Micro Lecture CH 1-5 Exam 1 2023
The first cells appeared about ______ billion years ago.
3.8
The size of a eukaryotic cell ribosome is ______.
80S
The Dutch merchant who made and used quality magnifying lenses to see and record microorganisms was _____.
Antonie van Leeuwenhoek
What three components comprise the flagellum, extending from the cytoplasm to the exterior of the cell?
Basal body, hook, filament
Which structure protects bacteria from being phagocytized by white blood cells?
Capsule
Which organelle is found in algae but not found in protozoa or fungi?
Chloroplast
Which order below reflects the correct procedure for Gram staining?
Crystal violet-iodine-alcohol/acetone-safranin
Viral nucleic acids include which of the following?
Double-stranded DNA Single-stranded DNA Double-stranded RNA Single-stranded RNA
Which of the following is not associated with every virus?
Envelope
An organelle that is a stack of flattened, membranous sacs and functions to receive, modify, and package proteins for cell secretion is the ________.
Golgi apparatus
Which of the following is a type of cytopathic effect?
Inclusions in the nucleus Multinucleated giant cells Inclusions in the cytoplasm Cells change shape
Which of the following is not a characteristic of bacteria?
Its DNA is wrapped around histones.
The surgeon who advocated using disinfectants on hands and in the air prior to surgery was _____.
Joseph Lister
Which of the following is a unique characteristic of viruses that distinguishes them from the other major groups of microorganisms?
Lack cell structure
Which of the following is not a human use of microorganisms?
Manufacturing copper wire
Which of the following is not considered a microorganism?
Mosquito
Which of the following is not a function of the eukaryote glycocalyx?
Movement
Who developed a rabies vaccine by separating bacteria from virus using a filter?
Pasteur
Which scientist showed that anthrax was caused by the bacterium, Bacillus anthracis?
Robert Koch
Which scientific field is involved in the identification, classification, and naming of organisms?
Taxonomy
Which of the following is not a typical capsid shape?
Tetrahedral
Which group of microorganisms is composed only of hereditary material wrapped in a protein covering?
Viruses
Which organelle contains cristae where enzymes and electron carriers for aerobic respiration are found?
Which organelle contains cristae where enzymes and electron carriers for aerobic respiration are found?
The _____ stain is used to stain and differentiate Mycobacterium and Nocardia from other bacteria.
acid-fast
Protists include ______.
algae and protozoa
The term that refers to flagella at both poles is _______.
amphitrichous
All of the following pertain to virus envelopes except ________.
are located between the capsid and nucleic acid
All microorganisms are best defined as organisms that ______.
are too small to be seen with the unaided eye
The two functions of bacterial appendages are ________.
attachment and motility
A flagellum is anchored into the bacterial cell envelope by its _______.
basal body
Using microbes to detoxify a site contaminated with heavy metals is an example of _____.
bioremediation
Viruses ________.
cannot be seen in a light microscope
A(n) _______ is the protein shell around the nucleic acid core of a virus.
capsid
Helical and icosahedral are terms used to describe the shapes of a virus ______.
capsid
Virus capsids are made from subunits called ______.
capsomeres
Peptidoglycan is a unique macromolecule found in bacterial _______.
cell walls
When a eukaryotic cell is not undergoing mitosis, the DNA and its associated proteins appear as a visible network of dark fibers called the _____.
chromatin
Bacterial cells could have any of the following appendages except _______.
cilia
Taxonomy does not involve _____.
common name
The microorganisms that recycle nutrients by breaking down dead matter and wastes are called _____.
decomposers
The core of every virus particle always contains _____.
either DNA or RNA
The cell's series of tunnel-like membranes functioning in transport and storage are the _______.
endoplasmic reticulum
The cell _______ can be composed of three layers: the cytoplasmic membrane, the cell wall, and the outer membrane.
envelope
The short, numerous appendages used by some bacterial cells for adhering to surfaces are called _______.
fimbriae
Chitin is a chemical component of the cell walls of ______.
fungi
When humans manipulate the genes of microorganisms, the process is called _____.
genetic engineering
During the Gram stain, ______ cells decolorize when the alcohol is applied.
gram-negative
A bacterial cell wall that has primarily peptidoglycan with small amounts of teichoic acid and lipoteichoic acid is _______.
gram-positive
Sterility refers to ______.
having an absence of any life forms and viral particles
Viruses attach to their hosts via ________.
host glycoproteins
Host cells of viruses include ________.
humans and other animals plants and fungi bacteria protozoa and algae
One of the principal capsid shapes is a 20-sided figure with 12 evenly spaced corners referred to as a(n) _______ capsid.
icosahedral
The term that refers to the presence of a tuft of flagella emerging from the same site is _______.
lophotrichous
A(n) _______ originates from the Golgi apparatus as one type of vesicle that contains a variety of enzymes for intracellular digestion.
lysosome
Viruses have all the following except ________.
metabolism
Living things ordinarily too small to be seen with the unaided eye are termed _____.
microorganisms
There are nine peripheral pairs and one central pair of _______ found inside eukaryotic flagella and cilia.
microtubules
The eukaryotic cell's glycocalyx is ________.
mostly polysaccharide
Chemotaxis refers to the ability to ________.
move in response to a chemical
A naked virus has only a(n) _____.
nucleocapsid
The site for ribosomal RNA synthesis is the ______.
nucleolus
In general, most DNA viruses multiply in the host cell's _______, while most RNA viruses multiply in the host cell's _______.
nucleus; cytoplasm
Helminths are _____.
parasitic worms
Disease-causing microorganisms are called _____.
pathogens
The term that refers to the presence of flagella over the cell surface is _______.
peritrichous
The passageways in the nuclear envelope for movement of substances to and from the nucleus and cytoplasm are called nuclear ________.
pores
Movement of a cell toward a chemical stimulus is termed _______.
positive chemotaxis
Cells, like bacteria and archaea, that do not have a nucleus in their cells have traditionally been called _____.
prokaryotes
Histones are ________.
proteins associated with DNA in the nucleus
Cell walls are not usually found in _____.
protozoa
Cilia are structures for motility found primarily in _____.
protozoa
Viral spikes ________.
protrude from the envelope
Viruses acquire envelopes around their nucleocapsids during _____.
release
The most prevalent worldwide infectious diseases are _____.
respiratory diseases
The transfer of genes during bacterial conjugation involves rigid, tubular appendages called _______.
sex pili
The eukaryote cell membrane is composed of ______.
sterols proteins phospholipids cholesterol
The first primitive eukaryotic cells likely evolved from ______.
the last common ancestor
Host range is limited by ________.
type of host cell receptors on cell membrane
Protists with contractile vacuoles ________.
use them to expel excess water from the cell
The outcome of the Gram stain is based on differences in the cell's _______.
wall
