Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

PCOA > Microbiology/ Immunology > Flashcards

Microbiology/ Immunology Flashcards

(96 cards)

Start Studying
1
Q

Prokaryotes that may cause infection

A

Bacteria, rickettsia, and chlamydia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Infectious diseases of the resp tract are most commonly caused by

A

Viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What infection causes more deaths per year than any other bacterial cause?

A

M. tuberculosis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

The majority of skin and soft tissue infections are caused by

A

Normal skin flora- staphylococcal and streptococcal species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Prokaryotes

A

Organisms lacking a nucleus and organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cell walls

A

Generally present in prokaryotes and may be present in eukaryotes. Cell walls protect the microorganism, thus enhancing its survival as well as determining the shape of the micoorganism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Viruses

A

Extremely small microbes that are essentially fragments of nucleic acid packaged in a protein shell
Viruses are not living organisms
Their viral nucleic acid is either DNA or RNA, but not both.
Sole activity is replication which can only take place in living cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Bacilli

A

Bacteria rods, may be single or form long chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Cocci

A

Bacteria spheres, may exist in pairs (diplococci), chains (streptococci), or clusters (staphylococc i)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Spirochettes

A

Curved/spiral bacteria

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Flagella

A

Tail like feature that bacteria may possess for motion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Pili

A

Hair-like structure on bacteria for attachment to host cell surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Plasmids

A

Small circular molecules of DNA that can replicate independent of the chromosomal DNA. Plasmids have implications relative to conveying resistanceto other bacterial strains through the transfer of genetic information.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Spores

A

Some bacteria may produce spores that are highly resistant to environmental changes
Notable spore producing bacteria are Clostridium and Bacillus species

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Capsule

A

May surround bacteria and make it less susceptible to destruction by host organism defenses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Mycoplasmas

A

The smallest, free-living microbes
They lack the bilayered cytoplasmic membrane found in other bacteria, but do not need a host for replication (distinguishes them from viruses)
Do not have cell wall but are bounded by a limiting lipid membrane
Resistant to acid-staining techniques
Obligate intracellular parasites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Unlike other prokaryotes, rickettsiae ad chlamydia require hosts for

A

metabolic and reproductive activities

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Growth curve of bacteria

A

4 phase
Lag phase- bacteria adapt to their new environment
Logarithmic phase- bacteria double during each reproductive period involving chromosomal duplication and binary fission. Period where symptoms begin to appear. The host is most susceptible to abx at this stage
Stationary phase- reproduction and death rates stabilize.
Decline phase- exponential decline in bacterial numbers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Viral replication cycle

A

Attachment and penetration followed by biosynthesis, maturation, and release

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Lysogeny

A

When a virus integrates into the host cells DNA rendering them immune to normal host cell defenses.
May establish a latent or dormant stage of the virus within cells that can later reactivate the virus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Fungi groups

A

Yeast and molds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Hyphae

A

Long chains of intertwined filaments of fungi.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What distinguishes fungi from bacteria?

A

Fungi possesses a rigid cell wall and are very large

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Opportunistic pathogens

A

Fungi and other organisms that are normally not pathogenic that cause infectious disease in immunocompromised patients

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Fungi reproduction
Both sexual and asexual | Fungi are aerobic organisms except the facultative yeast which can grow in both aerobic and anaerobic environments
26
Protozoa
Single spore eukaryores that belong in the animal kingdome Lack cell walls, ingest food particles, and move about ffreely. Most are harmless, except Plasmodium and Giardia
27
Metazoans
Helminths (flukes, flatworms, tapeworms) are multicellular organisms with well developed organ structures. Cannot multiple in their hosts and require reexposure for spread of disease.
28
Most important nonspecific barrier
Skin
29
Lysozyme
Nonspecific destructive enzyme found in human saliva and tears
30
Complement proteins
More than 30 proteins circulating in the blood and involved in both nonspecific and specific host immunity. On invasion, complement may bind to microbial proteins through a process referred to as phagocytosis. Interferons are another form of nonspecific immunity because they trigger the immune system and inhibit viral reproduction. NK cells function to destroy foreign cells while sparing host cells
31
Inflammation
Nonspecific immune system Blood vessels dilate therefore increasing capillary permeability. This action is followed by plasma flow and migration of leukocytes (white blood cells) into the tissue and fluid accumulation Cytokines are also integrally involved in the inflammatory response, including fever development
32
Fever
Controlled by the hypothalamus, defined as a body temp above 37.5 C
33
Proinflammatory cytokines
Interleukins (IL-1, IL-6), TNF-alpha
34
Leukocytes
Neutrophils (60%) Monocytes (5%) Contain enzymes that digest foreign materials after engulfing the invader
35
Macrophages
Mature monocytes May initiate the inflammatory response, release cytokines and neutrophil recruitment Also function as phagocytes in the lymphatic system.
36
Antigens
Chemicals that trigger specific immunity
37
What are the foundational cell line to specific immunity?
Lymphocytes (30% of leukocytes)
38
B vs T lymphocytes
B lymphocytes are largest responsible for antibody mediated immunity T lymphocytes are largely responsible for cell mediated immunity.
39
Immunoglobulin
=antibody
40
Opsonization
Enhancement of phagocytosis by antibodies or complement
41
T-lymphocytes
Originate in the thymus and populate lymph nodes, the spleen, the tonsils, and other lymphoid tissues
42
AMI is used in both viral and bacterial host defense while CMI is essential to
viral host defense
43
Vaccines
Stimulate antibody production as well as T-lymphocytes within the immune system
44
Acute phase response
Incubation period, prodromal period, acme period During this phase selected plasma proteins may be produced in the liver (C-reactive protein, serum amyloid A protein). Elevations in these proteins and globulins may be useful as an indicator of disease and are responsible for increases in the erythrocyte sedimentation rate lab test
45
Bacterial causes of URI
Streptococcus pyogenes and group A streptococcus
46
Strep throat is caused by
Streptococcus pyogenes
47
Epiglottitis is caused by
Haemophilus influenzae
48
Otitis media is caused by
S. pneumonia
49
Pneumonia
Inflammation of the bronchial tubes and lungs
50
CAP bacteria
Often pneumococcus, staph aureus
51
Atypical CAP
Mycoplasma, pneumonia, legionella, pneumophila
52
Athletes foot is caused by
trichophyton species
53
Common organisms related to bladder infections
Proteus mirabilis and E. coli
54
Syphilis
Caused by treponema pallidum Primary- painless ulcers/chancres on external genitalia and mouth Secondary- involves many bodily organs spread through the lymph system and circulating blood Tertiary syphilis- can slowly produce an inflammatory reaction in virtually any organ
55
Primary target of HIV in humans
CD4 cells (helper T cells)
56
Categories of immune cells
Lymphoid (B-lymphocytes, T-lymphocytes, NK cells) | Myeloid- monocytes, macrophages, eosinophils, neutrophils, basophils
57
Innate immunity refers to
the primitive immune response driven by monocytes, macrophages, and neutrophils which recognize pathogens through cell surface interactions and phagocytize them.
58
Antibody chains
Antibodies can produce one of 5 different classes of heavy chains (alpha, gamma, delta, epsilon, mu) and either kappa or lambda light chains. Two identical light and heavy chains comprise a single antibody molecule
59
B-lymphocytes produce _________ as a primary antibody (humoral) response
IgM and then can produce any one of the 5 classes of antibodies in subsequent humoral responses depending on the types of cytokine molecules detected by the B-lymphocyte
60
Epitopes
A discrete portion of the antigen that antibodies recognize and bind to
61
Antibody-epitope binding leads to
B-lymphocyte activation involving internalization, processing, and subsequent presentation of antigen with MHC surface molecules as well as production of cytokines, cytokine receptors, and secreted antibodies.
62
B-lymphocytes present antigens in the context of MHC surface receptors to
T-lymphocytes which then become activated
63
In addition to antigen recognition, antibodies also
have an effector function in which they bind fragment crystallizable (Fc) receptors on the surface of monocytes, macrophages, neutrophils, mast cells, and T-lymphocytes. These receptors are bound by the Fc region of the antibody, comprised of the constant and class-specific region of the heavy chains
64
4 types of hypersensitivity
``` type I (immediate hypersensitivity or allergy) type II (cytotoxic or antibody-dependent [tissue antigen] hypersensitivity) type III (antibody-dependent [soluble antigen] hyper-sensitivity) type IV (delayed-type hypersensitivity). ```
65
Myeloid cells
myeloid cells are either antigen-presenting cells (APCs), such as monocytes and macrophages, or granulocytes, such as eosinophils, neutrophils, and basophils.
66
Function of memory B-cells
Antibody production, antigen presentation
67
Function of plasma cells
Antibody production
68
Function of cytotoxic T cells
killing of infected cells
69
Function of helper t cells
B cell activation
70
Function of Suppressor T cells
reduction of B and T cells immune responses
71
Function of NK cells
Killing of tumor cells and virus infected cells
72
Function of eosinophils
Granule-mediated killing of extracellular pathogens (parasites)
73
Function of monocytes and macrophages
Antigen presentation, phagocytosis
74
Function of neutrophils
Phagocytosis, granule-mediated killing
75
Function of mast cells
Inflammation, allergy
76
Function of basophils
Inflammation, allergy
77
Function of platelets
Blood clotting, inflammation
78
Primary lymphoid organs
Bone marrow and thymus | Produce naive B and T lymphocytes and NK cells
79
Hematopoietic stem cells
Differentiate into B cells or NK cells. In the bone marrow | Differentiate into T cells in the thymus
80
Secondary lymphoid organs and tissues
Spleen, lymph nodes, and mucosa associate lymphoid tissues such as tonsils and Peyer's patches.
81
What happens when a naive lymphocyte enters the secondary lymphoid tissue?
It recognizes a specific antigen presented by APC such as a macrophage. The antigen-MHC complex is bound by an antigen receptor on the lymphocyte (TCR or BCR). The engagement of the antigen-MHC complex and the antigen receptor causes a cascade of events involving production and secretion of cytokines and chemokines This process, called clonal selection is necessary for lymphocyte maturation
82
Do plasma cells proliferate?
No, their function is to produce large amounts of antibodies
83
MHC molecule
``` MHC class I- found on the cell surface on most cells in the body. Present intracellular antigens (antigens from pathogens that live and reproduce inside the host cell) MHC class II- found on the cell surface of APCs and present phagocytosed or internalized antigens from external pathogens ```
84
When is the t lymphocyte activated?
When the TCR-MHC interaction takes place
85
T helper cells express _____ cell surface markers
CD4 in conjunction with the TCR and recognize antigens in the context of MHC class II molecules on APCs
86
Cytotoxic T cells express______
CD8 cell surface molecules in conjunction with the TCR and recognize MHC class I molecules on infected cells
87
Antibody structure
The antibody is composed of 4 chains linked together by covalent bonds: 2 heavy and 2 light chains The variable regions (VL and VH) of the light and heavy chains form an antigen-binding site. Therefore, each antibody has 2 antibody binding sites.
88
Cleavage of an antibody molecule with the cysteine protease papain yields
2 antigen-binding (fab) fragments consisting of one light chain, the VH and CH1 of one heavy vhain, and one fragment crystallizable
89
Fab fragments functions
to bind antigen because they contain an intact antigen-binding site.
90
Fc fragment functions
As an effector portion of the antibody
91
IgA
can be found in the serum, but most often this class of antibody is found as a dimer in mucosal secretions such as saliva, colostrum, milk, tracheobronchial secretions, and urogenital secretions. In its dimerized form, it is referred to as secretory IgA (sIgA).
92
IgG
the predominant class of antibody found in serum, with four subclasses of IgG molecules. IgG collectively is the major antibody class of secondary (memory) humoral responses. It plays a major role in imparting passive immunity to newborns for the first few months of life because maternal IgG passes across the placenta to the fetus.
93
IgD
constitutes a small portion of immunoglobulin found in the serum; however, it is usually found in large quantities on the membrane of B-lymphocytes. The precise function of IgD is unknown, but it may play a role in antigen-triggered lymphocyte differentiation.
94
IgE
least represented antibody class found in the serum. Like IgD, it is overwhelmingly membrane associated, although IgE is found on the surface of mast cells and basophils. Some evidence indicates that this class of antibody participates in immune responses to helminthic parasites; however, in developed countries, it is most associated with allergy-related diseases such as asthma and hay fever.
95
IgM
is found as a pentamer in serum and as a monomer on the cell membrane of B-lymphocytes. It is found on the surface of naive B-lymphocytes and is the antibody class produced in a primary humoral response.
96
Groups of cytokines
Interleukins, TNFs, IFNs, growth factors, chemokines, and colony-stimulating factors

PCOA (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions