Exam 1 Flashcards
True/False. Prokaryotic cells are animal cells and Eukaryotic cells and bacterial cells.
False. Prokayotic = Bacterial and Eukaryotic = Animal
What are the four things that both prokaryotic cells and eukaryotic cells have in common?
- Cell membrane
- Cytoplasm
- DNA
- Ribosomes
True/False. Prokayotic cells don’t have a nucleus or membrane-enclosed organelles and Eukaryotic cells do.
True.
What are the three main groups of the cytoplasm?
- Macromolecules: proteins, mRNA and tRNA
- Small molecules: energy sources, precursors of macromolecules, metabolites or vitamins
- Various inorganic ions required for enzymatic activity
What is the role of the cytoplasm?
Helps to facilitate chemical reactions and dissolve solutes, and it contains the nucleoid and ribosomes
Which of the following are found within the nucleoid?
a. DNA
b. RNA
c. Proteins
d. All the above
d. All the above
The ____ is a complete set of DNA including all essential genes.
Bacterial genome
What proteins compact the nucleoid?
- Nucleoid Associated proteins bound to DNA
- Supercoiling by DNA gyrase and topoisomerase I
What is a base pair?
One pair of nucleotide bases that connect the complementary strands of DNA
Which of the following is false in regards to a plasmid?
a. Circular molecule of DNA that replicates separately from the chromosome
b. Not part of the nucleoid
c. Essential under normal conditions
d. Each plasmid has a defined copy number regulated by the plasmid
c. Essential under normal conditions
- Its NOT essential under normal conditions
What is important about plasmids?
They often contain genes associated with causing disease (virulence factors) or to survive in presence of antibiotics and other toxic compounds (resistance genes)
What is a conjugative plasmid?
When plasmids can transfer cell to cell
What is found within the bacterial envelope?
- Cytoplasmic Membrane
- Cell wall (peptidoglycan layer)
- Periplasmic Space
- Outer membrane (gram-negative bacteria)
- Capsule (some bacteria)
- Envelope associated: Pili/Fimbriae, flagella, secretion systems
What are the functions of the bacterial envelope?
- Protects cell from environment or host
- Packages internal components
- Provides structural rigidity
- Produces energy
- Facilitates uptake of nutrients and efflux of toxic substances
What can only some envelope associated components do?
- Enable adhesion to surface or motility
- Provide resistance to some antibiotics or detergents
- Enable bacterial mating (conjugation)
____ bacteria have a thin layer of peptidoglycan in the periplasmic space while ___ bacteria have a thick layer of peptidoglycan.
Gram- negative, Gram-positive
Which bacteria contains teichoic acids attached to the peptidoglycan and which have lipopolysaccharides in the outer membrane?
Gram-positive have Teichoic
Gram-negative have LPS
The cytoplasmic membrane is composed of ____ and ____.
phospholipid bilayer and proteins
Which part of the phospholipid bilayer is attracted to water and which is not attracted to water?
head “loves” water (hydrophilic)
tail “fears” water (hydrophobic)
True/False. Only hydrophilic compounds can enter the cell by passive diffusion across the bilayer.
False. Only HYDROPHOBIC
What proteins are located within the cytoplasmic membrane?
- Transport proteins
- Energy generating and Electron transport chain components: require ATP synthase
- Proteins that function as anchors or help assemble external structures
The cytoplasmic membrane functions as a _____ barrier, where transport proteins mediate passage of hydrophilic substances in and out of cell
Selective permeability barrier
Which of the following allows for small hydrophilic molecules to passively enter the cell?
a. Transporter proteins
b. Porin proteins
c. Aquaporins
d. All the above
b. Porin proteins
What is the importance of the capsule?
- Help bacteria evade immune system by preventing engulfment
- Aids in attachment to some surfaces
- Increased tolerance to antimicrobial agents
____ is a surface component involved in bacterial conjugation.
Sex pilus
Which of the following are considered surface projections?
a. Flagella
b. Pili/Fimbriae
c. Secretion Systems
d. All the above
d. All the above
When ___ enters a host, it can revert to its active state, multiply, and cause disease.
Endospore
What is able to live in extreme conditions?
Extremophiles
True/False. An obligate symbiont cannot live without a host and facultative symbionts live together but they can live without a host as well.
True
____ can be carried but it doesn’t always cause harm, unless under certain conditions like stress.
Facultative pathogenic
True/False. Eukarytoes replicate through binary fission and Prokayotes replicate through mitosis.
False. Prokayotes = binary fission and Eukaryoties = Mitosis
True/False. Genus is capital and italic, Species and Subspecies are italic, and Serovar is not italic but its capital.
True.
What is the definition of Commensalism?
Good for one, no problem for the other
____ are necessary and the relation is positive for both while ____ takes advantage of the other.
Mutualism, Parasitism
True/False. Flagella is mainly found within gram-negative bacteria.
True
What are the virulence factors of a capsule?
- Colonization
- Invasion
- Adhesion
- Protection against: phagocytosis, and complement
_____ antigen is a capsular antigen.
K-antigen
Which of the following is true regarding exotoxins?
a. Bacterial metabolites
b. Proteins with high molecular weight
c. Types I, II, III
d. All the above are true
d. All the above are true
What are type I exotoxins?
- Bind receptor
- Disturb cell metabolism
Type ___ exotoxins damage the cell wall and type ___ are intracellular toxins with an A and B component.
II, III
What are the two components of Type III exotoxins?
A component: goes IC
B (binding) component: binds to membrane
Which of the following is true regarding gram negative endotoxins?
a. Cell wall components
b. Cause a lot of damage
c. Cause immune reactions
d. All the above
d. All the above
True/False. Gram negative endotoxins have an LPS that is stable to heat, and can cause cardiovascular shock.
True
What is the function of LPS?
Protect against: toxic products, role in complement
Act as endotoxin
Toxins cell wall Gram-positive
Lipoteichoid acid (LTA) Lipoarabinomannan (Mycobacteria) (LAM) Peptidoglygan
What are obligate aerobes?
Need oxygen to grow and will be found more concentrated on the top of the tube.
What are facultative anaerobes?
Grow better with oxygen but they can also grow without it.
____ is a uniform growth throughout the tube and they don’t use oxygen but it won’t hurt them if they have it around whereas _____ only grow in the absence of oxygen.
Aerotolerant anaerobes, Obligate anaerobes
What is the traditional approach of herd health management?
Treating sick animals, mainly medical management and less preventative
What is the new herd health management approach used today?
Optimize health, welfare and production in a population of animals
What is the definition of latent period?
Latent period: microbe is replicating but not yet enough for the host to become infectious
What is incubation period?
Incubation: Microbe is replicating but not symptomatic yet
What are the three different types of Helminths?
Nematode- roundworm
Cestode - tapeworm
Trematode - fluke
What are arthropods (entomology)?
arachnids and insets; ectoparasites
____ lives on the host and causes infestation where ___ lives inside the host and causes infection.
Ectoparasite, Endoparasite
What is a definitive host?
Harbors adult or sexual stage of the parasite
An ____ host harbors larval or asexual stage of the parasite.
Intermediate host
What is an incidental host?
Unusual host unnecessary for the maintenance of the parasite in nature.
What is acquired immunity?
Conferred by a host’s specific immunity response developed as a result of a previous parasitic infection
True/False. Parasites don’t have a specificity for a particular definitive and intermediate host.
False. They have a specificity and the life cycle can sometimes only be completed within the host
What are common routes of parasite entry?
Ingestion Skin or mucosal penetration Transplacental (prenatal) Transmammary (milk) Arthropod bite (vector) Sexual contact
True/False. Helminths multiply within the host and Protozoa do not multiply within the definitive post.
False. Protozoa multiply in host, Helminths do not multiply in definitive host
What are the different ways parasites can cause mechanical tissue damage?
- Blockage of internal organs
- Pressure atrophy
- Migration through tissues
What are toxic parasite products?
- Destructive enzymes
- Endotoxins
- Toxic secretions
Which of the following is true about the loss of nutrients caused by parasites?
a. Competition with host for nutrients causing a loss of nutrients
b. Interference with nutrient absorption
c. Iron loss
d. All the above are true
d. All the above are true
____ response functions in normal host without prior exposure to invading microbes and ____ consist of antibody response and lymphocyte mediate responses.
Innate, Adaptive response
T/F. Innate response have immunological memory.
False. Adaptive generate immunological memory
Which cell types are involved in the defense against microbes?
Phagocytic
Lymphocytes: B and T cells, Large granular lymphocytes
What does the phagosome fuse with in phagocytosis?
Lysosome
Innate immune system characteristics
- Pattern recognition receptors (TLR, RLR, complement)
- Missing/ altered self receptors (NK cells)
What are characteristics of adaptive immune system?
- Antigen presentation (MHC)
- Antibodies
- T cell receptors
What is the function of neutrophils?
-Function to phagocytize and kill extracellular bacteria and yeasts pathogens in acute inflammation
What cleans up dead neutrophils?
Macrophages
Which cells are an important defense against helminths and increase with type I hypersensitivities?
Eosinophils
Which cells increase rapidly in number after viral infection and release perforins and granzymes to kill cells?
NK cells
Virus infection-associated ligand are ___ and MHC I molecules are ____.
activating, blocking
True/False. Phagocytic cells use pattern recognition receptors for pathogen recognition.
True
What is a parasite?
Smaller organism that lives on or in and at the expense of a larger organism called the host
What are the three main classes of parasites that can cause disease in humans?
- Helminths
- Ectoparasites
- Protozoa
Which of the following is a cyst in the brain that causes epilepsy, blindness, madness, and death?
a. Taenia solium
b. Toxoplasma gondii
c. Toxocara canis
d. Neurocysticercosis
d. Neurocysticercosis
What are the three diagnostic methods?
Host Species
Site of Infection
Size of parasite
What is the Phylum and Class of a Roundworm?
Phylum Nemathelminthes
Class Nematoda
What are the two Classes of Phylum Platyhelminthes?
Class Cestoda (tapeworms) Class Trematoda (flukes)
Which parasite is elongate/cylindrical in shape, has an alimentary canal, separate sexes, and is free-living?
Nematodes
What are the characteristics of Cestodes?
- Flat body and no alimentary canal
- Scolex
- Stroblia (body) with progottids
- Hermaphroditic
- Indirect life cycle
____ are dorso-ventrally flattened, leaf-like, and have oral and ventral suckers.
Trematodes (flukes)
Which Arthropods are considered Insects?
- Flies
- Fleas
- Lice
- Hemiptera
Which Arthropods are labeled as arachnids?
- Ticks
- Mites
True/False. Adult insets have four pairs of legs, a head, thorax and abdomen section, and antenna.
False. They have THREE pairs of legs
How many pairs of legs do nymph and adult arachnids have compared to larvae?
Nymphs and adults = 4 pairs of legs
Larvae = 3 pairs of legs
What are the unique characteristics of an arachnid body?
Cephalo-thorax and abdomen
No antennae, but palps
____ are unicellular, eukaryotic animals that move via flagella, pseudopodia, gliding movements, and cilia.
Protozoa
