1
Q
What is the type of transport that moves solute molecules against a concentration gradient, requiring metabolic energy input?
A
Active transport
2
Q
What is the movement of nutrients from low → high concentration, with the help of permeases or pumps and requiring ATP/ion gradients?
A
Active transport
3
Q
Define Active Transport Mechanism
A
Features of active transport:
- the transport of nutrients against the diffusion gradient -
Movement from low to high concentration - Movement of substances across a membrane with the
assistance of specific membrane proteins (permeases and
pumps) - the expenditure of energy (e.g. ATP or ion gradients) from cell
• Examples of substances transported actively are
monosaccharides, amino acids, organic acids, phosphates, and
metal ions
4
Q
Give two examples of specific membrane proteins used in active transport.
A
Permeases and pumps
5
Q
Name at least three examples of substances transported actively.
A
Monosaccharides, amino acids, organic acids, phosphates, metal ions
6
Q
What are ABC transporters (ATP-binding cassette transporters) active in?
A
Bacteria, archaea, and some eukaryotes
7
Q
What type of active transport involves a soluble cassette protein binding to a target and delivering it to an integral ATPase pump?
A
ATP-binding cassette (ABC) transporter system
8
Q
The target binds to a soluble cassette protein (in
periplasm of gram-negative bacterium, or located
bound to outer leaflet of plasma membrane in grampositive bacterium).
The target-cassette complex then binds to an integral membrane ATPase pump that transports the target across the plasma membrane.
A
ATP-binding cassette transporters
9
Q
What bacterial active transport system uses the simultaneous transport of two substances in opposite concentration gradients (one low → high, the other high → low)?
A
Cotransport system
9
Q
Which active transport system involves chemical modification of the transported molecule during entry?
A
Group translocation
9
Q
Transport of one substance from a
low to high concentration as another substance is
simultaneously transported from high to low.
A
Cotransport systems
10
Q
What is the best-known example of a group translocation system?
A
Phosphoenolpyruvate: sugar phosphotransferase system (PTS)
11
Q
In PTS, what compound donates the phosphate group?
A
Phosphoenolpyruvate (PEP)
12
Q
What are the four main components of the PTS in E. coli?
A
Enzyme I (EI),
HPr (heat-stable protein),
Enzyme II (EII),
Enzyme III (EIII)
13
Q
What specialized low molecular weight organic molecules do bacteria secrete to bind ferric iron (Fe³⁺)?
A
Siderophores
14
Q
Why are siderophores necessary?
A
Because Fe³⁺ has low solubility, making direct uptake difficult
15
Q
Through what transport system is the Fe³⁺-siderophore complex transported back into the bacterial cell?
A
ABC transporter
16
Q
What is the transport process involving vesicles that move large molecules, particles, or fluids into a cell?
A
Endocytosis
17
Q
What is the transport process that expels large molecules or particles out of a cell via vesicles?
A
Exocytosis
18
Q
What type of bulk transport is carried out by amoebas and white blood cells, involving ingestion of whole cells or large solid matter?
A
Phagocytosis
19
Q
What type of bulk transport involves ingestion of liquids such as oils or solutions?
A
Pinocytosis
20
Q
Q: Enumerate the three main types of active transport systems in bacteria.
A
- ATP-binding cassette (ABC) transporters
- Cotransport systems
- Group translocation systems
21
Q
Q: Enumerate the steps/components involved in group translocation PTS.
A
- PEP (phosphate donor)
- Enzyme I (EI)
- HPr (heat-stable protein)
- Enzyme II (EII)
- Enzyme III (EIII)
22
Q
Q: Enumerate the bulk transport processes.
A
- Endocytosis
- Exocytosis
- Phagocytosis
- Pinocytosis
23
24. Q: Compare Passive diffusion, Facilitated diffusion, Active transport, and Group translocation in terms of:
Carrier proteins
Transport speed
Against gradient
Specificity
Energy requirement
Solute modification
**Carrier proteins:**
Passive diffusion – None;
Facilitated diffusion – Yes;
Active transport – Yes;
Group translocation – Yes
**Transport speed:**
Passive – Slow;
Facilitated – Rapid;
Active – Rapid;
Group translocation – Rapid
**Against gradient:**
Passive – No;
Facilitated – No;
Active – Yes;
Group translocation – Yes
**Specificity:**
Passive – No;
Facilitated – Specific;
Active – Specific;
Group translocation – Specific
**Energy requirement:**
Passive – None;
Facilitated – None;
Active – Requires energy;
Group translocation – Requires energy
**Solute modification:**
Passive – Not changed;
Facilitated – Not changed;
Active – Not changed;
Group translocation – Changed
24
Process by which chemical substances (nutrients) are acquired from the environment and used for cellular activities.
Nutrition
25
Any substance that must be provided to an organism because it cannot be synthesized on its own.
Essential nutrient
26
Nutrients required in relatively large quantities that play principal roles in cell structure and metabolism.
Macronutrients
27
Nutrients required in much smaller amounts, often involved in enzyme function and maintenance of protein structure.
Micronutrients (Trace elements)
28
Nutrients containing carbon and hydrogen, products of living things, **e.g., methane, carbohydrates, lipids, proteins, nucleic acids.**
Organic nutrients
29
Atoms or simple molecules containing combinations **other than carbon and hydrogen**; found in crust of Earth, water, atmosphere.
Inorganic nutrients
30
Chemicals necessary for organisms that cannot be manufactured by themselves (abbreviation CHONPS).
Essential nutrients
31
Fundamental macronutrient serving as primary building block for all cellular components and skeleton of organic molecules.
Carbon
32
Primary reservoir of this element is the atmosphere, making up 79% as N2 gas.
Nitrogen
33
Element that must be converted into ammonia (NH3) before it can be combined with carbon to synthesize amino acids.
Nitrogen
34
Element that is a major component of carbohydrates, lipids, proteins, inorganic salts, and water; makes up 20% of atmosphere.
Oxygen
35
Element with roles in maintaining pH, forming hydrogen bonds, and serving as a source of free energy in redox reactions.
Hydrogen
36
Component of phospholipids, DNA, RNA, ATP, and proteins; main source is phosphate from rocks and oceanic minerals.
Phosphorus
37
Element found in rocks, sediments, sulfates, sulfides, and H2S;
forms disulfide bonds critical for protein tertiary structure.
Sulfur
38
Element important for certain types of cell transport.
Sodium
39
Stabilizer of cell wall and bacterial endospores.
Calcium
40
Component of chlorophyll and stabilizer of cell membranes and ribosomes.
Magnesium (Mg)
41
Important component of cytochrome proteins in cell respiration.
Iron (Fe)
42
Essential regulatory element in eukaryotic genetics.
Zinc (Zn)
43
Trace elements sometimes required by microbes:
Cu, Co, Ni, Mo, Mn, Si, I, B.
Give their full names
Copper, cobalt, nickel, molybdenum, manganese, silicon, iodine, boron
44
Enumerate the two categories of essential nutrients.
Macronutrients and Micronutrients (Trace elements)
45
Enumerate examples of macronutrients.
Carbon, oxygen, nitrogen, hydrogen
46
Enumerate examples of organic nutrients.
Methane, carbohydrates, lipids, proteins, nucleic acids
47
Enumerate examples of inorganic nutrients.
Water, salts, metals, gases (except organic gases like methane)
48
26. CHONPS – what does each letter stand for?
Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorus, Sulfur
49
Roles of carbon in microbial nutrition.
Building block of cellular components
Skeleton of organic molecules
Source of oxygen and hydrogen atoms
Energy production and metabolism
50
Sources/forms of nitrogen that microbes can use.
NO3- (nitrate), NO2- (nitrite), NH3 (ammonia), atmospheric N2 (fixed by some bacteria and algae)
51
Roles of oxygen in microbial nutrition.
Component of carbohydrates, lipids, proteins
Structural and enzymatic functions
Component of salts (sulfates, phosphates, nitrates)
Essential to metabolism of many organisms
52
Roles of hydrogen in microbial nutrition.
Maintaining pH
Forming hydrogen bonds
Source of free energy in oxidation-reduction reactions
53
Important functions of phosphorus.
Answer:
Component of membranes (phospholipids)
Component of DNA, RNA, ATP
Energy transfers (ATP)
Essential for genetics
54
Important functions of sulfur.
Found in amino acids (methionine, cysteine)
Forms disulfide bonds in proteins
Component of vitamins (thiamin, biotin)
Stabilizes protein structure
55
Other important elements and their roles.
Na (Sodium): cell transport
Ca (Calcium): stabilizes cell wall and endospores
Mg (Magnesium): chlorophyll, stabilizes membranes and ribosomes
Fe (Iron): cytochromes in respiration
Zn (Zinc): regulatory element in eukaryotic genetics
Others (Cu, Co, Ni, Mo, Mn, Si, I, B): trace functions in some microbes
56
Chemical requirements needed only in small amounts, usually found in sufficient quantities in tap water.
Trace elements
57
Necessary organic chemicals that cannot be synthesized by certain organisms (examples: vitamins, amino acids, purines, pyrimidines, cholesterol, NADH, heme).
Growth factors
58
Organic compounds required in very small amounts, and only by some cells, which include amino acids, purines/pyrimidines, and vitamins.
Growth factors
59
Specific growth factor needed for protein synthesis.
Amino acids
60
Specific growth factors needed for nucleic acid synthesis
Purines and pyrimidines
61
Small organic molecules that usually make up all or part of enzyme cofactors and are required in only very small amounts.
Vitamins
62
Microorganisms that can use CO2 as their sole carbon source via carbon fixation
Autotrophs
63
Microorganisms that **require an organic carbon source** and cannot use CO2 directly.
Heterotrophs
64
Microorganisms that use light as an energy source.
Phototrophs
65
Microorganisms that obtain energy from the oxidation of reduced chemical compounds.
Chemotrophs
66
Microorganisms that use reduced organic compounds as a source for reduction potential (electrons)
Organotrophs
67
Microorganisms that use reduced inorganic compounds as a source for reduction potential (electrons).
Lithotrophs
68
Free-living heterotrophic organisms that feed on organic detritus from dead organisms and act as decomposers.
Saprobes
69
Heterotrophs that derive nutrients from the cells or tissues of a living host.
Parasites
70
Parasites that cause damage to tissues or even death.
Pathogens
71
Parasites that live on the body surface of the host.
Ectoparasites
72
Parasites that live inside organs and tissues.
Endoparasites
73
Parasites that live within host cells, such as Mycobacterium leprae (leprosy bacillus) and Treponema pallidum (syphilis spirochete).
Intracellular parasites
74
Parasites unable to grow outside of a living host.
Obligate parasites
75
The vast majority of microbes causing human disease belong to this nutritional category.
Chemoheterotrophs
76
General process of moving molecules into or out of cells, driven by atomic and molecular movement.
Transport mechanisms
77
Transport of necessary nutrients occurs **across this structure**, even in organisms with cell walls.
Cell membrane
78
Enumerate the three categories of growth factors.
Amino acids, Purines and Pyrimidines, Vitamins
79
Enumerate examples of intracellular parasites.
*Leprosy bacillus* (Mycobacterium leprae), *Syphilis spirochete* (Treponema pallidum)
80
Enumerate the types of parasites.
Answer:
Ectoparasites (on body surface)
Endoparasites (in organs and tissues)
Intracellular parasites (within cells)
Obligate parasites (cannot grow outside host)
81
Enumerate the two kinds of bacterial heterotrophs.
Saprobes, Parasites
82
Enumerate the two categories of organisms based on electron (reduction potential) source.
Organotrophs, Lithotrophs
83
Enumerate the two categories of organisms based on energy source.
Phototrophs, Chemotrophs
84
Enumerate the two categories of organisms based on carbon source.
Autotrophs, Heterotrophs
85
Enumerate the three types of passive transport.
Diffusion, Facilitated diffusion, Osmosis
86
Type of transport that does not require energy; substances move down their concentration gradient.
Passive transport
87
Passive transport process where substances move directly from high → low concentration without proteins.
Diffusion
88
Passive transport process that requires a carrier protein but no energy.
Facilitated diffusion
89
Passive transport process specific to water movement across a selectively permeable membrane.
Osmosis
90
Enumerate the three types of active transport.
Carrier-mediated active transport, Group translocation, Bulk transport
91
Enumerate molecules transported by simple diffusion.
Water (H₂O), Oxygen (O₂), Carbon dioxide (CO₂)
92
Enumerate the conditions that affect diffusion.
Concentration gradient, Permeability of the substance, Temperature
93
Enumerate the mechanisms of facilitated diffusion.
Channel proteins, Carrier proteins (permeases)
94
Enumerate the effects of osmosis on cellular survival.
Water freely enters or exits cells
Imbalance affects cell survival
Osmotic relationship depends on solute concentration
95
Diffusion of water through a selectively or differentially permeable membrane.
Osmosis
96
Another name for carrier proteins in facilitated diffusion.
Permeases
97
Two types of proteins involved in facilitated diffusion.
Channel proteins and Carrier proteins
98
Membranes that allow free diffusion of water but block other solutes.
Selectively permeable membranes
99
Osmosis principle?
Direction of water diffusion when solute cannot pass through: from the side with more water → less water.
100
Condition reached when water concentration is equalized on both sides of a membrane.
Osmotic equilibrium
101
General property of living membranes regarding large molecules?
They block entrance/exit of larger molecules but allow water movement
102
Relationship between a cell and its environment determined by solute concentrations across the membrane is?
Osmotic relationship
103
Living membranes generally block the entrance and exit of larger
molecules and permit the free movement of water
• Most cells are surrounded by some free water and the amount of
water entering or leaving has a major impact on cellular activities
and survival
• This osmotic relationship between cells and their environment is
determined by the relative concentrations of the solutions on
either side of the cell membrane
Osmosis
104
How does osmosis occur?
when the membrane is placed between solutions of differing
concentrations of solute and the solute cannot pass through the
membrane, water will diffuse at a faster rate from the side that
has more water to the side that has less water
- this will continue until the concentration of water is equalized on
both sides of the membrane
Microbiology
flashcards
Decks in class (22)
# Cards
-
Module 6106
-
Module 7181
-
Module 8. 1132
-
Module 8.2115
-
Module 8.3283
-
Module 9188
-
9191
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11.1191
-
11.2170
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Module 11.2160
-
Module 12 (Slide 1 To 39)94
-
Module 12 (Slide 40 To 65)76
-
Module 12 (66-101)156
-
Module 12 (-110 Last)25
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LAB EXAM 1 EXERCISES31
-
LAB EXAM 1 PPT CULTURE MEDIA107
-
Module 13 (VIRUSES)64
-
Module Virology Pt.1 (RNA VIRUSES)85
-
Module Virology Part 2 (DNA)57
-
Module VIROLOGY Part 3 (Introduction)98
-
RNA (Picorna-Coronaviridae)83
-
RNA VIRUS (REO - RHABDOVIRIDAE)49
