BIO110 PRACTICE EXAM 2.1

Penicillin is toxic to certain dividing bacterial cells because it prevents cell wall formation, causing the cells to burst. This indicates that the bacteria live in: a. a hypotonic medium b. a hypertonic medium c. an isotonic medium d. a medium with a higher osmotic pressure than the cell e. both a hypertonic medium and a medium with a higher osmotic pressure than the cell

a. a hypotonic medium

A bacterium containing sodium ions at a concentration of 0.1 mM lives in a pond that contains sodium ions at 0.005 mM. Evidently, sodium ions are entering the cell by: a. active transport b. endocytosis c. diffusion d. facilitated diffusion e. osmosis

a. active transport

A cellular structure found in plant but not animal cells is the: a. chloroplast b. ribosome c. endoplasmic reticulum d. microtubule e. microfilament

a. chloroplast

The theory that chloroplasts and mitochondria had their evolutionary beginnings in eukaryotic cells as endosymbionts is supported by all of the following EXCEPT: a. chloroplasts and mitochondria are completely autonomous within eukaryotic cells b. chloroplasts and mitochondria have DNA c. chloroplasts and mitochondria have small ribosomes for protein synthesis d. chloroplasts and mitochondria have approximately the same size as prokaryotic cells e. chloroplasts and mitochondria have the same shape as prokaryotic cells

a. chloroplasts and mitochondria are completely autonomous within eukaryotic cells

Biological membranes are generally permeable to ions: a. false b. true

a. false

Dynamic equilibrium means that the rates of movement are different a. false b. true

a. false

If the concentration of solutes in a cell is less than the concentration of solutes in the surrounding fluid, then the extracellular fluid is said to be: a. hypertonic b. hypotonic c. isotonic d. stable e. amphipathic

a. hypertonic

If a blood cell is placed in a solution and swells it is in response to a __________ solution, while if a blood cell is placed in a solution and shrinks it is in response to a __________ solution. a. hypotonic; hypertonic b. hypertonic, hypotonic c. isotonic; isotonic d. hypohypertonic; hyperhypotonic e. tonic; sonic f. hydrotonic; aquatonic g. aquatonic, hydrotonic

a. hypotonic; hypertonic

An example of a signaling molecule that binds with a receptor on the cell surface is: a. insulin b. ecdysone c. Vitamin D d. Vitamin A e. nitric oxide

a. insulin

A mitochondrion's spaces between the membranes are: a. intermembrane space (outer) and matrix (inner) b. intermembrane space (inner) and matrix (outer) c. none of the above

a. intermembrane space (outer) and matrix (inner)

The ratio of the size of the image seen with the microscope to the actual size of the object is called: a. magnification b. resolution c. resolving power d. centrifugation e. fractionation

a. magnification

If a toxin, such as a bacterial toxin, destroys ribosomes, what cellular activity will be affected first?: a. protein synthesis b. DNA synthesis c. movement d. energy storage e. active transport

a. protein synthesis

Membrane-bounded organelles facilitate faster chemical reactions because: a. reactants are within close proximity to each other b. membranes lower thee activation energy of biochemical reactions c. membrane-bound organelles act as catalysts for biochemical reactions d. reactants are less likely to encounter each other within membrane-bound organelles

a. reactants are within close proximity of each other

Facilitated diffusion: a. requires a transmembrane protein b. requires ATP c. can move molecules against a concentration gradient d. is typically used to transport small nonpolar molecules e. is typically used to transport large food particles

a. requires a transmembrane protein

Which of the following statements explaining the differences in number and types of peripheral proteins found on the inner and outer surfaces of cell membranes is correct?: a. the functions of the membrane differ on the inside and outside of the cell b. not all proteins can pass through the membrane and, thus, more accumulate on the inside c. proteins on the outside of the membrane are synthesized at a slower rate than proteins on the inside of the membrane d. proteins on the outside of membrane are made extracellularly and are unable to penetrate the phospholipid bilayer and enter the cell e. the external peripheral proteins are weakly attached to the membrane and are readily washed away

a. the functions of the membrane differ on the inside and outside of the cell

Which of the following statements explaining the differences in number and types of peripheral proteins found on the inner and outer surfaces of cell membranes is correct?: a. the functions of the membrane differ on the inside and outside of the cell b. not all proteins can pass through the membrane, and thus, more accumulate on the inside. c. proteins on the outside of the membrane are synthesized at a slower rate than proteins on the inside of the membrane d. proteins on the outside of membrane are made extracellularly and are unable to penetrate the phospholipid bilayer and enter the cell e. the external peripheral proteins are weakly attached to the membrane and are readily washed away

a. the functions of the membrane differ on the inside and outside of the cell

A concentration gradient contains two regions, one with high and the other with low concentration, and provides potential energy that can be used to move substances from one side to another: a. true b. false

a. true

A ligand is a signaling molecule that generally binds to specific macromolecules (proteins/enzymes): a. true b. false

a. true

ABC transporters are types of carrier proteins that uses ATP to transfer ions or sugars or polypeptides: a. true b. false

a. true

Active transport requires chemical energy to pump solutes across a membrane: a. true b. false

a. true

Aerobic respiration can be described by a redox process whereby a catabolic reaction from sugar and oxygen to produce water and carbon dioxide: a. true b. false

a. true

An example of active transport is the Na+/K+ pump: a. true b. false

a. true

Aquaporins are types of channel proteins that are gated and allow water through to facilitate rapid transport: a. true b. false

a. true

Biological membranes are generally impermeable to polar molecules: a. true b. false

a. true

Biological membranes are made mostly of phospholipids: a. true b. false

a. true

Centrioles have 9x3 structure: a. true b. false

a. true

Channel proteins form tunnels in the membrane that allow them to allow certain substances through: a. true b. false

a. true

Cristae in mitochondria increase the surface area of the inner mitochondrial membrane: a. true b. false

a. true

Desmosomes are a type of anchoring junction that "spot-weld" adjacent animal cells together connections between protein filaments between two cells: a. true b. false

a. true

Dynamic equilibrium means that the rates of movement are equal: a. true b. false

a. true

Dynein is used with MAPs (Microtubule associated proteins) to move cell towards the negative end of microtubule: a. true b. false

a. true

Endocrine glands are ductless glands that secrete hormones in surrounding interstitial fluid, which diffuse into blood stream and carried to target cells: a. true b. false

a. true

Fatty acids are generally are hydrophobic: a. true b. false

a. true

Flagella are involved in motility: a. true b. false

a. true

G protein coupled receptors are a large family of transmembrane proteins that contain 7 transmembrane helices: a. true b. false

a. true

G proteins are found in all eukaryotes: a. true b. false

a. true

Gap junctions are composed of connexin protein annd forms channels that allow freely flowing cytoplasm between adjacent cells: a. true b. false

a. true

Histamine is a local regulating neurotransmitter stored in cells of immune system and released in response to allergy, injury, or infection: a. true b. false

a. true

Hormones are signaling molecules generally produced by endocrine glands: a. true b. false

a. true

Hydrophilic means water loving: a. true b. false

a. true

Hypertonic means that something is more concentrated than its reference: a. true b. false

a. true

Hypotonic means that something is less concentrated than its referance: a. true b. false

a. true

Interstitial fluid is the fluid surrounding cells and acts on nearby cells: a. true b. false

a. true

Isotonic means that the solution outside and inside the cell is at equilibrium with respect to salt concentration: a. true b. false

a. true

Kinases are enzymes that transfer the terminal phosphate from ATP to a substrate in the process of phosphorylation: a. true b. false

a. true

Kinesin is used with MAPS (Microtubule associated proteins) to move organelles toward the positive end of the microtubule: a. true b. false

a. true

Lysosomes are compartments for digestion: a. true b. false

a. true

Mitochondria contain a double membrane: a. true b. false

a. true

Mitochondria synthesize ATP through cellular respiration: a. true b. false

a. true

Most intracellular receptors are transcription factors that regulate the expression of specific genes: a. true b. false

a. true

Neurotransmitters are chemical compounds that act as signaling molecules: a. true b. false

a. true

Nitric oxide (NO) is a local regulator signaling molecule gas produced to relax smooth muscle in blood vessel walls causing dilating of blood vessels and decreasing blood pressure: a. true b. false

a. true

Paracrine signaling is when a local regulator signal diffuses through interstitial fluid to interact with adjacent cells: a. true b. false

a. true

Peripheral membrane proteins are not imbedded in the membrane bilayer and associated on either the inner or the outer surface: a. true b. false

a. true

Phytochromes are a family of blue-green pigment proteins activated by red light, and activating phytochromes may cause flowering: a. true b. false

a. true

Plasmodesmata are channels connecting adjacent plant cells and allow ions, , small molecules and larger molecules through: a. true b. false

a. true

Prostaglandins are local hormone paracrine regulators that modify cAMP levels and interact with other signaling molecules to regulate metabolism: a. true b. false

a. true

Receptor mediated endocytosis occurs when specific receptors coated pits of clathrin on a cell membrane bind with ligand molecules to form coated vesicles, so then vesicles fuse with lysosomes and contents are digested and released into cytosol: a. true b. false

a. true

Ribosomes are made of RNA + proteins and are synthesizes by nucleolar regions: a. true b. false

a. true

Scaffolding proteins organize groups of intracellular signaling molecules into signaling complexes to make a physical framework and guide movement of molecules to targets: a. true b. false

a. true

Selectively permeable membranes let all substances through: a. true b. false

a. true

Selectively permeable membranes let some substances through, others not and are therefore temporarily selective due to environmental conditions: a. true b. false

a. true

The cell membrane consists of a fluid bilayer, where phospholipid molecules have proteins embedded, and the proteins and phospholipids are in constant motion like icebergs in water. a. true b. false

a. true

The mitotic spindle serves as a framework for orderly distribution of chromosomes during cell division: a. true b. false

a. true

The most stable orientation of the phospholipid bilayer exists to decrease the potential energy between molecular attractions between repelling particles so that hydrophobic ends are embedded within the bilayer, and hydrophilic ends are exposed to water on the surfaces: a. true b. false

a. true

The phosphate part of a phospholipid is the hydrophilic end: a. true b. false

a. true

Transmembrane proteins extend through the membrane: a. true b. false

a. true

Turgor pressure is the pressure that builds up to make rigid cell walls (in plants) when a vacuole absorbs water, excreting a pressure on the cell walls: a. true b. false

a. true

Vitamin A, D and Nitric Oxide bind to intracellular receptors: a. true b. false

a. true

Tight junctions seal membranes of adjacent cells so that they prevent substances from moving between cells: a. true

a. true b. false

Adenylyl cyclase catalyzes the reaction in which: a. a protein is phosphorylated b. ATP is converted to cAMP c. GTP is converted to GDP d. PIP2 is split e. calcium ions bind calmodulin

b. ATP is converted to cAMP

A protein kinase catalyzes the reaction in which: a. a protein loses a phosphate group b. a protein is phosphorylated c. G protein is activated d. ATP is converted to cAMP e. GTP is converted to GDP

b. a protein is phosphorylated

The cis face of the Golgi complex is most directly involved in which of the following?: a. packaging molecules in vesicles b. accepting vesicles from the ER c. synthesizing proteins d. transporting molecules out of the Golgi e. catalyzing the efficient folding of proteins

b. accepting vesicles from the ER

An example of a neurotransmitter that opens ligand-gated sodium channels is: a. GABA b. acetylcholine c. ecdysone d. NO e. cortisol

b. acetylcholine

Which of the following structures would not be found in cells of a plant's roots? a. mitochondria b. chloroplasts c. endoplasmic reticulum d. nucleus e. Golgi complex

b. chloroplasts

Biological membranes are permeable to large polar molecules: a. true b. false

b. false

Exocytosis and endocytosis requires no chemical energy to be used: a. true b. false

b. false

Hydrophobic means water loving: a. true b. false

b. false

Isotonic means that the solution outside and inside the cell are very different with respect to their concentrations: a. true b. false

b. false

Phagocytosis is cell drinking: a. true b. false

b. false

Pinocytosis is cell eating: a. true b. false

b. false

The mitotic spindle is a vestigial component of mitosis: a. true b. false

b. false

Hormones produced by endocrine glands are typically transported to target cells: a. across a synapse b. in the blood c. in interstitial fluid d. via direct contact e. through the air

b. in the blood

What is meant by the term "fluid mosaic model?" a. it is the diffusion of lipid-soluble substances through the lipid bilayer b. it is the movement of lipids and integral proteins within the lipid bilayer c. it is the solubility of water in the membrane d. it is the method of substance transport across the membrane e. it is the movement of surface proteins through the membrane

b. it is the movement of lipids and integral proteins within the lipid bilayer

Select the receptor mediated endocytosis events that are in the correct (before, after) order: a. endosome fuseses with lysosome; receptors are transported to plasma membrane and recycled b. ligand binds to receptors; coated vesicle forms by endocytosis c. contents are digested and released in the cyclotone; ligand separtes from its receptor d. endosome fuses with lysosome; receptors are transported to plasma membrane and recycled e. None are correct

b. ligand binds to receptors; coated vesicle forms by endocytosis

Which of the following is a key component of the cytoskeleton?: a. centrosome b. microtubules c. DNA d. ribosomes e. endoplasmic reticulum f. Golgi apparatus

b. microtubules

Which of the following organelles plays an important role in apoptosis, or programmed cell death? a. ribosomes b. mitochondria c. chloroplasts d. vacuoles e. peroxisomes

b. mitochondria

Nucleoli contain chromosomal regions that specialize in making: a. proteins b. ribosomal RNA c. ribosomes d. lipids e. hormones

b. ribosomal RNA

Simple diffusion may involve the movement of ________ through the plasma membrane down a concentration gradient: a. small polar molecules b. small nonpolar molecules d. small multipolar molecules e. large polar molecules f. large nonpolar molecules e. water

b. small nonpolar molecules

Studies of glucose transport in liposomes have revealed that: a. glucose is transported against a concentration gradient b. the binding of glucose triggers a conformation change in the carrier protein c. the transport of solutes via carrier proteins is faster than via channel proteins d. glucose phosphates move readily across the membrane by simple diffusion e. glucose moves readily across the membrane by simple diffusion

b. the binding of glucose triggers a conformational change in the carrier protein

Microtubules are negatively charged on one and and positively charged on one end. It is also true that: a. the negative end elongates faster b. the positive end elongates faster c. both ends elongate at the same rate d. none of the above

b. the positive end elongates faster

ATP is like chemical currency that a cell can use as fuel: a. false b. true

b. true

Ribosomes in mitochondria and chloroplasts are similar to prokaryotic ribosomes: a. false b. true

b. true

An ABC transporter: a. is a typer of water channel b. uses the energy of ATP to transport solutes c. uses gated channels to transport ADP d. is present in kidney tubules and prevents dehydration e. is a type of porin

b. uses the energy of ATP to transport solutes

The _________ can be considered a sorting, processing and packaging center. a. centriole b. centrosome c. Golgi complex d. vacuole e. cytoskeleton

c. Golgi complex

You isolate a cellular structure and determine that it is composed of alpha-tubulin and beta-tubulin. Basd on this evidence, you correctly identify this structure as: a. a structural MAP b. a microfilament c. a microtubule d. an actin filament e. a myosin filament

c. a microtubule

It is advantageous for cells to be small because: a. a small cell size prevents a cell from weighing too much b. a small cell size occupies less space in nature where space is limited c. a small cell has a small volume relative to surface area, thereby increasing efficient transport d. a small cell has a small surface area relative to volume, thereby facilitating ion balance e. a small cell is better able to conserve energy than a large cell

c. a small cell has a small volume relative to surface area, thereby increasing efficient transport

It is advantageous for cells to be small because: a. a small cell size prevents a cell from weighing too much b. a small cell size occupies less space in nature where space is limited c. a small cell has a small volume relative to surface area, thereby increasing efficient transport d. a small cell has a small surface area relative to volume, thereby facilitating ion balance e. a small cell is better able to conserve energy than a larger cell

c. a small cell has a small volume relative to surface area, thereby increasing efficient transport

Quorum sensing would most likely occur when: a. Dictyostelium senses cyclic AMP b. tobacco plants are attacked by insects c. bacteria reach a certain critical concentration d. predator insects eat herbivorous insectss e. insulin binds to target cells

c. bacteria reach a certain critical concentration

All of the following are functions of the cell membrane EXCEPT: a. transmitting signals b. participating in energy transfer c. being freely permeable to all substances d. regulating the passage of materials e. participating in chemical reactions f. none of the above

c. being freely permeable to all substances

The basal body is most closely related to a: a. ribosome b. thylakoid c. centriole d. centrosome e. lysosome

c. centriole

Which of the following pairs is correctly matched?: a. chloroplasts-storage of enzymes b. lysosome-powerhouse of the cell c. centrosome-cell division d. plastids-structural support of the cell e. Golgi complex-production of energy

c. centrosome-cell division

The main process that occurs at the site of the organelle that produces energy is: a. protein synthesis b. photosynthesis c. conversion of food molecules to ATP d. processing and packaging of proteins e. transcription

c. conversion of food molecules to ATP

The inner membrane of mitochondrion contains: a. chloroplasts b. chlorophyll c. cristae d. crystalline e. crysanthmae

c. cristae

An example of a second messenger is: a. protein kinase A b. an ion channel c. cyclic AMP d. GABA e. insulin

c. cyclic AMP

The passive movement of a substance along its concentration gradient is termed: a. active transport b. dialysis c. diffusion d. exocytosis e. osmosis

c. diffusion

One strategy that allows larger cells to have an effective surface area to volume ratio is: a. having a completely spherical shape b. being short and fat c. having thin, finger-like projections d. having a thinner plasma membrane e. locomotion

c. having thin, finger-like projections

A wilted flower placed in a vase of water for several hours became stiff and stood erect. When it was placed in a salt solution, it wilted. From this information we can say that the cells of the flower are a. hypotonic to both fresh water and the salt solution b. hypertonic to both the fresh water and the salt solution c. hypertonic to fresh water but hypotonic to the salt solution d. hypotonic to fresh water but hypertonic to the salt solution e. isotonic to fresh water but hypotonic to the salt solution

c. hypertonic to fresh water but hypotonic to the salt solution

Proteins are destined to become associated with the inner surface of the plasma membrane are: a. manufactured the same way as protein hormones b. manufactured in the same way as proteins destined to become external peripheral proteins c. made on free ribosomes in the cytoplasm d. made on ribosomes located on the rough ER e. transported to the plasma membrane within a secretory vesicle

c. made on free ribosomes in the cytoplasm

A human white blood cell engulf's a bacterial cell by: a. carrier-mediated facilitated diffusion b. exocytosis c. phagocytosis d. pinocytosis e. the sodium-potassium pump

c. phagocytosis

Integrins are unusual in that they: a. are steroids b. are specific transmembrane proteins c. respond to information received from inside and outside the cell d. stimulate both the RAS pathway as well as the IP3 pathway e. are found only in Arabidopsis thaliana

c. respond to information received from inside and outside the cell

Nucleoli contain chromosomal regions that specialize in making: a. proteins b. RNA c. ribosomes d. lipids e.hormones

c. ribosomes

Which of the following structures or activities is NOT directly part of the endomembrane system?: a. budding b. lysosomes c. ribosomes d. peroxisomes e. Golgi complex

c. ribosomes

Which of the following is NOT an example of an enzyme-linked receptor?: a. a tyrosine kinase b. the brassinolide receptor c. the GABA receptor d. the ethylene receptor e. a histidine kinasee

c. the GABA receptor

Which of the following statements concerning receptors is FALSE? a. they are found inside the cell on the cell surface b. they are proteins or glycoproteins c. they are also called ligands d. they are highly selective e. they are activated by binding to a signaling molecule

c. they are also called ligands

Which of the following statements concerning intracellular receptors is FALSE?: a. some bind hydrophobic signaling molecules b. some function as transcription factors c. they diffuse across the plasma membrane of target cells d. the ligand-receptor complex can activate genes e. the ligand-receptor complex can inactivate genes

c. they diffuse across the plasma membrane of target cells

Which of the following statements concerning centrioles is FALSE?: a. they are present in most animal cells but not most plant cells b. they are duplicated before cell division c. they have a 9+2 arrangement of microtubules d. they are found in the centrosome e. they are though to play a role in microtubule assembly

c. they have a 9+2 arrangement of microtubules

In the experiment in which Frye and Edidin fused the plasma membranes of a mouse and a human cell, what happened to the membrane proteins?: a. they formed a spherical structure b. they formed a bilayer c. they moved laterally across the cell surface d. they flip-flopped from one layer to the other e. they reacted with cholesterol molecules on the membrane surface

c. they moved laterally across the cell surface

a plant cell placed in a hypertonic solution will: a. remain unchanged b. undergo lysis c. undergo plasmolysis d. swell slightly e. become crenated

c. undergo plasmolysis (non plants crenate)

Proteins are made on ribosomes may be further modified within the: a. lysosomes b. nucleus c. mitochondria d. Golgi complex e. peroxisomes

d. Golgi complex

Brassinosteroids are a group of plant steroid hormones that regulate plant processes including: a. cell division b. elongation c. inflorescence d. a, b and c e. none of the above f. a and b g. a and c

d. a, b and c

Which of the following statements concerning intracellular receptors is FALSE? a. their ligands are hydrophobic b. most are transcription factors c. some are located in the cytosol d. after binding their ligand they move out of the cell e. some are bound to DNA

d. after binding their ligand, they move out of the cell

Ethylene gas is a plant hormone that regulates processes including: a. germination b. ripening fruit c. stress signaling d. all of the above

d. all of the above

Lysosomes: a. have a pH~5 interior b. can damage the host cell if they leak c. contain hydrolytic enzymes d. all of the above

d. all of the above

Membrane proteins include: a. integral membrane proteins b. transmembrane proteins c. peripheral membrane proteins d. all of the above

d. all of the above

Evidence that all living cells have a common origin is provided by: a. the cell theory, which states that the cell is the basic unit of life b. the fact that lal new cells come from previously existing cells c. the fact that cells are the building blocks of the most complex plants d. basic similarities in structure and chemistry e. the fact that cells are the smallest units that can carry out all life activities

d. basic similarities in structure and chemistry

A transmembrane protein differs from other membrane proteins because it: a. is covalently linked to the outer surface of the plasma membrane b. is a glycoprotein with carbohydrates attached c. is attached to the inside of the membrane by an ionic bond d. completely extends through the membrane e. is completely embedded within the membrane

d. completely extends through the membrane

The force necessary to cause microtubules of cilia and flagella to slide alongside one another is provided through the action of _______ proteins, which derive the energy to perform their work directly from _________ molecules: a. kinesin; ADP b. kinesin; glucose c. tubulin; ATP d. dynein, ATP e. dynein, ADP

d. dynein, ATP

In contrast to a G-protein linked receptor and an enzyme-linked receptor, a channel-linked receptor: a. is located on the cell surface b. is composed of seven alpha helices c. couples signaling molecules to signal transduction pathways d. is a ligand-gated channel e. functions as a tyrosine kinase

d. is a ligand-gated channel

Which of the following molecules is least likely to cross a cellular membrane by simple diffusion?: a. carbon dioxide b. nitrogen c. oxygen d. potassium ion e. water f. ammonia

d. potassium ion

The smooth endoplasmic reticulum: a. is absent in most plant cells b. synthesizes proteins c. provides structural support d. synthesizes lipids e. is required for ribosome synthesis

d. synthesizes lipids

A person has a genetic disease that prevents the phospholipids in the plasma membrane of the white blood cells from freely fusing with the other membranes within the cell. How would this disease affect phagocytosis?: a. lysosomes would not be formed b. facilitated diffusion would not occur c. lysosomes would be formed lacking hydrolytic enzymes d. the phagotcytic vacuole would not fuse with the lysosome e. endocytosis would not occur

d. the phagocytic vacuole would not fuse with the lysosome

When a receptor binds to its G protein, which of the following happens next? a. the signaling molecule binds to the receptor b. the G protein activates an enzyme c. the three G protein subunits come together d. GTP is replaced by GDP e GP is replaced by GTP

e. GDP is replaced by GTP

Peroxisomes: a. are membrane-enclosed organelles with enzymes that catalyze an assortment of metabolic reactions b. are membranes within a vacuole c. are important for turgor pressure d. detoxify toxic substances in human liver e. a and d

e. a and d

Paracrine signaling is different from other types of signaling in that the signaling molecule: a. is produced by endocrine glands b. binds to a receptor c. is secreted by neurons d. is transported in the blood e. acts on nearby cells

e. acts on nearby cells

Passive transport includes: a. diffusion b. simple diffusion c. osmosis d. facilitated diffusion e. all but f f. active transport

e. all but f

Cytoskeleton: a. gives cells mechanical strength, shape, motility b. helps in cell division c. helps in the transport of materials d. contains microtubules and microfilaments e. all of the above

e. all of the above

Intermediate filaments: a. are of intermediate size (10nm) b. are composed of fibrous proteins like keratin c. have the ability to bend/twist and provide resistance to mechanical stress d. provide framework for the cell and to anchor organelles e. all of the above

e. all of the above

The Golgi complex: a. sort and modifies proteins b. synthesizes extracellular polysaccharides c. synthesizes lysosomes d. has a cis and a trans face e. all of the above

e. all of the above

The Rough ER: a. is studded with bound ribosomes b. is involved in the synthesis of proteins c. contains molecular chaperones d. produces transport vesicles e. all of the above

e. all of the above

The phospholipid bilayer behaves as: a. liquid crystals b. having free movement by rotation and can move laterally (2D movement) c. having moving molecules in ever changing configurations d. semipermeable membrane e. all of the above

e. all of the above

Integral proteins: a. are weakly bound to the surface of the membrane b. are strongly bound to the cytosolic surface of the membrane c. have no hydrophobic portions d. are completely embedded within the lipid bilayer e. are amphipathic

e. are amphipathic

Vegetable oil is different from animal fat in that the phospholipids in vegetable oil have fatty acid tails that: a. solidify at room temperature b. lack double bonds c. are saturated d. interact via van der Waals forces e. bend

e. bend

A receptor on the cell surface usually has several domains. The function of the external domain is: a. transmitting the signal to the inside of the cell b. holding the receptor within the membrane c. attaching the receptor to the DNA d. functioning as an enzyme e. binding the signaling molecule

e. binding the signaling molecule

Which of the following are forms of carrier-mediated transport? a. facilitated diffusion only b. carrier-mediated active transport only c. osmosis only d. both facilitated diffusion and carrier-mediated active transport e. facilitated diffusion, carrier-mediated active transport, and osmosis

e. both facilitated diffusion and carrier-mediated active transport

DNA is associated with proteins, forming a complex called: a. chromosomes b. nucleoli c. nucleus d. genes e. chromatin

e. chromatin

One function of peroxisomes involves the process of: a. cell death b. water storage c. protein synthesis d. DNA replication e. detoxification

e. detoxification

Cholesterol within membranes functions as a(n) ___________ through its interactions with both hydrophobic and hydrophilic parts of phospholipids: a. water blocker b. pH buffer c. energy source d. temperature controller e. fluidity buffer

e. fluidity buffer

A eukaryotic cell: a. is usually smaller than a prokaryotic cell b. has its DNA concentrated in one area of the cell without a nuclear membrane c. typically has a cell wall, in addition to a plasma membrane d. is exemplified by bacteria e. has a variety of membraneous organelles

e. has a variety of membraneous organelles

The organelle that produces energy in a eukaryotic cells is the: a. ribosome b. nucleoli c. nucleus d. nuclear membrane e. mitochondrion f. rough ER g. smooth ER h. cytoskeleton network i. chloroplasts

e. mitochondrion

Which of the following lists the correct sequence of events involved in cell signaling? a. amplifying, signal transducing, receiving, responding b. signal transducing, sending, receiving, terminating c. sending, signal transducing, receiving, amplifying d. receiving, sending, signal transducing, responding e. sending, receiving, signal transducing, responding

e. sending, receiving, signal transducing, responding

Which of the following descriptions of structures does NOT match the cell type?: a. sperm cells have flagella b. nerve cells have long thin extensions c. epithelial cells are rectangular d. white blood cells can change shape e. smallest cells are egg cells

e. smallest cells are egg cells

Consider a U-tube that initially contains pure water on one side of a selectively permeable membrane and water plus solute on the other side. Which of the following best describes what will happen next?: a. solute molecules diffuse across the membrane faster than water molecules b. the fluid level rises on the side containing the pure water c. the diffusion of water molecules causes an osmotic pressure to build up in the tube d. solute molecules are transported across the membrane by facilitated diffusion e. some water molecules become "bound up" with solute molecules and do not diffuse freely

e. some water molecules become "bound up" with solute molecules and do not diffuse freely

All of the following functions are performed by plant vacuoles EXCEPT: a. maintaining hydrostatic (turgor) pressure b. waste storage and recycling c. storage of proteins d. breakdown of uneeded cellular materials e. storage of nucleic acids

e. storage of nucleic acids

In the cAMP signal transduction pathway, once a protein kinase is activated, which of the following happens next?: a. G protein is activated b. adenylyl cyclase is activated c. GDP is replaced by GTP d. cAMP is converted to ATP e. the protein kinase activates a cellular response

e. the protein kinase activates a cellular response

Which of the following statements concerning phospholipids is FALSE?: a. they have two distinct regions, one strongly hydrophobic and the other strongly hydrophilic b. they are amphipathic molecules c. they have cylindrical shapes that allow them to associate with water most easily as a bilayer structure d. they contain a polar organic group attached to a phosphate group e. they contain three fatty acid chains g. they contain two fatty acid chains

e. they contain three fatty acid chains

The functions of biological membranes includes: a. to regulate the passage of materials b. divide cell into compartments c. act as a reaction surface d. important in cell communication e. important in energy transfer and storage f. all of the above

f. all of the above

Vacuoles are associated with: a. plant volume b. turgor pressure c. food and salt storage d. metabolic waste storage e. maintaining pH balance f. all of the above

f. all of the above

The Smooth ER: a. synthesizes steroid hormones b. synthesizes phospholipids c. synthesizes cholesterol d. stores calcium e. important in detoxification f. synthesizes various lipids and carbohydrates g. contain no ribosomes h. all of the above

h. all of the above

Which of the following membrane activities does not require the expenditure of energy by the cell?: a. active transport b. osmosis c. endocytosis d. exocytosis e. synthesis of more membrane f. pinocytosis g. phagocytosis h. facilitated diffusion i. b and h j b, h and c k. all of the above

i. b and h, osmosis and facilitated diffusion