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1 Primary & Middle School Mathematics1–9 年级在线 2 High School Mathematics10–12 年级在线 3 University Mathematics — Year 1本科一年级在线 4 University Mathematics — Year 2本科二年级在线 5 University Mathematics — Year 3本科三年级在线

1 Primary & Middle School Physics1–9 年级在线 2 High School Physics10–12 年级在线 3 University Physics — Year 1本科一年级在线 4 University Physics — Year 2本科二年级在线 5 University Physics — Year 3本科三年级在线

1 School Chemistry — Grades 1 to 121–12 年级在线 2 University Chemistry — Year 1本科一年级在线 3 University Chemistry — Year 2本科二年级在线 4 University Chemistry — Year 3本科三年级在线

1 Primary & Middle School Biology1–9 年级在线 2 High School Biology10–12 年级在线 3 University Biology — Year 1本科一年级在线 4 University Biology — Year 2本科二年级在线 5 University Biology — Year 3本科三年级在线

1 Primary & Middle School Earth and Space Sciences1–9 年级在线 2 High School Earth and Space Sciences10–12 年级在线 3 University Earth and Space Sciences — Year 1本科一年级在线 4 University Earth and Space Sciences — Year 2本科二年级在线 5 University Earth and Space Sciences — Year 3本科三年级在线

1 Markets I: The Ecosystem and Exchange-Traded Markets市场在线 2 Markets II: Rates, FX and Credit市场在线 3 Markets III: Commodities, Energy and Crypto市场在线 4 Quantitative Methods方法在线 5 Derivatives and Volatility衍生品在线 6 Rates, Credit, XVA and Risk利率、信用与风险在线 7 Research Craft: Predictors, Backtests, Measurement, Portfolios研究在线 8 Strategies I: Equities and Futures策略在线 9 Strategies II: Volatility, Relative Value, Macro and the Bank Desks策略在线 10 Microstructure and Execution交易执行在线 11 Market Making and High-Frequency Trading做市在线 12 Machine Learning for Markets机器学习在线 13 Low-Latency Software技术在线 14 Networks, Hardware and Trading Infrastructure技术在线 15 Research, Data and Risk Platforms技术在线 16 The Desk and the Firm公司运营在线 17 The Industry: Firms, Roles and Careers职业发展在线 18 Interviews I: Maths, Probability and Speed职业发展在线 19 Interviews II: Markets, Trading Games and the Final Round职业发展在线 20 Interviews III: Code职业发展在线

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Biology · 术语表

什么是 Seed？

又称： germ (of a seed)

Definition 9.1 Primary & Middle School Biology · 第 9 章 — From Seed to Plant

A seed is the beginning of a new plant, made by the parent plant. Inside its protective coat, a seed holds:

a tiny plant already started — the germ of the plant, with the beginnings of a root and a shoot;
a store of food to feed it until it can feed itself.

Inside the soaked, opened bean: a tiny plant — root tip and folded first leaves — lying against its food store.

示例

Example 9.2 (Opening a soaked bean)

Soak a big white bean overnight, and its coat slips off easily. The bean opens into two thick halves — the food store — and there, nestled at one edge, lies a tiny pale plant, root tip and folded first leaves, small as a grain of rice. The new plant was there all along.

Example 9.6 (Why sowing waits for spring)

Gardeners sow beans in spring, not in winter: the seed in cold earth would wait — or rot — instead of germinating. Warm days and watered soil are exactly the two signals of Proposition 9.5.

Example 9.10 (One bean, one summer)

Sown in May, a bean germinates in a week; by June it is a leafy plant climbing its pole; in July come white flowers, then green pods; in August the pods hang heavy, each holding a row of new beans — next year’s seeds, made by this year’s plant.

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