3a - Human Reproduction

Amnion

羊膜 (yángmó) A protective membrane that forms a sac (amniotic sac) around the developing embryo/fetus.

Amniotic fluid

羊水 (yángshuǐ) The fluid contained within the amniotic sac that surrounds and cushions the developing embryo/fetus, protecting it from mechanical shock and providing a stable environment.

Asexual reproduction

无性生殖 (wúxìng shēngzhí) A type of reproduction involving only one parent, producing offspring that are genetically identical to the parent.

Cervix

子宫颈 (zǐgōngjǐng) The narrow, lower part of the uterus that opens into the vagina.

Copulation (Sexual Intercourse)

交配 (jiāopèi) / 性交 (xìngjiāo) The act of mating in animals, typically involving the insertion of the penis into the vagina, leading to the transfer of semen.

Corpus luteum

黄体 (huángtǐ) A temporary endocrine structure that forms from the ovarian follicle after ovulation; secretes progesterone (and some oestrogen) to maintain the uterine lining.

Differentiation

（细胞）分化 ((xìbāo) fēnhuà) The process by which unspecialized cells (like those in an early embryo) develop into cells with specific structures and functions.

Ejaculation

射精 (shèjīng) The expulsion of semen from the penis, usually during orgasm.

Embryo

胚胎 (pēitāi) The early stage of development of a multicellular organism, typically from fertilization until the major organs have formed (in humans, up to about 8 weeks).

Epididymis

附睾 (fùgāo) A coiled tube located on the back of each testis where sperm mature and are stored before ejaculation.

Fertilisation

受精 (shòujīng) The fusion of the nucleus of a male gamete (sperm) with the nucleus of a female gamete (ovum/egg) to form a zygote.

Fetus

胎儿 (tāi'ér) The later stage of development of a mammal inside the uterus, after the embryonic stage, when body structures are largely formed (in humans, from about 9 weeks after conception until birth).

Flagellum (plural: flagella)

鞭毛 (biānmáo) A long, whip-like appendage on some cells (e.g., sperm) that enables movement.

Follicle

卵泡 (luǎnpào) A small, fluid-filled sac in the ovary that contains a developing ovum (egg) and secretes oestrogen.

Follicle Stimulating Hormone (FSH)

促卵泡激素 (cùluǎnpào jīsù) / 卵泡刺激素 (luǎnpào cìjīsù) Hormone secreted by the pituitary gland that stimulates the growth and maturation of ovarian follicles in females, and sperm production in males.

Gametes

配子 (pèizǐ) Reproductive (sex) cells that fuse during fertilization to form a zygote; male gametes are sperm, female gametes are ova (eggs). They are haploid.

Gestation Period

妊娠期 (rènshēnqī) The duration of pregnancy, from fertilization (or implantation) to birth.

Implantation

着床 (zhuó chuáng) The process by which a developing embryo (blastocyst) attaches to and embeds in the lining of the uterus (endometrium).

Luteinising Hormone (LH)

黄体生成素 (huángtǐ shēngchéngsù) / 促黄体激素 (cùhuángtǐ jīsù) Hormone secreted by the pituitary gland that triggers ovulation (release of the egg) in females and stimulates the corpus luteum to produce progesterone. In males, stimulates testosterone production.

Menstrual cycle

月经周期 (yuèjīng zhōuqī) The regular monthly cycle of changes in the female reproductive system (ovaries and uterus) that prepares the body for potential pregnancy, typically lasting about 28 days.

Oestrogen

雌激素 (cíjīsù) The primary female sex hormone, produced mainly by the ovaries (and placenta during pregnancy); responsible for the development of female secondary sexual characteristics and regulating the menstrual cycle.

Oviduct (Fallopian tube)

输卵管 (shūluǎnguǎn) The tube that connects an ovary to the uterus, through which an ovum travels after ovulation; typically the site of fertilization.

Ovulation

排卵 (páiluǎn) The release of a mature ovum (egg) from an ovarian follicle in the ovary.

Ovum (plural: Ova)

卵细胞 (luǎnxìbāo) / 卵子 (luǎnzǐ) The female gamete (sex cell), typically large and non-motile, containing stored food and the female genetic material.

Penis

阴茎 (yīnjīng) The external male reproductive organ used for sexual intercourse and urination.

Period (Menstruation)

月经 (yuèjīng) / 经期 (jīngqī) The monthly shedding of the lining of the uterus (endometrium) along with blood and unfertilized egg, if pregnancy has not occurred.

Placenta

胎盘 (tāipán) A temporary organ that develops in the uterus during pregnancy, providing oxygen and nutrients to the fetus and removing waste products, via the umbilical cord. Also produces hormones.

Progesterone

黄体酮 (huángtǐtóng) / 孕酮 (yùntóng) A female sex hormone, produced mainly by the corpus luteum and placenta; prepares and maintains the uterine lining for pregnancy and inhibits further ovulation.

Prostate Gland

前列腺 (qiánlièxiàn) A gland in the male reproductive system that surrounds the urethra at the base of the bladder; contributes alkaline fluid to semen, which nourishes and protects sperm.

Puberty

青春期 (qīngchūnqī) The period of rapid physical development during which adolescents reach sexual maturity and become capable of reproduction, marked by hormonal changes and development of secondary sexual characteristics.

Secondary sexual characteristics

第二性征 (dì'èr xìngzhēng) Physical traits that develop at puberty, distinguishing males and females, but are not directly involved in reproduction (e.g., breast development in females, beard growth in males).

Semen

精液 (jīngyè) The fluid ejaculated from the penis, containing sperm cells suspended in secretions from the seminal vesicles, prostate gland, and other accessory glands.

Seminal vesicle

精囊 (jīngnáng) Glands in the male reproductive system that produce a nutrient-rich fluid (part of semen) that nourishes sperm and increases their motility.

Sexual reproduction

有性生殖 (yǒuxìng shēngzhí) A type of reproduction involving the fusion of gametes (sex cells) from two parents, resulting in offspring that are genetically different from both parents, promoting variation.

Sperm (Spermatozoon)

精子 (jīngzǐ) The male gamete (sex cell), typically small and motile (with a flagellum), containing the male genetic material.

Sperm duct (Vas deferens)

输精管 (shūjīngguǎn) Tubes that carry sperm from the epididymis in each testis to the urethra.

Testes (singular: Testis)

睾丸 (gāowán) The male gonads (reproductive organs) located in the scrotum; produce sperm and the male sex hormone testosterone.

Testosterone

睾酮 (gāotóng) / 睾丸素 (gāowánsù) The primary male sex hormone, produced mainly by the testes; responsible for the development of male reproductive tissues and secondary sexual characteristics.

Umbilical cord

脐带 (qídài) The cord-like structure connecting the fetus to the placenta; contains blood vessels (two arteries, one vein) that transport nutrients, oxygen, and waste products.

Urethra

尿道 (niàodào) The tube that carries urine from the bladder out of the body. In males, it also carries semen during ejaculation.

Uterus (Womb)

子宫 (zǐgōng) A hollow, muscular female reproductive organ where a fertilized egg implants and a fetus develops during pregnancy.

Vagina

阴道 (yīndào) A muscular tube in the female reproductive system that connects the cervix to the outside of the body; serves as the birth canal and receives the penis during sexual intercourse.

Zygote

受精卵 (shòujīngluǎn) The single diploid cell formed by the fusion of a male gamete (sperm) and a female gamete (ovum) during fertilization; the first stage of a new organism.