BIOMED NOTES 24/25

Factors make microbes thrive: GERM SEP Genetic exchange  Ecological interaction  Rapid reproduction  Metabolic versatility  Small size & large surface area  Extreme adaptability  Pervasive environment presence  Factors govern microbial growth:  Resources: carbon, nitrogen, micronutrients SPK Mg, electron receptor sulphate, inorganic electron donors H2 Environmental: temperature, water, pH, oxygen, light, osmotic conditions  Biological: competition for space and resources, predation, symbiosis  Environment reservoir: ✓ 1. Soil CBB Clostridium tetani  Bacillus anthracis  Burkholderia pseudomallei - wet soil, rice paddy, stagnant water  2. Water Freshwater   Vibrio cholera - flood  Leptospira interrogans - rice field, flood  Free living amoeba   Acanthamoeba - granulomatous encephalitis  Naegleria fowleri - warm freshwater - PAM Biofilms in water systems  LP PA Legionella pneumophila - hosp...

Fungal structure:  Spore sexual: asco, basidio, zygo  Spore asexual: conidia, sporangiospores  Hypha Pseudohyphae  Coneocyte  Septa  Mycelium  Cell wall: chitin, beta glucans, mannans, glycoprotein  Cell membrane: ergosterol  Acquisition → adhesion/colonization → invasion → immune evasion/proliferation → damage  Routes of infection: ✓ Inhale  Trauma/inoculation  Colonization overgrowth  Ingestion  Thermotolerance = able to grow at 37°C  Virulence factors  1. Structural factors  Capsule: galactoxylomannan induces T cell apoptosis, glucoxylomannan inhibit phagocytosis  Melanin - uv, free radicals  2. Enzymatic factors  Protease degrade collagen, elastin, IgA by candida  Phospholipase disrupt membrane by candida, cryptococcus  Urease alkalinize environment by cryptococcus  3. Morphological factors  ✓ Dimorphism  Biofilms  Phenotypic switching = white-opaque chan...

Discussion skills express agreement  That's a great point, and I couldn't agree more. I absolutely agree with your idea. I couldn't agree more with you. That's definitely true because... I'm on the same page as you.  That's a great observation.  express disagreement  I'm sorry but I have to disagree with your point. I'm afraid I can't agree with you on that. I understand your point, but I have to disagree... I'm not convinced by your argument. I have to say that I see things differently. I think there might be some flaws 缺陷in your reasoning because... express partial agreement  Your idea is valid, however... I can see your point, but I also have my own perspective on this issue.  That's a good point, however... You may be right, but... That's true in a way, but... I agree with your point, but I think there's also a different perspective to consider.  when ask question ask opening question  What do you think about... Do you believe...i...

1. structure & function of lungs 2. function & significance of upper respiratory system 3. heart physiology  cardiac cycle cardio function transport nutrients, hormones remove waste products gaseous exchange immunity blood vessels transport blood  pumps blood through blood vessels heart  middle mediastinum inside pericardium oblique behind sternum 1/3 to right blood flow downward, forward, to the left covering - provide protection against friction (friction-free), prevent overfilling, protect & anchor heart + wall fibrous pericardium - conical sac base attach diaphragm anterior attach sternum by sterno pericardial ligaments posterior - principal bronchi, esophagus, descending aorta  lateral - phrenic nerve  serous pericardium  visceral pericardium = epicardium = mesothelium & CT parietal cavity with fluid  parietal pericardium  myocardium = cardiac muscle & involuntary, striated, branched fiber = pump endocardium = simple squam...

cancer define = uncontrolled division of abnormal cells apoptosis = PCD maintain homeostasis when damaged beyond repair, virus, stress, DNA damage  loss of apoptotic control can lead to cancer apoptosis morphology  discontinuous nuclear envelope condensation/shrink blebbing  DNA fragmentation = karyorrhexis apoptotic bodies - phagocytosis necrosis  swelling smooth plasma membrane  disintegration/membrane rupture cell lysis  cancer major changes  immortalization transformation/proliferation angiogenesis  metastasis  evasion of apoptosis  genetic instability  influential factors environment reproductive life  lifestyle virus mutagenic  defect in DNA replication hallmarks evading growth suppressor avoiding immune destruction enabling replicative immortality  tumor promoting inflammation activating invasion & metastasis  inducing angiogenesis  genome instability & mutation resisting cell death deregulati...

energy balance: intake = output positive = intake > output, energy store as glycogen/fat metabolic rate = energy use/time factors hormone - thyroid, insulin exercise body temp age - child higher gender - male higher basal metabolic rate (BMR) = minimum waking rate of internal energy output when rest thyroid hormone - calorigenic effect epinephrine increase BMR food intake appetite center satiety center - fullness, suppress eating arcuate nucleus of hypothalamus  neuropeptide Y increase appetite melanocortin suppress adipocyte  leptin inhibit NPY neuron, stimulate melanocortin neuron pancreas insulin  stomach ghrelin = hunger hormone