Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Infection And Immunity > Infection > Flashcards

Infection Flashcards

(98 cards)

Start Studying
1
Q

Describe bacterial cells

A

Lack nuclear membrane and organelles
Cell wall
Cocci and bacilli
Binary fission

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

Describe a viral cell

A

DNA can be single/double, circular/linear, RNA/DNA
This is surrounded by a capsomere coat
Nucleocapsid surrounded by lipid bilayer of host cell origin
Enveloped more susceptible to drying, acidity, and bile

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

Describe Fungi

A

Eukaryotes
Thick chitin cell wall
Grow as filaments or single cells
Superficial or deep infections

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

Evidence for the endosymbiotic origin of mitochondria

5

A

Ribosomes are more like prokaryotic ones
Have a circular form of DNA
Control their own division
Production of energy associated with inner membrane as in prokaryotes
Antibiotics which affect bacterial ribosomes will also affect mitochondria

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

Microbial classification techniques

5

A

Macroscopic- growth patterns, size, texture, pigment
Microscopic- size, shape, arrangement of cells
Antigenic properties- determines the relatedness
Subcellular- molecular constituents for taxon/organism group
DNA base composition ratio- extent to which DNA is G/C based

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

Definition of epidemiology

A

Study of distribution and determinants of a disease within human populations. Occurence, risk, treatments, progression, diagnostic test performance.

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

Early history of infectious diseases

A

Soil, water, lifestyle
Practical anatomy experiments on gladiators
The plague- quarantine and body disposal
Leprosy- quarantine little effect

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

Ebola
Location
Description

A 
Emerged in Guinea
Filovirus
Negative sense ssRNA genome
5 species and 2 related filo viruses
Contact with infected bats and monkeys, 
Causes necrosis of liver, spleen, lymph nodes and lungs
Haemorrhagic symptoms after 7-15 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Strain variation- Zairean + Reston Ebola viruses

A

90% case fatality rate in the zaire strain
0% fatality in the Reston strain
Fatal inflammatory response ‘cytokine Storm’
Can cause inflammatory sequela after clearance of the virus

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

Inactivation of virus on skin

A

Inactivated by desiccation, ph 5.5, inhibitors formed by commensal organisms

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

Human papilloma virus

A

Circular dsDNA genome, non enveloped
Infect the basal layer of differentiating epithelium
Causes warts, sometimes cancerous
Causes cervical cancer- first cancer vaccine

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

Influenza

A

Orthomyxovirus
Segmented negative sense ssRNA genome
Types A and B cause most disease
Upper respiratory tract, antigenic shift and drift
Spreads through epithelium contained by structure

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

Polio virus

A 
Picornavirus
Positive sense ssRNA genome
Small unenveloped virus
3 serotypes
2 vaccines available
Fecal oral transmission

Poliomyelitis (paralysis) and muscle weakness
Epithelium -> lymph node -> blood -> muscle, liver spleen -> blood
Then spreads to multiple infection sites

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

Gram wall in bacteria

A

+ve - 20-80nm peptidoglycan layer, topped by lipoteichoic acid. Highly polar and lipophillic so can resist bile action.
-ve - 5-10nm thick, overlaid by outer membrane

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

Flagella and pili

A

Independent of ATP
Pili provide protection and attach to other bacteria
Antigen can be changed to avoid recognition, constant and variable pili regions

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

Arrangement of cocci

A 
Dipplococci in paid
Streptococci in chains
Clusters = staphylococci
2 planes = tetrads
3 planes = sarcinae
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Arrangement of bacilli

A

Single rods
Diplobacilli in pairs
Streptobacilli in pairs
Coccobacilli short and wide

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

Spirochaetes

A

Vibrios- Curved rods
Spirilla- Helical shape and rigid bodies
Spirochetes- helical shape and flexible bodies
Move by axial filaments

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

Growth phases of bacteria

A

Lag phase
Exponential phase
Stationary phase
Death phase

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

Targets for anti microbial agents

A

Quinolones which inhibit the unwinding of DNA

Inhibitors of peptidoglycan wall synthesis

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

Types of staphylococcus
Diseases
Treatment

A

Gram negative
Scalded skin, boils, toxic shock, impetigo
Protein A - interacts with IgG reducing opsonisation
Penicillin, methicillin, vancomycin

Epidermis- device related sepsis e.g. Catheter. Extra cellular slime causes bio films

Saprophyticus- UTI of intercourse, colonises skin and mucosa

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

Types of streptococcus

A

Gram +ve, pairs and chains,
Pyogenes- URT and skin. Scarlet fever, rheumatic fever and glomerulonephritis
Transmitted by airborne droplets and contact
Treated by penicillin/vancomycin

Agalactiae- neonatal meningitis and septicaemia. Penicillin and gentamicin

Pneumoniae- haemolytic colonies. Pneumonia, septicaemia, meningitis. Capsule protects from phagocytosis. Viral infection may be a precursor, penicillin and vaccine.

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

Trichomonas vaginalis

A

Causes trichomoniasis, common STD
Multiples by binary fission
Irritation, inflammation, burning although 70% asymptomatic

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

Giardia intestinalis

A 
Causes giardiasis -> diarrheal disease
Protected by shell to live outside the body, resistant to chlorine
Cysts ingested in food/water
Cyst -> trophozoites -> cysts
Cysts passed in stools
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Naegleria fowleri
Primary amoebic meningoencephalitis Cyst -> flagellated trophozoites Enters with water into nasal mucosa Migrate to brain via olfactory nerve
26
Trypanosoma brucei
Typanosomiasis Trypomastigotes enter bite wound -> amastigotes inside cells Multiply by binary fission in cells of infected tissues Changes VSG coat Inflammation -> winter bottoms sign -> neurological -> coma/death
27
Entamoeba Histolytica
``` Acute dysentery, liver abscess, necrotic colitis GI tract -> liver Ingested or blood stream Cysts -> trophozoites Divide by binary fusion Infect brain liver and lungs WBCs die by necrosis when contacted 80% mortality when abdomen infected ```
28
Blastocystis
``` Parasites Live within GI tracts Vaculor Granular Ameboid (causes symptoms) Cyst (survives stomach acid) ```
29
Cryptosporidium
Causes cryptosporidiosis No drug to deal with infection Oocysts -> meront -> zygote -> oocysts
30
Toxoplasma gondii
Carried in cats, but can have intermediate hosts Causes toxoplasmosis 1/3 of population infected, high as 84% in France Tachyzoites -> bradyzoites -> merozoites -> amastigotes -> trypomastigotes
31
Plasmodium
Causes malaria Liver cells form schizont -> ruptures Trophozoites -> rozet -> gametocytes -> sporogenic cycle Oocysts rupture and restart cycle Malaria attack, anaemia and rosetting
32
Trypanosome cruzi
Chagas' disease- romana sign and fever. Chronic phase cardiomyopathy and heart aneurysma. Megaesophagus and mega colon. Fecal oral Amastigotes in heart -> trypomastigotes -> bug bite
33
Leishmania
Parasites carried in sand flies Leishmaniosis Skin lesion, destroys nose, abdominal swelling
34
How are fungi classified
Growth- filamentous/yeast Infection- superficial/deep mycoses Divided into 3 groups: Obligate- dermatophytes which attack external structures Soil fungi- tolerate high temps and are dimorphic Opportunistic saprobes- attack when immunocompromised
35
Tinea infections | Superficial mycosis
Caused by ringworm Capitis- infects hair, treated by 40% KOH Tinea corporis- round ring on skin, skin scrapings Tinea ungium- damaged nails, associated with Candida albicans Tinea pedis- athletes foot. High normal flora, cracking, lipophillic and lipophobic bacteria -> smell S.aureus causes secondary infection and pus This then causes more infection by E.coli -> necrosis Colonisation with pseudomonas causing permanent damage and trench foot
36
Superficial Candidosis
Most common is genital by Candida albicans Chronic mucocutaneous candidiasis, oropharyngeal, oesophaegeal, gastrointestinal and disseminated. Risk factors- neutropenia and damage of gastrointestinal mucosa, venous catheters, antibacterials, surgery
37
Tinea versicolour | Superficial mycosis
Caused by pityroporon orbiculare Chronic skin condition Looks pink-brown un tanned, but white on tanned.
38
Mycetoma | Superficial
'Madura foot' Tropics Granulomatous lesion which is surrounded by a dense fibrous capsule Muscle tendon and bone eventually destroyed
39
Chromoblastomycosis | Superficial
Raised crusted lesions Several fungi in soil and wood Inoculated into skin by minor injury Warmer areas such as Pacific
40
Sporotrichosis | Subcutaneous mycosis
Sporothrix schenckii 75% lymphocutaneous Primary inoculation -> painless nodules along lymphatic vessels Nodules drain the primary lesion
41
Coccidiomycosis C.immitis Subcutaneous
``` C. Immitis growth occurs in 2 phases - mycelial arthrospore in soil - spherule endospore in infected tissues As soil dries they become airborne Leads to respiratory infection, spherules are formed in lungs ```
42
Systemic mycosis | C.immitis
Respiratory infection -> endobronchiolitis Pulmonary markings, bronchopneumonia, pleural effusion. IgG and IgM react
43
Disseminated coccidomycosis Systemic mycosis Risk factors
Weeks to months of primary pneumonia Males and African ethnic groups more likely Depressed cellular immunity Skin, bones, joints and meninges
44
Microsporidia (phylum) | Systemic mycosis
Protozoa classified as fungi -> biochemical and physiologically alike Affect individuals with low CD4 T cells Encephalitozoon cuniculi- 2000 proteins in genome Intestinal- diarrhoea, gallbladder disease Lungs- cough, fluid in lungs Can spread to UTI, kidney, brain, pancreas, muscle Eye infections
45
7 functions of the skin
``` Support Temperature Excretion Vitamin formation Sensory function Pigmentation Protection ```
46
Factors that cause variation in the skin microbiome
Host physiology Environment Immune system Host genotype (fillagrin susceptibility gene) Lifestyle Pathobiology (underlying conditions diabetes)
47
Apocrine gland of skin
Scent gland found near sex organs
48
Eccrine gland of skin
3 portions: Acrosyringium Intradermal duct Secretory coiled gland Produces eccrine sweat ACH -> ion exchanges -> eccrine duct reabsorbes NaCl and HCO3 Sweat passed through acrosyringium and deposited on cell surface
49
Sebaceous gland of the skin
Cells detach from basal membrane and fill with lipid Hurts and sebum is expressed into the hair follicle Sex hormones -> NaATPase system Bacteria and skin block sebum from escaping pores S.aureus causes boils Tinea versicolour- fat and lipid spreads over skin
50
Acid mantle
Sebaceous sac contains fungi and bacteria Esterases -> convert fat to long fatty acid chains Cause bacteriocidal skin effect Sebum + sweat = acid mantle Lactate buffering systems Bacteria evade by producing urease
51
Impetigo
S.aureus and s.pyogenes | Face in angles of mouth and nose. Yellow crusted scabs.
52
Toxic shock syndrome
Tampon use Fever, hypotension and rash, desquamation of skin TSST1 exotoxin behaves as a super antigen Shock + organ damage -> organ failure
53
Lepromatous leprosy
Mycobacterium leprae Live in Schwann cells Loss of sensation -> ulceration due to injury and tissue loss
54
Tuberculoid leprosy
Hypersensitivity reaction Formation of granulomatous changes within epithelial, lymphocytes and langerhans Thickening of nose, ears and forehead
55
Describe eukaryotic cells
``` Bigger than bacterial True nucleus Membrane bound organelles Cytoskeleton Cell division through mitosis ```
56
What does the upper respiratory tract contain
Nose, sinus, larynx, nasal cavity, ethmoidal air cell
57
Defence mechanisms of the URT
Tears, lysosomes, sigA, lactoferrin Nasopharynx- micro flora, lysozyme, sigA Lungs- macrophages
58
Diptheria | URT infection
Corynebacterium diphtheria, gram +ve Lysogenised by beta phage- tox genes on phage chromosome Induces production of EF-2 Prevents elongation of proteins in the ribosomes Catalytic A peptide transfers ADP ribose from NAD to EF2 and inhibits protein synthesis
59
Middle ear- Otis media
New air unable to reach middle ear -> Eustachian tube dysfunctions Body absorbs remaining air creating a vacuum Negative pressure then fills vacuum with fluid Inflation of Middle ear, antibiotics
60
Epiglottitis
Infection of epiglottis, airway obstruction Haemophillus influenza type B, rarely strep or pneumococcus URT -> epiglottis Bacteria in the blood
61
Parotitis | URT
Mumps virus Respiratory tract -> lymph nodes Secondary viraemia to the salivary glands, pancreas, sex organs, CNS MMR vaccine
62
Oral cavity herpes
Latent in sensory never ganglia Cold sores UV irradiation, dryness and cracking
63
Oral cavity Candidiasis
Candida albicans penetrates the epithelium with pseudo mycelia Treatment with anti fungal agents
64
Viral infections of the LRT
Invade bronchiolar epithelium, can spread to alveoli -> pneumonia Affected cells congested and haemorrhagic Hyaline membranes Bacterial infection may also develop
65
Bacterial infections of the LRT | Pneumonia
Streptococcus pneumoniae Lodges in bronchioles, outpour of protein rich fluid in alveoli Stages of infection Congestion- vascular engoregement and bacterial proliferation Red hepatisation- air spaces filled with polymorph nuclear cells, extravasation of RBCs Grey hepatisation- accumulation of fibrin, disintegration of WBCS and RBCs Resolution- resorption of the exudates
66
Bacterial infections of the LRT | Tuberculosis
Nearly 1/3 of world population Initial infection- positive skin test, dormant Activation after immunosuppression
67
Fungal infection of the LRT
Aspergillus -> farmers lung Grows in cavities from TB Fungal ball invades tissues Surgery to remove
68
Upper tact bacteruria
Bacteria in urine collected from the renal pelvis or ureter | Organisms present in Both in vesicouretic reflux
69
Acute bacterial pyelonephritis
Acute infection of the kidneys accompanied by fever, loin pain, pyuria, bacteriuria and bacteraemia
70
Chronic bacterial pyelonephritis
Chronic inflammation of renal and tubular tissue with scarring and shrinkage, interstitial fibrosis Loss of GFR and ability to concentrate urine Caused by Bacterial infection Vesico ureteric reflux Intra renal reflux
71
Bacterial causes of UTIS
Gram -ve rods from GI tract E.coli (P antigen) Proteus, pseudomonas, enterobacter Staphylococcus, chlamydia Have fimbriae which bind to glycoproteins and glycolipids P antigen- blood group marker on UT cells
72
Virulence factors in UTI
Fimbriae- agglutinate RBCs, can bind to UT wall Glycocalyx- capsules, slime layers. Reduce adhesion to phagocytes and antibodies. Sialic acid prevents complement activation
73
Staphylococcus saprophyticus in UTI
Strong adherence, found in feet. | Associated with hormone activity
74
4 types of urine sample
Mid stream- sample taken after initial urination Catheter- sample from later flow Supra public aspiration- patient unable to give clean catch Early morning- used for culture
75
Protective mechanisms of the vagina
Acid ph Lactobacilli Yeast IgA
76
Formation and maintenance of normal flora in vagina
Glycogen levels at birth increases lactobacilli Enterococci and coli form appears At puberty glycogen raised again At menopause glycogen decreases
77
Herpes simplex
Type 2 70-90% Lesions and burning after 1 week Painful urination, walking and sitting Virus then latent, inflamed lesions when activated. No cure.
78
Gonorrhoea
Neisseria gonorrhoea, gram -ve diplococci Pain during urination, discharge Mainly asymptotic in women -> pelvic inflammatory disease Scar tissue in ducts Newborns develop gonococcal Neoopthalmia -> blindness
79
Syphilis
Treponema pallidum Primary- sores Secondary- skin rash and mild fever -> latent Tertiary- extensive tissue damage, paralysis, insanity, death Resistance to antibiotics increasing
80
Anaerobic vagiosis
Gardnerella vaginalis Grayish thin discharge Odour when vagina ph alkaline by aromatic amines
81
Thrush
Candida albicans Clumping discharge Redness, swelling
82
Scabies
Mite sarcoptes scabiei Itching due to allergic reaction Rash of raised spots
83
Viral meningitis
More common, less serious Herpes simplex, mumps, enteroviruses, HIV Main cause is the coxsackie virus found in sewage polluted water
84
Bacterial meningitis
Haemphilus influenzae b- grows in presence of haematin and NAD. Vaccine avaliable. Neisseria meningitis- petechiae, fever, headache, stiff neck Often part of throat flora Can kill in hours Meningococcal vaccine but not against B strain
85
Chronic meningitis
Damage to skull Brain abscesses Mass puts pressure on brain tissue
86
Conjunctivitis
Inflammation of conjunctiva | S.aureus, influenza, pneumonia. Caused in newborns by mother infected with STI
87
Keratitis
Inflammation of cornea After injury Acanthomoeba keratitis- using tap water to clean contacts
88
Endopthalmitis
Common after cataract surgery, s.epidermis
89
Blepharitis
``` Inflammation of eyelids Burning, itching Staphylococcal Seborrheic Meibomiam gland dysfunction ```
90
Canaliculitis
Uncommon unilateral infection Candida albicans aspergillus Removal of necrotic material
91
Host defences of GI tract
Normal flora- 400+ Abnormal colonisation of upper GI tract by e.coli and Vibro cholera. Resident bacteria produce bacteriocins which inhibit abnormal flora, Antibiotics can alter flora Salmonella and Shigella.
92
Diseases causes by overgrowth of GI flora
Clostridium difficile- colon inflammation and diarrhoea. Caused by antibiotics.
93
Gastric acidity
People with achlorydria have excessive numbers of microbes in the upper bowel.
94
Norwalk virus GI
Vomiting, cramps and diarrhoea, fever, headache | Associated with shellfish
95
Campylobacter sp. GI
Diarrhoea, pain, fever Undercooked meat Relapses may occur
96
Salmonella and GI
Infection in lining of small intestine Some people carry for 1 year + Food storage, lizards, infected family
97
Shigella and GI
Nom motile gram -ve Invades the intestinal mucosa Micro abscesses -> large Fever, cramps, dysentery
98
Enteroparasites and GI
Entamoeba Histolytica Dysentery, mucus and blood Cysts in stools Areas of epithelium area sloughed off as it burrows

Infection And Immunity (2 decks)

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