Microbiology-Chapter 7 & 8
True or false: The Calvin cycle is part of the light-dependent reactions of photosynthesis.
False Reason: The Calvin cycle occurs in the light-independent reactions.
Glycolysis is an example of which metabolic pattern?
Linear
Which method of cell division do prokaryotic cells perform?
Binary fission
____ pathways couple catabolic metabolic pathways with anabolic metabolic pathways.
Blank 1: Amphibolic or Amphibolism
____ is a set of reactions needed to break down organic molecules into materials while ____ is the set of reactions that use these materials to build larger, more complex molecules.
Blank 1: Catabolism or Catabolic Blank 2: anabolism or anabolic
An ____ is a microorganism that can use gaseous oxygen in its metabolism and possesses enzymes needed to process toxic oxygen products.
Blank 1: aerobe or aerobic organism
The incomplete breakdown of glucose in the absence of oxygen that yields only a small amount of ATP and produces a variety of byproducts is a process called .
Fermentation
Which term describes the incomplete breakdown of glucose due the absence of an electron acceptor for the electron transport system?
Fermentation
What do the letters of ATP represent?
adenosine triphosphate
A series of reactions that converts glucose to CO2 and allows the cells to recover significant energy in the form of ATP is known as ______.
aerobic respiration
The ultimate source of all chemical energy on Earth is the ____ , making most organisms directly or indirectly dependent on photosynthesis.
sun
If human red blood cells are placed in a vial of pure water, _______.
the net water movement is into the cell
In a metabolic pathway, ______ and ______.
the product of one reaction is often the substrate for another branches provide alternate methods for nutrient processing
The ultimate source of energy on Earth is ______.
the sun
The term ____ describes the appearance of a cloudy broth culture.
turbidity
Most microbes prefer environments near or at a pH of
7
Anabolic reactions produce ATP to create new molecules.
False
Like budding, binary fission produces two differently sized cells that contain an equal amount of genetic information.
False
True or false: Both aerobic and anaerobic respiration use oxygen as the final electron acceptor.
False
Select the statement that accurately characterizes ATP.
It contains three phosphate molecules.
True or false: Photosynthetic microbes are not damaged by electromagnetic radiation.
False
Which term is used exclusively to describe water's movement across a selectively permeable membrane?
Osmosis
____ is the diffusion of water across a selectively permeable membrane in the direction of lower water concentration.
Osmosis
When an inhibitor mimics the substrate and occupies the active site of the enzyme, this is referred to as ______ inhibition.
competitive
How many ATP molecules are produced by oxidative phosphorylation for each glucose that enters glycolysis?
34
Which of the following can synthesize all the macromolecules from CO2 and minerals?
Autotrophs
The Calvin cycle is ____.
dependent on the products from the light-dependent reactions to work
You release a small drop of methylene blue dye into a beaker of water and watch the diffusion of the methylene blue from regions of ______ concentration to regions of ______ concentrations of dye.
"high" to "low"
In ____ respiration, oxygen is the terminal electron acceptor.
Blank 1: aerobic
What term is used to describe a graphical representation of a change in population size over time?
Growth curve
Common electron carriers include
NAD FAD
What word describes a microbe that must have oxygen to survive?
Obligate aerobe
What type of microbial association is depicted in this figure?
Synergism
Antibiosis is a form of:
antagonism
The type of microbial metabolic pathway that is most often exploited to make acids and alcohols industrially is ______.
fermentation
P680 is associated with ______.
photosystem II
Assuming the concentration of a solution is homogeneous, the movement of molecules following the properties of diffusion is ______.
random
Select all that apply Which two of the following statements regarding heterotrophs are true?
-Large organic molecules (like starch, a polymer of glucose) must be digested before absorption. -Monosaccharides are generally good carbon sources for heterotrophs.
Select all that apply Which two of the following statements regarding heterotrophs are true?
-Some heterotrophs are restricted to just a few carbon substrates. -Amino acids may be a good carbon source for a heterotroph.
Select all of the products of glycolysis to test your understanding of this process.
2 ATP (net) 2 pyruvic acids 2 NADH H2O
Using the equation Nf = Ni (2n), determine how many Staphylococcus aureus cells are present in a custard tart under these circumstances. During preparation, 15 cells were deposited in the custard, and the tart has sat at room temperature for 5 hours. S. aureus has a generation time of 20 minutes.
4.9 x 10⁵ cells
Most organisms are neutrophiles, growing in habitats between pH ______.
6 and 8
Consider the following hypothetical conditions: A population of 10,000 bacteria has a doubling time of 20 minutes under a given set of growth conditions. The culture is allowed to grow for 2 hours. Select the number of bacteria that best predicts the population size at the end of the two hour incubation period. Assume there is no lag phase.
640,000
What word is used to describe organisms which can use oxygen in their cellular respiration pathways?
Aerobic
Which term is used to describe the integration of anabolic and catabolic pathways?
Amphibolism
What term is used to describe organisms that can generate their own food from inorganic compounds?
Autotrophs
A(n) ____ is an organism that requires only inorganic nutrients and carbon dioxide as a sole carbon source.
Blank 1: lithoautotroph, chemoautotroph, chemolithotroph, autolithotroph, autotroph, chemolithoautotroph, or autotrophs
The ____ temperature is the lowest temperature at which an organism will grow.
Blank 1: minimum, minimal, or minimum growth
The location of the Krebs cycle enzymes in eukaryotes is in the ____ matrix, while in prokaryotes the enzymes are found in the ____ .
Blank 1: mitochondria, mitochondrion, or mitochondrial Blank 2: cytoplasm or cytosol
In aerobic respiration, ____ serves as the final electron acceptor.
Blank 1: oxygen, free oxygen, or O2
The term "metabolism" includes which type(s) of cellular reactions?
Both anabolic and catabolic
Which of the following acronyms is used to describe the collection of elements which compose 96% of a cell?
CHONPS
Select all that apply About 96% of the cell is composed of which elements?
Carbon Phosphorous Hydrogen Sulfur Nitrogen Oxygen
Select the statement that most accurately reflects the Calvin cycle.
Carbon fixation is an important step in this cycle.
From the list below, select all of the active transport mechanisms used by cells.
Carrier mediated Group translocation Endocytosis
Which enzyme converts hydrogen peroxide, formed in aerobic respiration, to water and oxygen?
Catalase
Which of the following is defined as a relationship between organisms where one benefits and the other is unharmed?
Commensalism
____ is a type of symbiotic relationship between two organisms in which one species derives benefit without harming the other.
Commensalism
Match the term to the phrase that most accurately describes it to test your understanding of enzyme terminology.
Endoenzyme-Enzymes which function inside a cell Constitutive Enzyme-Enzymes which are always present in a cell in relatively constant amounts Regulated-The production of these enzymes can be turned on or off as needed Exoenzyme-Enzymes which are secreted and function outside a cell
Indicate the direction of movement of the molecules in this diagram of active transport.
From left to right
Which term describes the length of time of a microbial species needs to divide?
Generation time
Which statement accurately reflects the Krebs cycle?
It produces 8 reduced coenzymes per glucose molecule.
What is the typical "next step" for pyruvate at the end of glycolysis following normal aerobic or anaerobic respiration?
Krebs cycle
Which is FALSE regarding binary fission?
Like meiosis in eukaryotes, it specifically produces daughter cells with genetic variation.
Select the characteristics of biofilms that differentiate them from planktonic bacteria. Check all that apply.
Microorganisms participate in quorum sensing. Microorganisms secrete extracellular material, usually polysaccharide, that forms a matrix. Microorganisms exist as part of a diverse interdependent community.
Which term describes the lowest temperature at which a microbe can grow?
Minimum temperature
______ is the acquisition of chemical substances by organisms for use as an energy source or as building blocks of cellular structures.
Nutrition
Match the term with the appropriate description to test your understanding of the diversity of oxygen requirements among microorganisms.
Obligate Aerobe-Describes an organism which requires oxygen for growth and has the enzymes to remove toxic by-products of oxygen metabolism Aerotolerant Anaerobe-Describes an organism that can grow in the presence of oxygen and can detoxify it, but can also grow in the absence of oxygen Microaerophile-Describes an organism that can't grow at normal atmospheric oxygen concentrations, but does require a small amount of oxygen for growth Obligate Anaerobe-Describes an organism that is unable to use oxygen and lacks the enzymes to detoxify oxygen, thus requiring the absence of oxygen for growth Facultative Anaerobe-Describes an organism that does not use oxygen, but can grow to a limited extent in the presence of oxygen
What term describes an organism that lacks superoxide dismutase and catalase enzymes?
Obligate anaerobe
Which term describes a microbe that grows in a habitat with a high solute concentration?
Osmophile
What term is used to describe photosynthesis reaction which produce oxygen as a waste product?
Oxygenic
Move the terms to their correct category to test your understanding of transport processes in cells.
Passive Transport-Simple Diffusion, Facilitated Diffusion Active Transport-Carrier-mediated transport, group translocation, phagocytosis, pinocytosis
____ occurs to a bacterial cell when it loses water due to an environment that has far more solutes outside the cell compared to inside.
Plasmolysis
Drag the labels to complete each of the sentences that discuss the source of essential nutrients available to microbes.
Regardless of an organism's ability to reside in seemingly inhospitable conditions, all cells require certain nutrients for survival. How they obtain those nutrients varies from organism to organism, and there is no greater versatility than the ability of bacteria to harness chemicals from a variety of sources. CHONPS is the acronym used to describe the list of essential nutrients required by all organisms for survival. Heterotrophs differ from autotrophs in how they obtain their source of carbon; heterotrophs must rely on other organisms to provide them with organic molecules such as proteins and nucleic acids, whereas autotrophs are able to 'fix' carbon from inorganic CO₂, making them nutritionally independent. Nitrogen is essential for the formation of proteins, nucleic acids, and the source of cellular energy, ATP. The main reservoir of earth's nitrogen is in the form of N₂ gas, which is unavailable for cellular use. A few species of bacteria can carry out nitrogen fixation which converts gaseous nitrogen into a usable form. As with carbon, heterotrophs must obtain their nitrogen from the organic molecules of other organisms. Phosphorus, essential for the formation of membranes, nucleic acids, and ATP, as well as sulfur, necessary for certain amino acids, must be harnessed from mineral deposits in rocks and oceans.
Enzymes that can be shut down or activated based on the presence of chemicals in their environment are called _______.
Regulated
Analyze the statements below, and select those that correctly apply to the feeding mechanisms of saprobes and parasites.
Saprobes with a rigid cell wall must excrete extracellular enzymes into their surroundings in order to digest large organic molecules before ingestion. The term saprobe applies to those organisms that feed by decomposing dead, organic matter whereas parasites derive their nutrients from a living host. Some saprobes are strict decomposers, whereas others can infect a susceptible host, becoming opportunistic pathogens.
From the list below, select all of the passive transport mechanisms used by cells.
Simple diffusion Facilitated diffusion
Match the phase of the bacterial growth curve with its description.
Stationary Growth Phase-Phase during which nutrient depletion and accumulation of wastes begin to slow cell growth such that the rate of cell increase equals the rate of cell death Exponential Growth Phase-Phase during which cells are growing very quickly, at their maximum rate of cell division Lag Phase-Adjustment period during which cells are dividing slowly while they adjust to growth conditions Death Phase-Nutrient depletion and waste accumulation prevent cell growth and cells die exponentially
Choose the statement that best describes the role of the Calvin cycle in photosynthesis.
The Calvin cycle is the "synthesis" part of photosynthesis, the set of reactions that actually convert CO2 to organic carbon compounds.
True or false: Autotrophs can synthesize all macromolecules from carbon dioxide and minerals.
True
True or false: In cells, the biosynthesis of carbohydrates is ensured by several alternative pathways.
True
True or false: In strict aerobes and some anaerobes, pyruvic acid enters the Krebs cycle after it is converted to acetyl CoA.
True
True or false: In strict aerobes and some anaerobes, pyruvic acid enters the Krebs cycle after it is converted to acetyl CoA. True false question. True
True
True or false: Nutrition is the acquisition of chemical substances by organisms for use as an energy source or as building blocks of cellular structures.
True
True or false: P680 refers to photosystem II.
True
What term is used to describe the cloudiness of a broth culture?
Turbidity
Electron carriers like NAD and FAD repeatedly ______.
accept and release electrons
Select all that apply Cellular growth can be visualized by:
an increase in cell number an increase in cell size an increase in cellular components
Reactions that use energy and synthesize building blocks into macromolecules are part of _______, whereas ______ refers to cellular reactions that break larger molecules into smaller molecules and release energy.
anabolism; catabolism
In ____ respiration, oxygen is not the terminal electron acceptor.
anaerobic
The letters in ATP represent the words
andenosine triphosphate
Electron carriers _______.
become reduced when they receive electrons
Bacteria reproduce by ____ fission.
binary
Prokaryotic cells divide by a process called .
binary fission
Select all that apply A microbe's nutritional type (e.g., chemoheterotroph) is determined by its sources of ______ and ______.
carbon energy
Glycolysis is a(n) ______ process, which breaks down glucose into smaller molecules.
catabolic
The enzyme ____ converts hydrogen peroxide formed during aerobic respiration to water and oxygen.
catalase
The bacterial cell structure specialized for transport is the ______.
cell membrane
Which descriptors are likely to have applied to the earliest microbes on the planet? Check all that apply.
chemoautotrophic chemoheterotrophic
In terms of energy and carbon sources, deep-sea vent microorganisms and methanogens are most specifically classified as ______.
chemoautotrophs
A(n) _______ is a biological catalyst.
enzyme
Composed principally of amino acids, ______ act as biological catalysts, facilitating metabolic activities of the cell.
enzymes
A reaction that releases energy is termed ______.
exergonic
Penicillinase, streptokinase, and collagenase are examples of ______. Multiple Choice
exoenzymes
In binary fission, the doubling time of a particular microbial species is also known as its ____ time.
generation
A curve is a graphical representation of the change in population size over time.
growth
Select all that apply Which two of the following are transport functions of the cell membrane?
import nutrients export waste materials
Cellular growth ______.
is stimulated by nutrients and environmental factors
In the first step of lipid catabolism, ______ break the bonds joining the fatty acids to the glycerol. The fatty acids are then converted to a number of acetyl CoA molecules in a process known as beta oxidation.
lipases
In active transport, molecules are moving across the membrane from an area of ______ concentration to an area of ______ concentration.
low; high
Carbon, nitrogen, oxygen and hydrogen are considered _______ because they are required in relatively large quantities, whereas manganese, zinc, and copper are considered ______ because they are required in very small quantities.
macronutrients; micronutrients
The combination of all reactions (catabolic + anabolic) within a cell is termed ____.
metabolism
The Krebs cycle occurs in the ______ of eukaryotic cells and the ______ of bacteria.
mitochondria; cytoplasm
The final step in the electron transport chain transports electrons to ______ to generate water.
molecular oxygen
A(n) ____ aerobe, or strictly aerobic organism, requires oxygen for survival.
obligate
A(n) ____ is a microorganism that thrives in any hypertonic medium.
osmophile
Diffusion of water through a selectively permeable membrane is referred to as ______.
osmosis
During aerobic respiration of one molecule of glucose, 34 ATP are generated by ____ phosphorylation in the electron transport system.
oxidative
During ____ photosynthesis, chlorophyll-containing organisms produce O2 as a waste product.
oxygenic
A series of metabolic reactions is termed a ______.
pathway
All bacteria can be divided by their energy sources as ______ or ______.
phototrophs; chemotrophs
Some microbes produce ______ to protect themselves against damaging electromagnetic radiation.
pigments
Bacterial cells placed in a solution where the concentration of solute within the cytoplasm is less than that of the extracellular solution would undergo ______.
plasmolysis Reason: Because the cytoplasm has a lower solute concentration, this means the water within the cell is greater than that of the extracellular solution. Therefore, water would flow out of the cell and plasmolysis would occur.
During exergonic reactions, energy is ______.
released
Aerobic respiration includes the following three pathways:
respiratory chain Krebs cycle glycolysis
Label the image to review the major types of microbial associations.
see picture
In cells, the biosynthesis of carbohydrates involves ______.
several alternative pathways
The final step in the electron transport chain produces ______.
water
