什么是ATP，为什么叫能量货币？
What is ATP and why is it called energy currency?
ATP即三磷酸腺苷，是细胞内的直接能量载体，水解末端的磷酸键会释放能量供生命活动使用。细胞靠它统一收付能量，故称能量货币。
ATP, or adenosine triphosphate, is the cell's direct energy carrier; hydrolyzing its terminal phosphate bond releases energy for life processes. Cells use it as a common energy currency, hence the name.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#ATP #能量 #磷酸
一氧化碳中毒的分子机制是什么？
What is the molecular mechanism of carbon monoxide poisoning?
CO以直线型配位到血红素Fe2+上，结合能力比O2强两百多倍，与氧竞争同一配位位点。CO结合后还改变血红素构象，使整个血红蛋白向高亲和态转变，剩余亚基释放氧更困难。结果是氧被血红蛋白锁住、组织供氧中断，严重时可致死；治疗用高压氧舱将CO竞争置换下来。
CO coordinates linearly to the heme Fe2+ with an affinity more than 200 times that of O2, competing for the same binding site. CO binding also changes the heme conformation, shifting the whole hemoglobin toward the high-affinity state so remaining subunits release oxygen even less readily. Oxygen is thus locked up and tissues are starved, which can be fatal; hyperbaric oxygen therapy displaces CO competitively.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
PNAS（血红蛋白构象研究）
PNAS (hemoglobin conformation studies); Nature
#一氧化碳 #血红蛋白 #配位竞争
血红蛋白与氧的结合为什么呈现“协同效应”？其氧合曲线为何是S形？
Why does hemoglobin show 'cooperative' oxygen binding, and why is its oxygen-binding curve S-shaped?
血红蛋白由四个亚基组成，结合一个氧分子后会引起构象由紧张态（T态）向松弛态（R态）转变，使其余亚基更易结合氧，即正协同效应。这种协同性使氧合饱和度对氧分压呈S形（sigmoid）曲线，有利于在肺部高效摄取并在组织中释放氧气。
Hemoglobin has four subunits; binding one O2 triggers a conformational shift from the tense (T) state to the relaxed (R) state, making the remaining subunits bind oxygen more readily—positive cooperativity. This produces a sigmoidal oxygen-saturation curve versus partial pressure, enabling efficient oxygen uptake in the lungs and release in tissues.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
王镜岩等《生物化学》（第三版），高等教育出版社
Wang Jingyan et al., 'Biochemistry' (3rd ed.), Higher Education Press
#血红蛋白 #协同效应 #氧合曲线 #T态 #R态
什么是"玻尔效应"？它如何帮助血红蛋白在组织中释放氧气？
What is the Bohr effect, and how does it help hemoglobin release oxygen in tissues?
玻尔效应指血红蛋白的氧亲和力随 pH 降低（CO₂ 升高）而下降。代谢活跃的组织产生 CO₂ 和乳酸使局部偏酸，血红蛋白构象改变、更容易把结合的氧释放给组织，从而精准匹配供氧需求。
The Bohr effect is the decrease in hemoglobin's oxygen affinity as pH falls (and CO₂ rises). Active tissues produce CO₂ and lactic acid, lowering local pH; hemoglobin then shifts conformation and more readily releases its bound oxygen, matching supply to demand.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-04
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Lehninger《生物化学原理》（第7版），第7章血红蛋白
Lehninger, "Principles of Biochemistry" (7th ed.), Ch.7
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#玻尔效应 #血红蛋白 #氧释放 #pH影响
酶的活性中心如何实现底物专一性？
How does an enzyme's active site achieve substrate specificity?
活性中心的三维形状、电荷与疏水口袋与特定底物精确互补，通过多重弱相互作用锁定并定向底物，使反应沿低能路径进行。Fersht 在《蛋白质科学与机制》中从物理化学量化了这种识别。
The active site's 3D shape, charge pattern and hydrophobic pockets complement a specific substrate, locking and orienting it through multiple weak interactions so the reaction follows a low-energy path. Fersht quantifies this recognition in 'Structure and Mechanism in Protein Science'.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-04
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Lehninger《生物化学原理》；Fersht《蛋白质科学与机制》
Lehninger, Principles of Biochemistry; Fersht, Structure and Mechanism in Protein Science
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#活性中心 #专一性 #弱相互作用
为什么底物浓度足够高时，酶促反应速率不再随底物增加而上升？
Why does enzyme reaction rate stop rising with more substrate once the substrate is plentiful?
酶催化必须先生成酶-底物复合物 ES：E+S 可逆生成 ES，ES 再生成 E+P，反应速率取决于 ES 的浓度。底物浓度低时，ES 浓度与[S]成正比，速率随底物线性上升；底物浓度高时，几乎所有酶分子都被底物占据，ES 达到饱和，速率逼近最大值 Vmax，不再随[S]增加。这一关系用米氏方程描述：v=Vmax[S]/(Km+[S])，其中 Km 是速率达到一半 Vmax 时的底物浓度，反映酶对底物的亲和力，Km 越小亲和力越大。许多药物就是通过占据活性中心、使 Km 增大而 Vmax 不变（竞争性抑制）来起作用的。
Enzyme catalysis must first form the enzyme-substrate complex ES: E + S ⇌ ES → E + P, and the rate depends on how much ES exists. At low substrate, ES grows linearly with [S] and so does the rate; at high substrate nearly every enzyme molecule is occupied, ES saturates, and the rate approaches its maximum Vmax no matter how much more substrate you add. This relationship is the Michaelis-Menten equation, v = Vmax[S]/(Km + [S]), where Km is the substrate concentration giving half of Vmax and reflects the enzyme's affinity for its substrate (smaller Km, tighter binding). Many drugs work by occupying the active site as competitive inhibitors, raising the apparent Km while leaving Vmax unchanged.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
《普通化学》（酶促反应动力学）
General Chemistry (enzyme kinetics)
#米氏方程 #底物饱和 #Km
蛋白质的氨基酸序列为什么就能决定它最终的三维结构？
Why does a protein's amino-acid sequence determine its final three-dimensional structure?
这由蛋白质折叠的能量学决定。疏水氨基酸残基倾向于包埋进内部以避开水分，亲水残基暴露在表面；主链肽键之间形成氢键，侧链之间的离子键和二硫键进一步锁定构象。这些相互作用共同使折叠后的自由能最小化，而氨基酸序列正是这些相互作用的唯一来源，因此一级结构决定三维结构，这就是 Anfinsen 定律（1972年诺贝尔化学奖）。不过折叠通常需要分子伴侣帮助绕开错误折叠的能垒陷阱；折叠一旦异常，会形成聚集体和淀粉样纤维，与阿尔茨海默病、帕金森病等神经退行性疾病有关。
The energetics decide it. Hydrophobic residues pack into the core to escape water while hydrophilic ones stay on the surface; backbone peptide groups hydrogen-bond, and side-chain ionic bonds and disulfide bonds lock the conformation further. Together these interactions minimize the free energy of the folded state, and the amino-acid sequence is their only source - so sequence dictates structure, the Anfinsen principle (Nobel Prize in Chemistry, 1972). Folding usually needs molecular chaperones to dodge the energy traps of misfolding; when it goes wrong, aggregates and amyloid fibrils form, linked to neurodegenerative diseases such as Alzheimer's and Parkinson's.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#蛋白质折叠 #氢键 #错误折叠
米氏方程（Michaelis-Menten equation）描述了什么？米氏常数Km有什么物理意义？
What does the Michaelis-Menten equation describe, and what is the physical meaning of the Michaelis constant Km?
米氏方程 v = Vmax·[S]/(Km + [S]) 描述了酶促反应速率v随底物浓度[S]变化的饱和关系。Km等于反应速率达到最大速率一半时的底物浓度，反映了酶与底物的亲和力——Km越小，亲和力通常越高。
The Michaelis-Menten equation, v = Vmax·[S]/(Km + [S]), describes the saturating relationship between enzyme-catalyzed rate v and substrate concentration [S]. Km is the substrate concentration at which the rate is half of Vmax, and it reflects enzyme-substrate affinity—a smaller Km generally indicates higher affinity.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：作者 / 书名 / 版次 / 出版社 / 年份齐备，仅缺独立比对证据；已在可信度报告单列披露，不再重复核验。
王镜岩等《生物化学》（第三版），高等教育出版社；L. Michaelis & M. Menten,1913
Wang Jingyan et al., 'Biochemistry' (3rd ed.), Higher Education Press; L. Michaelis & M. Menten, 1913
#米氏方程 #酶动力学 #Km #Vmax #底物
什么是光合作用，化学方程式是什么？
What is photosynthesis and what is its equation?
光合作用是植物利用光能把二氧化碳和水转化为葡萄糖并释放氧气的过程。简化方程式为6CO2加6H2O在光照下生成C6H12O6加6O2。
Photosynthesis is the process by which plants use light energy to convert carbon dioxide and water into glucose while releasing oxygen. The simplified equation is 6CO2 plus 6H2O under light giving C6H12O6 plus 6O2.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#光合作用 #葡萄糖 #氧气
血红蛋白怎样实现协同结合氧？
How does hemoglobin achieve cooperative oxygen binding?
血红蛋白四个亚基在结合氧后发生构象变化（T 态转 R 态），使后续亚基更易结合氧，呈 S 形氧合曲线。Perutz 用 X 射线晶体学阐明了这一变构结构基础，协同效应的分子机制在 1970 年的《自然》论文中被系统提出。
Hemoglobin's four subunits change conformation (T to R state) as oxygen binds, making later sites bind more easily and giving a sigmoidal curve. Perutz elucidated this allosteric structural basis by X-ray crystallography, and the molecular mechanism of cooperativity was set out in his 1970 Nature paper.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Lehninger《生物化学原理》；Perutz《自然》1970 年（T↔R 变构机制）
Lehninger, Principles of Biochemistry; Perutz, Nature (1970, T↔R allosteric mechanism)
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#血红蛋白 #协同效应 #变构
为什么 ATP 被叫做细胞的“能量货币”？
Why is ATP called the cell's 'energy currency'?
ATP 末端磷酸酐键水解自由能很高，可在酶催化下把磷酸基转移给受体，直接驱动合成、运输与运动等过程，并能被细胞快速再生。Berg 的《生物化学》将其列为能量偶联的核心分子。
ATP's terminal phosphoanhydride bond releases large free energy on hydrolysis and, enzymatically, transfers its phosphate to drive synthesis, transport and motion, while being rapidly regenerated. Berg's 'Biochemistry' treats it as the central energy-coupling molecule.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Lehninger《生物化学原理》；Berg《生物化学》
Lehninger, Principles of Biochemistry; Berg, Biochemistry
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#ATP #磷酸键 #能量偶联
酶的专一性是什么意思？为什么一种酶通常只催化一种反应？
What does enzyme specificity mean, and why does one enzyme usually catalyze only one reaction?
酶的活性中心是与底物结合并发生催化的特殊三维区域，其形状、电荷分布和疏水环境与特定底物互补，就像锁和钥匙。底物进入后还会诱发酶构象微调，使两者贴合得更紧（诱导契合），催化基团正好对准要断裂的化学键。因此酶的专一性来自底物与活性中心的精确匹配：形状差一点、电荷不对，就结合不牢或无法正确催化。正因如此，淀粉酶只切淀粉、蛋白酶只切蛋白质，细胞才能有条不紊地运行数千个化学反应。
The active site is the special three-dimensional region where an enzyme binds its substrate and performs catalysis; its shape, charge distribution and hydrophobic character complement the specific substrate like a lock and key. Binding also nudges the enzyme into a slightly new conformation that fits the substrate even better (induced fit), lining up catalytic groups against the very bonds to be broken. Specificity therefore comes from precise matching between substrate and active site: slightly wrong shape or wrong charges, and binding fails or catalysis misfires. That is why amylase only cuts starch and proteases only cut proteins, letting the cell run thousands of reactions in orderly fashion.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#酶 #专一性 #活性中心
铅中毒为什么要用螯合剂来治疗？
Why are chelating agents used to treat lead poisoning?
铅离子会与蛋白质中的巯基等结合，干扰酶的功能。螯合剂（如EDTA、二巯基丙醇）分子上有多个配位原子，能像钳子一样同时抓住铅离子，形成稳定的环状配合物，把铅从体内的结合部位抢出来，随尿液排出，从而降低血铅水平。
Lead ions bind to thiol groups in proteins and disrupt enzyme function. Chelating agents such as EDTA and British anti-lewisite have several donor atoms that grip the lead ion like a claw, forming stable ring complexes that pull lead off its binding sites and excrete it in urine, lowering blood lead levels.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03
来源 · Source
《无机化学》配位化合物章节
Inorganic Chemistry (coordination compounds); IUPAC (chelate effect)
#螯合 #EDTA #解毒
酶是什么，它在身体里做什么？
What are enzymes and what do they do in the body?
酶是蛋白质类生物催化剂，能大大加快体内化学反应而不被消耗。例如消化酶帮助我们把食物分解成可吸收的小分子。
Enzymes are protein catalysts that greatly speed up chemical reactions in the body without being consumed. For example, digestive enzymes help break food into small molecules that can be absorbed.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#酶 #蛋白质 #催化
维生素B12分子中含有哪种金属元素？缺少它有什么后果？
Which metal does vitamin B12 contain, and what happens when it is deficient?
维生素B12（钴胺素）分子中心是钴离子，它被一个类似卟啉的咕啉大环配合物包住。人体造血和维持神经系统都依赖维生素B12，缺乏时会出现巨幼细胞性贫血和神经损伤。人体不能自行合成维生素B12，只能主要从肉类、蛋奶等动物性食物中获取。
Vitamin B12 (cobalamin) has a cobalt ion at its center, enclosed by a corrin macrocycle similar to porphyrin. The body depends on vitamin B12 for blood formation and a healthy nervous system; deficiency leads to megaloblastic anemia and nerve damage. Humans cannot synthesize vitamin B12 and must obtain it mainly from animal foods such as meat, eggs and dairy.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-03
来源 · Source
《无机化学》生物无机化学章节
Inorganic Chemistry (bioinorganic chemistry); Nature
#维生素B12 #钴 #咕啉
“锁钥”与“诱导契合”模型有何不同？
How do the 'lock-and-key' and 'induced fit' models differ?
锁钥模型认为酶与底物形状预先完全契合；Koshland 1958 年提出诱导契合，强调结合时酶构象主动调整以更好地包裹底物。后者更好解释了催化中的构象变化与专一性。
The lock-and-key model holds enzyme and substrate pre-fit like a key in a lock; Koshland's 1958 induced-fit says the enzyme actively reshapes on binding to cradle the substrate. The latter better explains conformational change and specificity in catalysis.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：此条未指向带版次的可引用著作（通识性内容、机构文件或未展开的英文书名），本库不提供独立书目出处；如需精确引用，需由编辑补全具体篇目与版次。
Fischer 1894 年锁钥说；Koshland 1958 年诱导契合
Fischer (lock-and-key, 1894); Koshland (induced fit, 1958)
#锁钥模型 #诱导契合 #酶催化
碳酸酐酶为什么必须靠锌离子才能工作？
Why does carbonic anhydrase need zinc to function?
碳酸酐酶催化二氧化碳与水生成碳酸氢根和质子。活性中心的Zn2+与组氨酸配位并拉住一个水分子，使水的pKa降到约7，在中性条件下就能解离出氢氧根，对二氧化碳发起亲核进攻。没有锌，这个反应在中性pH下进行得极其缓慢。
Carbonic anhydrase catalyzes CO2 + H2O to bicarbonate and a proton. The Zn2+ in the active site, coordinated by histidines, holds a water molecule and lowers its pKa to about 7, so hydroxide forms at near-neutral pH and attacks CO2 nucleophilically. Without zinc the reaction proceeds extremely slowly at neutral pH.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-10-03
来源 · Source
《无机化学》生物无机化学章节
Inorganic Chemistry (bioinorganic chemistry); Nature (enzyme structure studies)
#金属酶 #锌 #碳酸酐酶
为什么遗传密码是"简并"的？多个密码子编码同一种氨基酸有什么好处？
Why is the genetic code "degenerate," and what is the benefit of several codons encoding one amino acid?
64 个三联体密码子对应 20 种氨基酸，多数氨基酸由 2–6 个同义密码子编码，这种冗余叫做简并。它使许多突变成为"同义突变"——碱基变了但氨基酸不变，从而缓冲了突变对蛋白质的有害影响，提高容错性。
With 64 triplet codons but only 20 amino acids, most amino acids are encoded by two to six synonymous codons—a redundancy called degeneracy. It turns many mutations into "silent" ones that change the base but not the amino acid, buffering the harmful effects of mutation and improving fault tolerance.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Lehninger《生物化学原理》（第7版），第27章遗传密码
Lehninger, "Principles of Biochemistry" (7th ed.), Ch.27
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#遗传密码 #简并 #同义密码子 #突变容错
酶为什么是高效的生物催化剂？
Why are enzymes such efficient biological catalysts?
酶是蛋白质（或 RNA）催化剂，能大幅降低反应的活化能，常在常温常压下达到极高速率。活性中心通过精确的空间与化学作用稳定过渡态，并具有底物专一性。多数酶受温度、pH 和抑制剂调控。
Enzymes are protein (or RNA) catalysts that greatly lower activation energy, achieving very high rates at mild conditions. Their active sites stabilize the transition state through precise spatial and chemical interactions and show substrate specificity. Most enzymes are regulated by temperature, pH, and inhibitors.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#酶 #活性中心 #过渡态
DNA 的双螺旋结构有什么化学基础？
What is the chemical basis of DNA's double helix?
DNA 由两条反向平行的脱氧核苷酸链组成，通过碱基对之间的氢键配对（A–T、G–C）相互结合。糖-磷酸骨架在外侧，碱基堆叠在内侧，形成右手双螺旋。氢键与碱基堆积力共同维持其稳定。
DNA consists of two antiparallel deoxyribonucleotide strands held together by hydrogen-bonded base pairs (A–T, G–C). The sugar-phosphate backbones lie outside, with bases stacked inside, forming a right-handed double helix. Hydrogen bonds and base stacking together stabilize it.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#DNA #双螺旋 #碱基配对
什么是维生素和矿物质？
What are vitamins and minerals?
维生素是维持健康所需的微量有机化合物，如维生素C。矿物质是无机元素如钙、铁、锌，它们参与骨骼、酶和血液等多种功能。
Vitamins are tiny amounts of organic compounds needed for health, such as vitamin C. Minerals are inorganic elements like calcium, iron, and zinc, which take part in bones, enzymes, and blood functions.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#维生素 #矿物质 #营养
细胞呼吸大致分哪几个阶段？
What are the main stages of cellular respiration?
细胞呼吸主要包括糖酵解、三羧酸循环（TCA）和氧化磷酸化三个阶段。糖酵解在细胞质把葡萄糖分解为丙酮酸，TCA 在线粒体基质彻底氧化，电子传递链通过氧化磷酸化产生大量 ATP。整个过程消耗 O₂ 并放出 CO₂。
Cellular respiration has three main stages: glycolysis, the tricarboxylic acid (TCA) cycle, and oxidative phosphorylation. Glycolysis in the cytosol splits glucose to pyruvate; the TCA cycle in the mitochondrial matrix fully oxidizes it; the electron transport chain makes large ATP via oxidative phosphorylation. The process consumes O₂ and releases CO₂.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#细胞呼吸 #糖酵解 #三羧酸循环
从分子结构看，"反式脂肪"和普通的"顺式"不饱和脂肪有什么不同？为什么反式更不健康？
Structurally, how does "trans fat" differ from ordinary "cis" unsaturated fat, and why is trans worse for health?
不饱和脂肪酸的碳碳双键有顺式或反式两种构型：顺式使碳链弯折、熔点低，多为液态植物油；反式使链较直、更接近饱和脂肪的排列，熔点高。反式脂肪会升高坏胆固醇（LDL）、降低好胆固醇（HDL），增加心血管疾病风险。
Unsaturated fats have cis or trans double-bond geometry: cis kinks the chain and lowers the melting point (liquid oils), while trans keeps it straighter, closer to saturated fats, with a higher melting point. Trans fats raise LDL ("bad") and lower HDL ("good") cholesterol, increasing cardiovascular risk.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
Voet & Voet《生物化学》（第4版），第10章脂类
Voet & Voet, "Biochemistry" (4th ed.), Ch.10 Lipids
#反式脂肪 #顺式 #不饱和脂肪酸 #胆固醇
ATP 在生物体内起什么作用？
What role does ATP play in living organisms?
三磷酸腺苷（ATP）是细胞内的能量货币，其末端的磷酸酐键水解时释放能量驱动各种生命活动。ATP 与 ADP 之间的循环实现了能量的捕获、储存与释放。呼吸作用和光合作用都为其合成提供能量。
Adenosine triphosphate (ATP) is the cell's energy currency; hydrolysis of its terminal phosphoanhydride bond releases energy to power life processes. The ATP/ADP cycle captures, stores, and releases energy. Respiration and photosynthesis supply the energy for its synthesis.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#ATP #能量货币 #磷酸键
葡萄糖在体内氧化释放的能量比直接点燃多得多，为什么细胞要分步进行？
Glucose yields far more usable energy in the body than if burned directly - why do cells oxidize it in small steps?
一步燃烧放出的热能又猛又烫，细胞无法储存，还会损坏蛋白质。细胞把葡萄糖经糖酵解、三羧酸循环和氧化磷酸化分解成几十个小步骤，每一步只释放少量能量，并用它合成高能分子 ATP（1分子葡萄糖约可产生30到32个 ATP）或还原型辅酶。这样能量以 ATP 形式被打包储存，按需支取，效率远高于一步燃烧。分步还能让细胞对能量需求精细调控，比如缺氧时切换到产能较少的糖酵解应急。
One-step burning dumps energy as heat - too fast and too hot to store, and destructive to proteins. Instead the cell chops glucose through glycolysis, the citric-acid cycle and oxidative phosphorylation into dozens of small steps, each releasing a little energy that is captured to make the high-energy molecule ATP (about 30-32 ATP per glucose) or reduced coenzymes. Energy is packaged into ATP and spent on demand, far more efficiently than a single burst of burning. The stepwise design also allows fine control - in low oxygen the cell shifts to the less productive glycolysis to keep running.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#糖酵解 #三羧酸循环 #ATP
磷脂为什么能形成生物膜？
Why can phospholipids form biological membranes?
磷脂分子有一端亲水的头部和两条疏水的尾部，属于两亲分子。在水中它们自发排列成双层，亲水头朝外接触水、疏水尾朝内避水，构成细胞膜的基本骨架。这种自组装是生物膜形成的基础。
Phospholipids have a hydrophilic head and two hydrophobic tails, making them amphiphilic. In water they spontaneously arrange into a bilayer with heads outward toward water and tails inward, forming the basic framework of cell membranes. This self-assembly underlies biological membranes.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#磷脂 #双分子层 #两亲分子
为什么人会缺钙？
Why do people lack calcium?
钙是骨骼和牙齿的主要成分，也参与神经和肌肉信号。饮食中奶类、豆制品不足或维生素D缺乏都会影响钙吸收，导致缺钙。
Calcium is the main component of bones and teeth and also takes part in nerve and muscle signals. Too little dairy or soy in the diet, or a lack of vitamin D, can impair calcium absorption and cause deficiency.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#钙 #骨骼 #维生素D
为什么章鱼和螃蟹的血是蓝色的？
Why is the blood of octopuses and crabs blue?
这些动物用血蓝蛋白结合并运输氧气，其核心是铜离子，含氧的血蓝蛋白呈蓝色，所以它们的血液偏蓝；而人类血红蛋白以铁离子为核心，含氧时呈鲜红色。氧分子都是以配位键结合到金属离子上，只是金属不同，颜色和输送方式就不同，这是金属配位化学在生物中的典型例子。
These animals use hemocyanin, which binds and transports oxygen around a copper ion; the oxygenated copper protein is blue, so their blood looks bluish. Human hemoglobin, by contrast, uses iron and turns bright red when oxygenated. In both cases oxygen coordinates to a metal ion - only the metal differs, and with it the color and transport strategy. It is a classic example of metal coordination chemistry in biology.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-03
来源 · Source
《无机化学》生物无机化学章节
Inorganic Chemistry (bioinorganic chemistry); Nature
#血蓝蛋白 #铜 #氧运输
酶的“诱导契合”学说（induced-fit model）是什么？它比“锁钥”模型好在何处？
What is the 'induced-fit' model of enzyme action, and how is it an improvement over the 'lock-and-key' model?
诱导契合学说认为，底物靠近酶时并非被动嵌入现成口袋，而是诱导酶活性中心的构象发生适应性变化，使催化基团精确就位。相比把酶看作刚性模板的锁钥模型，它更好地解释了酶对底物的广谱适应性与催化高效性。
The induced-fit model holds that as a substrate approaches, it induces a conformational change in the enzyme's active site so catalytic groups are positioned precisely—rather than the substrate simply dropping into a preformed pocket. Compared with the rigid lock-and-key model, it better explains enzymes' broad adaptability and high catalytic efficiency.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：作者 / 书名 / 版次 / 出版社 / 年份齐备，仅缺独立比对证据；已在可信度报告单列披露，不再重复核验。
王镜岩等《生物化学》（第三版），高等教育出版社；D. E. Koshland,1958
Wang Jingyan et al., 'Biochemistry' (3rd ed.), Higher Education Press; D. E. Koshland, 1958
#酶 #诱导契合 #活性中心 #构象 #锁钥模型
ATP水解为什么能为细胞的生命活动提供能量？其标准自由能变化大约是多少？
Why can ATP hydrolysis supply energy for cellular activities, and what is its approximate standard free-energy change?
ATP（三磷酸腺苷）水解为ADP和磷酸时释放大量自由能，主要原因是产物中磷酸基团间的静电斥力被解除、且产物比反应物更稳定（共振与溶剂化更好）。在标准生化条件下其ΔG°′约为−30.5 kJ/mol，细胞借此驱动合成、运输、运动等耗能过程。
ATP (adenosine triphosphate) releases substantial free energy when hydrolyzed to ADP and phosphate, mainly because electrostatic repulsion among its phosphate groups is relieved and the products are more stable (better resonance and solvation). Under standard biochemical conditions ΔG°′ is about −30.5 kJ/mol, energy the cell uses to drive synthesis, transport, and movement.
难度 进阶 · 适合 高中(15-18)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录含书名，但缺版次 / 出版社 / 年份中的一部分，需编辑补全后才能做独立比对。
王镜岩等《生物化学》（第三版），高等教育出版社
Wang Jingyan et al., 'Biochemistry' (3rd ed.), Higher Education Press
#ATP #水解 #自由能 #ADP #能量货币
为什么叶绿素的中心离子是镁，而血红蛋白的中心离子是铁？
Why is the central ion of chlorophyll magnesium, but that of hemoglobin iron?
两种色素都围绕金属离子搭建出卟啉类的大环配合物：叶绿素是含镁的卟啉配合物，血红蛋白是含铁的卟啉配合物。镁离子使叶绿素能够吸收红光和蓝光进行光合作用，镁的缺失会导致叶片发黄；铁离子则能与氧可逆配位，负责运输氧气。金属离子的选择不是随意的，它由配体结构与功能需求共同决定，同样的大环配不同的金属，就有截然不同的生物功能。
Both pigments are built as porphyrin-like macrocyclic complexes around a metal ion: chlorophyll is a magnesium porphyrin and hemoglobin an iron porphyrin. The Mg²⁺ lets chlorophyll absorb red and blue light for photosynthesis - when magnesium is missing, leaves turn yellow - while Fe²⁺ coordinates oxygen reversibly and carries it around the body. The choice of metal is not arbitrary; it was shaped together with the porphyrin scaffold and the biological job. The same macrocycle with different metals performs entirely different functions.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#叶绿素 #血红素 #金属离子
DNA是由什么化学物质组成的？
What chemicals is DNA made of?
DNA由四种含氮碱基、脱氧核糖和磷酸组成，碱基排列顺序储存遗传信息。两条链缠绕成著名的双螺旋结构。
DNA is made of four nitrogenous bases, deoxyribose sugar, and phosphate, and the order of bases stores genetic information. Two strands wind into the famous double helix.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#DNA #碱基 #双螺旋
DNA双螺旋中碱基是如何配对的？靠什么作用力维持？
How are the bases paired in the DNA double helix, and what force holds them together?
在DNA中，腺嘌呤（A）专一地与胸腺嘧啶（T）配对，鸟嘌呤（G）专一地与胞嘧啶（C）配对，称为碱基互补配对。这些配对依靠碱基之间的氢键维系（A-T形成两个氢键，G-C形成三个氢键），氢键的数目也解释了G-C对更为稳定。
In DNA, adenine (A) pairs specifically with thymine (T) and guanine (G) with cytosine (C), a rule called complementary base pairing. The pairs are held together by hydrogen bonds—two between A and T, three between G and C—and the extra bond explains why G-C pairs are more stable.
难度 入门 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-04
来源 · Source
沃森与克里克（Watson & Crick）,《Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid》,Nature,1953 (DOI: 10.1038/171737a0)；王镜岩《生物化学》
Watson & Crick, 'Molecular Structure of Nucleic Acids: A Structure for Deoxyribose Nucleic Acid', Nature, 1953, DOI: 10.1038/171737a0; Wang Jingyan, 'Biochemistry'
独立核验依据 · Independent verification: 核验依据 1 Crossref DOI 10.1038/171737a0
#DNA #碱基配对 #氢键 #双螺旋 #互补
蛋白质是由什么构成的？氨基酸如何连接？
What are proteins made of and how are amino acids linked?
蛋白质由 20 种常见氨基酸通过肽键（–CO–NH–）脱水缩合连成多肽链。氨基酸的排列顺序决定蛋白质的一级结构，进而折叠成特定三维构象以执行功能。酶、抗体、肌肉蛋白都属此类。
Proteins are built from 20 common amino acids linked by peptide bonds (–CO–NH–) through dehydration. The amino-acid sequence is the primary structure, which folds into a specific 3D conformation for function. Enzymes, antibodies, and muscle proteins are all proteins.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 来源待核验 · Source pending review
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#蛋白质 #氨基酸 #肽键
什么是生物化学？
What is biochemistry?
生物化学是研究生命体内化学物质的组成、结构和变化的科学。它帮助我们理解食物如何变成能量、基因如何传递信息。
Biochemistry is the science of the composition, structure, and changes of chemical substances inside living organisms. It helps us understand how food becomes energy and how genes pass on information.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#生物化学 #生命 #分子
维生素 C 在人体内起什么作用？
What role does vitamin C play in the human body?
维生素 C（抗坏血酸）是水溶性抗氧化剂，能清除自由基并参与胶原蛋白的合成。它还是某些羟化酶的辅因子，缺乏会导致坏血病。人体不能自行合成，须从果蔬中摄取。
Vitamin C (ascorbic acid) is a water-soluble antioxidant that scavenges free radicals and aids collagen synthesis. It also serves as a cofactor for certain hydroxylases; deficiency causes scurvy. Humans cannot synthesize it and must obtain it from fruits and vegetables.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 来源待核验 · Source pending review
来源 · Source
出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#维生素C #抗氧化 #坏血病
为什么我们的身体既需要蛋白质也需要糖类（碳水化合物）？
Why does our body need both proteins and carbohydrates?
糖类是身体的"快能源"，分解后能迅速供能；蛋白质由氨基酸组成，用来建造和修复肌肉、酶、皮肤等身体结构。两者功能不同、缺一不可：缺糖会没力气，缺蛋白会长不好、修不了组织。
Carbohydrates are the body's quick energy source, breaking down to fuel activity fast; proteins, built from amino acids, construct and repair muscles, enzymes, and skin. They serve different roles—without carbs you lack energy, without protein you can't grow or repair tissue.
难度 入门 · 适合 幼儿(3-6)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Lehninger《生物化学原理》（第7版），第1章
Lehninger, "Principles of Biochemistry" (7th ed.), Ch.1
独立核验依据 · Independent verification: 核验依据 1 ISBN 978-1-319-45541-5 (8th ed., Macmillan Learning)
#营养 #蛋白质 #碳水化合物 #能量
为什么血液是红色的？
Why is blood red?
血液红色来自红细胞中的血红蛋白，它含有与氧结合的铁原子。含氧时呈鲜红，缺氧时偏暗红。
Blood is red because of hemoglobin in red blood cells, which contains iron atoms that bind oxygen. It appears bright red when oxygenated and darker red when not.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#血红蛋白 #铁 #氧
我们吃下的食物在体内变成了什么？
What does the food we eat become inside the body?
食物在消化道里被分解成糖、氨基酸和脂肪酸等小分子，再进入细胞通过化学反应释放能量或建造身体。未被吸收的部分变成废物排出。
In the digestive tract, food is broken into small molecules like sugars, amino acids, and fatty acids, which enter cells and release energy or build the body through chemical reactions. What is not absorbed becomes waste.
难度 入门 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Brown, LeMay 等,《Chemistry: The Central Science》第14版,Pearson,2017
T. L. Brown et al., Chemistry: The Central Science, 14th ed., Pearson, 2017
#消化 #能量 #营养
光合作用的总反应式是什么？
What is the overall equation of photosynthesis?
绿色植物在光照下把二氧化碳和水转化为葡萄糖并释放氧气：6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂。该过程在叶绿体中进行，把光能转化为储存在糖中的化学能。它是地球碳氧循环的核心。
In light, green plants convert carbon dioxide and water into glucose while releasing oxygen: 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂. Occurring in chloroplasts, it turns light energy into chemical energy stored in sugar. It is central to Earth's carbon and oxygen cycles.
难度 入门 · 适合 幼儿(3-6)
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出处备注：著录仅给书名，无版次与年份；同一书名常对应多个版次，不臆测具体版本。
王镜岩《生物化学》
Biochemistry (Wang Jingyan)
#光合作用 #叶绿体 #葡萄糖