Life and the cell
| English | Chinese | Pinyin |
|---|---|---|
| biology | 生物学 | shēng wù xué |
| cell | 细胞 | xì bāo |
| prokaryotic | 原核 | yuán hé |
| eukaryotic | 真核 | zhēn hé |
| homeostasis | 稳态 | wěn tài |
What counts as alive
- Biology 生物学 studies living things, and the definition is a checklist rather than a single property.
- A living thing takes in energy, responds to its surroundings, grows, reproduces, and maintains itself.
- Fire spreads and consumes fuel; a crystal grows. Neither does all of it, which is why the list is a list.
Which are on the checklist for a living thing? Choose all that apply.
Fire consumes fuel and spreads; a crystal grows. Neither does everything on the list.
The cell
- The cell 细胞 is the unit of life: the smallest thing that does everything on that list.
- Prokaryotic 原核 cells have no nucleus and are small and simple — bacteria.
- Eukaryotic 真核 cells have a nucleus and internal compartments — everything else.
- The difference is roughly a billion years of evolution, not a detail of labelling.
Match each cell type to its defining feature.
The difference is roughly a billion years of evolution, not a labelling detail.
Homeostasis
- Homeostasis 稳态 is keeping internal conditions steady while outside conditions change.
- Body temperature, water balance, blood sugar: all held within narrow limits by constant correction.
- ⚠ It is active, not passive. Staying the same takes continuous work, and that work is what stops when an organism dies.
Homeostasis means the body stays the same and does nothing.
It changes constantly — sweating, shivering, releasing hormones — to hold one measurement steady.
Give one example of homeostasis and name the mechanism that does the work.
Example: "Body temperature is held near 37°C, and sweating cools the body when it rises."
Is a virus alive?
It has genetic material and it reproduces — but only inside a host cell, using that cell's machinery. It does not take in energy or maintain itself.
The honest answer is that it fails part of the checklist, which is why biologists disagree about it.
A question like this is not testing whether you know a fact. It is testing whether you can apply a definition to a case it was not written for, and say which criteria fail.
Why do biologists disagree about whether a virus is alive?
It reproduces, but only inside a host, and it neither takes in energy nor maintains itself.
A definition in biology is usually a cluster of criteria, not a single test. Species, life, and even the gene are like this — and questions are often built on the cases at the edge, where the criteria disagree.
Do not describe homeostasis as "the body staying the same". It is the body changing constantly in order to keep one measurement steady — sweating, shivering, releasing hormones — and the mechanisms are what the marks are for.