什么是减数分裂，它为什么重要？
What is meiosis, and why is it important?
减数分裂产生染色体减半的精子和卵子，受精后恢复原数，既保证染色体稳定又制造遗传多样性。
Meiosis makes sperm and eggs with half the chromosomes; fertilization restores the number, keeping chromosomes stable while creating genetic diversity.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#减数分裂 #染色体 #多样性
什么是孤雌生殖？
What is parthenogenesis?
孤雌生殖的要害不是没有父亲，而是卵子在精子未进入时被激活，启动了本来要靠受精才触发的分裂程序，染色体数目再由减数分裂产物的退回或相互融合补回二倍体。后代基因只出自单一母本，省了求偶开销，蚜虫、竹节虫以及部分蜥蜴和鲨鱼都走这条路。别把它当克隆：补回二倍体的方式决定子女是否相同，重组仍会让同母的子女有差异。
The crux of parthenogenesis is not the absence of a father but the activation of an egg without sperm entering it, switching on the division programme that fertilization would normally trigger, with the chromosome number restored to diploid by retaining or fusing the products of meiosis. The young carry genes from one mother only and skip the cost of courtship, which is why aphids, stick insects and some lizards and sharks take this route. Do not mistake it for cloning: how diploidy is restored decides whether the offspring are alike, and recombination still makes the young of one mother differ.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#孤雌生殖 #卵子 #无受精
什么是克隆，它和正常繁殖有何不同？
What is cloning, and how does it differ from normal reproduction?
克隆是用一个体细胞的核培育出基因完全相同的个体，不经过两性生殖细胞的结合，因此无遗传重组。
Cloning grows a genetically identical individual from one cell's nucleus without combining sperm and egg, so there's no genetic recombination.
难度 专业 · 适合 高中(15-18)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#克隆 #核移植 #无性
女性月经周期受哪些激素调控？
Which hormones regulate the female menstrual cycle?
下丘脑的GnRH驱动垂体释放FSH和LH，调控卵泡发育与排卵；卵巢分泌的雌激素和孕酮则准备并维持子宫内膜的周期性变化。
Hypothalamic GnRH drives pituitary FSH and LH, controlling follicle growth and ovulation; ovarian estrogen and progesterone then build and maintain the uterine lining cyclically.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#月经周期 #雌激素 #排卵
有些植物从不用开花结果，也能“生孩子”长出新植株，这叫什么？
Some plants never flower or make seeds yet still “have babies”—what's this called?
这叫无性繁殖（营养繁殖）。比如马铃薯用块茎、草莓用匍匐茎、柳树插枝生根，都是母体直接长出遗传相同的新个体，不用雌雄配子结合。
It's asexual (vegetative) reproduction. Potatoes use tubers, strawberries runners, willows cuttings—the parent grows genetically identical offspring without egg-and-sperm fusion.
难度 进阶 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#无性繁殖 #营养繁殖 #块茎
什么是卵生和胎生？
What are oviparity and viviparity?
卵生动物把蛋产到体外孵化（如鸟、鸡）；胎生动物在母体内发育成幼体后直接生出（如人、猫）。
Oviparous animals lay eggs that hatch outside (birds, chickens); viviparous animals develop inside the mother and are born live (humans, cats).
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#卵生 #胎生 #发育
植物没有脚，怎么传粉？
Plants can't walk—how do they get pollinated?
植物靠风、昆虫、鸟或水把花粉带到另一朵花上，完成受精并结出种子。
Plants rely on wind, insects, birds, or water to carry pollen to another flower, achieving fertilization and seeds.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#传粉 #风媒 #虫媒
为什么后代通常和父母既相似又有差异？
Why are offspring both similar to and different from their parents?
遗传让后代继承父母特征，而基因重组和突变又带来新组合，所以相似中带着差异。
Inheritance passes on parental traits, while genetic recombination and mutation create new combinations, so offspring are similar yet varied.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#遗传 #变异 #重组
什么是无性繁殖？
What is asexual reproduction?
无性繁殖由一个个体直接产生后代，不需要两性结合，如细菌分裂、马铃薯用块茎发芽。
Asexual reproduction produces offspring from one parent without mating, e.g. bacterial division or a potato sprouting from a tuber.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#无性繁殖 #分裂 #克隆
蚜虫在夏天常常不交配就直接生出小蚜虫，这是怎么回事，雌虫不需要雄虫吗？
Aphids in summer often birth live young without mating—how, and don't females need males?
这是孤雌生殖：雌蚜能直接产出与自身基因相同的克隆宝宝，无需受精，繁殖极快，趁食物丰富时爆发性增长；到秋天天短、条件差时才转为有性生殖、产卵越冬。
It's parthenogenesis: females produce clone offspring without fertilization, multiplying explosively when food is plentiful; in autumn with short days they switch to sexual reproduction and lay overwintering eggs.
难度 进阶 · 适合 小学高段(9-12)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#蚜虫 #孤雌生殖 #克隆
试管婴儿是怎么来的？
How is a test-tube baby made?
试管婴儿在体外让精子和卵子结合成胚胎，再把早期胚胎放回母亲子宫内继续发育。
In IVF, sperm and egg are joined outside the body to form an embryo, which is then placed in the mother's womb to develop.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#试管婴儿 #体外受精 #胚胎
双胞胎一定长得一样吗？
Do twins always look alike?
不一定。同卵双胞胎基因相同、长得极像；异卵双胞胎来自两个受精卵，和普通兄弟姐妹一样有差异。
Not always. Identical twins share genes and look alike; fraternal twins come from two eggs and differ like any siblings.
难度 进阶 · 适合 初中(12-15)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#双胞胎 #同卵 #异卵
宝宝是怎样开始的？
How does a baby begin?
当爸爸的精子和妈妈的卵子结合成受精卵，就开始了一个新生命的发育。
When a father's sperm joins a mother's egg to form a fertilized cell, a new life's development begins.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#受精 #精子 #卵子
种子宝宝住在哪里长大？
Where does a seed baby grow up?
种子落在土里，喝到水、晒到太阳，就会发芽长出根和叶子，慢慢变成小植物。
A seed falls into soil, drinks water, and gets sunlight, then sprouts roots and leaves to become a small plant.
难度 入门 · 适合 小学低段(6-8)
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#种子 #发芽 #土里
受精是怎样发生的？
How does fertilization happen?
精子与卵子在输卵管相遇，一个精子穿透卵子的外层使两者细胞核融合，启动胚胎发育，并阻止其他精子进入。
A sperm meets the egg in the fallopian tube; one penetrates the outer layers so their nuclei fuse, starting embryonic development and blocking other sperm.
难度 入门 · 适合 大众
CC BY 4.0 · 已核验 · Verified 2026-08-23 · 2 条独立证据
来源 · Source
Urry 等,《Campbell Biology》第11版,Pearson,2017
L. A. Urry et al., Campbell Biology, 11th ed., Pearson, 2017
独立核验依据 · Independent verification: 核验依据 2 ISBN 978-0-13-409341-3 (11th ed., Pearson)
#受精 #精子 #卵子