Fungi and parasites
Đã giới thiệu| English | Ý nghĩa |
|---|---|
| sporozoite | sporozoite |
| merozoite | merozoite |
| gametocyte | gametocyte |
| dimorphic fungus | dimorphic fungus |
Two hosts, one clock
- Malaria: mosquito injects sporozoites → liver schizonts → erythrocytic merozoites cycling in red cells → gametocytes taken up by the next mosquito ✓.
- Synchronous bursting every 48 h (tertian) or 72 h (quartan) makes the fever periodic: the parasite's clock IS the symptom's clock.
Thick film: rings in ~3 % of erythrocytes plus crescent gametocytes → P. falciparum: morphology names the species and grades severity in one look ✓.
{exercise:uni-med0804-tertian} {exercise:uni-med0804-falciparum}
A 48-hour fever periodicity (tertian) reflects —
Độ khó 1/5 · 100 xu + phần thưởng nhỏ khi hoàn thành lần đầu tiên hôm nay
Vivax and ovale burst in step every 48 h (tertian); malariae every 72 h (quartan). The parasitaemia clock is the fever clock.
P. falciparum is the killer because it —
Độ khó 1/5 · 100 xu + phần thưởng nhỏ khi hoàn thành lần đầu tiên hôm nay
Poor synchrony makes fevers irregular, and cytoadherence (sequestration) drives organ disease - the exception that the cycle rule explains.
Dimorphism as an identity card
- A dimorphic fungus grows as a mould at 25 °C and a yeast at 37 °C — the thermostat switch doubles as its identity card ✓.
- Opportunists follow MED07's defect map: T-cell failure → Pneumocystis, Candida; neutrophil failure → Aspergillus.
{exercise:uni-med0804-dimorph}
A culture growing as a mould at 25 degrees and a yeast at 37 degrees identifies —
Độ khó 1/5 · 100 xu + phần thưởng nhỏ khi hoàn thành lần đầu tiên hôm nay
The thermostat switch (mould in the environment, yeast in tissue at 37 degrees) is the dimorphic fungi identity card.