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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 Parts of a plant？

又称： root · stem · leaf · flower

Definition 3.4 Primary & Middle School Biology · 第 3 章 — Plants Around Us

A flowering plant has four main parts:

the roots, hidden in the soil, which hold the plant in place and drink water;
the stem, which stands the plant up and carries water to the leaves;
the leaves, flat and green, which catch the light;
the flower, which will make the seeds.

The four parts of a flowering plant, shown pulled up whole: in the ground, the roots do their work out of sight, under the soil.

示例

Example 3.5 (Pulling up a weed)

Pull a weed gently out of loose, wet earth and you bring up the hidden part: a tuft of pale roots, sometimes longer than the whole green plant above. Now the plant can be read from bottom to top: roots, stem, leaves — and, if you are lucky, a flower.

Example 3.7 (The chestnut tree)

The chestnut tree in the yard has the same plan as the daisy, but bigger and harder: roots under the ground, a trunk instead of a soft stem, branches with thousands of leaves, and in spring, flowers. The daisy lives one year; the chestnut can live longer than a hundred.

Example 3.9 (The forgotten plant)

Forget to water the classroom plant before the holidays: its leaves hang down, soft and sad — it wilts. Water it, and a few hours later the leaves stand up again. Water was the missing need.

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