Micro Final Exam

Digestive tract microbiome plays no role in maintaining a person's health.

False

Archaea are very similar to bacteria and have rigid cell walls made of peptidoglycan.

false

Which of the following about the Golden Age of Medical Microbiology is FALSE?

It started with the development of the first microscopes.

If Pasteur had done his experiments investigating spontaneous generation in a horse stable,

the results would probably have supported the idea of spontaneous generation.

Which of the following bacterial pairs is LEAST related?

Streptococcus pneumoniae AND Mycoplasma pneumoniae

Which of the following statements about newly emerging or reemerging diseases is FALSE?

They are all caused by drug-resistant pathogens.

Which of these scientists were involved in investigating the idea of spontaneous generation?

Redi and Pasteur

Which of the statements regarding smallpox is TRUE?

Smallpox has been eliminated as a naturally occurring infection in human beings through vaccination.

The human body only contains bacteria during illness.

false

Identify three factors that cause certain infectious diseases to become more common.

-Reduction of vaccination against certain diseases such as measles.

-Diseases under control by antimicrobial medications become resistant to the medications.

-The aging population is more susceptible to infectious diseases.

Bacteria are good research models because they

share many properties with more complex organisms

Cellulose is a major component of plants and is only directly digested by

microorganisms.

The Earth BioGenome Project aims to

determine the DNA sequence of all known animal, plant, protozoan, and fungal species.

The system by which organisms are named is referred to as

nomenclature

Identify two features that distinguish prokaryotic cells form eukaryotic cells.

-Eukaryotic cells have membrane-bound orgnelles while prokaryotic cells do not.

-Eukaryotic cells have a nucleus while prokaryotic cells do not.

What was important about the shape of the flasks used by Pasteur in his experiments proving biogenesis?

The swan neck of the flasks allowed "vital force" to enter them but prevented bacteria from falling into the broth.

A new organism was found that was unicellular and 1 cm long. The "large" size of this organism alone would

not be useful for identifying it.

The work of Tyndall and Cohn

explained why some spontaneous generation investigators got different results from those of Pasteur.

The contradictory results obtained by different scientists apparently doing the same experiments in investigating spontaneous generation

show the importance of exactly duplicating experimental conditions.

The cell types that lack a membrane-bound nucleus and have rigid cell walls of peptidoglycan are

bacteria

The word "animalcule" was first used by_________.

van Leeuwenhoek

The idea of spontaneous generation postulated that

living organisms could spontaneously arise from non-living material.

Consider the Venn diagram pertaining to the three domains, and select the CORRECT characterization. Remember that characteristics shared by two or more items are found in the circle overlaps.

Eukaryote AND multicellular - G

An illness outbreak occurs in New York City birds in the late 1990s. After an investigation, the Centers for Disease Control (CDC) determine that the agent causing the is the West Nile virus. Outbreaks of this illness have been observed in several other countries in Asia and the Middle East across the last 50 years, but not in the United States. With this information, what would be the best categorization of this infectious agent/disease?

This is an emerging infection. It hasn't been around that long, and it has made a jump across continents into a new susceptible population.

Which are the correctly written scientific name?

Staphylococcus aureus

When the pH of a solution changes from 9 to 2, the H+ concentration

increases as the solution becomes more acidic.

When sugar is dissolved in a cup of water, the water is

The solvent

The atomic number for an atom of a specific element is equal to

the number of protons in a single atom of that element.

The most important feature of a protein is its

shape

Alpha helices and beta-pleated sheets form a protein's

secondary structure.

Amino acids in proteins are linked to one another by peptide bonds between the

carboxyl group of one amino acid and the amino group of another.

Side chains are important to proteins because they

help determine protein shape AND help determine the solubility of the protein in water.

Microorganisms use hydrogen bonds to attach themselves to the surfaces that they live on. Many of them lose hold of the surface because of the weak nature of these bonds and end up dying or being washed away. Why don't microbes just use covalent bonds instead?

Covalent bonds typically require enzymes to form/break, whereas hydrogen bonds don't. If covalent bonds were used, it would require much more energy and molecules to be contributed from the cell. Hydrogen bonds don't have these requirements.

Which is the uncharged component of the atom?

neutron

Which statement regarding water is TRUE?

-Water is referred to as a universal solvent.

-Water is a polar molecule.

-Water makes up over 70% of an organism.

-Water is often a product or reactant in chemical reactions.

All of the answer choices are correct.

Which of the following are found in RNA but not in DNA?

Ribose AND uracil

Which of the statements about ions is TRUE?

Anions are negatively charged atoms while cations are positively charged atoms.

Which of these bonds are weak individually but are much stronger as a group?

Ionic AND hydrogen

Which base pairing example is INCORRECT

G:T

Weak bonds are important for the_________ structure of proteins.

secondary, tertiary, AND quaternary

How many different amino acids are there to choose from when assembling a protein?

20

Dehydration synthesis is involved in the synthesis of all of the following EXCEPT

glucose

Simple lipids contain carbon, hydrogen, and oxygen in a 1:2:1 ratio.

False

In addition to investigations with bacteria that led to Pasteur being considered the Father of Microbiology, he also

found that some molecules can exist as stereoisomers AND separated organic acids using a microscope.

What determines the chemical and physical properties of an atom of an element?

atomic number

The subunits (building blocks) of proteins are

amino acids

Please identify the CORRECT definition.

Electrolytes are salts that conduct electricity when they are dissolved in water.

The negatively charged component of the atom is the

electron

The N terminal in a protein is

the end characterized by a free amino group.

Select the FALSE statement regarding carbohydrates.

Cholesterol and ergosterol are examples of carbohydrates.

Consider the Venn diagram pertaining to prokaryotes, eukaryotes and acellular agents, and select the INCORRECT classification. Remember that in a Venn diagram, common characterisitcs are found in the circle overlaps.

80S ribosomes, cytoplasm and nucleic acid - E

Select the TRUE statement(s) regarding eukaryotes.

Eukaryotes have a more complex internal structure than archaea or bacteria AND have a membrane around the DNA.

Thiomargarita namibiensis can not be a eukaryote because it is only 1 mm in width.

False

Outside of a host cell, viruses are

inert, and not capable of replication

Bacteria and eukarya both contain membrane-bound organelles.

false

Microorganisms are useful for all of the following EXCEPT

causing disease

Select the statement that is TRUE regarding viroids.

They are naked (lacking a protein shell) pieces of RNA.

A viral particle consists of DNA, RNA, and protein.

False

Microorganisms are involved in all of the following EXCEPT

There are no exceptions here. There are microorganisms that participate in each of these activities.

Scientists recently cloned Louis Pasteur and put him to work in a modern lab. He immediately developed a topical gel (used externally) that breaks down proteins. Since he hasn't been around for some time, he's unsure what the best application for his invention might be. Help him out. What pathogenic agent would this gel be most effective and safe at eliminating?

viruses on the surface of the skin

A microbiologist obtained two pure isolated biological samples: one is a virus, and one is a viroid. The labels came off the samples during a move from one lab to the next, however. The scientist felt she could distinguish between the two samples by analyzing for the presence of a single type of molecule. What would she be looking for to differentiate between the two?

Protein

The structures present in the hay infusions used in experiments on spontaneous generation that made them difficult to sterilize are _________.

Endospores

Viruses may only be grown

in living cells

Which is usually NOT true of archaea?

They reproduce by mitosis.

Viruses are in the domain(s)

-eukarya.

-viridae.

-archaea AND bacteria.

-bacteria AND viridae.

None of the answer choices is correct.

Which of the following are classes of macromolecules?

- Lipids

- Nucleic Acids

-Carbohydrates

-Proteins

Identify the type of reaction illustrated by the following:

XY + Z ---> XZ + Y

Exchange

The mass number of an atom is equal to

the number of neutrons and protons.

How many carbon atoms do the sugars found in nucleic acids contain?

5 carbon atoms

D-amino acids are associated with

bacterial cell walls

The most important molecule(s) in the world is (are)_________.

water

If electrons are shared unequally, a(n)_________ bond is formed.

polar

Structural isomers

contain the same number of atoms/elements, but in different arrangements AND are exemplified by glucose and galactose.

Amino acids that contain many methyl (-CH3) groups

are nonpolar

Which statements about proteins are TRUE?

They are involved in almost every important function performed by a cell AND make up more than 50% of the dry weight of a cell.

Charged atoms are called

ions

Enzymes are required to break which of the following bonds?

Covalent

To which end of the nucleic acid chain are more nucleotides added during DNA synthesis?

3 prime (3') end

Which of the following best describes the structure of DNA?

A double helix consisting of antiparallel two sugar-phosphate backbones with nucleobases oriented towards the interior.

Which of the following correctly describes the pairing and hydrogen bonding of nucleobases in DNA?

Adenine pairs with thymine via two hydrogen bonds; cytosine pairs with guanine via three hydrogen bonds.

Select the CORRECT statement regarding saturated fats and unsaturated fats.

Unsaturated fats have a lower melting temperature than saturated fats.

Unsaturated fats have lower melting points than saturated fats.

True

DNA is always double-stranded, but RNA is always single-stranded.

False

The components of fats are fatty acids and

Glycerol

Select the CORRECT statement regarding carbohydrates.

They may interconvert between ring and linear structures.

Which if the following is TRUE regarding viruses?

They are obligate intracellular parasites.

Plants are dependent on microorganisms for

changing atmospheric nitrogen to a usable form.

Which group(s) below contain single-celled and multicellular organisms?

Algae AND fungi

Which of the following would Antonie van Leeuwenhoek not have observed?

Human immunodeficiency virus

Bacteria are useful to study because

they have the same fundamental metabolic and genetic properties as higher organisms.

A scientist discovers a new species near coral reefs in Australia. He finds that this single-celled species is photosynthetic (using sunlight for energy), has a rigid cell wall structure with no peptidoglycan, uses a flagellum for motion, and contains a variety of internal structures that are membrane-bound. Given this information, this new species is most likely a(n) _________ cell in the _________ domain.

algal; Eukarya

Smallpox

has not occurred anywhere in the word since 1977

Viroids are naked (lacking a protein shell) pieces of RNA that infect plants.

True

Identify which three of the following Antonie van Leeuwenhoek would not have observed.

-Smallpox virus

-SARS-CoV-2

-Prions

Ulcers, previously thought to be caused by stress, are in fact often caused by

a bacterial infection

Viruses and bacteria are both unicellular.

False

An extreme environment in which archaea have been found is

boiling hot springs

The scientific name of an organism indicates its domain.

False

All living organisms

may be classified in three domains.

The outbreak of measles within the last few years is due to

a decline in vaccination of children in the previous years.