Microbiology SP 2026

Question 1

Microbiology SP 2026. The stage of the cell cycle where the cell spends most of its life and performs its normal functions is:

Prophase
Interphase
Mitosis
Cytokinesis

Question 2

A bacterial cell’s genome is located in the:

Nucleus
Nucleoid
Plasmid
Ribosome

Question 3

The process of DNA replication is:

Conservative
Dispersive
Semiconservative
Non-conservative

Question 4

Enzymes that play a role in DNA replication include:

Helicase
DNA polymerase
Ligase
All of these are correct

Question 5

The type of RNA that carries the genetic information from DNA to the ribosome is:

Messenger RNA
Transfer RNA
Ribosomal RNA
Small nuclear RNA

Question 6

The synthesis of an RNA molecule from a DNA template is called:

Translation
Transcription
Replication
Transformation

Question 7

In eukaryotic cells, transcription occurs in the:

Nucleus
Cytoplasm
Ribosome
Mitochondria

Question 8

The triplet of bases on a tRNA molecule that is complementary to an mRNA codon is the:

Codon
Anticodon
Promoter
Intron

Question 9

The nitrogenous base that is found in RNA but not in DNA is: Microbiology SP 2026

Guanine
Adenine
Uracil
Thymine

Question 10

During DNA replication, the new strand is always synthesized in the direction:

5′ to 3′
3′ to 5′
5′ to 5′
3′ to 3′

Question 11

The enzyme responsible for adding new nucleotides to the growing DNA strand is:

Helicase
DNA polymerase
Ligase
RNA polymerase

Question 12

Small fragments of DNA produced on the lagging strand during replication are:

Okazaki fragments
RNA primers
Leading strands
Introns

Question 13

A segment of DNA that codes for a functional product, such as a protein, is a:

Operon
Exon
Gene
Chromosome

Question 14

The observable physical characteristics of an organism are its:

Phenotype
Genotype
Haplotype
Allele

Question 15

The division of the nucleus in somatic cells is called:

Binary fission
Mitosis
Meiosis
Budding

Question 16

The phase of mitosis where sister chromatids separate and move toward opposite poles is:

Prophase
Metaphase
Anaphase
Telophase

Question 17

A normal human diploid cell contains how many chromosomes?

Question 18

A change in the nucleotide sequence of DNA is a:

Mutation
Adaptation
Selection
Evolution

Question 19

A mutation that involves the insertion or deletion of one or more nucleotides, shifting the reading frame, is a:

Point mutation
Frameshift mutation
Silent mutation
Missense mutation

Question 20

In aerobic respiration, the final electron acceptor is:

CO2
Oxygen
Nitrogen
Methane

Question 21

The process of converting the information in mRNA into a protein is:

Translation
Transcription
Replication
Translocation

Question 22

The site of protein synthesis in the cell is the: Microbiology SP 2026

Nucleus
Ribosome
Lysosome
Golgi apparatu

Question 23

Which of the following is TRUE with regard to plasmids?

It is a circular DNA molecule.
It is an extra-chromosomal DNA molecule.
It may carry virulence genes.
It is often involved in horizontal gene transfer.
All of these are true

Question 24

If electrons are removed from a compound X and transferred to another compound Y, then:

X is reduced and Y is oxidized
X is oxidized and Y is reduced
Both X and Y are oxidized
Both X and Y are reduced

Question 25

EXTRA CREDIT: What is the total maximum yield of ATP from 1 molecule of glucose by the complete process of aerobic respiration?

38 ATP (theoretical maximum in prokaryotes)

Question 26

The RNA molecule that carries the amino acids to the ribosomes during protein synthesis is called:

Ribosomal RNA
Messenger RNA
Transfer RNA
All of the above

Question 27

Which of these organisms does not produce any Reactive Oxygen Species (ROS)?

Question 28

All mutagens are carcinogens.

True
False

Question 29

Which term best describes the DNA in chloroplasts and mitochondria?

Genomic
Chromosomal
Extrachromosomal
Plasmid

Question 30

Name the continuously synthesized daughter strand labeled 4.

Leading strand

Question 31

Which of the following correctly explains why DNA replication is described as semiconservative?

Each daughter strand contains one old parental strand and one new strand.
One daughter strand is exactly like the parent and the other is newly synthesized.
Both daughter strands are newly synthesized and the parent DNA is degraded.
Both daughter strands contain only newly synthesized DNA.

Question 32

Which of these organisms will only grow in the presence of a low and specific concentration of $O_2$?

Question 33

If the codon for amino acid alanine is $5’$-GCA-$3’$ then the anticodon is:

$5’$-CGU-$3’$
$3’$-GCA-$5’$
$3’$-CGU-$5’$
$5’$-UGC-$3’$

Question 34

Reactive Oxygen Species (ROS) are degraded by several enzymes (Catalase, Peroxidases etc.), none of which are produced by:

Obligate aerobes
Facultative anaerobes
Obligate anaerobes
Microaerophiles

Question 35

If a microorganism were isolated from the human gut, it would likely be classified as (select ALL that apply):

A facultative anaerobe.
A mesophile.
An acidophile
A psychrophile.

Question 36

Staphylococcus aureus is a common human pathogen that can survive high levels of sweat on the skin. Based on this entire information you would classify it as (Choose ALL that apply):

Mesophile
Halotolerant
Psychrophile
Acidophile

Question 37

Helicobacter pylori… is able to survive in the high acid conditions of the stomach… because:

it is an acidophile
it produces urease
it produces catalase
it is halotolerant

Question 38

Name the component marked 6 which puts down a short sequence of RNA so that DNA synthesis can occur.

Primase

Question 39

During which of the phases of aerobic respiration is the majority of ATP formed?

Glycolysis
Krebs cycle
Electron Transport Chain
Bridge reaction Microbiology SP 2026

Question 40

Which of these organisms prefers to grow in $O_2$ rich conditions, but can also survive in $O_2$ poor conditions?

Question 41

UV light causes which of the following?

Formation of thymine dimers
Ss (single-strand) or ds (double-strand) breaks in DNA backbone
None of the above
Complementary base pairing
Structurally similar nucleotide analogs to be inserted

Question 42

What type of mutation is this? (Original: $5’$-AUG-CCG… Mutated: $5’$-AUG-CGG…)

Nonsense mutation
Frameshift mutation
Silent mutation
Missense mutation
Back mutation

Question 43

All of the following are true of Glycolysis except:

Occurs without oxygen
Occurs during fermentation
Involves the reduction of an electron carrier
Degrades glucose to $CO_2$ and $H_2O$
Ends with formation of pyruvate

Question 44

EXTRA CREDIT: A strict anaerobe is known to be the causative organism of Gas Gangrene. Name a line of therapy that is used to treat this infection by this specific organism based on its aerotolerance OR name the organism.

Hyperbaric oxygen therapy (OR Clostridium perfringens)

Question 45

Plants would fall under which of these classifications?

Photosynthetic microbes
Chemoautotrophs
Photoheterotrophs
Photoautotrophs
Chemoheterotrophs

Question 46

What is enzyme 3 shown in the schematic and what is region 1 on the operon DNA that it binds to?

Enzyme 3: RNA Polymerase; Region 1: Promoter

Question 47

The three-base sequence on a/an ___ that codes for an amino acid is called a(n) ___.

tRNA; codon
Exon; anticodon
mRNA; codon
DNA; codon
mRNA; anticodon Microbiology SP 2026

Question 48

The anti-parallel arrangement within the DNA molecule refers to:

Each base bonding at the 1′ position of the sugar
One helix strand that runs 5′ to 3′ and the complementary strand runs 3′ to 5′
An original parent DNA strand and the one newly synthesized DNA strand make up the new DNA molecule formed during replication
A purine always bonding to a pyrimidine
The genes on the DNA can be oriented in either direction

Question 49

Cells with the exact same genotype will always express the exact same phenotype.

True
False

Question 50

Name the component marked 10 that replaces the RNA sequences with DNA in the newly formed daughter strand.

DNA Polymerase I

Question 51

2 ATP is made during the Transition or Bridge reaction of aerobic respiration.

True
False

Question 52

Which of the following is an example of an organism’s genotype?

It’s behavioral response to certain conditions
Which enzymes are being synthesized by it
The micro-environment to which it belongs
All the genes in it’s genome
The organism’s observable characteristics

Question 53

Use the chart below to figure out the sequence of amino acids that make up the final peptide chain from this mRNA sequence: $5’$-AUG-GUC-CGA-UGU-CCC-CAA-UGA-UGC-CGG-UGG-UAA-$3’$

Arg-Cys-Met-Cys-Pro-Arg-Trp
Met-Cys-Pro-Arg-Val-Gln-Cys-Arg-Trp
Met-Arg-Cys-Pro-Gln-Cys-Arg
Met-Val-Arg-Cys-Pro-Gln-Cys-Arg-Trp
Met-Val-Arg-Cys-Pro-Gln

Note: The sequence ends at “Gln” because the following codon, UGA, is a stop codon.

Question 54

Which is a common electron acceptor in catabolic reactions? Microbiology SP 2026

ATP
ADP
NAD+
FADH2
NADPH

Microbiology, Microbiology Exam, Microbiology SP 2026

Isaura K

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