MIC205 Exam 1 (modules 1,2,3)
The following structure represents the cell wall of which type of bacteria?
Gram positive
Bacteria increase numbers by a process called ---------------- (2 words)
binary fission
The appendage that allows bacteria to attach to surfaces is called [---------------].
fimbriae
Doubling of bacterial cells is happening in [------------] phase of the bacterial growth curve
log/exponential
The cell wall is a structure that protects the bacterial cell from lysis.
True
The genetic hereditary material (DNA) in eukaryotes is packaged into linear chromosomes that are located in the nucleus, while the prokaryotes have a single, circular, DNA found in the cytoplasm.
True
The following structure represents the cell wall of which type of bacteria?
Gram negative
You are preparing a sandwich at 6:30 AM to take to school with you. You accidentally cough and introduce 10 bacteria into your sandwich as you are making it. Calculate the number of bacteria that will be present when you eat your sandwich at 10:30 am? The sandwich was lying in your locker throughout this time. The generation time (time taken to double the number of cells) of the bacteria is 30 minutes at room temperature. You may use the following chart to help you visualize the problem.
2560
During replication, which of the following is the correct sequence of the daughter DNA strand that is synthesized using 5" CAGTTCGGA 3" as a template?
3" GTCAAGCCT 5"
During transcription, which of the following will be the correct sequence of the RNA strand that is synthesized using 5" CAGTTCGA 3" as a template?
3" GUCAAGCU 5"
Which of the following could be synthesized using the following template? 3" CAGTTCGGA 5"
5" GTCAAGCCT 3"
Which of the following organisms best represent Box 1 in the picture shown below?
Bacteria
According to the endosymbiont theory:
Bacteria are the ancestors of chloroplasts and mitochondria
-------------, -------------, & --------------- are the three domains of life.
Bacteria, archaea, & eukarya
You have discovered a unique organism in the ocean with the following features: It has a cellular structure with circular DNA as its genetic material. The DNA is dispersed in the cytoplasm, but no organelles can be detected within the cell. The entire cell is covered by a cell wall. This organism is most likely a:
Bacterial cell
Viruses have a cellular structure while bacteria are not cellular.
False
The part labeled D helps with motility of the bacterial cell. Identify D .
Flagella
You have discovered an organism that is 0.7 mm in size from a pond. It contains a nucleus. Which of the following conclusions can you make about this organism?
It cannot be classified as a prokaryote (has nucleus)
According to a study published in 2013, prolonged use of antibiotics may lead to disruption of mitochondrial function. Which of the following BEST explains this observation?
Mitochondria are structurally similar to bacteria; therefore, they are susceptible to antibiotics that target bacteria.
[--------------------] is an electron carrier in the cell.
NADH
Which of the following factors influence bacterial growth?
Oxygen Temperature Nutrient availability
Match the following processes shown on the left column with their correct definition or description on the right column
Transcription: synthesis of an RNA molecule from a DNA template Translation: Process by which mRNA is decoded and a protein is produced Replication: Copying process by which a cell duplicates its DNA Mutations: Random errors in gene replication that lead to a change in the sequence of nucleotides. The source of all genetic diversity.
ALL living cells are classified as either Prokaryotes or Eukaryotes.
True
Bacteria were the earliest organisms to produce oxygen on earth.
True
You have discovered a new microorganism that can potentially eradicate a pandemic infection. Based on the following features that you have discovered, what conclusions can you make about this microorganism? 1. It does not have a cellular structure 2. It cannot exist independently 3. It can be visualized only by an electron microscope 4. It has DNA as its genomic material 5. It does not have a nucleus
Virus
In the following picture, letters X and Y most likely represent
Virus and animal cell, respectively
___________ is the basic unit of a protein (in other words proteins are made from these basic units)
amino acid
Why do bacterial cells regulate gene expression
in response to a changing environment
Which of the following is a change in the sequence of DNA that leads to formation of a stop codon?
nonsense mutation
Which of the following mutation in a DNA sequence will lead to the formation of a stop codon?
nonsense mutation
During fermentation, electrons are transferred from an organic donor compound to
other organic compounds
Which of the following terminologies describe genetic changes that can occur in a bacterial population
transcription
A bacteria has shared antibiotic resistance genes from another bacterium in the environment via plasmids. This is an example of HGT horizontal gene transfer
true
A sequence of 3 nucleotides in the DNA codes for an amino acid
true
Which of the following is true about Eukaryotes? 1. Larger in size than prokaryotes 2. Have internal membranes 3. Contain a nucleus 4. Lack cellular organization
1,2,3
Which of the following can be associated with Archaea? 1. Have a cellular Structure 2. Can be found in extreme environments 3. Lack internal membranes 4. Small in size 5. Classified as prokaryotes
1,2,3,4,& 5
Which of the following can be classified as cellular organisms? 1. Bacteria 2. Viruses 3. Archaea 4. Fungi 5. Prions
1,3,& 4
identify the specific components that make up DNA
A = BASE B = PHOSPHATE C = SUGAR
Which of the following sentences about viruses are correct? A. Viruses are made of DNA or RNA, and proteins B. Viruses are cellular. C. Viruses need host cells for reproduction and survival. D. Viruses contain metabolic pathways E. Viruses can make their own proteins. F. Some viruses may have a lipid envelope
A, C & F
In a cell, the molecule that stores energy to do useful work is -------------
ATP
[------------] , [------------------] and [--------------------] are formed at the end of glycolysis pathway.
ATP, Pyruvate and NADH
Which of the following is NOT a feature of a eukaryotic organism?
Absence of membrane bound organelles
Which of the following best represent organisms with a "Nucleus" in the picture below? Choose all for full credit.
Algae, Fungi
In glucose molecule, high energy electrons are stored within which of the following?
C-H bonds
According to the Central Dogma, which of the following statements represent the flow of genetic information in cells?
DNA to RNA to protein
Listed below in the left column are different structures found in the bacterial cell. Match these bacterial cell structures with their correct function shown in the right column. Each answer may be used one time only.
Endospore: enhances survival in unfavorable conditions Capsule: protects the cell against drying Flagella: responsible for cellular motility or movement Fimbriae: responsible for attachment of cells to surfaces Cell Wall: protects against lysis
Bacteria make structures called --------- to tide over unfavorable conditions in their environment .
Endospores
All viruses contain DNA as the genetic material
False
An antibiotic targeting the the nuclear membrane would be an effective treatment for bacterial infections.
False
It is possible to treat a virus infection with an agent that targets the protein synthesis machinery to inhibit the synthesis of proteins.
False
It would be unsafe to administer an antibiotic that inhibits peptidoglycan synthesis, because this could damage the eukaryotic cell wall in addition to damaging the bacterial cell wall.
False
Only single-celled organisms represent the domain Eukarya.
False
Following terms on the left are associated with protein synthesis and gene regulation. Match these items with their correct definitions on the right. Each answer must be used one time only.
Gene: sequence of bases/DNA that codes for a protein and thus determines a trait Codon: a sequence of three bases/nucleotides that together form a unit of genetic code in a DNA or RNA molecule. Activator: A protein that binds to DNA and stimulates transcription of a specific gene. Repressor: A protein that binds to an operator and physically blocks RNA polymerase from binding to a promoter site
The time taken for one bacterial cell to divide into two cells is called-----------
Generation time
Which of the following is an example of a silent mutation?
Mutation in the DNA that replaces an amino acid with the same amino acid
The following picture depicts sizes in the microbial world. Based on this picture, arrange the following in order from largest to smallest: Bacteria cell, Nerve cell, Chickenpox virus, Sulfur atom, Water molecule
Nerve cell, Bacterial cell, Chickenpox virus, Water molecule, Sulfur atom
Prions is classified under which of the following categories?
Non-living
The bacterial cell wall is made up of which of the following UNIQUE component?
Peptidoglycan
Which of the following is true for a plasmid?
Plasmids are small, circular pieces of double stranded DNA found in bacteria
The binomial system assigns a 2-part name to organisms. In accordance with Binomial nomenclature, what does the underlined part of the name denote in the following example? Escherichia coli
Species
Which of the following is true about horizontal gene transfer?
The transfer of genes from one genome to another through mechanisms such as transposable elements, plasmid exchange, viral activity, and perhaps fusions of different organisms. A process in which an organism incorporates genetic material from another organism without being the offspring of that organism transfer of genes between cells of the same generation
Which of the following is a feature of Archaea?
They can live in extreme environments
In the DNA molecule, adenine (A) pairs with
Thymine (T)
A patient with an ear infection was administered an antibiotic that targets the peptidoglycan layer. The causative agent of the infection is a ------------.
bacteria
Prokaryotes consist of two groups of organisms --------------- & -------------- .
bacteria & archaea
In nature, bacteria grow in communities that are encased in a protective gelatinous covering. Such bacterial communities are called -----------
biofilm
Botulism or food poisoning is caused by Clostridium species. It is difficult to eliminate this bacteria from contaminated food because of formation of ----------.
endospores
Fermentation produces more ATP than Aerobic respiration.
false
The energy generated in anabolic reactions are used up in catabolic reactions,
false
The following picture shows how bacteria grow in numbers through the process of binary fission
false
The genetic code converts the sequence of the amino acids into the sequence of nucleotides
false
Which of the following mutations in a DNA sequence will lead to a change in the reading frame of the DNA sequence?
insertion
In --------- phase of the growth curve, there is no change in the number of bacteria. Pick all of the correct answers for complete credit.
lag stationary
The following picture depicts the series of events that led to the evolution of the modern eukaryotic cell. The engulfment of the aerobic bacterium by the ancestral cell led to the evolution of __________, while the engulfment of the photosynthetic bacterium led to the evolution of ________________
mitochondria, chloroplasts
__________ & _____________ are the two types of regulators that you learned about in this module
repressor and activator
During translation, the codons on the mRNA are read and the respective amino acids are incorporated into the protein. This occurs on the surface of the
ribosome
Viruses are not included in the three domain system of classification because
they are not living organisms.
Viruses are called intracellular obligate organisms because
they require a host cell to replicate within
An anaerobic bacteria does not require oxygen.
true
Bacteria that can form endospores are generally more resistant to treatment and control methods than the bacteria that do not make endospores.
true
Catabolic reactions (that breakdown of complex molecules into simple ones) releases energy that is used in anabolic reactions (building complex molecules from simple ones)
true
During aerobic respiration, the electrons from glucose molecule are transported through a series of reactions to oxygen. The energy of the electrons, that is released in the process, is used to synthesize ATP.
true
During anaerobic respiration, bacteria transport electrons from donors to acceptors other than oxygen.
true
During transcription, only one strand of DNA is used as a template to make the RNA
true
Each organism has an optimum temperature of growth.
true
