表观遗传（如 DNA 甲基化）如何不靠改序列来遗传信息？
How can epigenetics (e.g., DNA methylation) inherit information without changing the sequence?
DNA 甲基化、组蛋白修饰等化学标记能在细胞分裂时部分保留，开关基因却不改动碱基序列，并可受营养与环境影响。Bird 在 2002 年综述了 CpG 甲基化如何沉默基因，Wolffe 与 Matzke 1999 年讨论了其可遗传性。
Marks like DNA methylation and histone modification are partly maintained through cell division, switching genes on or off without altering bases and responding to diet and environment. Bird reviewed how CpG methylation silences genes in 2002; Wolffe and Matzke discussed its heritability in 1999.
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。
Bird 2002 年综述；Wolffe 与 Matzke 1999 年论文；Lodish《分子细胞生物学》
Bird (2002 review); Wolffe & Matzke (1999); Lodish, Molecular Cell Biology
#表观遗传 #DNA甲基化 #基因沉默
实时荧光定量PCR（qPCR）是如何定量检测DNA的？
How does real-time quantitative PCR (qPCR) quantify DNA?
qPCR在每个扩增循环中同步检测荧光，通过Ct值定量：使用SYBR Green荧光染料（结合双链DNA发光）或TaqMan探针（利用FRET，探针被Taq酶5'到3'外切活性水解后释放荧光）。荧光信号随产物指数增长而增强，达到设定荧光阈值所需的循环数（Ct值）与初始模板拷贝数成反比，模板越多Ct越小。通过与已知浓度标准品作出的标准曲线比较，即可精确定量。若先以RNA为模板用逆转录酶合成cDNA（RT-qPCR），则可检测基因表达水平。
qPCR detects fluorescence at each amplification cycle and quantifies via the cycle threshold: SYBR Green dye, which fluoresces when bound to double-stranded DNA, or a TaqMan probe, a FRET-based probe cleaved by Taq's 5'-to-3' exonuclease activity, reports product accumulation. The number of cycles needed to reach a set fluorescence threshold (Ct value) is inversely proportional to the starting template copy number; more template means a smaller Ct. Comparing against a standard curve from known concentrations gives absolute quantification; using reverse transcriptase to make cDNA from RNA first (RT-qPCR) allows measurement of gene expression.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#实时定量PCR #Ct值 #TaqMan探针
上位效应与传统的显性关系有何本质区别？
How does epistasis fundamentally differ from simple dominance?
显性描述同一基因座等位基因间的关系，而上位效应是一个基因座的基因产物掩盖或修饰另一基因座的表达，例如决定小鼠毛色的多个基因座相互作用，属于基因间的非加性关系。
Dominance describes allele interactions at one locus, whereas epistasis is when one locus masks or modifies the expression of another—such as multiple coat-color loci in mice interacting—representing non-additive inter-gene relationships.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#上位效应 #基因互作 #表型
什么是基因组？
What is a genome?
基因组是一个生物体内全部遗传信息的总和，包括所有基因和非编码DNA，决定了它的全部潜能。
A genome is the complete set of an organism's genetic information—all genes and non-coding DNA—defining its full potential.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#基因组 #遗传信息 #DNA
什么是显性基因和隐性基因？
What are dominant and recessive genes?
显性基因在杂合时即可表现性状，隐性基因需成对出现才表现；例如两个携带者可能生下表现出隐性病的孩子。
A dominant allele shows its trait even with one copy, while a recessive allele shows only when both copies are present.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#显性 #隐性 #等位基因
什么是表观遗传？
What is epigenetics?
表观遗传研究在不改变DNA序列的情况下，化学标记如何开关基因，并可能受环境和生活方式影响而传给后代。
Epigenetics studies chemical marks that switch genes on or off without changing the DNA sequence, sometimes influenced by environment and passed to offspring.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#表观遗传 #基因开关
转座子为何被称为基因组中的跳跃基因？
Why are transposons called jumping genes of the genome?
转座子是可从基因组一处移动到另一处的 DNA 序列，通过剪切-粘贴或复制-粘贴机制改变位置，既能促进基因组重排和进化，也可能插入关键基因引起突变或疾病。
Transposons are DNA sequences that move from one genomic location to another via cut-and-paste or copy-and-paste mechanisms, driving genomic rearrangement and evolution while potentially disrupting genes and causing disease when inserted.
难度 专业 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#转座子 #基因组 #突变
神农架传说有“白化”动物（白熊、白鹿），白化到底是怎么产生的？
Shennongjia is said to harbor “albino” animals—how does albinism arise?
白化多由控制黑色素的基因突变（如酪氨酸酶基因）导致，使毛发、皮肤和眼睛缺黑色素。神农架湿度大、光照弱、相对隔离，近亲繁殖概率高，使隐性白化基因更易显现，但白熊多为黑熊的个别白化个体而非新物种。
Albinism usually stems from mutations in melanin genes (e.g. tyrosinase), leaving hair, skin and eyes without pigment. Shennongjia's humid, dim, isolated habitat raises inbreeding odds, letting recessive albino genes show; the “white bears” are mostly albino Asiatic black bears, not a new species.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#白化 #基因突变 #神农架
什么是基因组印记？
What is genomic imprinting?
基因组印记是一种表观遗传现象：某些基因的表达取决于它们来自父本还是母本，即同一基因的两个等位基因中仅一方被标记并表达。这种亲本来源特异的甲基化标记会影响胚胎发育，印记异常可导致普拉德-威利综合征等疾病。
Genomic imprinting is an epigenetic phenomenon in which certain genes are expressed depending on whether they came from the father or the mother, only one parental allele is marked and expressed. These parent-of-origin methylation marks affect development, and their disruption causes disorders such as Prader-Willi syndrome.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#基因组印记 #表观遗传 #亲本来源 #甲基化
什么是表观遗传，它与普通基因突变有何不同？
What is epigenetics, and how does it differ from ordinary genetic mutation?
表观遗传研究在不改变 DNA 序列的前提下，由 DNA 甲基化、组蛋白修饰等化学标记调控基因开关的机制。这些修饰可受饮食、压力等环境因素影响并可能遗传给后代，但不属于 DNA 碱基序列本身的突变。
Epigenetics studies mechanisms—such as DNA methylation and histone modifications—that switch genes on or off without changing the DNA sequence. Such modifications can be influenced by environmental factors like diet and stress and may be inherited, yet they are not mutations of the base sequence itself.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#表观遗传 #DNA甲基化 #组蛋白修饰
非编码 RNA 有什么作用？
What is the function of non-coding RNA?
非编码 RNA 是不翻译成蛋白质的 RNA 分子，却广泛参与基因调控。例如 tRNA 和 rRNA 参与翻译机器，microRNA 与 siRNA 通过降解或抑制 mRNA 来沉默基因，长链非编码 RNA 则在染色质重塑和发育中发挥调节作用。
Non-coding RNAs are RNA molecules that are not translated into protein yet broadly regulate genes. tRNA and rRNA are part of the translation machinery, while microRNAs and siRNAs silence genes by degrading or blocking mRNA, and long non-coding RNAs help remodel chromatin and steer development.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《分子生物学》
Molecular Biology of the Cell (Alberts)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787030261946（豆瓣书目条目: 分子生物学）
#非编码RNA #microRNA #tRNA #基因沉默
基因编辑在镰刀型贫血治疗中是如何应用的？
How is gene editing applied in treating sickle cell disease?
镰刀型贫血由 β-珠蛋白基因突变引起，使红细胞扭曲成镰刀状。2023 年获美国 FDA 批准的疗法（如 exa-cel）通过 CRISPR-Cas9 编辑患者自身造血干细胞，重新激活胎儿血红蛋白基因，从而缓解症状。
Sickle cell disease is caused by a mutation in the beta-globin gene, distorting red blood cells into a sickle shape. Approved by the U.S. FDA in 2023 (e.g., exa-cel), therapy uses CRISPR-Cas9 to edit a patient's own blood stem cells and reactivate fetal hemoglobin genes, easing symptoms.
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。
美国食品药品监督管理局（FDA）2023 年批准公告；《新英格兰医学杂志》（NEJM）
U.S. FDA approval announcement (2023); New England Journal of Medicine (NEJM)
#镰刀型贫血 #基因治疗 #胎儿血红蛋白
人类基因组里有多少DNA是不编码蛋白质的"非编码"部分，它们有用吗？
How much of the human genome is non-coding DNA, and does it serve any purpose?
在人类约30亿个碱基对中，真正编码蛋白质的外显子只占约1%–2%，其余近98%为非编码DNA，包含内含子、重复序列和大量调控元件。这些序列并非全是"垃圾DNA"，许多参与基因表达的开关、染色体结构的维持与基因组的稳定性。
Of the roughly 3 billion base pairs in the human genome, protein-coding exons make up only about 1–2%; nearly 98% is non-coding DNA, including introns, repeats, and a wealth of regulatory elements. Far from being all "junk," much of it controls when and where genes switch on and helps maintain chromosome structure and genome stability.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
国际人类基因组测序联盟，《人类基因组的初步测序与分析》，《自然》2001年
International Human Genome Sequencing Consortium, "Initial sequencing and analysis of the human genome," Nature (2001)
独立核验依据 · Independent verification: 核验依据 1 EUROPEPMC 标识 11237011：Initial sequencing and analysis of
#非编码DNA #人类基因组 #基因调控 #垃圾DNA
什么是遗传漂变？
What is genetic drift?
遗传漂变是指小群体中基因频率因随机偶然事件而改变的现象，与自然选择无关。例如少数个体建立新群体时（奠基者效应），某些基因可能意外增多或减少。它在小种群中对进化的影响尤为显著。
Genetic drift is the random change in gene frequencies in a small population due to chance events, unrelated to natural selection. For example, when a few individuals found a new group, the founder effect can make some genes unexpectedly rise or fall. Its evolutionary impact is especially strong in small populations.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#遗传漂变 #进化 #随机
哈迪-温伯格平衡成立需要哪些前提条件？
What conditions must hold for Hardy-Weinberg equilibrium?
群体需满足随机交配、无突变、无自然选择、无基因流且群体无限大；任一条件被打破都会导致等位基因频率改变，因此该平衡常被用作检验进化是否发生的零模型。
The population must have random mating, no mutation, no selection, no gene flow and infinite size; violation of any condition shifts allele frequencies, so the equilibrium serves as a null model for detecting evolution.
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。
《群体遗传学》教材
Evolutionary Analysis
#哈迪温伯格 #群体遗传 #进化
Sanger（链终止）测序法的基本原理是什么？
What is the basic principle of Sanger (chain-termination) sequencing?
Sanger法利用2',3'-双脱氧核苷三磷酸（ddNTP）终止DNA链合成：ddNTP缺少3'-羟基，被DNA聚合酶掺入后下一个核苷酸无法连接，合成随即终止。测序反应中按比例混入少量标记的ddATP/ddTTP/ddCTP/ddGTP，与正常dNTP竞争，产生末端分别在A/T/C/G处终止、长度各异的片段库。现代自动化版本用四种不同荧光标记的ddNTP在单管反应中完成，经毛细管电泳按长度分离，激光检测器逐个读出荧光颜色，即得到碱基序列。
Sanger sequencing exploits 2',3'-dideoxynucleoside triphosphates (ddNTPs), which lack a 3'-hydroxyl group: once incorporated by DNA polymerase, no further nucleotide can be added and synthesis stops. A small proportion of labeled ddATP, ddTTP, ddCTP, and ddGTP is included with normal dNTPs, producing a library of fragments terminated randomly at each A, T, C, or G. Modern automated versions use four fluorescently labeled ddNTPs in a single reaction, separate the fragments by capillary electrophoresis by length, and a laser detector reads the color at each position to reveal the sequence.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#Sanger测序 #双脱氧核苷酸 #链终止
什么是无义突变，细胞如何阻止它产生有害的截短蛋白？
What is a nonsense mutation, and how does the cell stop it from making harmful truncated proteins?
无义突变把原本编码氨基酸的密码子变成终止密码子，使蛋白质在中间被提前截断。细胞拥有"无义介导的mRNA降解"（NMD）这一质控通路，能识别并降解带提前终止密码子的异常转录本，避免积累可能有毒的截短蛋白。
A nonsense mutation converts a sense codon into a stop codon, truncating the protein prematurely. Cells deploy nonsense-mediated mRNA decay (NMD), a quality-control pathway that detects and degrades transcripts carrying premature stop codons, preventing the buildup of potentially toxic truncated proteins.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Watson 等，《基因分子生物学》（第7版，Pearson，2012）
Watson et al., Molecular Biology of the Gene (7th ed., Pearson, 2012)
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL222777W：Molecular biology of the
#无义突变 #mRNA降解 #蛋白质合成 #质控
孟德尔的分离定律和自由组合定律究竟在讲什么？它们和减数分裂有什么联系？
What exactly do Mendel's law of segregation and law of independent assortment say, and how do they connect to meiosis?
分离定律指每个基因都有两份等位基因，在形成配子时成对等位基因彼此分开，每个配子只带其中一份，所以杂合子会产生两种配子，比例约为1:1。自由组合定律指位于不同染色体上的基因在配子形成时互不干扰地组合，这正是减数第一次分裂中期同源染色体随机排列在赤道板、后期同源染色体彼此分开的结果。两定律本质上就是减数分裂的遗传学表述：同源染色体分开带来“分离”，非同源染色体的自由组合带来“独立分配”，而连锁基因因同处一条染色体而不服从自由组合定律。
The law of segregation states that every individual carries two alleles of each gene, and these paired alleles separate when gametes form, so each gamete receives just one copy; a heterozygote therefore produces the two gamete types in roughly a 1:1 ratio. The law of independent assortment says genes on different chromosomes combine independently during gamete formation, a direct outcome of the random orientation of homologous chromosomes at the metaphase I plate and their separation at anaphase I. Both laws are essentially the genetics of meiosis: separation of homologs gives segregation, while the independent shuffle of non-homologous chromosomes gives independent assortment, and linked genes on the same chromosome do not obey the second law.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《普通生物学》(陈阅增)
General Biology (Chen Yuezeng)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040583151（豆瓣书目条目: 陈阅增普通生物学）
#分离定律 #自由组合 #减数分裂
分子进化的“中性学说”主张什么？
What does the neutral theory of molecular evolution claim?
木村资生在 1968 年提出，大多数分子水平的突变是中性的，其频率主要由随机漂变而非自然选择决定，因此进化速率大致恒定。它补充而非否定自然选择，解释了大量同义替换的积累。
Kimura proposed in 1968 that most molecular mutations are neutral and their frequencies drift randomly rather than being driven by selection, so the molecular clock ticks roughly steadily. It complements rather than denies selection, explaining the accumulation of synonymous substitutions.
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。
木村资生 1968 年《自然》论文；Lewontin《进化生物学》
Kimura (1968, Nature); Lewontin, population genetics
#中性学说 #随机漂变 #分子钟
CRISPR-Cas9 为什么被称为“基因剪刀”？它具体是怎样编辑基因的？
Why is CRISPR-Cas9 called "molecular scissors," and how exactly does it edit genes?
CRISPR-Cas9 由两部分组成：一段能与目标 DNA 互补配对的向导 RNA，和一个切割 DNA 的 Cas9 核酸酶。向导 RNA 带着 Cas9 找到基因组里大约20个碱基的目标位点（还需要 PAM 序列确认），Cas9 随即切断两条 DNA 链。细胞修复断裂时如果走非同源末端连接，往往产生小的缺失或插入导致基因失活；如果同时提供一段供体模板，细胞就会用同源重组把想要的序列精确写入。它便宜、快速、可编程，但脱靶切割和伦理问题仍是应用中的关注点。
CRISPR-Cas9 has two parts: a guide RNA that base-pairs with the target DNA, and the Cas9 nuclease that cuts it. The guide RNA escorts Cas9 to a site of roughly 20 bases in the genome (confirmed by a PAM sequence), and Cas9 then cuts both strands. If the cell repairs the break by non-homologous end joining, small insertions or deletions usually appear and knock the gene out; if a donor template is provided, the cell can copy the desired sequence in precisely through homology-directed repair. It is cheap, fast and programmable, though off-target cuts and ethical questions remain concerns in real-world use.
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。
Nature（CRISPR 综述，2020）
Nature (CRISPR review, 2020)
#CRISPR #Cas9 #基因编辑
为什么有性染色体，剂量如何补偿？
Why are there sex chromosomes, and how is dosage compensated?
哺乳动物雌性有两条 X、雄性一条，为避免 X 连锁基因剂量翻倍，雌性在发育早期随机让一条 X 染色体失活形成巴氏小体，称为 X 失活。Lyon 在 1961 年提出这一机制，由 Xist 长链 RNA 介导。
Female mammals have two X chromosomes and males one; to avoid doubling X-linked gene dose, females randomly silence one X into a Barr body early in development, called X-inactivation. Lyon proposed this in 1961, mediated by the Xist long RNA.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Lyon 1961 年论文；Alberts《细胞的分子生物学》
Lyon (1961); Alberts, Molecular Biology of the Cell
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL7938488W：Molecular Biology of th
#性染色体 #X失活 #剂量补偿
经典的基因敲除小鼠是如何构建的？
How is a classic gene-knockout mouse constructed?
经典方法利用胚胎干细胞（ES细胞）的同源重组：构建靶向载体，其中目的基因外显子被新霉素抗性基因（neo）替换，同源臂外侧连有HSV-tk基因。载体电转入ES细胞后，发生同源重组的细胞把neo整合进靶位点而丢失tk；用G418筛选（获得neo）加更昔洛韦负筛选（排除随机插入、保留tk的细胞）即得到正确重组的克隆。将阳性ES细胞显微注射入囊胚，形成含两种细胞来源的嵌合体小鼠，经生殖系传递获得杂合子，再交配得到纯合敲除小鼠。该技术由Capecchi、Smithies等建立，获2007年诺贝尔生理学或医学奖，现多被CRISPR-Cas9替代。
The classic approach relies on homologous recombination in embryonic stem (ES) cells: a targeting vector replaces an exon of the gene of interest with a neomycin resistance gene (neo), with a herpes simplex virus tk gene placed outside the homology arms. After electroporation, cells that undergo homologous recombination integrate neo at the target locus and lose tk; positive selection with G418 plus negative selection with ganciclovir (killing random-integrants that retain tk) isolates correctly recombined clones. Injected into blastocysts, these ES cells produce chimeric mice, which transmit the mutation through the germline to give heterozygotes, and intercrossing yields homozygous knockouts. Established by Capecchi, Smithies, and others (2007 Nobel Prize in Physiology or Medicine), the method has largely been replaced by CRISPR-Cas9.
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。
Nature（Capecchi 等基因打靶研究）
Nature, gene targeting in embryonic stem cells
#基因敲除 #同源重组 #胚胎干细胞
染色体是什么？人有几条？
What are chromosomes, and how many do humans have?
染色体是打包好的DNA长链，人每个细胞正常有46条（23对），其中一半来自父亲，一半来自母亲。
Chromosomes are packaged DNA strands; a normal human cell has 46 (23 pairs), half from each parent.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#染色体 #23对
为什么线粒体 DNA 通常只通过母亲遗传？
Why is mitochondrial DNA usually inherited only from the mother?
受精时，精子的线粒体主要集中在尾部而不进入卵子，因此受精卵中的线粒体几乎全部来自卵细胞。由于线粒体拥有自己的环状 DNA，这种母系遗传使科学家能用线粒体 DNA 追溯人类的母系祖先。
At fertilization, a sperm's mitochondria are concentrated in its tail and generally do not enter the egg, so the mitochondria in the zygote come almost entirely from the oocyte. Because mitochondria carry their own circular DNA, this maternal inheritance lets scientists trace human maternal ancestry.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#线粒体DNA #母系遗传 #人类学
DNA 突变如何产生又怎样被修复？
How do DNA mutations arise and how are they repaired?
复制错误或紫外线、化学物可造成碱基错配、断裂等损伤；细胞有错配修复、核苷酸切除修复等多种系统识别并替换错误。Lindahl 与 Sancar 因阐明修复机制获 2015 年诺贝尔化学奖。
Replication errors or UV and chemicals cause mismatches and breaks; cells use mismatch repair, nucleotide-excision repair and more to recognize and replace damage. Lindahl and Sancar won the 2015 Nobel Prize in Chemistry for clarifying these mechanisms.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Alberts《细胞的分子生物学》；Lindahl、Sancar（2015 诺奖）
Alberts, Molecular Biology of the Cell; Lindahl & Sancar (Nobel 2015)
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL7938488W：Molecular Biology of th
#DNA修复 #突变 #核苷酸切除修复
为什么雌性哺乳动物（包括人类女性）的两条X染色体只有一条正常工作？
Why do female mammals use only one of their two X chromosomes for most genes?
雌性有两条X染色体而雄性只有一条（XY），为平衡X连锁基因的剂量，胚胎早期会随机让其中一条X染色体失活，浓缩成可见的"巴氏小体"（由Xist RNA包被）。这使雌雄X连锁基因表达量大致相等，也令雌性成为细胞层面的嵌合体，如玳瑁猫的花斑就源于此。
Females carry two X chromosomes while males have one (XY); to equalize X-linked gene dosage, one X is randomly silenced early in development and condenses into a visible Barr body coated by Xist RNA. This balances expression between sexes and makes females cellular mosaics—as seen in the patchy coat of calico cats.
难度 进阶 · 适合 小学高段(9-12)
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。
Mary F. Lyon，《小鼠X染色体的基因作用》，《自然》1961年
Lyon, "Gene action in the X-chromosome of the mouse," Nature (1961)
#X染色体失活 #剂量补偿 #Xist #巴氏小体
凝胶电泳是如何按大小分离DNA片段的？
How does gel electrophoresis separate DNA fragments by size?
DNA分子含磷酸基团，带负电，在电场中会向正极迁移。琼脂糖凝胶具有分子筛效应：分子量小的片段穿过凝胶孔隙快、迁移距离远，大的片段移动慢，因此不同大小的DNA被分离开形成条带。用溴化乙锭、SYBR Green等荧光染料染色后可在紫外灯下观察条带，通过与已知大小Marker比较判断片段大小；还可切下目的条带回收DNA用于克隆等后续实验。
DNA is negatively charged because of its phosphate backbone and migrates toward the anode in an electric field. Agarose gel acts as a molecular sieve: small fragments thread through the pores quickly and travel far, while large fragments move slowly, so fragments of different sizes separate into discrete bands. After staining with fluorescent dyes such as ethidium bromide or SYBR Green, bands are visualized under UV light and sized against a ladder of known markers; bands can be excised to purify DNA for downstream applications such as cloning.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#凝胶电泳 #DNA分离 #琼脂糖
什么是性染色体？
What are sex chromosomes?
性染色体决定性别：人类女性为XX，男性为XY，它们携带与性别发育相关的基因。
Sex chromosomes determine sex: human females are XX and males XY, carrying genes for sex development.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#性染色体 #性别 #XY
减数分裂中的基因重组是如何发生的？
How does genetic recombination occur during meiosis?
在减数分裂前期 I，同源染色体联会时可能发生交叉互换，使非姐妹染色单体之间交换 DNA 片段。再加上后期 I 同源染色体的随机分配，子代就会获得不同于双亲的全新基因组合，这是有性生殖产生遗传多样性的主要来源。
During prophase I of meiosis, homologous chromosomes pair up and can exchange DNA segments through crossing over between non-sister chromatids. Combined with the random assortment of homologous chromosomes at anaphase I, offspring receive novel gene combinations, the main source of genetic diversity in sexual reproduction.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《遗传学》
Genetics: A Conceptual Approach (Pierce)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040351590（豆瓣书目条目: 遗传学）
#基因重组 #交叉互换 #减数分裂 #遗传多样性
染色体末端的"端粒"是什么，为什么它会随年龄变短？
What is a telomere, and why does it shorten as we age?
端粒是染色体末端的重复DNA序列（人类为TTAGGG重复），像保护帽一样防止染色体末端融合或被误判为断裂。由于DNA复制存在"末端复制问题"，线性染色体每复制一次末端就丢失一小段，因此端粒随细胞分裂逐渐缩短，与细胞衰老密切相关。
A telomere is the repetitive DNA cap (TTAGGG repeats in humans) at chromosome ends that prevents them from fusing or being mistaken for breaks. Because of the "end-replication problem," a tiny piece of the linear chromosome is lost with each division, so telomeres shorten as cells divide and are closely tied to cellular aging.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
Alberts 等，《细胞的分子生物学》（第6版，Garland Science，2014）
Alberts et al., Molecular Biology of the Cell (6th ed., Garland Science, 2014)
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL7938488W：Molecular Biology of th
#端粒 #端粒酶 #细胞衰老 #染色体
一因多效指什么现象？
What is pleiotropy?
一个基因影响多个看似无关的表型称为一因多效，例如镰刀型红细胞基因既改变血红蛋白又影响对疟疾的抗性，体现了基因产物的多重生理作用。
Pleiotropy is when one gene affects multiple apparently unrelated traits—for example the sickle-cell allele alters hemoglobin yet also confers malaria resistance, reflecting a gene product's multiple physiological roles.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#一因多效 #基因 #表型
亲子鉴定靠什么判断血缘？
What does paternity testing rely on?
亲子鉴定比较孩子与疑似父亲的DNA片段，孩子的每一段都应能在父母一方找到来源，匹配度可确认血缘。
Paternity tests compare the child's DNA segments with the suspected father's; each segment should trace to one parent, and the match confirms kinship.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#亲子鉴定 #DNA #血缘
染色体不分离会导致哪些常见的染色体数目异常？
What common chromosomal number abnormalities result from non-disjunction?
减数分裂中同源染色体或姐妹染色单体未能正常分离会造成非整倍体，例如 21 三体导致唐氏综合征、X 染色体数目异常导致特纳或克兰费尔特综合征。
Failure of homologous chromosomes or sister chromatids to separate in meiosis produces aneuploidy, such as trisomy 21 causing Down syndrome or X-chromosome number anomalies causing Turner or Klinefelter syndromes.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《医学遗传学》教材
Thompson & Thompson Genetics in Medicine
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787117100816（豆瓣书目条目: 医学遗传学）
#不分离 #非整倍体 #染色体
为什么红绿色盲在男性中更常见？
Why is red-green color blindness more common in males?
控制红绿色觉的基因位于 X 染色体上，属于 X 连锁隐性遗传。男性只有一条 X 染色体，只要该基因发生隐性突变就会表现色盲；女性有两条 X 染色体，需要两条都突变才会患病，因此男性患病率明显高于女性。
The genes for red-green color vision sit on the X chromosome and follow X-linked recessive inheritance. Males have only one X chromosome, so a single recessive mutation causes color blindness, whereas females need mutations on both X chromosomes, making the condition far more common in males.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《遗传学》
Genetics: A Conceptual Approach (Pierce)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040351590（豆瓣书目条目: 遗传学）
#伴性遗传 #X连锁 #红绿色盲 #隐性
转座子（跳跃基因）是什么？
What are transposons ('jumping genes')?
转座子是能在基因组内改变位置的 DNA 片段，可造成突变与基因重排，是基因组演化的重要动力。McClintock 在 1948 年于玉米中首次发现并在 1983 年获诺贝尔奖。
Transposons are DNA segments that change position within the genome, causing mutations and rearrangements and driving genomic evolution. McClintock first found them in maize in 1948 and won the 1983 Nobel Prize.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-03
来源 · Source
McClintock 1948 年论文（1983 诺奖）；Alberts《细胞的分子生物学》
McClintock (1948, Nobel 1983); Alberts, Molecular Biology of the Cell
独立核验依据 · Independent verification: 核验依据 1 OPENLIBRARY 标识 /works/OL7938488W：Molecular Biology of th
#转座子 #跳跃基因 #基因组演化
基因是怎么“指挥”细胞制造蛋白质的？转录和翻译分别是什么？
How does a gene "instruct" a cell to build a protein? What are transcription and translation?
中心法则说遗传信息从 DNA 流向 RNA 再流向蛋白质。第一步叫转录：RNA 聚合酶把基因的 DNA 序列抄写成一条信使 RNA（mRNA）。第二步叫翻译：mRNA 进入细胞质，核糖体按每三个碱基一个“密码子”读码，转运 RNA（tRNA）把对应的氨基酸逐个带来，连成一条氨基酸链，再折叠成有功能的蛋白质。
The central dogma states that information flows from DNA to RNA to protein. The first step, transcription, uses RNA polymerase to copy a gene's DNA sequence into messenger RNA (mRNA). The second step, translation, happens in the cytoplasm: the ribosome reads the mRNA three bases at a time as a codon, while transfer RNA (tRNA) delivers the matching amino acids one by one, linking them into a chain that folds into a working protein.
难度 进阶 · 适合 大众
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。
Khan Academy（基因表达）
Khan Academy (gene expression)
#中心法则 #转录 #翻译
线粒体 DNA 的母系遗传是如何形成的？
How does maternal inheritance of mitochondrial DNA arise?
受精时精子几乎不贡献细胞质，受精卵的线粒体几乎全部来自卵细胞，因此线粒体 DNA 沿母系传递，可用于追踪母系谱系和进化历史。
At fertilization the sperm contributes essentially no cytoplasm, so the zygote's mitochondria come almost entirely from the egg, making mitochondrial DNA maternally inherited and useful for tracing maternal lineages and evolutionary history.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《进化生物学》教材
Molecular Evolution (Page)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040366723（豆瓣书目条目: 进化生物学-第3版）
#线粒体 #母系遗传 #谱系
DNA 突变是怎么发生的？突变一定有害吗？
How do mutations in DNA happen, and are they always harmful?
突变是 DNA 碱基序列的改变，来源主要有三种：DNA 复制时的偶然抄写错误、紫外线或化学物质等造成的损伤、以及移动基因片段的插入。绝大多数突变是中性的，既不好也不坏；只有少数是有害或有益的。有益的突变让生物获得新本领，成为演化的原材料，而遗传病的根源往往就是致病突变。
A mutation is a change in the DNA sequence. It can come from copying errors during DNA replication, from damage caused by UV light or chemicals, or from insertion of mobile genetic elements. Most mutations are neutral, neither good nor bad, and only a few are harmful or helpful. Beneficial mutations can give organisms new abilities and serve as the raw material of evolution, while disease-causing mutations are often behind inherited disorders.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#突变 #DNA损伤 #演化原材料
基因连锁与交叉互换如何共同决定性状的遗传模式？
How do gene linkage and crossing over together determine inheritance patterns?
位于同一染色体上且距离较近的基因倾向于连锁遗传，重组率随基因间距离增大而升高；交叉互换在减数分裂中产生重组配子，使连锁基因偶尔分离。
Genes close on the same chromosome tend to be inherited together (linkage), with recombination frequency rising as distance increases; crossing over in meiosis creates recombinant gametes that occasionally separate linked genes.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#连锁 #重组 #减数分裂
孟德尔的遗传定律包含哪些核心内容？
What are the core principles of Mendel's laws of inheritance?
孟德尔通过豌豆杂交实验提出分离定律和自由组合定律：控制性状的“遗传因子”（基因）成对存在，形成配子时彼此分离，不同性状的遗传相互独立。这些定律发表于 1866 年，奠定了经典遗传学的基础。
Through pea-plant crosses, Mendel formulated the law of segregation and the law of independent assortment: hereditary “factors” (genes) exist in pairs, separate during gamete formation, and different traits are inherited independently. Published in 1866, these laws founded classical genetics.
难度 进阶 · 适合 小学高段(9-12)
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。
孟德尔 1866 年论文《植物杂交实验》（Versuche über Pflanzen-Hybriden，布尔诺自然史学会会刊）；美国遗传学会（GSA）孟德尔遗传学教育页
Mendel (1866), 'Experiments on Plant Hybridization' (Versuche über Pflanzen-Hybriden, Verhandlungen des naturforschenden Vereines in Brünn); Genetics Society of America (GSA), Mendel and Mendelian Genetics education
#孟德尔 #分离定律 #自由组合定律
抗虫转基因作物（如Bt棉花）是怎样杀虫的？
How do insect-resistant transgenic crops such as Bt cotton kill pests?
Bt作物转入苏云金芽孢杆菌（Bacillus thuringiensis）的杀虫晶体蛋白（Cry）基因，在植物体内表达Cry蛋白。鳞翅目等害虫取食后，Cry蛋白在昆虫碱性的中肠环境中被蛋白酶活化，与中肠上皮细胞膜上的受体结合并聚合插入膜内形成孔道，破坏肠道结构使昆虫死亡。Cry蛋白对特定昆虫类群有选择性，人类和哺乳动物的肠道环境与受体差异使其相对安全；生产中常设置庇护所延缓害虫产生抗性的速度。
Bt crops carry a gene from the soil bacterium Bacillus thuringiensis encoding an insecticidal crystal (Cry) protein expressed in plant tissues. When lepidopteran pests feed, the Cry protein is activated by proteases in the alkaline insect midgut, binds receptors on the midgut epithelial cells, and polymerizes into pores in the membrane, destroying the gut and killing the insect. Cry proteins are selective for certain insect groups; mammalian gut conditions and receptors differ, so they are relatively safe, and refuges of non-Bt plants are planted to slow the evolution of pest resistance.
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。
中国科学院（Bt抗虫作物研究）
Nature Biotechnology, Bt crops and pest resistance
#Bt作物 #Cry蛋白 #转基因
人类有多少条染色体？
How many chromosomes do humans have?
正常人类体细胞含有 46 条染色体，即 23 对，其中 22 对为常染色体，1 对为性染色体（XX 为女性，XY 为男性）。生殖细胞（精子和卵子）经过减数分裂只含 23 条，受精后恢复为 46 条。
A normal human somatic cell contains 46 chromosomes, or 23 pairs: 22 pairs of autosomes and one pair of sex chromosomes (XX in females, XY in males). Gametes produced by meiosis carry only 23 chromosomes, which are restored to 46 at fertilization.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#染色体 #23对 #性染色体 #减数分裂
限制性内切酶在分子克隆中有什么用途？
What is the use of restriction enzymes in molecular cloning?
限制性内切酶能识别DNA上特定的（常为回文）序列并切割磷酸二酯键，如EcoRI识别GAATTC、切出黏性末端，BamHI等切出4碱基突出末端，SmaI则切出平末端。用同一种（或相容）酶切割质粒载体和目的DNA后，二者可通过互补黏性末端退火并用DNA连接酶连接，从而把目的基因插入质粒，是重组DNA技术的核心步骤。这类酶是细菌限制-修饰系统的防御工具，人类据此开发了基因工程。
Restriction enzymes recognize specific (often palindromic) DNA sequences and cleave phosphodiester bonds: EcoRI recognizes GAATTC and leaves sticky ends, BamHI leaves 4-base overhangs, and SmaI cuts blunt ends. Cutting a plasmid vector and insert DNA with the same (or compatible) enzyme produces complementary ends that anneal and are sealed by DNA ligase, inserting the gene of interest into the plasmid, a core step of recombinant DNA technology. These enzymes are the bacterial restriction-modification defense system, which humans repurposed for genetic engineering.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#限制性内切酶 #黏性末端 #重组DNA
为什么孩子既像爸爸又像妈妈？
Why does a child resemble both the father and the mother?
孩子从父母各得到一半染色体，所以同时继承了双方的基因组合，表现出双方特征。
A child inherits half its chromosomes from each parent, so it combines both parents' genes and shows traits of both.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#遗传 #染色体 #性状
基因突变有哪些主要类型？
What are the main types of gene mutations?
常见的突变包括点突变（单个碱基替换）、插入与缺失（碱基增减，常引起移码）、以及拷贝数变异等。突变可能由复制错误、紫外线或化学物质引发，有些无害，有些会改变蛋白质功能并导致疾病或进化素材。
Common mutations include point mutations (single-base substitution), insertions and deletions (which often cause frameshifts), and copy-number variations. They can arise from replication errors or agents like UV light and chemicals; some are harmless, while others alter protein function and contribute to disease or evolution.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《遗传学》
Genetics: A Conceptual Approach (Pierce)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040351590（豆瓣书目条目: 遗传学）
#突变 #点突变 #插入缺失 #移码
PCR扩增DNA的每一步骤是在什么温度下完成的？
At what temperatures are the steps of PCR performed?
PCR通过重复热循环扩增特定DNA片段：变性约94-96°C，双链DNA解开成单链模板；退火约50-65°C，两条引物分别与模板互补序列碱基配对；延伸约72°C，耐热的DNA聚合酶（如Taq酶）沿模板从引物3'端合成新链。一个循环产物翻倍，约30-40个循环可把目标片段扩增数百万倍。反应体系需含模板、一对引物、四种dNTP、Taq聚合酶和含Mg2+的缓冲液。
PCR amplifies a specific DNA segment through repeated thermal cycles: denaturation at about 94-96°C separates double-stranded DNA into single strands; annealing at 50-65°C allows the two primers to base-pair with complementary template sequences; extension at about 72°C lets a heat-stable DNA polymerase (e.g., Taq) synthesize new strands from the primer 3' ends. Each cycle doubles the product, and about 30-40 cycles amplify the target millions of fold. The reaction requires template, a primer pair, the four dNTPs, Taq polymerase, and a buffer containing Mg2+.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#PCR #引物 #Taq聚合酶
什么是克隆？
What is a clone?
克隆指由同一个祖先通过无性方式产生的遗传完全相同的一群个体或细胞。自然界中细菌分裂、植物扦插都是克隆。多莉羊则是用成体细胞核移植造就的著名动物克隆。
A clone is a group of individuals or cells produced asexually from one ancestor and genetically identical to it. Bacterial division and plant cuttings in nature are cloning. Dolly the sheep was a famous animal clone made by transferring an adult cell nucleus.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#克隆 #无性 #遗传
为什么同卵双胞胎长得几乎一样？
Why do identical twins look almost exactly alike?
同卵双胞胎由一个受精卵分裂成两个胚胎，拥有几乎完全相同的基因。
Identical twins come from one fertilized egg that splits into two embryos, so they share nearly identical genes.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-10-04
来源 · Source
Gilbert《Developmental Biology》,Sinauer Associates,2010
Gilbert S.F., Developmental Biology, Sinauer Associates, 2010
独立核验依据 · Independent verification: 核验依据 1 ISBN 9781605358246 (2013)
#双胞胎 #同卵 #基因
为什么“种瓜得瓜、种豆得豆”，可同一对父母生出的兄弟姐妹却各不相同？
Why do we say “as you sow, so you reap,” yet brothers and sisters of the same parents can look so different?
孟德尔用豌豆杂交实验发现，性状由成对的“遗传因子”（今天叫基因）控制，亲本各自只把每个基因的一个拷贝传给后代。每个孩子从父亲和母亲各随机获得一半基因，组合方式千差万别，所以同胞之间既像家人又各不相同。兄弟姐妹的差异还来自基因在形成精子、卵子时的重新洗牌以及受精的随机性。
Mendel's pea experiments showed that traits are controlled by paired hereditary “factors” (now called genes), and each parent passes on only one copy of every gene. Each child receives half of its genes from the mother and half from the father at random, so the combinations differ enormously, which is why siblings resemble each other yet are never identical. The reshuffling of genes during egg and sperm formation plus the randomness of fertilization add even more variety.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《普通生物学》(陈阅增)
General Biology (Chen Yuezeng)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040583151（豆瓣书目条目: 陈阅增普通生物学）
#孟德尔 #遗传因子 #等位基因
DNA和RNA有什么不同？
How do DNA and RNA differ?
DNA是双链、储存遗传信息的“蓝图”；RNA通常是单链，负责把信息送到核糖体并参与制造蛋白质。
DNA is double-stranded and stores genetic information; RNA is usually single-stranded and helps carry instructions to build proteins.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#DNA #RNA #核酸
多基因性状与孟德尔单基因性状有何不同？
How do polygenic traits differ from single-gene Mendelian traits?
多基因性状由多个基因座共同决定，每个基因贡献小效应并常受环境影响，表型呈连续分布，如身高和肤色，而不是简单的显隐性二元表型。
Polygenic traits are governed by many loci, each with a small additive effect and often environmental influence, producing continuous phenotypes like height or skin color rather than simple binary Mendelian outcomes.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#多基因 #数量性状 #连续变异
显性性状和隐性性状有什么区别？
What is the difference between dominant and recessive traits?
在成对等位基因中，若其中一个的效应能掩盖另一个，被表现的是显性性状，被掩盖的是隐性性状。隐性性状通常只有在两个等位基因都为隐性时才表现出来，例如单基因遗传病多在纯合隐性时出现。
Among a pair of alleles, if one masks the effect of the other, the expressed trait is dominant and the masked one is recessive. A recessive trait usually appears only when both alleles are recessive, which is why many single-gene disorders show up only in homozygotes.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《遗传学》
Genetics: A Conceptual Approach (Pierce)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040351590（豆瓣书目条目: 遗传学）
#显性 #隐性 #等位基因 #纯合
为什么有人能卷舌、有人不能？这类“有或无”的性状是怎样遗传的？
Why can some people roll their tongue while others cannot? How are such yes-or-no traits inherited?
经典的例子是卷舌：它由一个基因的两个版本（等位基因）决定，能卷舌的等位基因是显性，只要有一份就能表现。不能卷舌的人则必须从父母各获得一个隐性的“不卷舌”等位基因，即基因型是隐性纯合。所以两个都会卷舌的父母也可能生出不会卷舌的孩子，只要他们恰好各自都是“携带者”。需要说明的是，现代人群调查显示卷舌的真实遗传远比这个经典模型复杂，很可能由多个基因共同作用，这里只是教材常用的简化模型。
Tongue rolling is the classic example: one gene with two versions (alleles) decides it. The allele for rolling is dominant, so a single copy is enough to show the trait. A person who cannot roll must have inherited a recessive non-roller allele from each parent, meaning the genotype is homozygous recessive. That is why two roller parents can still have a non-roller child, if both happen to be carriers. It should be noted that population surveys show the real inheritance of tongue rolling is far more complex than this classic model, likely involving multiple genes; the single-gene version is a simplified textbook example.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《普通生物学》(陈阅增)
General Biology (Chen Yuezeng)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040583151（豆瓣书目条目: 陈阅增普通生物学）
#显性 #隐性 #携带者
移码突变与碱基替换相比为何通常危害更大？
Why are frameshift mutations generally more damaging than base substitutions?
插入或缺失非三倍数碱基会使阅读框整体偏移，导致下游全部密码子重读并常提前出现终止密码子，产生的蛋白质通常完全失活；而碱基替换往往只改变单个氨基酸。
Insertions or deletions not in multiples of three shift the reading frame, altering every downstream codon and often introducing premature stop codons so the protein is usually nonfunctional, whereas a base substitution typically changes only one amino acid.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《分子生物学》教材
Molecular Biology of the Cell (Alberts)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787030261946（豆瓣书目条目: 分子生物学）
#移码突变 #阅读框 #蛋白质
基因组印记为什么会使同一基因按亲本来源表现不同？
Why does genomic imprinting make the same gene behave differently depending on parental origin?
某些基因在配子发生期被亲本特异的甲基化标记，使来自父本或母本的等位基因一方沉默、另一方表达，因此即便序列相同，表达取决于遗传自哪一方。
Some genes acquire parent-of-origin methylation during gametogenesis so one parental allele is silenced and the other expressed; thus even with identical sequence, expression depends on whether the allele came from the mother or father.
难度 进阶 · 适合 小学高段(9-12)
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。
Annual Review of Genetics
Annual Review of Genetics
#基因组印记 #甲基化 #亲本来源
什么是DNA复制？
What is DNA replication?
DNA复制是细胞在分裂前拷贝自身遗传信息的过程，保证每个新细胞得到完整的一套DNA。双链被解开后，每条旧链作为模板合成互补的新链。这种半保留方式使复制既准确又高效。
DNA replication is the process by which a cell copies its genetic information before dividing, ensuring each new cell gets a full set of DNA. The two strands are unwound and each old strand serves as a template for a new complementary strand. This semiconservative method makes copying both accurate and efficient.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#DNA复制 #半保留 #分裂
孟德尔用豌豆实验发现了什么遗传规律？
What inheritance laws did Mendel discover with pea experiments?
孟德尔通过豌豆杂交实验总结出分离定律和自由组合定律：成对的遗传因子在形成配子时彼此分离，不同性状的遗传因子则独立分配。这奠定了现代遗传学的基础，说明性状由可分离、可传递的「遗传因子」（即基因）决定。
Through pea-crossing experiments, Mendel formulated the law of segregation and the law of independent assortment: paired hereditary factors separate when gametes form, and factors for different traits are distributed independently. This founded modern genetics by showing traits are determined by separable, heritable factors, genes.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-11-02
来源 · Source
《遗传学》
Genetics: A Conceptual Approach (Pierce)
独立核验依据 · Independent verification: 核验依据 1 ISBN 9787040351590（豆瓣书目条目: 遗传学）
#孟德尔 #分离定律 #自由组合定律 #遗传因子
血型是怎么决定的？
How is blood type determined?
血型由红细胞表面的抗原类型决定，主要受A、B、O三个等位基因控制。每个人从父母各得到一个基因，组合成A型、B型、AB型或O型。血型在输血和亲子鉴定中都很重要。
Blood type is determined by the antigens on the surface of red blood cells, mainly controlled by three alleles A, B, and O. Each person inherits one gene from each parent, combining into type A, B, AB, or O. Blood type matters for transfusion and paternity testing.
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
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#血型 #等位基因 #抗原
伴性遗传为什么在雌雄个体中表现不同？
Why does sex-linked inheritance manifest differently in males and females?
X 连锁基因在男性（XY）只有一份拷贝，隐性等位基因会直接表现，而女性（XX）需要两份隐性等位基因才会表现，因此红绿色盲等 X 连锁性状男性更常见。
X-linked genes have a single copy in males (XY) so recessive alleles are expressed directly, whereas females (XX) need two copies to show the trait, making conditions like red-green color blindness far more common in males.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#伴性遗传 #X染色体 #隐性
孟德尔的自由组合定律讲述了什么？
What does Mendel's law of independent assortment state?
位于不同染色体上的基因在形成配子时独立分配，使双杂合子产生四种比例相等的配子，导致后代出现特定的表型比例。
Genes on different chromosomes are distributed independently during gamete formation, so a dihybrid produces four equally frequent gamete types, giving characteristic offspring phenotype ratios.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#孟德尔 #自由组合 #遗传
为什么有些人天生卷发，有些人直发？
Why are some people born with curly hair and others straight?
发型的卷直主要由基因决定，也受毛囊形状和角蛋白结构影响。卷发者的毛囊截面更扁、发丝弯曲生长。环境和年龄也会让发质发生改变。
Curl or straightness is mainly set by genes, influenced by hair follicle shape and keratin structure. Curly hair comes from flatter follicles that make the strand grow bent. Environment and age can also change hair texture.
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
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#卷发 #基因 #毛囊
人类基因组计划取得了什么主要成果？
What were the main achievements of the Human Genome Project?
人类基因组计划于 2003 年完成了人类基因组全部约 30 亿个碱基对的测序，并绘制出约 2 万个蛋白质编码基因的大致图谱。这一公共数据库极大推动了医学、遗传学和进化研究。
Completed in 2003, the Human Genome Project sequenced all ~3 billion base pairs of the human genome and mapped roughly 20,000 protein-coding genes. Its public database has greatly advanced medicine, genetics, and evolutionary research.
难度 入门 · 适合 大众
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。
人类基因组计划（HGP）官方网站（genome.gov）；《自然》（Nature）2001/2003 专刊
Human Genome Project official site (genome.gov); Nature (2001/2003) special issues
#人类基因组计划 #DNA测序 #基因图谱
基因是什么？
What is a gene?
基因是DNA上携带遗传信息的片段，像说明书一样决定生物的性状。
A gene is a segment of DNA carrying hereditary instructions that determine an organism's traits.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23
来源 · Source
Lewin's Genes XII,Jones & Bartlett Learning,2018
Lewin's Genes XII, Jones & Bartlett Learning, 2018
#基因 #DNA #遗传