week 2 Flashcards
Microbiology, integumentary system, lymphatics/ immune system
Microorganisms
living organisms
reproduce independently
are everywhere
Prokaryotes (list some characteristics)
small always unicellular no nucleus no cytoskeleton asexual
Eukaryotes (list some characteristics)
Lagre often multi-cellular has nucleus has cytoskeleton sexual or asexual (mitosis/ meiosis)
Types of prokaryotes and eukaryotes
protozoa - eukaryote fungi - eukaryote helminths - eukaryote virus - not living bacteria - prokaryote
Growth requirements
TEMP: optimal - 37 C
Thermophile - 60 C
Mesophiles - 25-30 C
Pyschrophiles - 10 C
PH: 7 neutral
OXYGEN:
aerobes - in the presence of oxygen
anaerobic - without the presence of oxygen
facultative anaerobes - with or without oxygen
Gram-negative and gram-positive bacteria
gram-negative - capable of forming spores
gram positive - most difficult to kill, produce endotoxins
Normal flora (3 locations + characteristics)
skin - reduces pH
oral + vagina - completes + inhibits pathogens + yeast
intestine - excrete bacteria, synthesise + secrete vitamins and stimulate immunity
Mode of transmission
air-borne contact water-borne blood + tissue borne vector-borne fomite-borne vertical
Chain of infection (list the parts)
infectious agent reservoir portal of exit means of transmission portal of entry susceptible host
Skin layers
epidermis
dermis
hypodermis/ subcutaneus
Epidermis role
protects underlying tissue from: dehydration infection mechanical stress chemical stress UV radiation
Dermis role
strength + flexibility
thermoregulation
protection
sensation
Hypodermis/ subcutaneus role
insulation + thermoregulation
protection
storage
Cell types - epidermis
keratinocyte
langerhans
merkel
melanocyte
Thermoregulation (3 parts)
vasoconstriction - increase blood pressure, skin veins constrict in cold weather to conserve heat
vasodilation - decrease blood pressure, skin veins dilate in hot weather to lose heat
goosebumps and sweat - other methods of losing and conserving heat
Lymphatic system components
immune cells
lymph - fluid tissue
lymph vessels -organs
Functions of lymphatic system
drain excess fluid + proteins from all tissues back to blood circulation
transport fats and vitamins from gut to liver (digestion)
defends the body against external and internal threats
Immunity (definition)
ability to resist infection + disease
immune system has two parts:
- non-specific defences
- specific defences
Lymphocytes
are white blood cells, are 3 types (B cells,T cells and natural killer cells)
recognise antigens, produce antibodies, and destroy cells that could cause damage
Respond to:
environmental pathogens
toxins
abnormal body cells
mature in the bone marrow or thymus
Lymph tissue
is a fluid contains lymphocytes + macrophages that seek out and destroy enemies - foreign cells - foreign proteins - cancer cells
Lymph organs
lymph flows through special tubes from tissue to the large veins and heart
tubes: lymph capillaries, vessels, trunks and ducts
Lymphatic capillaries
have one-way valves
allows fluids, solutes, viruses and bacteria to enter
prevents return to inter-cellular space
Lymph vessels
thin walls
resemble veins with more valves
lymph nodes at intervals
Lymph ducts
vessels unite to form 2 thoracic ducts
right side - right lymphatic duct
left side - main thoracic duct
Lymph nodes
filter lymph: foreign materials enter,foreign matter is trapped in fibres and then destroyed by macrophages , B & T cells
Label a bacteria cell
capsule cell wall cytoplasm plasmid cell membrane chromosome flagellum ribosomes
Label skin structure
capillaries hair follicle sensory neurons fat sebaceuous (oil) glands sweat glands
