IP3 .... Ca2+

Which of the following statements about the role of phospholipids in the structure and function of biological membranes is correct?

Phospholipids form a selectively permeable structure.

How is phosphorylation important in a signal transduction cascade?

Phosphorylation will turn an inactive protein into an active one, which triggers another response in the cell.

Which statement is correct concerning how the molecular composition of a plant cell wall compares with the ECM of animal cells? -In the plant cell wall, the ground substance surrounding the fibers contains carbohydrates; in the ECM it does not. -The fibers in a plant cell wall are proteins; ECM fibers are dominated by carbohydrates. -Plant cell walls exhibit fundamentally different design principles than ECM. -Plant cell wall fibers consist of carbohydrates; ECM fibers are dominated by proteins.

Plant cell wall fibers consist of carbohydrates; ECM fibers are dominated by proteins.

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. In what order to those structures occur?

Primary cell wall > plasma membrane > cytoplasm > vacuole.

Amphipathic

Proteins that are _______ can be put in lipid bilayers

Peripheral membrane proteins

Proteins that bind to the membrane without binding to it

Large numbers of ribosomes are present in cells that specialize in producing which molecule?

Protiens.

Proton pumps are used in various ways by members of every domain of organisms: Bacteria, Archaea, and Eukarya. What does this most probably mean?

Proton gradients across a membrane were used by cells that were the common ancestor of all three domains of life.

A semipermeable membrane is placed between the following solutions. Which solution will decrease in volume?

Solution A: 1.4% (m/v) starch

Which solution will increase in volume?

Solution D: 12.4% (m/v) NaCl

If you mechanically shook a mixture of phospholipids and water, what would you expect to see when you observe the solution using an electron microscope?

Some lipids will have formed tiny vesicles filled with water.

What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane?

Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores.

Fluid mosaic model

Suggested by Singer and Nicolson, that membranes are mosaic of phospholipids and different types of proteins; a dynamic and fluid structure

Which statement most accurately predicts what would happen to animal cells if they are treated with an enzyme that cuts integrin molecules? -The ECM surrounding the cells would dissolve. -The cytoskeleton of the cells would fall apart. -The adhesion of the cells to adjacent cells would be weakened. -The cell wall surrounding the cells would dissolve.

The adhesion of the cells to adjacent cells would be weakened.

When a plant cell, such as one from a rose stem, is submerged in a very hypotonic solution, what is likely to occur?

The cell will become turgid.

What will happen to a red blood cell (RBC), which has an internal ion concentration of about 0.9 percent, if it is placed into a beaker of pure water?

The cell would swell because the water in the beaker is hypotonic relative to the cytoplasm of the RBC.

Which of the following statements is true about the net movement of an ion across a membrane by passive diffusion through a membrane channel?

The charge on the other side of the membrane is generally the opposite of the ion's charge.

Which statement is correct?

The contents of a red blood cell are hypertonic to distilled water.

Which of the following is a reasonable explanation for why unsaturated fatty acids help keep a membrane more fluid at lower temperatures?

The double bonds form kinks in the fatty acid tails, preventing adjacent lipids from packing tightly.

How does the function of an intracellular receptor differ from that of a membrane receptor?

The intracellular receptor binds DNA or binds a Transcription Factor protein that binds DNA

You have just discovered an organism that lives in You have just discovered an organism that lives in extremely cold environments. Which of the following would you predict to be true about the phospholipids in its membranes, compared to phospholipids in the membranes of organisms that live in warmer environments?

The membrane phospholipids of cold-adapted organisms will have more unsaturated hydrocarbon tails.

GLUT-1

The membrane protein responsible for transporting glucose across plasma membranes; to increase the membranes permeability to glucose - (usually not very permeable for glucose)

What causes cilia and flagella to bend?

The motor protein dynein.

Consider the transport of protons and sucrose into a plant cell by the sucrose-proton cotransport protein. Plant cells continuously produce a proton gradient by using the energy of ATP hydrolysis to pump protons out of the cell. Why, in the absence of sucrose, do protons not move back into the cell through the sucrose-proton cotransport protein?

The movement of protons through the cotransport protein cannot occur unless sucrose moves at the same time.

Interior

The nonpolar residues of amino acids would be stable in which part of the bilayer?

A patient was involved a serious accident and lost a large quantity of blood. In an attempt to replenish body fluids, distilled waterequal to the volume of blood lostis added to the blood directly via one of his veins. What will be the most probable result of this transfusion?

The patient's red blood cells will swell and possibly burst because the blood has become hypotonic compared to the cells.

Exterior

The polar residues of amino acids would be stable in which part of the bilayer?

Which of the following factors does not affect membrane permeability?

The polarity of membrane phospholipids

Which of the following statements about osmosis is correct?

The presence of aquaporins (proteins that form water channels in the membrane) should speed up the process of osmosis.

Which factors affect the rate of osmotic movement of water?

The rate of osmosis increases with increasing differences in solute concentrations between two solutions separated by a selectively permeable membrane.

Which of the following hypotheses is a reasonable explanation for the data represented in the graph?

The red blood cells of older guinea pigs have fewer glucose transporter proteins than the red blood cells of younger guinea pigs.

What would be observed by live-cell fluorescence microscopy immediately after HIV entry if HIV is endocytosed first, and then later fuses with the endocytotic vesicle membrane?

The red fluorescent dye-labeled lipids will appear in the infected cell's interior.

Active transport requires an input of energy and can also generate voltages across membranes. Based on this information, which of the following statements is true?

The sodium-potassium pump hydrolyzes ATP and results in a net positive change outside the cell membrane.

Which of the following statements about the sodium-potassium pump is correct?

The sodium-potassium pump moves Na+ and K+ in opposite directions, resulting in a net negative charge inside the cell.

Cell membranes are asymmetrical. Which of the following statements is the most likely explanation for the membrane's asymmetrical nature?

The two sides of a cell membrane face different environments and carry out different functions.

Which of the following statements about a typical plasma membrane is correct?

The two sides of the plasma membrane have different lipid and protein composition.

Refer to the figure. After the system reaches equilibrium, what changes are observed?

The water level is higher in side A than in side B.

What is the main difference between the trends for the 15-day-old and 1-month-old guinea pigs' red blood cells?

The younger guinea pig's cells took up more glucose than the older guinea pig's cells at all incubation times.

Why are lipids and proteins free to move laterally in membranes?

There are only weak hydrophobic interactions in the interior of the membrane.

When a cell is in equilibrium with its environment, which of the following occurs for substances that can diffuse through the cell?

There is random movement of substances into and out of the cell.

ATP

This provides the energy for active transport by transferring phosphate group (HPO4, 2-) to the pump

What happens when two solutions separated by a selectively permeable membrane reach osmotic equilibrium?

Water molecules move between the two solutions, but there is no net movement of water across the membrane.

Channel proteins

These are selective, cells have many different kinds in their membranes. Each has a structure that only lets a certain type of ion or molecule to pass through

Proteins

These can be amphipathic because their monomers, amino acids, have side chains that range from nonpolar to polar (charged)

Aquaporins

These channels allow water to cross the plasma membrane 10+ times faster than if this channel was missing. These only let water through but not small molecules/ions. Also known as water pores.

Aquaporins

These have a pore lined with polar functional groups (carbonyl)

Selective permeability of lipid bilayer, specificity of proteins involved in transport, and active transport

These three factors allow cells to to create an internal environment that is much different from the external one

Cystic fibrosis

This disease results from the mismanagement of osmosis. Chloride ions may not be able to leave the cell, causing the consistency to become to thick

Stored energy

This is formed by the electrochemical gradients established by the Na+/K+-ATPase

Facilitated diffusion

This is the passive transport of substances that otherwise wouldn't cross; like channel proteins allow ions or polar molecules to cross lipid bilayers

Glucose can be moved into cells via an active transport mechanism when the concentration of glucose inside the cell is higher than the concentration of glucose outside of the cell. This active transport mechanism moves glucose and sodium into the cell at the same time. The glucose moves up its gradient and the sodium moves down its gradient. Which of the following statements about this mechanism is accurate?

To pump glucose up its concentration gradient, sodium moves down its concentration gradient, and the distribution of sodium ions across the membrane forms an electrochemical gradient that drives this mechanism.

Active transport

Transport against an electrochemical gradient

In facilitated diffusion, what is the role of the transport protein?

Transport proteins provide a hydrophilic route for the solute to cross the membrane.

Which membrane protein would be used to move glucose across a membrane from a region of higher concentration to a region of lower concentration?

Transporter

True or false? Osmosis is a type of diffusion.

True

True or false? The water-soluble portion of a phospholipid is the polar head, which generally consists of a glycerol molecule linked to a phosphate group.

True

What organelle often takes up much of the volume of a plant cell?

Vacuole.

A single plant cell is placed in an isotonic solution. Salt is then added to the solution. Which of the following would occur as a result of the salt addition?

Water would leave the cell by osmosis, causing the volume of the cytoplasm to decrease.

Which of the following molecular movements is due to diffusion or osmosis?

When a plant cell is placed in concentrated salt water, water moves out of the cell.

glucose

When this binds to GLUT-1 it changes its shape in order to move the sugar through the hydrophobic region of the membrane and release it on the other side

granum

a "stack" of thylakoid within the chloroplast

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 consequence?

a change in the shape of the nucleus

Refer to the figure. If you examine side A after three days, you should find _____.

a decrease in the concentration of NaCl and a decrease in the water level

Which of the following factors would tend to increase membrane fluidity?

a greater proportion of unsaturated phospholipids

The concentration of solutes in a red blood cell is about 2%, but red blood cells contain almost no sucrose or urea. Sucrose cannot pass through the membrane, but water and urea can. Osmosis would cause red blood cells to shrink the most when immersed in which of the following solutions?

a hypertonic sucrose solution

Which of the following would be LEAST likely to diffuse through a plasma membrane without the help of a transport protein?

a large, polar molecule

The receptor type with the fastes response time, which often leads to a change in membrane voltage is _________________.

a ligand gated channel receptor

What is the definition of the cytoskeleton?

a network of fibers that organize structures and activities in the cell. It extends throughout the cytoplasm.

Phospholipids are composed of

a phosphate group, a glycerol, and fatty acids

In addition to the fundamental structures required to be defined as a cell, a particular cell also has a nucleus and chloroplasts. Based on this information, this cell could be _____.

a protistal cell and a plant cell

Which of the following would increase the electrochemical gradient across a membrane?

a proton pump

In this diagram of the plasma membranes of two adjoining cells, identify the protein indicated by the white arrow, including its function.

a receptor protein that binds with a signaling molecule and relays the message into the cell by activating other molecules inside the cell

In which of the following would there be the greatest need for osmoregulation?

a salmon moving from a river into an ocean

Can you label some components associated with the plasma membrane and identify the functions of membrane proteins?

a. phospholipid bilayer b. fibers of extracellular matrix (ECM) c. enzymatic activity d. microfilaments of cytoskeleton e. attachment to ECM and cytoskeleton f. signal transduction g. transport h. intercellular junctions i. cell-cell recognition

Certain molecules use diffusion to cross the plasma membrane.

a. side with higher concentration of molecules b. plasma membrane c. side with lower concentration of molecules d. diffusion causes a net movement of molecules down their concentration gradient

If the concentration of phosphate in the cytosol is 2.0 mM and the concentration of phosphate in the surrounding fluid is 0.1 mM, how could the cell increase the concentration of phosphate in the cytosol?

active transport

The sodium-potassium pump uses energy from ATP to move sodium ions out of the cell, and potassium ions into the cell. This is an example of

active transport.

transport proteins

allowing solute molecules to enter the cell

All molecules have energy that causes thermal motion. One result of thermal motion is diffusion: the tendency of substances to spread out evenly in the available space. Although the motion of each individual molecule is random, there can be directional motion of an entire population of molecules. Consider a chamber containing two different types of dye molecules, purple and orange. The chamber is divided into two compartments (A and B) by a membrane that is permeable to both types of dye. Initially (left image), the concentration of the orange dye is greater on side A, and the concentration of the purple dye is greater on side B. With time, the dye molecules diffuse to a final, equilibrium state (right image) where they are evenly distributed throughout the chamber. Two diagrams showing a chamber containing purple and orange balls--one before diffusion and one after diffusion. The chamber is divided into two compartments by a membrane that is permeable to both purple and orange balls. The diagram on the left shows the initial condition, with 9 orange balls on the left side of the membrane and 3 orange balls on the right. There are 2 purple balls on the left and 6 purple balls on the right. The diagram on the right shows the equilibrium state after diffusion has occurred. There are 6 orange balls on the left and 6 orange balls on the right. There are 4 purple balls on the left and 4 purple balls on the right. Drag the labels onto the table to indicate when each statement is true. Labels can be used once, more than once, or not at all.

always only before equilibrium is reached only before equilibrium is reached never only at equilibrium

For a protein to be an integral membrane protein, it would have to be _____.

amphipathic, with at least one hydrophobic region

A protein kinase activating many other protein kinases is an example of _____.

amplification

Which of the following statements correctly describes the normal tonicity conditions for typical plant and animal cells? The animal cell is in _____.

an isotonic solution, and the plant cell is in a hypotonic solution

Cholesterol is an important component of

animal cell membranes

Which of the following allows water to move much faster across cell membranes?

aquaporins

Lipids _____.

are insoluble in water

Some regions of the plasma membrane, called lipid rafts, have a higher concentration of cholesterol molecules. At higher temperatures, these regions _____.

are less fluid than the surrounding membrane

What is the definition of free ribosomes?

are present in the cytosol

What does cilia and flagella do?

are protrusions from some cells that aid in cellular locomotion. They are formed from specialized groupings of microtubules called basal bodies.

Under which of the following conditions would you expect to find a cell with a predominance of free ribosomes?A) a cell that is secreting proteinsB) a cell that is producing cytoplasmic enzymesC) a cell that is constructing its cell wall or extracellular matrixD) a cell that is digesting food particlesE) a cell that is enlarging its vacuole

b

In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization?A) chloroplastB) lysosomeC) central vacuoleD) peroxisomeE) glyoxysome

b, lysososme

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

b.rough ER

Consider two cells with the same volume but with very different surface areas due to differences in their shapes. The cell with the larger surface area is likely to _____.

be involved in the rapid uptake of compounds from the cell's environment

The receptors for steroid hormones are located inside the cell, instead of on the membrane surface like most other signal receptors. Why is this not a problem for steroids?

because steroid hormones are lipid soluble so can readily diffuse through the lipid bilayer of the cell membrane

In an HIV-infected cell producing HIV virus particles, the viral glycoprotein is expressed on the plasma membrane. How do the viral glycoproteins get to the plasma membrane? They are synthesized _____.

by ribosomes in the rough ER and arrive at the plasma membrane in the membrane of secretory vesicles

Tay-Sachs disease is a human genetic abnormality that results in cells accumulating and becoming clogged with very large and complex lipids. Which cellular organelle must be involved in this condition? A) the endoplasmic reticulumB) the Golgi apparatusC) the lysosomeD) mitochondriaE) membrane-bound ribosomes

c

Which of the following statements correctly describes some aspect of protein disposal from prokaryotic cells?A) Prokaryotes are unlikely to be able to excrete proteins because they lack an endomembrane system.B) The mechanism of protein excretion in prokaryotes is probably the same as that in eukaryotes.C) Proteins that are excreted by prokaryotes are synthesized on ribosomes that are bound to the cytoplasmic surface of the plasma membrane.D) In prokaryotes, the ribosomes that are used for the synthesis of secreted proteins are located outside of the cell.E) Prokaryotes contain large pores in their plasma membrane that permit the movement of proteins out of the cell.

c

Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?a.contractile vacuole b.ribosome c.Smooth ER d.lysosome e.mitochondrion

c.Smooth ER

The 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? a.nuclear envelope b.rough ER c.smooth ER d.golgi apparatus

c.smooth ER

The enzyme Adenylyl Cyclase is actived by the activated alpha unit of G protein. Once activated the adenylyl clyclase produces the second messenger molecule ____________, which transduces the response of the cell.

cAMP

The amplifier enayme Guanylyl Cyclase produces the second messenger ___________ and this enzyme is activated by a ____________ like tyrosine kinase.

cGMP.....receptor enzyme

Which of these is a receptor for calcium ions?

calmodulin

According to the fluid mosaic model of cell membranes, phospholipids _____.

can move laterally along the plane of the membrane

simplest collection of matter that can live

cell

An animal cell lacking oligosaccharides on the external surface of its plasma membrane would likely be impaired in which function?

cell-cell recognition

A polysaccharide that is used to synthesize cell walls and help maintain their shape. -Choose one: Cellulose, plasmodesmata, collagen, gap junctions, or tight junctions -Choose one: animal or plant

cellulose, plant

which of the following are found in animal cells but not plant cells?

centrioles

Which variable is the dependent variable--the variable that depended on the treatment and was measured by the researchers? Is the dependent variable on the x-axis or the y-axis?

concentration of radioactive glucose; on the y-axis

Singer and Nicolson's fluid mosaic model of the membrane proposed that membranes_____.

consist of protein molecules embedded in a fluid bilayer of phospholipids

The phosphate transport system in bacteria imports phosphate into the cell even when the concentration of phosphate outside the cell is much lower than the cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient across the membrane (more acidic outside the cell than inside the cell). Phosphate transport is an example of _____.

cotransport

The movement of glucose into a cell against a concentration gradient is most likely to be accomplished by which of the following?

cotransport of the glucose with a proton or sodium ion that was pumped across the membrane using the energy of ATP hydrolysis

In some cells, there are many ion electrochemical gradients across the plasma membrane even though there are usually only one or two proton pumps present in the membrane. The gradients of the other ions are most likely accounted for by _____.

cotransport proteins

Which of the following is least likely to be important in holding the components of a biological membrane together?

covalent interactions between the phospholipid and protein components of the membrane

A red blood cell is placed into each of the following solutions. Indicate whether crenation, hemolysis, or neither will occur. Solution A: 3.21% (m/v) NaCl Solution B: 1.65% (m/v) glucose Solution C: distilled H2O Solution D: 6.97% (m/v) glucose Solution E: 5.0% (m/v) glucose and 0.9%(m/v) NaCl Drag each solution to the appropriate bin.

crenation: a d e hemolysis: b c

Which of these acts as a second messenger?

cyclic AMP

Integrins are integral membrane proteins. They are often attached to _______.

cytoskeletal proteins and proteins in the extracellular matrix

Where would you expect to find proteins involved with movement of structures within a cell?

cytoskeleton

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules? a.steroids b.starches c.lipids d.proteins

d.proteins

A primary objective of cell fractionation is to what? a.determine the size of various organelles b.identify the enzymes outside the organelles c.view the structure of cell membranes d.separate major organelles so that their funtions can be determined

d.separate major organelles so that their functions can be determined

Based on Figure 7.18 in your textbook, which of these experimental treatments would increase the rate of sucrose transport into the cell?

decreasing extracellular pH

Familial hypercholesterolemia is characterized by _____.

defective LDL receptors on the cell membranes

Because cell walls consist of a cross-linked network of long filaments embedded in a stiff surrounding material, they can be called _______,

fiber composites

If they are longer and less numerous (usually only one or two) they are termed what?

flagella

Small channels that form across the plasma membranes of adjacent cells; especially important in intercellular communication. -Choose one: Cellulose, plasmodesmata, collagen, gap junctions, or tight junctions -Choose one: animal or plant

gap junctions, animal

The cleavage of glycogen by glycogen phosphorylase releases _____.

glucose-1-phosphate

Identify Structure A.

glycoprotein

A researcher made an interesting observation about a protein made by the rough endoplasmic reticulum and eventually found in a cell's plasma membrane. The protein in the plasma membrane was actually slightly different from the protein made in the ER. The protein was probably altered in the _____.

golgi apparatus

Which of the following sequences represents the order in which a protein made in the rough endoplasmic reticulum might move through the endomembrane system?

golgi apparatus, lysosome

What are some distinguishing characteristics that cilia and flagella has?

have a core composed of microtubules connected to the plasma membrane arranged in what is known as a 9 + 2 pattern.

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell they _____.

have no membrane-bounded organelles in their cytoplasm

Hormones are chemical substances produced in one organ that are released into the bloodstream and affect the function of a target organ. For the target organ to respond to a particular hormone, it must _____.

have receptors that recognize and bind the hormone molecule

The membranes of winter wheat are able to remain fluid when it is extremely cold by _____.

increasing the percentage of unsaturated phospholipids in the membrane

Several epidemic microbial diseases of earlier centuries incurred high death rates because they resulted in severe dehydration due to vomiting and diarrhea. Today they are usually not fatal because we have developed which of the following?

hydrating drinks with high concentrations of salts and glucose

the hydrophobic portionof a phospholipid is the

hydrophobic tail

This cell is in a(n) _____ solution.

hypertonic

greater concentration of solute outside the cell creates what kind of cell

hypertonic

Which variable is the independent variable--the variable that was controlled by the researchers? Is the independent variable on the x-axis or the y-axis?

incubation time; on the x-axis

Refer t o the figure. Initially, in terms of tonicity, the solution in side A with respect to the solution in side B is _____.

isotonic

You know that this cell is in a(n) _____ solution because it _____.

hypertonic solution ... lost water

crenation occurs in animal cells in what sort of solution

hypertonic, causes shrinking

a cell becoming turgid is a result of being placed in what kind of solution

hypotonic

You know that this cell is in a(n) _____ solution because the cell _____.

hypotonic ... swelled

hemolysis occurs in animal cells in what sort of solution

hypotonic, causes swelling

Click on the cell to start the animation. This plant cell is _____.

in a hypotonic solution

Chloroplasts and mitochondria are thought to be of prokaryotic origin. One piece of evidence that supports this hypothesis is that these organelles contain prokaryotic-like ribosomes. These ribosomes are probably most similar to ribosomes found _____.

in bacterial cells

Where can contracile vacuole be found and what does it do?

in many freshwater protists, and it pumps excess water out of cells

Where can a central vacuole be found and what does it do?

in many mature plant cells, and it holds organic compounds and water

The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized _____.

in the rough ER and in the golgi apparatus

SIgnal transduction pathways: -are necessary for signals to cross the membrane. -are only found in cases where the signal can cross the membrane. -include the extracellular events stimulated by an intracellular signal. -include the intracellular events stimulated by an extracellular signal.

include the intracellular events stimulated by an extracellular signal.

Which of the following increases the strength of the hydrophobic interactions in lipid bilayers and thus makes them less permeable to polar molecules?

increasing length of the hydrocarbon chains

The ______________ membrane receptor is connected to a ______________ element on the cytoplamic side of the membrane and leads to a rapid change in the shape of the cell when it's respective ligand is bound to the receptor site on the outside.

integrin, cytoskeletal

Scientists have found that extracellular matrix components may induce specific gene expression in embryonic tissues such as the liver and testes. For this to happen there must be direct communication between the extracellular matrix and the developing cells. Which kind of transmembrane protein would most likely be involved in this kind of induction?

integrins

homeostasis

internal equilibrium ; the plasma membrane regulates what enters and leaves the cell; a selectively permeable membrane only allows certain substances to pass through

Endocytosis moves materials _____ a cell via _____.

into ... membranous vesicles

Thyroid hormones bind to _____ receptors.

intracellular

Diffusion _____.

is a passive process in which molecules move from a region of higher concentration to a region of lower concentration

Celery stalks that are immersed in fresh water for several hours become stiff. Similar stalks left in a 0.15 M salt solution become limp. From this we can deduce that the fresh water_____.

is hypotonic and the salt solution is hypertonic to the cells of the celery stalks

Can you match these three tonicity terms with their descriptions?

iso hypo hyper hypo hyper iso

What does a perioxisome do?

it produces hydrogen peroxide and converts it to water

What is the purpose of the structure of the plant cell wall?

it protects the cell, maintains its shape, and prevents excessive uptake of water

Explain well cell fractionation is a useful technique.

it takes cells apart and separates the major organelles from one another. The isolated organelles can be used for determination of function. This would be the determination of proteins, lipids, enzyme activities, etc.

What is a food vacuole?

it's formed by phagocytosis. that means it's a process in which cell engulfs smaller organisms or other objects

What is the definition of a microtubule?

it's the thickest of the three components of the cytoskeleton.

What is the definition of a microfilament and what else might it be called?

it's the thinnest component of the three and is also called actin filament

The most common 'on' signal for activating proteins during the process of signal transduction is through the addition of a phosphate gourp by a _____________ enzyme.

kinase

How big is the Intermediate filament and what do they support?

larger than microfilament but smaller than microtubule and they support cell shape and fix organelles into place

A signal molecule is also known as a(n) _____.

ligand

cholesterol is a

lipid

steroids are

lipids

A sodium-potassium pump _____.

move three sodium ions out of a cell and two potassium ions into a cell while consuming an ATP for each cycle

Which of the following membrane activities requires energy from ATP?

movement of Na+ ions from a lower concentration in a mammalian cell to a higher concentration in the extracellular fluid

diffusion

movement of substances across the plasma membrane from areas of high concentration to areas of low concentration

active transports

movement of substances across the plasma membrane that requires the use of the cell's energy and carrier molecules; substances are moving from an area of low concentration to an area of higher concentration (against the concentration gradient)

passive transport

movement of substances across the plasma membrane without the use of the cell's energy (with the concentration gradient)

What type of cell is most likely to have the most mitochondria?

muscle cells in the legs of a marathon runner

The observation that chloroplasts and mitochondria each contain their own DNA and synthesize some of the proteins that function in these organelles suggests that chloroplasts and mitochondria _____.

must divide each time the cell containing them divides

Intercellular junctions facilitate what type of contact and how?

neighboring cells in tissues, organs, or organ systems often adhere, interact and communicate through direct physical contact

N-CAMs are primarily responsible for:

nerve growth during development

isotonic

no net movement; cell maintains equilibrium; solute concentration equal on both sides of a membrane

phospholipid tails are

nonpolar

what is the polarity of a lipid

nonpolar

A phospholipid is a _____.

nonpolar lipid molecule that is made amphipathic by the addition of a phosphate

What name is given to the process by which water crosses a selectively permeable membrane?

osmosis

the process by which water crosses a selectively permeable membrane

osmosis

Oxygen and carbon dioxide molecules move into and out of cells by

passive transport

Which of the following processes includes all others?

passive transport

The receptors for steroid hormones and peptide hormons are fundamentally different because: -of the great difference in size of the molecule. -peptides are hydrophilic (lipophobic) and steroids are hydrophobic (lipophilic) -peptides are hydrophobic (lipophilic) and steroids are hydrophilic (lipophobic) -peptides are one of the four major polymers and steroids are simple ringed structures.

peptides are hydrophilic (lipophobic) and steroids are hydrophobic (lipophilic)

Which of these are NOT embedded in the hydrophobic portion of the lipid bilayer at all?

peripheral proteins

Which of the following lack membranes as part of their structure?

peroxisomes & ribosomes

Which cell would be best for studying lysosomes?

phagocytic white blood cell

A white blood cell engulfing a bacterium is an example of _____.

phagocytosis

An organism with a cell wall would most likely be unable to take in materials through _____.

phagocytosis

Click on the brown debris to start the animation. This is an animation of _____.

phagocytosis

White blood cells engulf bacteria using _____.

phagocytosis

Drag the terms on the left to the appropriate blanks on the right to complete the sentences.

phosphate group choline group hydrophilic fatty acid hydrophobic

phospholipids are

phosphate lipids

Identify Structure D.

phospholipid bilayer of membrane

Click on the extracellular fluid to start the animation. You know that this process is _____ because _____.

pinocytosis ... the cell is engulfing extracellular fluid

The difference between pinocytosis and receptor-mediated endocytosis is that _____.

pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity.

This structure may have multiple layers like: a primary cell wall-relatively thin and flexible, a middle lamella-thin layer between primary walls of adjacent cells, and secondary cell wall-added between the plasma membrane and the primary cell wall

plant cell wall

What has plasmodesmata and what does it do?

plants and it allows water and small solutes (and sometimes proteins and RNA) can pass from cell to cell

A substance moving from outside the cell into the cytoplasm must pass through _____.

plasma membrane

One characteristic of life and living systems is that they are able to adapt. Toward this end, cells interact with other cells and their environment through the action of their _______.

plasma membrane and extracellular matrix

Dye injected into a plant cell might be able to enter an adjacent cell through _____.

plasmodesmata

Small channels between cells that are otherwise surrounded by walls; enable movement of water and solutes between cells. -Choose one: Cellulose, plasmodesmata, collagen, gap junctions, or tight junctions -Choose one: animal or plant

plasmodesmata, plant

phospholipid heads are

polar

what is the polarity of sugar

polar

The hydrophilic, or water-loving, portion of a phospholipid is the

polar head

What are the main functions that Rough ER does?

produces proteins and membranes, makes secretory protein & is a membane factory for the cell

The extracellular matrix is composed mainly of _______, which are made on the _______ of the cell.

protein fibers, endomembrane system

The function of a _________ is to add phosphates to proteins, whereas a _______ functions to remove the phosphates.

protein kinase, protein phosphate

Which answer correctly identifies a character from this scene with a component involved in signal transduction as shown in the figure below?

queen = G protein

What is the definition of magnification?

ratio of image to its actual size

Label as either reception, transduction, or response: -adenylyl cyclase -IP3 -signaling molecule -second messenger -protein synthesis -cAMP -receptor tyrosine kinase -phosphorylation cascade -Ca2+ -G protein-coupled receptor

reception: signaling molecule, G protein-coupled receptor, receptor tyrosine kinase transduction- adenylyl cyclase, cAMP, Ca2+, IP3, phosphorylation cascade, second messenger response- protein synthesis

Click on the receptor protein to start the animation. This is an animation of _____.

receptor-mediated endocytosis

Which of the following enables a cell to pick up and concentrate a specific kind of molecule?

receptor-mediated endocytosis

Which of the following is present in a prokaryotic cell?

ribosome

Which of the following groups is primarily involved in synthesizing molecules needed by the cell?

ribosome, rough endoplasmic reticulum, smooth endoplasmic reticulum

Which of the following organelles might be found inside other organelles?

ribosomes

Which of the following features do prokaryotes and eukaryotes have in common?

ribosomes, plasma membrane, cytoplasm

A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized _____.

rough ER

You would expect a cell with an extensive Golgi apparatus to _____.

secrete a lot of protein

Refer to the figure. At the beginning of the experiment,

side A is hypotonic to side B.

A signal transduction pathway is initiated when a _____ binds to a receptor.

signal molecule

You are working on a team that is designing a new drug. For this drug to work, it must enter the cytoplasm of specific target cells. Which of the following would be a factor that determines whether the molecule selectively enters the target cells?

similarity of the drug molecule to other molecules transported by the target cells

What kinds of molecules pass through a cell membrane most easily?

small and hydrophobic

Structure A is a _____.

solute

hypotonic

solute concentration higher inside of cell, solvent concentration higher outside of the cell; therefore water moves in

hypertonic

solute concentration higher outside of the cell, solvent concentration higher inside of the cell; therefore water moves out

What is the function of Structure E?

stabilization of the phospholipids

A(n) _____ is an example of a signal molecule that can bind to an intracellular receptor and thereby cause a gene to be turned on or off.

steroid

The force driving simple diffusion is _____, while the energy source for active transport is _____.

the concentration gradient; ATP

What do the blue dots represent?

the concentration of radioactive glucose found in a 1-month-old guinea pig's red blood cells after different incubation times

What do the red dots represent?

the concentration of radioactive glucose found in a 15-day-old guinea pig's red blood cells after different incubation times

Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why?

the intestinal cells are bound together by tight junctions

solvent

the material in which solute(s) are dissolved forming a solution

What is the difference between the rods of the microtubule and the microfilament?

the microtubule are hollow and the other is solid

photosynthesis

the process in green plants and certain other organisms in which glucose is synthesized from carbon dioxide and water using light as an energy source; releases oxygen as a byproduct

What does the endomembrane system regulate?

the protein traffic and performs metabolic functions in the cell

turgor

the rigid or fullness state of a cell due to high water content

What is the function of a microtubule?

the shaping of the cell, guiding movement of organelles, and separating chromosomes during cell division

You are working on a team that is designing a new drug. For this drug to work, it must enter the cytoplasm of specific target cells. Which of the following would be a factor that determines whether the molecule selectively enters the target cells?

the similarity of the drug molecule to other molecules that are transported into the target cells

Where can cilia and flagella be found?

the sperm of many animals, algae, and even ferns

light independent reaction

the stage of photosynthesis in which energy, produced from the light dependent reaction, is used to convert carbon dioxide into glucose; occurs in the stroma of the chloroplast

light dependent reaction

the stage of photosynthesis in which plants capture and store energy from sunlight

solute

the substances that is dissolved in a solution; ex: is salt water, where water is the solvent and salt is the solute

What region of a steroid is hydrophilic?

the terminal hydroxyl group

The permeability of a biological membrane to a specific polar solute may depend on which of the following?

the types of transport proteins in the membrane

Ions diffuse across membranes through specific ion channels down _____.

their electrochemical gradients

Where are bound ribosomes located?

they're attached to the outer surface of the endoplasmic reticulum (ER)or the nuclear envelope

Water crosses the plasma membrane

through facilitated diffusion or diffusion.

The Chloroplast structure includes what?

thylakoids, membranous sacs, stroma & the internal fluid

A cell junction found in the epithelium lining the bladder would most likely be a _______

tight junction