CHAPTER 2 /Chapter 3
A(n) _____is an arrangement of atoms found in a variety of macromolecules? 1) stereoisomer 2) isotope 3) functional group 4) buffer 5) salt
3) functional group
15) Another name for a channel protein in the cell membrane is __________.
Answer: permease
7) Eukaryotic cells use a process known as __________ to obtain liquids from their environment.
Answer: pinocytosis
4) A(n) __________ is a carrier protein that transports two substances in the same direction across a membrane.
Answer: symport
14) A structural molecule found in eukaryotic cytoskeletons, flagella, cilia, and centrioles is __________.
Answer: tubulin
2) The presence of a cell __________ enables bacterial and plant cells to resist the effects of hypotonic solutions.
Answer: wall
Which type of active transport protein uses one protein to pump two different molecules?
Antiport and Symport
__________ may have flagella.
Archaea, bacteria, and eukaryotes
Which of the following would require the use of a protein channel to assist in transport into and out of the cell? dissolved oxygen water simple alcohols hydrophobic molecules
hydrophobic molecules
The valence of an atom represents
its ability to interact with other atoms.
Which of the following molecules would be blocked by a cell membrane?
Ions
Which of the following molecules would be blocked by a cell membrane? Simple alcohols Ions Water Dissolved oxygen
Ions
What is the advantage to spirochetes of the corkscrew movement provided by axial filaments?
It allows the cells to move more easily through viscous human tissues and fluids, such as mucus.
A bacterial cell stains positive with the acid-fast stain. Which of the following is FALSE? It will be difficult to stain this cell with the Gram stain. It has a cell wall that contains waxy lipids. It may be a member of the genus Mycobacterium. It has a cell wall that contains endotoxin
It has a cell wall that contains endotoxin
A bacterial cell stains positive with the acid-fast stain. Which of the following is NOT true?
It has a cell wall that contains endotoxin.
Which of the following is a characteristic of a phospholipid "tail"? It is negatively charged. It is hydrophilic. It is composed of a glycerol and a fatty acid. It is hydrophobic.
It is hydrophobic.
Thiomargarita namibiensisis a notable microbe for which of the following reasons? It is the largest prokaryotic microbe ever discovered. It is a prokaryote with a primitive nucleus. It is a eukaryotic cell that is the same size as E. coli. It is a eukaryote with a prokaryotic-type flagellum.
It is the largest prokaryotic microbe ever discovered. This microbe was discovered in 1997 and, due to its extreme size for a prokaryote, made many microbiologists change the way they thought about the sizes of microbial cells.
Facilitated diffusion
Passive transport of molecules across the cell membrane that requires specific channel proteins is called
The controlled chemical reactions of cells of organisms are called_______
metabolism
The sum of all the chemical reactions within an organism is referred to as its ________.
metabolism
Which of the following statements concerning pili is FALSE?
Pili are longer than fimbriae and flagella.
Which of the following statements concerning pili is FALSE? Pili are longer than fimbriae and flagella. Pili are long, hollow tubules. Pili facilitate the transfer of DNA among bacterial cells. A bacterial cell will usually have only one or two pili. Not all bacteria have pili.
Pili are longer than fimbriae and flagella.
Which of the following terms refers to a bacterium moving towards a light source?
Positive phototaxis
Which of the following terms refers to a bacterium moving towards a light source? Negative phototaxis Negative chemotaxis Positive chemotaxis Positive phototaxis
Positive phototaxis
Which of the following would not move freely across the cytoplasmic membrane?
Positively charged hydrogen ions
Which of the following statements concerning prokaryotic flagella is FALSE?
Prokaryotic flagella are composed of tubulin.
Which of the following statements concerning prokaryotic flagella is FALSE? Treponema is an example of a bacterium that has an endoflagellum. A "run" results from counterclockwise movement of the flagellum. Prokaryotic flagella can rotate 360 degrees. Prokaryotic flagella are anchored to the cell wall by means of the basal body. Prokaryotic flagella are composed of tubulin.
Prokaryotic flagella are composed of tubulin.
Facilitated diffusion differs from diffusion primarily because facilitate diffusion involves __________
Protein Channels
. Enzyme
Protein molecule that acts as a biological catalyst, speeding up the rate of chemical reactions in living systems.
Plant cell walls are composed of ________ held together by ________.
polysaccharides, hydrogen bonds
If a eukaryotic cell suffers damage to its mitochondria, which of the following processes of life would be most immediately affected?
metabolism
Which of the following is an organelle found in both prokaryotic and eukaryotic cells? centriole peroxisome vacuole ribosome
ribosome
the following is are correct pairing
synthesis: endothermic catabolism: exothermic dehydration: anabolism electrolytes: anions
All of the following are sources of organic acids
tea lemon juice black coffee
uniport proteins
transfer only 1 type of molecule
Integral proteins are mostly involved in
transport function.
8) Formation of a biofilm may contribute to bacteria's ability to cause disease.
a
Which of the following is a property of water?
it has a high capacity for heat.
hypertonic-
water concentration is higher outside so the cell shrinks and shrivels.
__________ may have pili.
Bacteria
Nucleic Acid
Polymer of nucleotides, both DNA and RNA
As a bacterium approaches a food source, one would expect
runs to become more frequent.
Where are lipids made in the cell?
smooth endoplasmic reticulum (ER)
vacuoles
storage
Which of the following is NOT a component of bacterial cell walls?
tubulin
12) The type of organelles found only in eukaryotic cells are described as __________.
Answer: membranous
the following would normally be found as a component of a cell's nucleic acids?
*adenine deoxyribonucleotides *thymine deoxyribonucleotides *adenine ribonucleotides *cytosine ribonucleotides
An acid dissociates in water to release
...
If you know that sodium chloride molecules contain ionic bonds, which of the following electronegativity values would be appropriate for the elements sodium and chlorine?
0.9 and 3.0
The type(s) of bonds produced when atoms share electrons equally is/are? 1) a nonpolar covalent bond. 2) an ionic bond. 3) a polar covalent bond. 4) a hydrogen bond. 5) both polar covalent and ionic bonds.
1) a nonpolar covalent bond
The reverse of a dehydration synthesis reaction is a(n) _____ reaction. 1) hydrolysis. 2) exchange. 3) metabolic. 4) endothermic. 5) anabolic
1) hydrolysis
An increase in the pH of a solution by 2 whole numbers represents a change in the number of hydrogen ions by what factor?
100
Anna is conducting an experiment using pH indicator that is red at low pH, green at neutral pH, and purple at high pH. She starts with a green solution. When she adds compound X to her solution it turns purple. Then she adds Z compound to the solution and it turns green. She adds more Z and the solution remains green. The observations suggest X is ________ and Z is _________. 1) a base; a strong acid 2) a base; a buffer 3) an acid; a buffer 4) an acid; a base 5) a buffer; a base
2) a base; a buffer
Which of the following are examples of pyrimidines? 1) cytosine and guanine 2) cytosine and thymine 3) thymine and adenine 4) uracil and adenine 5) thymine and guanine
2) cytosine and guanine
Nucleic acid polymers, proteins, and complex carbohydrates are all produced by? 1) exchange reactions. 2) hydrogen bonding. 3) dehydration synthesis. 4) catabolic reactions. 5) hydrolytic reactions.
2) hydrogen bonding.
Unstable isotopes can be useful 1) as buffers. 2) in medical diagnosis. 3) in vitamins. 4) catalysts. 5) in the formation of hydrogen bonds.
2) in medical diagnosis
When the nucleus of an atom contains a constant number of protons but a variable number of neutrons, the atom is called a(n)? 1) element 2) isotope 3) valence 4) dalton
2) isotope
Pure water has a neutral pH because? 1) it is composed of polar covalent bonds. 2) it dissociates into equal numbers of hydrogen and hydroxyl ions. 3) it is a natural buffer. 4) it is composed of equal numbers of hydrogen and oxygen atoms.
2) it dissociates into equal numbers of hydrogen and hydroxyl ions.
Which of the following subatomic particles do NOT have a charge? 1) electrons 2) neutrons 3) ions 4) protons
2) neutrons
All of the following are components of an amino acid EXCEPT a(n)? 1) carboxyl group 2) pentose group 3) a-carbon 4) R group 5) amino group
2) pentose group
In discussions of atomic mass, electrons are often ignored because? 1) their mass is cancelled out by the mass of the protons in the atom. 2) their mass makes a negligible contribution to the atom's overall mass. 3) some atoms do not have many electrons. 4) they do not have an atomic mass.
2) their mass makes a negligible contribution to the atoms overall mass.
An oxygen atom has two electron shells and 6 valence electrons. How many total electrons does this atom have? 1) 4 2) 6 3) 8 4) 16
3) 8
Methane is classified as a compound because? 1) it has four bonds. 2) its bonds are covalent. 3) it contains atoms of more than one element. 4) its atoms share electrons.
3) it contains atoms of more than one element.
What is the name of the bond that forms the primary structure of a protein? 1) ionic bond 2) hydrogen bond 3) peptide bond 4) disulfide bridge
3) peptide bond
A macromolecule containing two fatty acids and a phosphate group is a? 1) steroid 2) saturated fatty acid 3) phospholipid 4) glycerol 5) wax
3) phospholipid
Which of the following is the most alkaline (basic) pH? 1) pH 2.0 2) pH 7.0 3) pH 9.0 4) pH 13.0
4) pH 13.0
An acid dissociates in water to release? 1) cations. 2) hydroxyl groups. 3) anions. 4) hydrogen ions. 5) both anions and hydrogen ions.
5) both anions and hydrogen ions
Which of the following is an example of a polysaccharide? 1) glucose. 2) deoxyribose. 3) fructose 4) sucrose 5) glycogen
5) glycogen
which parts of the atoms interact in a chemical reaction? 1) protons 2) isotopes 3) neutrons 4) electrons 5) ions
5) ions
An oxygen atom has 2 electron shells and 6 valence electrons. How many total electrons does this atom have?
8
Which pH would be alkaline?
8
1) Chloroplasts use light energy to produce ATP and carbohydrates.
A
12) Lipid A is also known as A) endotoxin. B) teichoic acid. C) tetrapeptide. D) mycolic acid. E) lipopolysaccharide.
A
20) When cells are placed in a hypertonic solution, they lose water and shrivel. This process is called A) crenation. B) endocytosis. C) passive transport. D) periplasm. E) plasmalemma.
A
24) Which of the following is classified as a membranous organelle of eukaryotic cells? A) endoplasmic reticulum B) ribosome C) cytoskeleton D) centriole E) both ribosomes and centrioles
A
3) Bacterial protein synthesis can begin before the reading of the gene is complete.
A
3) Which of the following statements concerning the characteristics of life is FALSE? A) Reproduction is defined as an increase in the size of an organism. B) Viruses have some, but not all, of the characteristics of living things. C) Organisms may not exhibit all of the characteristics of life at all times. D) Reproduction can occur asexually or sexually in living things. E) Living things store metabolic energy in the form of chemicals such as ATP.
A
13) The semiliquid matrix of the nucleus is called the __________.
Answer: nucleoplasm
30) Which of the following statements concerning the endosymbiotic theory is FALSE? A) Eukaryotes were formed from the union of small anaerobic cells by larger aerobic cells. B) Mitochondria and chloroplasts can divide independently of the cell. C) Mitochondria and chloroplasts have their own DNA and ribosomes. D) The cristae of mitochondria evolved from the cytoplasmic membrane of prokaryotes. E) The endosymbiotic theory is not universally accepted.
A
43) Some members of __________ have hami. A) archaea B) bacteria C) eukaryotes D) both archaea and bacteria E) both bacteria and eukaryotes
A
48) Which of the following have external structures containing a periplasmic space? A) Gram-negative bacteria B) Gram-positive bacteria C) both Gram-positive and Gram-negative bacteria D) archaea E) eukaryotes
A
49) Which of the following prokaryotic cells contain an outer membrane? A) Gram-negative bacteria B) Gram-positive bacteria C) both Gram-positive and Gram-negative bacteria D) archaea E) all prokaryotes
A
6) Eukaryotic ribosomes are composed of 60S and 40S subunits.
A
9) Which of the following statements concerning pili is FALSE? A) Pili are longer than fimbriae and flagella. B) Pili facilitate the transfer of DNA among bacterial cells. C) Pili are long, hollow tubules. D) Not all bacteria have pili. E) A bacterial cell will usually have only one or two pili.
A
Lipid __________ is a part of the Gram-negative cell wall that can produce fever, inflammation, and shock when it is released into the bloodstream. (Be sure to use capital letters.)
A
How are Gram-positive and Gram-negative flagella different?
A Gram-positive flagellum has only two rings in its basal body; Gram-negatives each have four.
Which of the following scenarios is an example of bacterial motility?
A bacterium moving towards a food source
endothermic
A chemical reaction that requires energy in order to proceed is called a(n) __________ reaction.
Ramona suffers from gastric ulcers, which are erosions of the mucus membrane of the stomach caused by bacteria burrowing into the protective mucus layer and allowing stomach acid to digest the stomach lining. How is an acid defined?
A molecule that dissociates into one or more hydrogen ions and one or more anions
increased; 1000 Adding 1000 times more hydrogen ions to a solution with a pH of 7.0 would create a much more acidic solution of pH 4.0.
A solution with a pH of 7.0 would become the most acidic if one __________ the hydrogen ion concentration by a factor of __________.
What is LPS?
A union of a lipid with a sugar
unsaturated and polyunsaturated
A(n) __________ fatty acid is usually liquid at room temperature and is found predominantly in plants.
Isotope
A(n) __________ is a form of an element that has more neutrons than protons.
Sodium has an atomic number of 11 and an atomic mass of 23 daltons. How many protons and neutrons does it have?
ANSWER: 12 neutrons and 11 protons
If phosphorus has an atomic number of 15, how many electron shells does a phosphorus atom have?
ANSWER: 3 (A phosphorus atom has 15 electrons orbiting its nucleus; therefore, it would require 3 electron shells to hold them, with the outer shell being filled by only 5 electrons.)
The atomic number of the element carbon is 16; this means that it has _____.
ANSWER: 6 protons in its nucleus
Which of these statements best describes a buffer?
ANSWER: A buffer is a solution that releases or absorbs H+ to keep the pH from changing. (Buffers do not always have to keep the pH at 7.0 "neutral".)
Another term for an atom is a dalton.
ANSWER: False (A dalton is another term for one atomic mass unit, which is approximately the weight of a proton or a neutron.)
An atom with a valence of +2 has two spaces it needs to fill in its outer shell.
ANSWER: False (A valence of +2 signifies that the atom has two electrons it can give up.)
Hydrogen bonds are stronger than covalent bonds but weaker than ionic bonds.
ANSWER: False (Hydrogen bonds are weaker than either covalent or ionic bonds.)
An exchange reaction is another name for a synthesis reaction.
ANSWER: False (In exchange reactions, atoms are moved from one molecule to another, making them a combination of both synthesis and decomposition reactions.)
Organic compounds are those that occur naturally in the environment.
ANSWER: False (In this case, "organic" means that the compound contains carbon and hydrogen atoms. It does not refer to where the compound originated.)
The term "metabolism" refers to all of the decomposition reactions within an organism.
ANSWER: False (Metabolism refers to all the chemical reactions that occur in an organism.)
Phospholipids placed into an aqueous environment will automatically form a bilayer.
ANSWER: False (Since phospholipids have polar and nonpolar regions, they interact with water to form either single-layer spheres or bilayers, both of which orient the hydrophobic, nonpolar regions away from the water.)
Water behaves as it does because each water molecule has two nonpolar covalent bonds.
ANSWER: False (The two polar covalent bonds in a water molecule enable it to participate in hydrogen bonding with other molecules --including water molecules-- giving water many of its unique properities.)
Sterols are found only in animal cell membranes.
ANSWER: False (While cholesterol is a type of sterol that is unique to animal cell membranes, similar types of sterols can be found in the cell membranes of fungi, plants, and even some bacteria.)
Waxes are lipids that are present in some eukaryotic cells, but not in bacteria.
ANSWER: False (While not common in bacteria, waxes are found in the cell wall of some bacteria such as species of "Mycobacterium".
The term "pH" refers to the number of hydrogen atoms in a molecule.
ANSWER: False (pH is a measurement of the concentration of hydrogen ions in a solution, not the number of hydrogen atoms in a molecule.)
Which of the following statements concerning hydrogen bonds is FALSE?
ANSWER: Hydrogen bonds are essential for life because they form strong connections between atoms. (Although hydrogen bonds are essential for life, they form relatively weak bonds.)
The stereoisomers of amino acids and sugars most commonly used by organisms are _____.
ANSWER: L amino acids and D sugars
Fats are composed of three fatty acids linked to a molecule of glycerol.
ANSWER: True (These fatty acids are long chains of carbon and hydrogen, which make the overall molecule very hydrophobic.)
Which type of molecule tends to be water soluble?
ANSWER: a molecule containing either ionic or polar covalent bonds
Which of the following nitrogenous bases is found both in the cell's genetic material and in its energy-containing molecules?
ANSWER: adenine
Which of the following nitrogenous bases are purines?
ANSWER: adenine and guanine (Guanine is a purine, but cytosine is a pyrimidine.)
Disulfide bridges are used in which level of protein structure?
ANSWER: both tertiary and quaternary
Which functional group is incorrectly matched with the type of elements present in the group?
ANSWER: carbonyl:carbon, nitrogen, and hydrogen (An amino group consists of on nitrogen and two hydrogen atoms.)
All of these are functions of carbohydrates, EXCEPT _____.
ANSWER: catalyzation of chemical reactions (Sugars such as ribose and deoxyribose are components of RNA and DNA, respectively.)
Ions that can conduct electricity in an aqueous solution are called _____.
ANSWER: electrolytes
Which of the following functional groups is NOT associated with amino acid structure?
ANSWER: ester (Amino, sulfhydryl, carboxyl, and hrdoxyl groups are all found in amino acid structures, while esters are found in the fats and waxes.)
Which of the following pairs of terms is an INCORRECT match?
ANSWER: fats:pentoses (Cellulose is an example of a polysaccharide in plants.)
Which of the following is a polysaccharide produced by animals?
ANSWER: glycogen (This is a type of starch produced by plants.)
Which of the following is a type of protein that is covalently bound to a carbohydrate?
ANSWER: glycoprotein
A solution with a pH of 7.0 would become more acidic if one _____ the hydrogen ion concentration by a factor of _____.
ANSWER: increases;1,000 (Adding 1,000 times more hydrogen ions to a solution with a pH of 7.0 would create a much more acidic solution of pH 4.0)
Two atoms that have vastly different electronegatives can form a(n) _____.
ANSWER: ionic bond (This bond results from the union of two atoms with similar electronegatives.)
All of the following are true of saturated fats, EXCEPT _____.
ANSWER: most fats in plants are saturated fats (Most fats in plants are unsaturated or polyunsaturated.)
Which of the following types of molecules is used in the transport of substances into and out of the cell?
ANSWER: proteins
Denaturation _____.
ANSWER: results in the disruption of the tertiary structure of a protein (Dehydration synthesis is the creation of a larger molecule by removing water from two smaller molecules.)
B-pleated sheets are associated with which level of protein structure?
ANSWER: secondary
Which of the following pairs of terms is an INCORRECT match?
ANSWER: synthesis:exothermic (Synthetic processes are always involve an input of energy. That is, they are endothermic.)
Carbon-13 is an isotope of carbon, which normally has an atomic mass of 12 daltons. This means _____.
ANSWER: that carbon-13 has more neutrons than carbon-12 (The number of protons in an atom of a given element does not vary. If carbon-13 had 7 protons instead of 6, it would be nitrogen, not carbon.)
All proteins have a minimum of how many levels of protein structure?
ANSWER: three (Not all proteins exhibit quaternary structure, but they do exhibit primary, secondary, and tertiary structure.)
Water is important for life for all of the following reasons EXCEPT _____.
ANSWER: water does not absorb heat energy (Water is able to absorb large amounts of heat energy without changing its own temperature.)
Any process in the cell that requires energy will typically involve the use of which of the following? RNA H2O DNA ATP
ATP
Which of the following is the cell's principal short-term, recyclable energy source? ATP glucose fats cholesterol
ATP
Why is ATP necessary for active transport?
ATP provides energy to transfer material against its concentration gradient.
What is a tumble in a flagella?
Abrupt, random changes in direction. they results from clockwise flagellar rotation where each flagellum rotates independently. Both runs and tumbles occur in response to stimuli. The presense of favorable stimuli inreasees the duration of run and decrease the number of tubles, as a result the cell tends to move toward an attractant.
Why does active transport require the expenditure of energy?
Active transport involves the transfer of material against the concentration gradient.
Why does active transport require the expenditure of energy? Active transport requires the use of transport proteins. Active transport involves the transfer of material against the concentration gradient. Active transport has to remove material at the same time it brings material into the cell. Active transport involves the transfer of material with the concentration gradient.
Active transport involves the transfer of material against the concentration gradient.
Which of the following is true? Water can freely pass through the cell membrane. Water can pass through a protein channel. Alcohol can pass freely through the cell membrane. All of the above are true. None of the above are true.
All of the above are true.
Biofilms account for about one-quarter of bacterial infections in humans
All of these are characteristics of biofilms , except
The cytoplasmic membranes of __________ contain lipids.
All prokaryotes
3) A higher concentration of solutes corresponds to a __________ (higher/lower) concentration of water in a given solution.
Answer: lower
5) The __________ body anchors the bacterial flagellum in the cell wall.
Answer: basal
11) A(n) __________ is a type of glycocalyx that is firmly attached to the cell.
Answer: capsule
9) Paired structures composed of tubulin that play a role in eukaryotic mitosis are known as __________.
Answer: centrioles
10) Fibrous structures some archaea use for attachment to surfaces are __________.
Answer: hami
1) In a(n) __________ solution, an animal cell can gain so much water that it may burst.
Answer: hypotonic
6) The reserve deposits of starch or other compounds found in many prokaryotic cells are called __________.
Answer: inclusions
You have created a small-scale ecosystem in your laboratory that exactly mimics the nitrogen cycle in nature. You accidentally release a virus into your laboratory that inserts itself into (and inactivates) the gene for nitrogenase. What would you expect to happen in your ecosystem?
Atmospheric nitrogen gas would increase and soil ammonia would decrease.
16) Which of the following statements concerning osmosis is FALSE? A) Osmosis requires a selectively permeable membrane. B) During osmosis, water crosses to the side of the membrane with a lower solute concentration. C) Cells placed in hypotonic solutions will gain water. D) Crenation results when cells are placed in a hypertonic solution. E) Osmosis stops when the system reaches equilibrium.
B
2) Peroxisomes contain enzymes used to digest nutrients that have been brought into the cell through phagocytosis.
B
25) Which of the following is NOT associated with the nucleus of a eukaryotic cell? A) chromatin B) cristae C) histones D) nucleoplasm E) nucleolus
B
29) Which of the following is paired INCORRECTLY? A) plants: cellulose cell wall B) algae: glycocalyx present C) bacteria: peptidoglycan cell wall D) fungi: cellulose, chitin, and/or glucomannan cell wall E) archaea: polysaccharide cell wall
B
32) The accumulation of glucose 6-phosphate inside a bacterial cell via phosphorylation of glucose is an example of A) facilitated diffusion. B) group translocation. C) osmosis. D) plasmolysis. E) diffusion.
B
38) Endocytosis and exocytosis are means of transport used by A) bacteria. B) eukaryotes. C) archaea. D) all prokaryotes. E) No cells use both processes.
B
39) Some __________ use group translocation as a means of transport. A) eukaryotes B) bacteria C) archaea D) prokaryotes E) eukaryotes and prokaryotes
B
4) All cell membranes contain phospholipids and a wide variety of proteins.
B
40) Hopanoids are found in __________ cytoplasmic membranes. A) eukaryotic B) bacterial C) archaeal D) prokaryotic E) no
B
46) Which of the following may have cell walls containing teichoic acids? A) Gram-negative bacteria B) Gram-positive bacteria C) archaea D) both Gram-positive and Gram-negative bacteria E) all prokaryotes
B
5) The process of facilitated diffusion requires an input of energy.
B
7) A bacterial cell moving toward light would be an example of A) tumbles. B) positive phototaxis. C) negative phototaxis. D) positive chemotaxis. E) negative chemotaxis.
B
7) Lysosomes result from the endocytosis of food particles by eukaryotic cells.
B
What are endospores?
Bacillus and Clostridium are characterized by the ability to produce unique structures called endospores, which are important for several reasons, including durability and potential pathogenicity. Endospores are not reproductive structures. They constitute a defensive strategy against hostile or unfavorable conditions. only present in bacteria
Pathogenic bacteria
Bacteria that can cause disease can be identified and classified by differences in their flagellar proteins.
Define an electrochemical gradient.
Because many of the substances that have concentration gradients across cell membranes are electrically charges chemicals, a corresponding electrical gradient, or voltage, also exists across the membrane. For example, a greater concentration of negatively charged proteins exists inside the membrane, and positively charged sodium ions are more concentrated outside the membrane.
What is the periplasmic space?
Between the cytoplasmic membrane and the outer membrane of a Gram negative bacteria. Contains the peptidolygcan and the periplasm, the name given to the gel between the membrane of these Gram negative cels. Periplasm contains water, nutrents, and substances secreted by the cell, such as digestive enzymes and proteins involved in specific transport.
The cell walls of __________ contain tetrapeptides.
Both Gram-positive and Gram-negative bacteria
Which molecule shown in the animation, the square or the circle, is moving against its concentration gradient?
Both the circle and the square
How does water enter and exit a cell?
By simple diffusion or by use of an integral transport protein
13) Bacteria of the genus Mycoplasma are distinguished from other bacterial cells by A) unique ribosomes. B) the presence of mycolic acid in their cell walls. C) the absence of a cell wall. D) cell walls composed solely of amino acids. E) the absence of a cytoplasmic membrane.
C
14) Lipid-soluble molecules would be expected to cross the cytoplasmic membrane by which of the following processes? A) osmosis B) facilitated diffusion C) diffusion D) active transport E) group translocation
C
19) Which of the following is unique to archaea? A) LPS B) peptidoglycan C) hami D) fimbriae E) pili
C
2) Which of the following is NOT a component of bacterial flagella? A) flagellin B) basal body C) tubulin D) filament E) hook
C
21) Which of the following statements concerning endocytosis and exocytosis is CORRECT? A) These processes occur in both prokaryotes and eukaryotes. B) Phagocytosis is a type of endocytosis in which liquids are brought into the cell. C) Endocytosis produces a structure called a food vesicle. D) Waste products and secretions are exported from the cell during endocytosis. E) Endocytosis is a form of passive transport, whereas exocytosis is a form of active transport.
C
27) Which of the following organelles is responsible for producing most of the ATP in a eukaryotic cell? A) lysosome B) Golgi body C) mitochondrion D) smooth endoplasmic reticulum E) nucleus
C
31) Which of the following is NOT a function of the eukaryotic cytoskeleton? A) anchors organelles B) gives shape to the cell C) packages cellular secretions D) performs endocytosis E) aids in contraction of the cell
C
33) Which of the following molecules would be expected to cross the cytoplasmic membrane rapidly and without the use of transport proteins? A) large molecules B) ions C) small hydrophobic molecules D) small hydrophilic molecules E) both ions and hydrophilic molecules
C
37) Membrane rafts are found in the cytoplasmic membranes of A) archaea. B) bacteria. C) eukaryotes. D) both archaea and bacteria. E) both archaea and eukaryotes.
C
44) __________ may have pili. A) Eukaryotes B) Archaea C) Bacteria D) Prokaryotes E) Eukaryotes and bacteria
C
47) The cell walls of __________ contain tetrapeptides. A) Gram-negative bacteria B) Gram-positive bacteria C) both Gram-positive and Gram-negative bacteria D) archaea E) all prokaryotes
C
8) Which of the following statements concerning prokaryotic flagella is FALSE? A) Prokaryotic flagella can rotate 360 degrees. B) A "run" results from counterclockwise movement of the flagellum. C) Prokaryotic flagella are composed of tubulin. D) Treponema is an example of a bacterium that has an endoflagellum. E) Prokaryotic flagella are anchored to the cell wall by means of the basal body
C
Describe how the capsule may contribute to the pathogens ability to cause disease.
Capsule is made of sugar, water. Capsule is sticky and composed of organized repeating units of organic chemicals, may prevent bacteria from being recognized by host.
Responsiveness
Cells engaging in taxis are exhibiting which of the following basic processes of life?
Carbohydrates
Class of organic molecules consisting of carbon, hydrogen, and oxygen atoms: includes monosaccharides, disaccharides, and polysaccharides.
Lipids
Class of organic molecules that tend to be soluble in nonpolar solvents such as alcohol; includes fats and oils.
What is a run in a flagella?
Counterclockwise flagellar rotation produces movements of a cell in one direction for some times.
Hypertonic
Crenation, the shriveling of cells due to loss of water occurs when cells are placed in what kind of solution?
17) Endospores survive a variety of harsh conditions in part because of the presence of A) mycolic acid. B) lipopolysaccharide. C) hopanoids. D) dipicolinic acid. E) glycoproteins.
D
18) The glycocalyx of a eukaryotic cell performs all of the following functions EXCEPT A) protection against dehydration. B) anchoring cells to each other. C) cellular recognition and communication. D) transfer of genetic material between cells. E) strengthening the cell surface.
D
23) Which of the following statements concerning centrioles is FALSE? A) The structure of centrioles is similar to that of eukaryotic flagella and cilia. B) Centrioles are believed to play a role in cellular processes such as mitosis and cytokinesis. C) Centrioles are found in a region of the cell called the centrosome. D) Centrioles are found in all organisms except prokaryotes. E) Centrioles are composed of microtubules.
D
26) Which of the following statements about the endoplasmic reticulum (ER) is CORRECT? A) The rough ER is the site of lipid synthesis. B) The smooth ER has ribosomes associated with it. C) The ER is a lipid storage organelle. D) The ER is a transport system within the cytoplasm. E) The smooth ER is a site of ATP synthesis.
D
28) Chloroplasts differ from mitochondria in that they have A) DNA. B) two lipid bilayers. C) 70S ribosomes. D) light-harvesting pigments. E) cristae.
D
36) The cytoplasmic membranes of __________ contain phospholipids and proteins. A) archaeal cells B) bacterial cells C) eukaryotic cells D) both bacterial and eukaryotic cells E) archaeal, bacterial, and eukaryotic cells
D
4) Bacterial pili can be described as A) composed of tubulin. B) solid, rigid protein structures. C) composed of peptidoglycan. D) specialized fimbriae. E) a means of locomotion.
D
22) One lipid found in eukaryotes but NOT in prokaryotes is A) hopanoid. B) lipopolysaccharide. C) phospholipid. D) fatty acid. E) steroid.
E
Which of the following would NOT be found in an inclusion? gases starch DNA lipids
DNA
What does Glycocalyces protect cells against?
Dessication, and can also play a role in the ability of pathogens to survive and cause disease. for example slime layers are often sticky and provide one means for bacteria to attach to surfaces as biofilms, which are aggregates of many bacteria living together on a surface.
Which of the following statements are false? Dissolve oxygen will travel along its concentration gradient until equilibrium is reached. Dissolve oxygen can pass freely through the cytoplasmic membrane. Dissolve oxygen requires the use of ATP to be transported into the cell. Dissolve oxygen moves from high concentrations to low concentrations.
Dissolve oxygen requires the use of ATP to be transported into the cell.
Which of the following statements concerning osmosis is FALSE?
During osmosis, water crosses to the side of the membrane with a lower solute concentration.
1) Using a microscope, you observe an amoeba moving toward a food source. This is an example of A) reproduction. B) cellular structure. C) metabolism. D) growth. E) responsiveness.
E
10) Which of the following is NOT a component of bacterial cell walls? A) peptidoglycan B) lipoteichoic acids C) mycolic acid D) tetrapeptide E) tubulin
E
11) Bacterial cell walls that are resistant to drying contain A) carbohydrates. B) amino acids. C) lipopolysaccharide. D) tubulin. E) waxes.
E
15) ATP is expended in which of the following processes? A) facilitated diffusion B) diffusion C) group translocation D) active transport E) both active transport and group translocation
E
Archaea
Hami are proteinaceous structures found in which of the following?
34) Which of the following processes requires a carrier protein? A) diffusion B) facilitated diffusion C) active transport D) endocytosis E) both facilitated diffusion and active transport
E
35) Which of the following chemical substances contributes to the unique characteristics of acid-fast bacteria? A) N-acetylglucosamine B) peptidoglycan C) lipoteichoic acid D) endotoxin E) mycolic acid
E
42) Cytoplasmic membranes of __________ are composed of phospholipids. A) bacteria B) eukaryotes C) archaea D) prokaryotes E) both bacteria and eukaryotes
E
45) __________ may have flagella. A) Archaea B) Bacteria C) Eukaryotes D) Prokaryotes E) Archaea, bacteria, and eukaryotes
E
5) Which of the following bacterial cell structures plays an important role in the creation of biofilms? A) glycocalyces B) flagella C) fimbriae D) pili E) both fimbriae and glycocalyces
E
50) The cytoplasmic membranes of __________ contain lipids. A) Gram-negative bacteria B) Gram-positive bacteria C) both Gram-positive and Gram-negative bacteria D) archaea E) all prokaryotes
E
6) Short, hairlike structures used only by eukaryotic cells for movement are called A) pili. B) flagella. C) fimbriae. D) pseudopodia. E) cilia.
E
Slime
In contrast to capsule, slime is a loose, water-soluble glycocalyx. slime
___________is the process by which large molecules or extracellular fluids are brought into a eukaryotic cell through manipulation of the cytoplasmic membrane.
Endocytosis
Understand the difference between pinocytosis and phagocytosis.
Eukaryotic cells only. Endocytosis: occurs when the membrane distends to form pseudopods that surround an object, bringing it into the cell. Phagocytosis is a solid object, and pinocytosis is a liquid is brought into the cell
Denaturation of a protein is always permanent.
False
Hydrogen bonds are stronger then covalent bonds.
False
The electron shells of atoms hold eight electrons each.
False
The smallest chemical units of matter are elements.
False
T/F Membrane rafts are used by eukaryotic cells to make their membranes more fluid and flexible.
False By definition, membrane rafts are areas of the membrane that contain lipids and proteins that do not flow independently like much of the rest of the membrane's components. These rafts are used for various important cell functions, such as cell signaling and protein sorting.
T/F The capsule found in some bacterial cells is a loose, water-soluble structure.
False Capsules are well-organized, fairly rigid structures; slime layers are loose and water soluble.
9) Chromatin is composed of DNA and special packaging proteins called hopanoids.
a
T/F Since all cells use their ribosomes to produce proteins, the ribosomes of eukaryotic cells are identical to those of prokaryotic cells.
False Eukaryotic ribosomes are larger than those of prokaryotes.
T/F Phagocytosis is a process that allows a cell to release wastes.
False Exocytosis is a process to export substances from the cell.
T/F Magnetobacteria contain the mineral magnetite in large ribosomes spread throughout the bacterial cytoplasm.
False Inclusions are deposits placed throughout the cytosol of bacteria. Ribosomes, on the other hand, are used for protein synthesis.
T/F When Gram-positive bacteria die, a large amount of lipid A can be released into the immediate environment.
False Lipid A is found only in Gram-negative bacteria, not Gram-positive bacteria.
What structural part of a bacterial flagellum is composed of flagellin?
Filament
What is the function of flagella in prokaryotes? How are they arranged?
Flagella are the most notable structures responsible for bacterial movement. assist the cell in movement, bacterial flagella are long structures that extend beyond the surface of a cell and its glycocalyx and propel the cell through its environment.
Which of the following statements about bacterial flagella is true?
Flagella can rotate 360 degrees.
Which of the following statements about bacterial flagella is true? Flagella work by undulating. Bacteria can only rotate flagella counterclockwise. Flagella can rotate 360 degrees. Bacteria can only rotate flagella clockwise
Flagella can rotate 360 degrees.
Which of the following is correct for a peritrichous bacterium? There is a flagellum at both ends of the cell. Flagella cover the cell surface. The flagella bundle together when they rotate clockwise. Peritrichous cells have only a single flagellum.
Flagella cover the cell surface.
peritrichous
Flagella that cover the surface of the cell are termed peritrichous
Which of the following is a FALSE statement concerning flagella? "Runs" and "tumbles" are characteristic of prokaryotic cell movement. Eukaryotic flagella have a "9 + 2" microtubule arrangement. Flagellin is a molecule found only in eukaryotic flagella. Prokaryotic flagella are composed of a filament, basal body, and hook.
Flagellin is a molecule found only in eukaryotic flagella.
cytoskeleton
Function for shape in prokaryotes; support, Cytoplasmic streaming. Function for endocytosis in eukaryotes.
Nucleic acid (DNA)
Function: Genetic information
Carbohydrate (polysaccharide; starch)
Function: energy storage
Lipid (Phospholipid)
Function: membrane bilayer
Lipid (steroid/sterol)
Function: membrane fluidity, hormone and bile salt precursor
What is a glycocalyx?
Gelatinous, sticky substance surrounding the outside of the cell. Composed of polysaccharides, polypeptides or both.
What are the special external features in bacteri that enable them to respond to other cells and their environment?
Glycocalyses, flagella, fimbriae, and pili
Which of the following is part of the endomembrane system?
Golgi apparatus
Secretory vesicles are associated with which of the following? mitochondria Golgi body nucleus centrosome
Golgi body
A periplasmic space is found in which of the following? Gram-negative cells only Gram-positive cells only both Gram-positive and Gram-negative cells neither Gram-positive nor Gram-negative cells
Gram negative cells only
Gram+
Gram+ appear purple, multiples layers of peptidoglycan, peptido is referring to protein and sugars. Relatively thick layer of peptidoglycan, also contains unique chemicals called teichoic acids.
Gram-
Gram- stain red or pink, single, thin layer of peptidoglycan, but outside this layer is another, outer bilayer membrane composed of two different layers or leaflets. Inner leaflet or the outer membrane is composed of phospholipids and proteins, but the outer leaflet is made of lipopolysaccharides, (LPS) The outer membrane is protective, allowing Gram negative bacteria such as E. coli to better survive in harsh environments.
Which of the following have external structures containing a periplasmic space?
Gram-negative bacteria
Which of the following prokaryotic cells contains an outer membrane?
Gram-negative bacteria
Porins are present in ______________bacteria because, in these organisms, molecules entering the cell must pass through an extra layer of ___________.
Gram-negative; membrane
Which of the following may have cell walls containing teichoic acids?
Gram-positive bacteria
Which of the following may have cell walls containing teichoic acids? Gram-negative bacteria Archaea Gram-positive bacteria Both Gram-positive and Gram-negative bacteria All prokaryotes
Gram-positive bacteria
What are the 4 mojor processes of living things?
Growth, respnosiveness, Reproduction, metabolism
________ are fibrous structures some archaea use for attachment to surfaces.
Hami
Which of the following is true regarding the basal body of bacterial flagella? It permits the flagella to rotate 180 degrees. The basal body is comprised mostly of flagellin. It may have two or four rings if the bacterium is Gram-positive or Gram-negative, respectively. The filament is directly inserted into the basal body.
It may have two or four rings if the bacterium is Gram-positive or Gram-negative, respectively.
What is a hallmark of passive transport across cell membranes?
It occurs along an electrochemical gradient, and may involve the use of transport proteins.
What is the function of permeases in specific facilitated diffusion?
It permits only one type of molecule to pass through the cytoplasmic membrane.
Which of the following statements regarding active transport is false?
It powers the diffusion of water across the cell membrane.
Which of the following statements regarding active transport is false? It powers the diffusion of water across the cell membrane. It requires ATP. It requires the use of a transport protein.
It powers the diffusion of water across the cell membrane.
A bacterial cell possesses a glycocalyx. Which of the following is NOT true?
It will be engulfed more quickly by defensive cells of the host.
A bacterial cell possesses a glycocalyx. Which of the following is NOT true? It will be less likely to dry out. It will be able to attach to surfaces. It will be more pathogenic. It will be engulfed more quickly by defensive cells of the host
It will be engulfed more quickly by defensive cells of the host.
Growth
Living things can grow; increase in size
Which of the following types of bacterial cells would have flagella located at only one end of the cell?
Lophotrichous and monotrichous
Which of the following types of bacterial cells would have flagella located at only one end of the cell? Monotrichous and amphitrichous Amphitrichous Lophotrichous and monotrichous Lophotrichous Peritrichous Monotrichous
Lophotrichous and monotrichous
polymers
Macromolecules such as proteins or carbohydrates are referred to generically as __________, because they are long chains of simple molecules.
Some microorganisms, such as Helicobacter pylori, can alter the pH of their environment. How is this characteristic used in the microbiology laboratory?
Microbiologic media can be formulated to change color in response to pH changes -Change in color of pH indicators are often used to distinguish between various species of bacteria.
Structural Isomers
Molecules with the same molecular formula but different molecular structures.
Which of the following types of bacterial cells would have only a single flagellum?
Monotrichous
Which of the following types of bacterial cells would have only a single flagellum? Lophotrichous Monotrichous Lophotrichous and monotrichous Peritrichous Amphitrichous
Monotrichous
Positive chemotaxis
Movement of a bacterium toward the chemical substance is called
The bacterial genus_________ is named for the presence of mycolic acid in its cell walls.
Mycobacterium
Is there an advantage to having mycolic acids or waxy lipids in the cell wall?
Mycolic acid assists the cells in surviving desiccation (drying out) , makes them difficult to stain with regular water-based dyes. Use acid-fast stain to stain these cells. very hardy bacteria. common organism is Mycobacterium tuberculosisI causative agent in TB.
Which of the following molecules is shared by both Gram-positive and Gram-negative organisms?
N-acetylmuramic acid
hydrophobic
Nonpolar molecules, such as the fatty acid "tails" of a phospholipid, have a relationship to water that is described as __________.
Reproduction
Normal ability to reproduce themselves and increase in number. reproduction is an increase in number, growth is increase in size. asexual and sexual.
sequence
Nucleic acids are considered informational molecules because information for all molecules of a cell is contained in the __________ of nucleotides.
Where is the genetic information of the cell stored
Nucleus
Amino Acid
Organic molecule having an amino group and an acid group, that covalently bonds to produce protein molecules.
Responsiveness
Respond to their environment. ability to change themselves in reaction to changing conditions.
The basal body is comprised of which structural component(s) of flagella?
Rod and Rings
phosphorus, sodium, and sulfur
Saturn's moon Enceladus contains water, carbon, hydrogen, nitrogen, and oxygen. What other elements are needed to support microbial life?
Schleiden and Schwann
Scientists who proposed that all living things are composed of cells were
How is simple diffusion different from other types of passive transport?
Simple diffusion does not require a permease.
statements concerning nucleic acids are true
Some viruses have DNA as their genomes. Cytosine is found in all nucleic acid molecules. Not all DNA is double stranded. Nucleic acid strands are held together by hydrogen bonds between complementary bases
osmosis-
Special name given to the diffusion of water across a semipermeable membrane-that is, across a membrane that is permeable to water molecules but not to most solutes that are present, such as proteins, amino acids, salts, or glucose. Water
endoflagella
Spiral shaped bacteria called Spirochetes: have flagella at both ends that spiral tightly around the cell instead of protruding into the surrounding medium, these flagella are called endoflagella, and they form an axial filament that wraps around the cell between its cytoplasmic membrane and an outer membrane. Treponema pallidum, agent of syphilis, and Borrelia burgdorferi, cause of lyme disease, are notable spirochetes. Scientists think that the corkscrew motility of these pathogens allows them to invade human tissues.
________ are molecules such as amino acids that have identical atoms and functional groups, but are mirror images of each other.
Stereoisomers
Which type of active transport protein moves two molecules into the cell at the same time?
Symport
Metabolism
The ability of organisms to take in nutrients from outside themselves and use the nutrients in a series of controlled chemical reactions to provide energy and structures needed to grow, reproduce and be responsive. Store metabolic energy in ATP.
How do axial filaments differ from regular bacterial flagella?
The axial filament is located between the cell membrane and the outer membrane.
How does a bacterium "know" when a light source is present?
The bacterium contains receptors that are sensitive to the light.
What do Streptococcus pheumoniae and Kliebsella pheumoniae have in common?
The capsules enable these prokayrotes to avoid destruction by defensive cells in the respiratory tract and to cause pneumonia. unencapsulated strains of these same bacterial species do not cause disease because the body's defensive cells destroy them
A bacterial cell is placed in distilled water. Which of the following will happen?
The cell will gain water.
What will happen to a cell that is placed in a solution containing a high concentration of sugar, a molecule that cannot pass across the cell membrane?
The cell will lose its interior water, causing it to shrivel up and possibly die.
If a cell is placed in a high salt environment, what is likely to happen?
The cell will lose its interior water, shrivel up, and die.
Why is no energy required in passive transport?
The concentration gradient drives the movement.
Is composed primarily of phospholipids and proteins
The cytoplasmic membrane
The number of rings in the basal body
The difference between flagella and gram-positive bacteria and those on gram-negative bacteria has to do with
Chloroplasts
The endosymbiotic Theory is one possible explanation for the origin of which of the following organelles?
How do eukaryotic flagella differ from prokaryotic flagella? There are no differences between eukaryotic and prokaryotic flagella. A eukaryotic flagellum can rotate in only one direction. Prokaryotic flagella do not contain a basal body. The filament of a eukaryotic flagellum is covered by a membrane.
The filament of a eukaryotic flagellum is covered by a membrane.
Enhances destruction of the microbe by immune cells
The glycocalyx of microbial cells has all of the following functions except
statements concerning nucleic acids is FALSE?
The nucleic acid polymer is composed of peptide bonds.
you know that a particular chemical reaction involves the production of smaller molecules from the breakdown of larger molecules, which of the following statements would you expect to be true?
The reaction releases energy
Why are receptors on the cell surface necessary for bacterial movement?
The receptors sense the stimulus and send signals to the flagella.
monosaccharide
The simplest type of carbohydrate is a(n) __________.
Diagram a phospholipid bilayer membrane.
The structure of a cytoplasmic membrane is referred to as a phospholipid bilayer. Bipolar, meaning the two ends of the molecule are different. The phosphate containing heads of each phospholipid molecule are hydrophilic, so they are attracted to water. The hydrocarbon tails of each phospholipid molecule are hydrophobic and huddle together with other tails in the interior of the membrane, away from water. A phospholipid bilayer is naturally impermeable to most substances.
Which of the following statements about proteins is FALSE?
Their primary function is energy storage.
Why are ATPases used in active transport?
They allow the systems to use the energy from ATP to power the transfer of material against the concentration gradient.
Which of the following statements about proteins are correct
They are formed by dehydration synthesis reactions. They are composed of amino acids. They have multiple levels of structural organization. They can be hydrophobic, hydrophilic, or both.
What is the common trait of ALL lipids?
They have atoms linked by nonpolar covalent bonds
What makes phospholipid membranes good at keeping some molecules out, and allowing others to freely pass?
They have both hydrophilic and hydrophobic regions.
Why are ATPases associated with active transport proteins?
They provide transport proteins with the energy needed to pump molecules against their concentration gradients.
What is a characteristic that all forms of active transport share?
They use transport proteins to facilitate the transport of material.
What is a characteristic that all forms of active transport share? They use transport proteins to facilitate the transport of material. They bring molecules into and out of the cell at the same time. They bring material into and out of the cell wall. They bring material in with the concentration gradient
They use transport proteins to facilitate the transport of material.
It is the largest prokaryotic microbe ever discovered
Thiomargarita namibiensis is a notable microbe for which of the following reasons?
Carbohydrates are composed of carbon, hydrogen, and oxygen.
True
Monosaccharides are usually found in cyclic forms.
True
One of the products of dehydration synthesis reactions is water.
True
Salts are produced from exchange reactions in which acids and bases neutralize each other.
True
T/F Several types of cell can have a glycocalyx.
True
The side groups of amino acids can interact with each other and with other molecules
True
True of False? Bacterial protein synthesis can begin before the reading of the gene is complete.
True
The reserve deposits of starch or other compounds found in many prokaryotic cells are called ________.
inclusions
T/F In the presence of a favorable stimulus, a bacterium will increase the number of runs and decrease the number of tumbles it performs.
True A tumble is a disorganized type of movement made in the presence of unfavorable stimuli; a bacterium would decrease its tumbles and increase its runs in the presence of favorable stimuli.
T/F The ability of the archaea to live in extreme environments is due in part to their cytoplasmic membrane composition.
True Archaeal cytoplasmic membrane lipids contain ether linkages instead of the ester linkages common in bacterial cytoplasmic membrane lipids, making them stronger in more extreme environments.
T/F All types of cells can have a glycocalyx.
True Glycocalyces can be found in bacterial, archaeal, and eukaryotic cells.
T/F Eukaryotic flagella, unlike the flagella of prokaryotes, are enclosed within the cytoplasmic membrane.
True In eukaryotic cells, the flagellum is technically within the cell and is covered by an extension of the cytoplasmic membrane.
T/F Endospores are a concern to healthcare workers because they are resistant to treatments that inhibit other microbes.
True Many endospore-forming bacteria produce toxins.
T/F Sterols, found in eukaryotic cytoplasmic membranes, make these membranes stronger at high temperatures and more fluid at low temperatures.
True Sterols are characteristic components of eukaryotic membranes and are used primarily to keep the membranes fluid at lower temperatures.
ionic or a polar covalent bond
Two atoms that have significantly different electronegativities can form a(n) __________.
Polypeptide/Protein
Two or more amino acids joined together by covalent bonding.
Which transport protein employs transporters that move molecules only in one direction?
Uniport and Symport
How is osmosis different from simple diffusion?
Water movement is driven by the concentration of solutes rather than its own concentration.
Human cells lack a wall in there for the anti-biotic would damage the bacterial cell without damaging our own cells
We can safely use the cell wall of a bacteria as a target for antibiotics because
Which of the following statements regarding bacterial flagella is true? When the flagellum or flagella rotate counterclockwise, the bacterium runs. Bacteria flagella are located only at the ends of the cell. Bacteria with peritrichous flagella arrangement cannot make runs. When the flagellum or flagella rotate clockwise, the bacterium runs.
When the flagellum or flagella rotate counterclockwise, the bacterium runs.
ionic
When two atoms with greatly different electronegativities come together, one atom may lose an electron while the other atom gains an electron to form a(n) __________ bond.
Peptidoglycan
Which of the following components of the bacterial cell wall is found in varying amounts in both gram-positive and gram-negative cells?
Pili
Which of the following has not yet been discovered in the archaea?
Amino acids link the NAM and NAG molecules together
Which of the following is NOT component of peptidoglycan?
Flagellin is a molecule found only in eukaryotic flagella
Which of the following is a FALSE statement concerning flagella?
Movement toward chemicals or light
Which of the following is not a primary function of the fimbriae?
Attachment of the mitochondria and chloroplasts to the cytoplasmic membrane of the cell
Which of the following is not evidence that supports the endosymbiotic theory?
Electrically charged molecules
Which of the following kinds of molecules would not be expected to cross the cytoplasmic membrane by diffusion alone?
Rough endoplasmic reticulum
Which of the following organelles is involved in producing and transporting proteins throughout the cell?
Peroxisome
Which of the following organelles is involved in the degradation of toxic molecules?
Ribosomes
Which of the following organelles is present in both prokaryotic and eukaryotic cells?
fats: pentoses Cellulose is an example of a polysaccharide in plants.
Which of the following pairs of terms is an INCORRECT match?
synthesis: exothermic Anabolism occurs when chemical bonds are formed between molecules, creating macromolecules.
Which of the following pairs of terms is an INCORRECT match?
Hook
Which of the following structures is NOT present in eukaryotic flagella?
DNA
Which of the following would NOT be found in an inclusion?
Endospores are a component of all bacteria, but not archaea
Which of these does not correctly describe endospores?
Are all of the major processes observed in archae, prokaryotes, eukaryotes and viruses?
Yes they all are present in archea, prokaryotes and eukaryotes as long as the cell is stable. viruses reproduce their entire cell and do not go through the major processes of life. Growth does not occur in viruses, for reproduction the host cell replicated the virus. there is a responsiveness reaction to host cells seen in some viruses. Viruses use hot cell's metabolism. Viruses lack cytoplasmic membrane or cellular structure.
Reactants
__________ are the atoms or molecules that are present at the beginning of a reaction.
Electronegativity
__________ describes the attraction of an atom's nucleus for its own electrons and those of other atoms.
Denaturation
__________ is any process by which the three-dimensional structure of a protein is disrupted.
10) The Golgi body prepares cellular products for export.
a
8) Lipid __________ is a part of the Gram-negative cell wall that can produce fever, inflammation, and shock when it is released into the bloodstream. (Be sure to use capital letters.)
a (thats wat the thing sais dont blame meeh)
Which of the following scenarios would be considered bacterial motility? a photosynthetic bacterium moving toward a light source a bacterium being washed off the skin during hand washing a bacterium swimming away from a high concentration of a toxic compound all of the above none of the above
a bacterium swimming away from a high concentration of a toxic compound
Sucrose is an example of which of the following?
a disaccharide
Glucose is an example of what type of carbohydrate?
a hexose monomer
Organisms use carbohydrates in all of the following ways
a long-term energy source. as a building block of DNA and RNA molecules. as a short-term energy source. as a component of cell walls
All of the following are associated with ATP molecules EXCEPT
a long-term energy supply
The type(s) of bond produced when atoms share electrons equally is(are)
a nonpolar covalent bond.
All of the following are components of an amino acid EXCEPT
a pentose group.
All of the following are associated with ATP molecules
a recyclable energy supply. formation of coenzymes. high-energy bonds. three phosphate groups
An endothermic reaction __________.
absorbs energy
Prokaryotes that grow best under acidic conditions are called __________.
acidophiles
Organisms that have the ability to tolerate low pH ranges, such as the Helicobacter pylori that are causing Ramona's ulcers, are referred to as __________.
acidophiles H. pylori are able to survive very acidic conditions of 1.5 while acid is actively secreted into the stomach. This tolerance of pH range is referred to as acidophilic, which means acid loving.
Which form of transport might require an integral protein channel?
active and passive
group translocation-
active process that occurs only in some bacteria. the substance being actively transported across the membrane is chemically changed during transport. The membrane is impermeable to the altered substance, trapping it inside the cell. Group Translocation is very efficient at bringing substances into a cell. glucose, mannose, fructose. Eukaryotes do not perform group translocation.
active transport
active transport utilizes transmembrane permease proteins; however, the functioning of active transport proteins requires the cell to expend ATP to transport molecules across the membrane. Some such proteins are referred to as gated channels or ports because they are controlled. Na+, K+, Ca^2+, H+, Cl-
mitochondria
aerobic ATP production, powerhouse of cell. two membranes, each composed of a phospholipid bilayer. inner layer forms cristae which produces more of the ATP.
What is the role of the basal body? to rotate the flagella 360 degrees to cause the bacteria to make a run to cause the bacterium to tumble all of the above none of the above
all of the above
Which of the following are forms of passive transport? diffusion specific facilitated diffusion nonspecific facilitated diffusion osmosis all of the above none of the above
all of the above
Which of the following is a property of axial filaments? They are located between the cell membranes and outer membranes. They do not protrude from the cell wall. They cause the bacterium to corkscrew through the medium. all of the above none of the above
all of the above
A phospholipid bilayer that surrounds the cytoplasm of a prokaryotic cell is known as the _____________. cytoplasmic membrane. cell membrane. plasma membrane. all of the above. none of the above.
all of the above.
Nonspecific permeases
allow a variety of molecules to cross the cytoplasmic membrane.
The "spine" of the DNA molecule is composed of
alternating phosphates and pentoses.
All of the following are components of an amino acid
an amino group. a carboxyl group. an α-carbon. an R group.
Two atoms with vastly different electronegativities can form which of the following?
an ionic bond
The rings
anchor the flagellum to the cell membrane.
The rings
anchor the flagellum to the cell wall.
Which of the following eukaryotic cell wall types is INCORRECTLY matched? fungi: chitin algae: agar animal cell: silica plants: cellulose
animal cell: silica The fungal cell walls contain chitin, which is the same polymer used by insects for the exoskeleton.
Sodium and potassium ions need to be pumped simultaneously against their concentration gradients. Which one of the transport proteins would be most effective at this?
antiport
Which type of transport is responsible for maintaining the voltage potential across the cell membrane?
antiport
Which type of transport protein brings material into and out of the cell? uniport antiport symport #2 and #3 all of the above
antiport and symport
Which type of transport protein brings material into and out of the cell?
antiports
centrosomes
appears to play a role in mitosis, cytokinesis, and flagella and cilia formation in animals cells. not present in prokaryotes
All of the following statements are true of archaeal flagella EXCEPT: arachaeal flagella rotate from the flow of hydrogen ions across a membrane the proteins of the flagella differ from bacterial flagellin arachaeal flagella are 10-14 nm in diameter arachaeal flagella grow by adding subunits at the base—not the tip—of the flagella
arachaeal flagella rotate from the flow of hydrogen ions across a membrane The protiens of aracheal flagella are conserved among archaea.
Some members of the __________ have hami.
archaea
Which of the following groups of microorganisms contains members that are prokaryotes with a cell wall composed of protein or polysaccharides? bacteria archaea algae protozoa
archaea Bacteria are prokaryotes with cell walls made of peptidoglycan.
Hami are proteinaceous structures found in which of the following? eukaryotes archaea and bacteria bacteria archaea
archaea Hami are sticky, bristlelike projections found on some archaeal cells that allow them to attach to various surfaces.
__________ may have flagella.
archaea, bacteria, eukaryotes
The hami of some archaea are used for which of the following processes?
attachment
The hami of some archaea are used for which of the following processes? attachment defense reproduction locomotion
attachment
41) The cell walls of __________ contain peptidoglycan. A) archaea B) bacteria C) eukaryotes D) prokaryotes E) bacteria and eukaryotes
b
Some __________ use group translocation as a means of transport.
bacteria
The cell walls of __________ contain peptidoglycan.
bacteria
__________ may have pili.
bacteria
All of the following are microbes paired with a cellular feature present in some--which pair is incorrect because that feature is never present in that microbe? bacteria; fimbriae archaea; hami bacteria; cilia eukaryotes; flagella
bacteria; cilia Structural characteristics of prokaryotes include flagella, fimbriae, pili and hami.
Hopanoids are found in __________ cytoplasmic membranes.
bacterial
All of the following are differences between bacterial flagella and eurkaryotic flagella EXCEPT that __________. eukaryotic flagella are within the cytoplasmic membrane, whereas prokaryotic flagella are not eukaryotic flagella are shafts composed of globular protein tubulin arranged to form microtubules, whereas prokaryotic flagella are composed of flagellin bacterial flagella move in a wave motionwhereas eukaryotic flagella rotate 3600 the filaments of the eukaryotic flagella are anchored in the cytoplasm by a basal body, wherease the prokaryotic flagella is anchored to the plasma membrane and cell wall by a basal body.
bacterial flagella move in a wave motionwhereas eukaryotic flagella rotate 3600
The ________ anchors the bacterial flagellum in the cell wall.
basal body
A(n) ________ is a molecule that binds with hydrogen ions when it is dissolved in water.
base
Hydrogen bonds are found in all of the following
between the R groups of amino acids in proteins. in the DNA double helix between nucleotides. between water molecules. in α-helices.
Amoxicillin is an antibiotic that inhibits the formation of peptide cross-links. Amoxicillin, therefore, would most likely inhibit the growth of __________.
both Gram-positive and Gram-negative organisms
ATP is expended in which of the following processes?
both active transport and group translocation
Cytoplasmic membranes of __________ are composed of phospholipids.
both bacteria and eukaryotes
Which of the following bacterial cell structures plays an important role in the creation of biofilms?
both fimbriae and glycocalyces
Which of the following bacterial cell structures plays an important role in the creation of biofilms? fimbriae glycocalyces flagella pili both fimbriae and glycocalyces
both fimbriae and glycocalyces
Which of the following types of chemical bonds do carbon atoms generally NOT form?
both ionic and hydrogen bonds
lysosomes
breakdown of nutrients, self-destruction of damaged or aged cells. found in animal cells. contain catabolic enzymes that damage the cell if they are released from their packaging into the cytosol
A(n) (indicator/base/buffer) is a substance that maintains the pH even when the amounts of acid and/or base are changing.
buffer
A(n) ________ is a substance that maintains the pH even when the amounts of acid and/or base are changing.
buffer
Proteins contain both acidic and basic R groups, and can therefore function as
buffers.
Hydrophobic molecules move across a membrane
by passive transport directly across the membrane.
Pathogenic bacteria
can be identified and classified by differences in their flagellar proteins.
Pathogenic bacteria _______________________. do not have flagella. are unique because they have a membrane covering the filament. have a unique basal body structure. can be identified and classified by differences in their flagellar proteins.
can be identified and classified by differences in their flagellar proteins.
Which of the following is NOT a characteristic of a eukaryotic cell? more complex than prokaryotes has membrane-bound organelles has a nuclear envelope can make proteins simultaneously to reading the genetic code
can make proteins simultaneously to reading the genetic code
A(n) ________ is a type of glycocalyx that is firmly attached to the cell.
capsule
Spirochetes _______________________. are spiral-shaped bacteria. cause diseases like Lyme disease. have a spiral-shaped external flagellum. cause diseases like Lyme disease AND are spiral-shaped bacteria. have a spiral-shaped external flagellum AND cause diseases like Lyme disease.
cause diseases like Lyme disease AND are spiral-shaped bacteria.
The presence of a(n) ________ enables bacterial and plant cells to resist the effects of hypotonic solutions.
cell wall
Which of the following polysaccharides constitutes the cell walls of plants and green algae and is the most abundant polysaccharide on Earth? amylopectin glycogen cellulose amylose
cellulose
Which of the following is NOT a membranous organelle within a eukaryotic cell? endoplasmic reticulum nucleus centrosome chloroplast
centrosome
A special region of eukaryotic cytoplasm called the_______ plays a role in mitosis and cytokinesis
centrosome This region of the cytoplasm contains the centrioles if they are present in that particular cell.
what is a permease?
channel proteins that are specific in carrying only certain substrates. A permease has a binding site that is selective for on substance. Found in Facilitated Diffusion.
Which of the following eukaryotic organelles is associated primarily with photosynthetic cells and organisms? endoplasmic reticulum Golgi body mitochondrion chloroplast
chloroplast
Light-harvesting organelles found in all photosynthetic eukaryotes are called_______ .
chloroplasts
The endosymbiotic theory is one possible explanation for the origin of which of the following organelles? peroxisomes chloroplasts Golgi bodies centrioles
chloroplasts Both chloroplasts and mitochondria are organelles thought to have arisen through the process of endosymbiosis.
KH2PO4 acts as a buffer by __________.
combining with hydrogen ions
isotonic
concentration of solutes to water is equal so the cell stays the same.
nucleus
control center of the cell
When cells are placed in a hypertonic solution, they lose water and shrivel. This process is called
crenation.
facilitated diffusion-
cytoplasmic membranes contain integral proteins. Some of these proteins act as channels or carriers to allow certain molecules to diffuse down their concentration gradients into or out of the cell . the proteins facilitate the process nu providing a pathway for diffusion. The cell expends no energy in facilitated diffusion; electrochemical gradients provide all of the energy necessary. transported substances are glucose, fructose, urea, and some vitamins
Which of the following are examples of pyrimidines?
cytosine and thymine
The structural framework in the cell is the
cytoskeleton
The_________ is an internal network of fibers that gives most cells their shape.
cytoskeleton
Fats, proteins, and complex carbohydrates are all produced by
dehydration synthesis
Catabolism includes all of the following types of reactions
dehydration synthesis reactions
Which of the following processes does not involve ammonia?
denitrification
Which of the following processes does not result in a product that can be directly utilized by plants?
denitrification
Define inclusion and give two examples.
deposits found within bacteria cytosol, may include fats, starch, stored deposits. such chemicals may be taken in and stored in the cytosol when nutrients are in abundance and then utilized when nutrients are scarce. polyhydroxybutyrate (PHB)- slight chemical modification of PHB produces a plastic that can be used for packaging and other applications magnetobacteria- small crystals of magnetite. infoldings of the cytoplasmic membrane surround the magnetite to form membrane bound sacs.
What is the fluid mosaic model?
describes our most current understanding of membrane structure. The term mosaic indicates that the membrane proteins are arranged in a way that resembles the tiles in a mosaic, and fluid indicates that the proteins and lipids are free to flow laterally within a membrane.
What are serovars?
differences in the proteins associated with bacterial flagella vary enough to allow classification of species into groups (strains) called serovars.
Lipid-soluble molecules would be expected to cross the cytoplasmic membrane by which of the following processes?
diffusion
Endospores survive a variety of harsh conditions in part because of the presence of
dipicolinic acid.
Which of the following molecules can freely pass through the cytoplasmic membrane? simple alcohols hydrophobic molecules dissolved oxygen ions dissolved oxygen AND simple alcohols none of the above
dissolved oxygen AND simple alcohols
passive-
does not require energy. the electrochemical gradient provides the source of energy; the cell does not expend its energy reserve. Passive process are diffusion, facilitated diffusion, and osmosis.
nuclear envelopes
double membrane surrounding the nucleus
Compounds that readily dissociate in water are
either polar or ionic
All of the following are associated with ionic bonds EXCEPT
electrolytes. cations. salts. anions.
Which parts of the atoms interact in a chemical reaction?
electrons
Axial filaments are composed of
endoflagella
Axial filaments are composed of _______________.
endoflagella
Spirochetes have a special kind of flagella called_____ .
endoflagella
The structures that permit bacteria such as Treponema pallidum to "corkscrew" through a medium are called __________.
endoflagella
What are absent in all prokaryotes?
membranous organelles
Which of the following membrane-bound organelles is INCORRECTLY paired with its primary function? mitochondrion: aerobic ATP production lysosome: breakdown of aged cell components endoplasmic reticulum: exocytosis and secretion nucleus: contains DNA and nucleoli
endoplasmic reticulum: exocytosis and secretion The endoplasmic reticulum is involved in transport, lipid synthesis, and protein synthesis.
Bacteria in the genera Bacillus and Clostridium can create______ in order to survive harsh conditions.
endospores
A synthesis reaction is also considered which of the following types of reactions?
endothermic
chemical reaction that traps energy within newly formed chemical bonds is a(n) ________ reaction.
endothermic
Lipid A is also known as
endotoxin.
The eukaryotic cytoskeleton is composed of all of the following EXCEPT __________. enzymes tubulin intermediate filaments microfilament
enzymes Enzymes are structural proteins, a type of protein that acts as a catalyst.
how are flagella in eukaryotic cells different than prokaryotic cells?
eukaryotes undulate rhythmically , positive and negative phototaxis and chemotaxis are seen in eukaryotic cells, but such cells do not move in runs and tumbles.
golgi bodies
exocytosis, secretion, shipping department of the cell. receives, process, and packages large molecules fo export. packages secretions in sacs called secretory vesicles.
Passive transport of molecules across the cell membrane that requires specific channel proteins is called __________.
facilitated diffusion
Which of the following molecules could move easily through a lipid bilayer? proteins phosphate functional groups fatty acids sugars
fatty acids Lipids are able to move easily through the lipid bilayer.
What structural part of a bacterial flagellum is composed of flagellin?
filament
What are the 3 parts of flagella?
filament-long hollow shaft that extends out into the cell's environment. Composed of many identical globular molecules of a protein called flagellin, bacterial flagella react to external wetness, inhibiting their own growth in dry habitats. hook-cmposed of a different protein and basal body- anchors the filament and hook to the cell wall and cytoplasmic membrane by means of a rod and a series of either two or four rings or integral proteins. Together h hook, rod and rings allow the fillament to rotate 350 degrees.
The filament and basal body are associated with which of the following external structures found in some bacterial cells?
flagella
Polar
flagella only at the ends, some cells have tufts of polar flagella
Flagellin _____________________. is the major protein that comprises the hook. is found only in Gram-negative bacteria. forms helical chains that make up the filament. allows the flagellum to rotate 360 degrees.
forms helical chains that make up the filament.
ribosomes
function for protein synthesis, present in prokaryotes and eukaryotes
nuclear pore
function the control the import and export of substances through the envelope.
Nucleotide (Guanine)
functional groups: 1 Phosphate, 1 Hydroxyl, 1 Keto, 1 Amino
Amino acid (Cysteine)
functional groups: 1 amino, 1 carboxyl, 1 sulfhydryl
Fatty acid, saturated (Margaric acid)
functional groups: 1 carboxyl
Simple Sugar (Deoxyribose)
functional groups: 3 hydroxyls
Simple Sugar = Monosaccharide (Glucose)
functional groups: 5 Hydroxyls
The presence of a glycocalyx would NOT be expected in which of the following? animal cells bacteria protozoan cells fungi
fungi
glycocalyx-
gelatinous sticky substance that surrounds the outside of the cell. literally translated as sweet cup. composed of polysaccharides, polypeptides or both. These chemicals are produced inside the cell and are extruded onto the cell's surface.
The_______ is a sticky, gelatinous substance that helps keep many prokaryotic cells from drying out.
glycocalyx
Which of the following is an example of a polysaccharide?
glycogen
Cell surface markers composed of both carbohydrate and lipid molecules are known as ________.
glycolipids
The accumulation of glucose 6-phosphate inside a bacterial cell via phosphorylation of glucose is an example of
group translocation
Which of the following is unique to archaea?
hami
In this chapter, you will learn about an idea called the endosymbiotic theory. By calling this idea a theory, scientists mean that it __________.
has been tested extensively or is supported by many observations
Amphitrichous bacteria ___________________.
have a flagellum at either end of the cell.
Which of the following are structures that make up the flagella? hook cell membrane basal body cell wall rod filament
hook basal body rod filament
The DNA double helix is held together by ________ bonds.
hydrogen
The double helix of DNA is the result of (covalent/ionic/hydrogen) bonds.
hydrogen
A cell can cause a change in the pH of its surroundings by movement of which of the following? carbon atoms nitrogen atoms hydrogen ions sodium ions
hydrogen ions
A chemical reaction in which a water molecule is a reactant is known as a(n) __________ reaction.
hydrolysis
Which of the following is an incorrect pairing?
hydrolysis: hydrogen bonds
The reverse of a dehydration synthesis reaction is a(n) ________ reaction.
hydrolytic
The phospholipids commonly found in the cell membrane contain regions with which of the following characteristics? hydrophobic hydrophilic hydrophobic and hydrophilic hydrophilic and ionic
hydrophobic and hydrophilic
What characteristic contributes to the membrane's ability to block the passage of some molecules? hydrophobic cores availability of ATP electrically neutral surface presence of proteins in the membrane hydrophilic cores
hydrophobic cores
Crenation, the shriveling of cells due to loss of water, occurs when cells are placed in what kind of solution?
hypertonic Hypotonic solutions contain less solute than the inside of the cell, causing cells to gain water.
In a(n) ________ solution, an animal cell can gain so much water that it may burst.
hypotonic
What are porins?
integral proteins, called porins, form channels through BOTH leaflets of the outer membrane, allowing glucose and other monosaccharieds to move across the membrane.
An anion becomes a(n) (anion/ion/cation) when it loses an electron to a more electronegative molecule.
ion
Tertiary and quaternary structure of proteins involves ________ bonds
ionic, hydrogen, polar, and nonpolar covalent
A glycoprotein
is a type of peripheral protein above that can be used as a receptor or in enzymatic functions.
Glycoproteins
is a type of peripheral protein above that can be used as a receptor or in enzymatic functions.
When the nucleus of an atom contains a constant number of protons but a variable number of neutrons, the atom is called a(n) __________.
isotope
The ________ of an element vary in the number of neutrons in the nucleus.
isotopes
Methane is classified as a compound because __________.
it contains atoms of more than one element
Pure water has a neutral pH because __________.
it dissociates into equal numbers of hydrogen and hydroxyl ions
ATP is not required in passive transport of a chemical because ________________________________.
it occurs along that chemical's concentration gradient.
Passive transport does not require ATP because _________________________________.
it occurs along the electrochemical gradient.
Which of the following is NOT a component of peptidoglycan? lipid A NAG amino acid NAM
lipid A Peptidoglycan molecules are composed of NAG, NAM, and amino acids that are grouped together to form a tetrapeptide. Lipopolysaccharide and lipid A are found in the outer membrane of the Gram-negative cell wall.
Which of the following would you expect to be present in a molecule called a lipopolysaccharide? lipid and protein carbohydrate and protein lipid and carbohydrate carbohydrate and nucleic acid
lipid and carbohydrate
Which of the following is NOT a component of peptidoglycan? NAM NAG amino acids lipopolysaccharide (LPS)
lipopolysaccharide
The bacterial cell wall of a Gram-negative bacterium has relatively thin layer of peptidoglycan and an outer membrane composed of________ , phospholipids, and proteins.
lipopolysaccharide (LPS)
Slime layer
loosely attached to cell surface, water soluble, sticky layer allows prokaryotes to attach to surface as biofilms.
Which of the following refers to a bacterium with a tuft of flagella at one end of the cell?
lophotrichous
A cell in a hypertonic solution will __________. gain solutes lose water gain water neither gain nor lose water
lose water
A higher concentration of solutes corresponds to a ________ (higher/lower) concentration of water in a given solution.
lower
Which of the following organelles breaks down worn-out organelles?
lysosomes
What carries instructions for making proteins from the nucleus into the cytoplasm?
mRNA
The glycocalyx of microbial cells has all of the following functions EXCEPT __________. making a microbe more vulnerable to phagocytosis keeping the microbe from drying out providing a mechanism of attachment for the microbe enhancing the ability of pathogenic microbes to colonize surfaces
making a microbe more vulnerable to phagocytosis A glycocalyx makes a microbe too slippery for a phagocyte to engulf.
Where in a cell is ATP made?
mitochondria
The endosymbiotic theory is one possible explanation for the origin of which of the following organelles? peroxisomes centrioles Golgi body mitochondria
mitochondria Both chloroplasts and mitochondria are organelles thought to have arisen through the process of endosymbiosis.
What is endosymbiotic theory?
mitochondria and chloroplasts are semiautonomous, that is they divide independently of the cell but remain dependent on the cell for most of their proteins. The presence of circular DNA, 70S ribosomes, and two bilipid membranes in these semi autonomous organelles led scientist to the endosymbiotic theory for the formation of eukaryotic cells. This theory suggest that eukaryotes formed from the union of small aerobic prokaryotes with larger anaerobic prokaryotes. The smaller prokaryotes were not destroyed by the larger cells but instead became internal parasites that remained surrounded by a vesicular membrane of the host.
Which of the following organelles is often described as the "powerhouse of the cell"? nucleus Golgi body mitochondrion endoplasmic reticulum
mitochondrion
Once equilibrium is reached,
molecules move, but there is no net movement in a particular direction.
An amino acid is an example of a:
monomer
Adenosine triphosphate (ATP) is a:
monomer.
What is Taxis and what are the 2 types?
movement in response to a stimulus is termed taxis. Phototaxis- light. Chemotaxis- chemical stimulus. Movement toward a favorable stimulus is positive taxis. whereas movement away from an unfavorable stimulus is negative taxis. For example, movement toward a nutrient would be positive chemotaxis
Which of the following is NOT a primary function of fimbriae? enhancing a microbe's ability to cause disease creation of biofilms adherence to surfaces movement toward chemicals or light
movement toward chemicals or light
Which of the following is NOT a primary function of fimbriae? creation of biofilms enhancing a microbe's ability to cause disease adherence to surfaces movement toward chemicals or light
movement toward chemicals or light Fimbriae are used by bacteria to adhere to surfaces; in doing so, they are useful in the creation of biofilms and are responsible for the ability of many microbes to cause disease.
Taxis is
movement towards or away from a stimulus.
Taxis is movement towards or away from a stimulus. another term for bacterial tumbling. caused by the undulating motion of a bacterium. another word for stimulus.
movement towards or away from a stimulus.
Which of the following chemical substances contributes to the unique characteristics of acid-fast bacteria?
mycolic acid
diffusion-
net movement of a chemical down its concentration gradient-that is, from an area of higher concentration to an area of lower concentration. in the case of diffusion into or out of cells, only chemicals that are small or lipid soluble can diffuse through the lipid portion of the membrane. Oxygen, carbon dioxide, alcohol and fatty acids can freely diffuse through the cytoplasmic membrane but molecules such as glucose and proteins cannot.
peroxisomes
neutralization of toxins. vesicles derived from ER. contain oxidase and catalase, which are enzymes that degrade poisonous metabolic wastes (such as free radicals ad hydrogen peroxide) found in all types of eukaryotic cells but are especially prominent in the kidney and liver cells of mammals.
Which of the following is a particle that is found in the nucleus of an atom and has no electrical charge?
neutron
Which of the following subatomic particles does NOT have a charge?
neutrons
cilia
no prokaryotes have cilia. composed primarily of tubulin microtubules. 9+2 arrangement of pairs in their shafts and a 9+0 arrangement of triplets in their basal bodies.
The genetic material of a bacterial cell is contained within a region called the_______ .
nucleoid Bacterial DNA is not surrounded by membrane but is in a region of the cytosol.
The monomer of a nucleic acid is called a(n) ________.
nucleotide
Which one of the following structures is/are associated with protozoa? nucleus peptidoglycan pseudopodia nucleus and pseudopodia
nucleus and pseudopodia
Which of the following components of the bacterial cell wall is found in varying amounts in both Gram-positive and Gram-negative cells? lipopolysaccharide teichoic acids endotoxin peptidoglycan
peptidoglycan
what are uniport proteins?
only on substance is transported at a time
plaque
oral bacteria colonize the teeth as a biofilm called plaque. The bacteria in the biofilm produce acid and cause dental caries (cavities)
The diffusion of water across a semipermeable membrane is the process called____ .
osmosis
Which of the following is the most alkaline pH?
pH 13.0
A polymer composed of simple sugars is a(n):
starch.
Another name for a channel protein in the cell membrane is ________.
permease
Which of the following organelles is involved in the degradation of toxic molecules? lysosome peroxisome endoplasmic reticulum Golgi body
peroxisome
The process of bringing a solid substance into the cell is known as ____________________.
phagocytosis
Lipids found in the membranes of all eukaryotic cells are
phospholipids
Which of the following types of lipid is/are the major component(s) of the cytoplasmic membrane? phospholipids sterols triglycerides waxes
phospholipids The amphipathic nature of phospholipid molecules makes them ideal components of a barrier in an aqueous environment, such as that of the cytoplasmic membrane.
chloroplast
photosynthesis, light harvesting structures found in photosynthetic eukaryotes. 2 phospholipid bilayer membranes and DNA
Which of the following has NOT yet been discovered in the archaea? glycocalyces flagella fimbriae pili
pili
What structure acts as a selective barrier, regulating the traffic of materials into and out of the cell?
plasma membrane
Amylose is a(n) __________ carbohydrate.
polymer
DNA is composed of repeating units of sugars, phosphates and nucleic acids. This is an example of a:
polymer.
Which of the following is an INCORRECT pairing? polysaccharide: starch cholesterol: lipid polypeptide: nucleic acid polysaccharide: sugar
polypeptide: nucleic acid A polypeptide is a long chain of amino acids, the building blocks of proteins.
Which of the following terms refers to a bacterium moving toward a carbon source for food? positive phototaxis negative chemotaxis negative phototaxis positive chemotaxis
positive chemotaxis
A bacterial cell moving toward light would be an example of
positive phototaxis.
Compare and contrast prokaryotes and eukaryotes.
prokaryotes; the distinctive feature is that they can make proteins simultaneously to reading their genetic code because a typical prokaryote does not have a membrane surrounding its genetic material (DNA). In other words, a typical prokaryote does not have a nucleus. euk- have a membrane called a nuclear envelope surrounding their DNA, forming a nucleus. Greek word meaning true nucleus. Euk also have numerous other internal membranes that compartmentalize cellular functions. These compartments are membrane bound organelles-specialized structures that act like tiny organs to carry on the various functions of the cell. larger and more complex than prokaryotes, which are typically 1.0 um in diameter or smaller as comared to 10-100 um for eukaryotic cells.
What does the endosymbiotic theory not explain?
provides no explanation for the two membranes of the nuclear envelope, nor does it explain why most of the organelles proteins come from nuclear DNA and cytoplasmic ribosomes .
Which of the following is found in nucleic acids?
purines
Peripheral proteins are involved in _______________.
receptors. recognition sites. enzymatic function.
Which of the following statements concerning the characteristics of life is FALSE?
reproduction is defined as an increase in the size of an organism.
Which of the following statements concerning the characteristics of life is FALSE? organisms may not exhibit all of the characteristics of life at all times. reproduction can occur asexually or sexually in living things. reproduction is defined as an increase in the size of an organism. living things store metabolic energy in the form of chemicals such as ATP. viruses have some, but not all, of the characteristics of living things.
reproduction is defined as an increase in the size of an organism.
active-
require energy. require the cell to expend energy stored in ATP molecules to move material across the cytoplasmic membrane against their electrochemical gradient. Analogous to moving water uphill. active processes in bacteria are active transport and group translocation
What are endospores resistant too?
resistant to drying, heat, radiation and lethal chemicals. endospores are stable resting stages that barely metabolize. they are essentially in a state of suspended animation, and they germinate only when conditions improve. The double membrane, spore coats, dipicolinic acid, calcium, and DNA-binding proteins serve to stabilize DNA and enzymes, protecting them from adverse conditions.
Cells engaging in taxis are exhibiting which of the following basic processes of life? reproduction responsiveness metabolism growth
responsiveness
Using a microscope, you observe an amoeba moving toward a food source. This is an example of
responsiveness
The archaea are similar to bacteria in all of the following aspects EXCEPT __________. their lack of membranous organelles their mechanism of cell division their ribosomal proteins their cytoskeleton
ribosomal proteins
PHB is NOT associated with which of the following words?
ribosome
Which of the following is NOT a membranous organelle within a eukaryotic cell? Which of the following is NOT a membranous organelle within a eukaryotic cell? chloroplast nucleus ribosome endoplasmic reticulum
ribosome
One of the ways smooth endoplasmic reticulum (ER) differs from rough endoplasmic reticulum is that rough ER is covered by
ribosomes
Which of the following organelles is present in both prokaryotic and eukaryotic cells? ribosomes nucleus mitochondria endoplasmic reticulum
ribosomes All cells make proteins, so all cells must have ribosomes.
Polypeptides are assembled by special cellular structures called __________.
ribosomes Ribosomes are important organelles that all cells use to synthesize proteins.
nonmembranous organelles:
ribosomes, cytoskeleton, centrosome
fimbriae
rodlike proteinaceous extensions. Sticky, bristle like projections adhere to one another and to substances in the environment. They may be hundreds of fimbriae per cell and they are usually shorter than flagella. fimbriae serve an important function in biofilms, slimy masses of microbes adhering to substrate by means of fimbriae and glycocalyces. Some fimbriae act as electrical wires, conducting electrical signals among cells in a biofilm. estimated that at least 99% of bacteria in nature exist in biofilms.
Bacteria _______________________. move by undulating the flagella. move by undulating the entire cell. rotate the flagella 360 degrees to move through their environment. only make runs moving toward a stimulus.
rotate the flagella 360 degrees to move through their environment.
Which of the following organelles is involved in producing and transporting proteins throughout the cell? ribosomes Golgi body rough endoplasmic reticulum smooth endoplasmic reticulum
rough endoplasmic reticulum The Golgi body is involved in transporting proteins but does not produce them.
Which of the following organelles is involved in producing and transporting proteins throughout the cell? smooth endoplasmic reticulum rough endoplasmic reticulum Golgi body ribosome
rough endoplasmic reticulum The endoplasmic reticulum plays a role in protein synthesis and transport.
Which of the following is an incorrect pairing?
secondary structure: disulfide bridges
nucleoplasm
semi-liquid matrix of the nucleus, within the nucleoplasm may be one or more nucleoli, which are specialized regions where RNA is synthesized. Nucleoplasm also contains the chromatin, which is a threadlike mass of DNA associated with special proteins called histones that play a role in packaging nuclear DNA.
cytoplasim
semiliquid portion of the cell
The Gram stain is used for which of the following? demonstrate the presence or absence of a nucleus in a cell separate bacteria into two large subgroups disinfect microbiology laboratory materials prove that a particular bacterium causes a particular disease
separate bacteria into two large subgroups
Which of the following is NOT a basic process of life? growth sexual reproduction metabolism responsiveness
sexual reproduction
Which of the following methods of passive transport does not require a permease? simple diffusion osmosis nonspecific facilitated diffusion specific facilitated diffusion
simple diffusion osmosis While water transport can be assisted via a transport protein, water still can diffuse directly across the cell membrane.
What are antiports proteins?
simultaneously transport two chemicals, but in opposite directions, that is, one substance is transported into the cell at the same time that a second substance is transferred out of the cell
Which of the following molecules would be expected to cross the cytoplasmic membrane rapidly and without the use of transport proteins?
small hydrophobic molecules
Which of the following kinds of molecules would be expected to cross the cytoplasmic membrane by diffusion alone? only small molecules only electrically charged molecules only lipid-soluble molecules small, lipid-soluble molecules
small, lipid-soluble molecules
What is exocytosis?
solely eukaryotic process, enables substances to be exported from the cell
What are teichoic acids?
some teichoic acids are covalently linked to lipids, forming lipoteichoic acids that anchor the peptidoglycan to the cytoplasmic membrane. Teichoic acids have negative electrical charges, which help give the surface of a Gram positive bacterium a negative charge and may play a role in the passage of ions through the wall. The thick cell wall of a Gram positive bacterium retains the crystal violet dye used in the Gram staining procedure
Integral proteins _________________________. may have polysaccharides attached to them. can be used in transport of molecules. span the entire lipid bilayer. span the entire lipid bilayer AND can be used in transport of molecules. are found on one side of the cell membrane.
span the entire lipid bilayer AND can be used in transport of molecules.
pili
special type of fimbriae, also called conjugation pilus. Pili aare longer than other fimbriae but usually shorter than flagella. typically only have one to a few pili present per cell in bacteria that have them. Cells use pili to transfer DNA from one cell to the other via a process termed conjugation.
Bacterial pili can be described as
specialized fimbriae.
Describe common shapes and arrangements of bacterial cells.
spherical cells, called cocci, may appear in various arrangements, including singly or in chains, (streptococci), clusters (staphylococci), or cuboidal packets (sarcinae) depending on the planes of cell division. Rod shaped cells, called bacilli, typically appear singly or in chains.
Axial filaments are found on
spirochetes
Some __________ are used as hormones.
steroids
Which of the following is NOT a component of eukaryotic cell walls? cellulose silicates chitin sterols
sterols
Which of the following types of lipid helps keep eukaryotic cell membranes flexible at low temperatures? waxes phospholipids sterols triglycerides
sterols At low temperatures, eukaryotic cell membranes without sterols quickly become gel-like and stiff.
vesicles
storage, digestion, transport
A(n) ________ is a carrier protein that transports two substances in the same direction across a membrane.
symport
Diffusion is used in which type of active transport?
symport
What type of transport uses two transport proteins?
symport
What type of transport uses two transport proteins? uniport antiport symport #2 and #3 all of the above
symport
Which of the active transport types employs diffusion?
symport
Which type of active transport protein is an example of coupled transport?
symport
Which type of active transport protein is an example of coupled transport? uniport antiport symport #2 and #3 all of the abov
symport
The folding of a polypeptide into a three dimensional shape is its (secondary/tertiary/quaternary) structure.
tertiary
The folding of a polypeptide into a three-dimensional shape is its ________ structure.
tertiary
Motility is _____________________________.
the ability of an organism to move by itself.
Bacteria of the genus Mycoplasma are distinguished from other bacterial cells by
the absence of a cell wall.
When a bacterial flagellum turns clockwise, ______________________.
the bacterium "tumbles."
what is a concentration (chemical) gradient?
the difference in concentration of a chemical on the two sides of a membrane
Osmosis is _______________________________.
the diffusion of water.
Tumbles occur when
the flagella rotate clockwise.
Peritrichous bacteria make a run when
the flagella turn counterclockwise and become bundled.
An atom is electrically neutral when
the number of electrons equals the number of protons
In discussions of atomic mass, electrons are often ignored because __________.
their mass makes a negligible contribution to the atom's overall mass
The archaea are similar to bacteria in all of the following ways EXCEPT __________.
their ribosomal proteins
the following are the characteristic of saturated fats
they are found in animals. they are a form of stored energy. their fatty acids pack tightly together. they are usually solid at room temperature
All of the following bases are found in RNA molecules
uracil. guanine. adenine. cytosine
the following are the characteristic of phospholipids?
they contain a hydrophilic phosphate "head." they contain two fatty acids and a phosphate functional group. they are found in cellular membranes. they can form micelles and bilayers
Which of the following is NOT a characteristic of saturated fats?
they contain at least one double bond.
Which of the following is NOT a characteristic of phospholipids?
they contain fatty acids that associate with water.
what is chromatin
threadlike mass of DNA associated with special proteins called histones that play a role in packaging nuclear DNA.
Hydrophobic molecules would enter a cell
through integral transport proteins.
Organisms use carbohydrates in all of the following ways EXCEPT
to keep membranes flexible at low temperatures
What is tonicity?
tonicity is used when talking about the response of cells
antiport proteins
transfer 2 types of molecules but in opposite directions
symport, coupled proteins
transport 2 different molecules at the same time but is coupled with a uni port channel
Integral proteins are mostly involved in
transport function
endoplasimc reticulum
transport within the cell, lipid synthesis. SER; plays a role in lipid synthesis as well as transpor. RER is rough because he ribosomes adhere to its outer surface. Proteins produced by ribosomes on the RER are inserted into the lumen (central canal) or the RER and transported throughout the cell
Which of the following bacteria would have axial filaments? streptococci found in a yogurt culture rod-shaped bacilli in the human gut treponema spirochetes in a syphilis chancre staphylococci found on the skin
treponema spirochetes in a syphilis chancre
Which of the following is NOT a component of bacterial flagella?
tubulin
Which of the following is NOT a component of bacterial flagella? hook tubulin flagellin filament basal body
tubulin
what are symports?
two substances move together in the same direction across the membrane by means of a single carrier protein called a symport
Efflux pumps can be used to pump antibiotics out of a cell once they enter to protect the cell. This will be done against the concentration gradient of the antibiotic. Which of the active transports would most likely be used?
uniport
Which type of active transport transports only one type of material?
uniport
A uniport channel is used in which type of active transport system?
uniport and symport
Which of the following would NOT normally be found as a component of a cell's nucleic acids?
uracil deoxyribonucleotides
In the symbol R-OH, the "R" stands for the _______________ part of the molecule.
variable
hypotonic-
water concentration is higher so water moves into the cell and the cell grows
The presence of __________ in the cell wall of a microbe causes it to be resistant to drying.
waxes
Bacterial cell walls that are resistant to drying contain
waxes.
A bacterium tumbles ___________________. when the flagella rotate counterclockwise. more frequently as it moves toward a negative stimulus. when the flagella rotate clockwise. more frequently as it moves toward a positive stimulus.
when the flagella rotate clockwise.
A positively charged sodium ion
would require the use of integral protein channels to pass through a cell membrane.
