Puberty and Human Reproduction Lecture Notes

Flashcards covering the terminology, anatomy, and hormonal mechanisms of puberty and the female reproductive system based on the lecture transcript.

Puberty

The stage of development during which a child's body physically matures into an adult body capable of sexual reproduction.

Gonadotropin-releasing hormone (GnRH)

A hormone triggered by the hypothalamus that stimulates the pituitary gland to secrete FSH and LH.

FSH (Follicle Stimulating Hormone) in Females

Secreted by the pituitary, it stimulates maturation of the ovarian follicle during the follicular phase.

LH (Luteinizing Hormone) in Females

A hormone whose surge at midcycle triggers ovulation and turns the follicle into the corpus luteum.

Thelarche

The beginning of breast development in girls during puberty, typically starting between $10\text{-}12$ years of age.

Pubarche

The growth of pubic and armpit hair in both sexes during puberty.

Menarche

The onset of menstruation in girls, which usually starts $1$ year after breasts develop.

Oestrogen

A hormone produced by the ovaries responsible for the development of all female secondary sexual characteristics.

Testosterone

A hormone produced by the testes (specifically Leydig cells) responsible for the development of all male secondary sexual characteristics.

Progesterone

A hormone produced by the corpus luteum that keeps the endometrium lining of the uterus intact to allow a blastocyst to implant.

Growth Hormone (GH)

A hormone that increases during puberty, leading to an increased growth rate.

Uterus

A hollow, pear-shaped organ where the embryo implants and the foetus develops during pregnancy.

Myometrium

The middle layer of the uterine wall consisting of smooth involuntary muscle.

Endometrium

The mucous membrane lining the inside of the uterus that thickens with blood vessels and is shed during menstruation if pregnancy does not occur.

Fallopian tube / Oviduct

Tubes extending from each ovary to the uterus where fertilisation occurs and egg cells are transported.

Cervix

The narrow entrance to the uterus that connects to the vagina and stretches open during labour and childbirth.

Vagina

The passage between the uterus and the outside of the body, consisting of a folded muscular wall.

Clitoris

A small, sensitive female erectile sexual organ located outside the body, analogous to the male penis.

Germinal epithelial cells

A layer of cuboidal cells that surrounds the ovary.

Ovarian follicles

Small fluid-filled sacs in the ovaries that contain a single oocyte and secrete oestrogen.

Oocyte

An immature ovum or egg cell.

Graafian follicle

A mature ovarian follicle that contains a mature egg cell ready for release.

Corpus luteum

The temporary endocrine structure formed from the remains of the Graafian follicle after ovulation; it produces progesterone and oestrogen.

Luteal phase

The second half of the menstrual cycle, beginning after ovulation and continuing until menstruation occurs.

HCG (Human Chorionic Gonadotropin)

A hormone from a developing embryo that sustains the corpus luteum beyond its typical $12\text{-}14$ day lifespan.

Sertoli cells

Cells in the testes stimulated by FSH to produce androgen-binding protein (ABP) and inhibin.

Leydig cells

Cells in the testes stimulated by LH to produce testosterone.

Negative Feedback

A regulatory mechanism where a hormone's action leads to a decrease in its own production to maintain homeostasis.

Inhibin

A hormone produced by Sertoli cells that provides negative feedback to the pituitary to decrease FSH secretion.

Menopause

The stage, usually around age $50$, when a woman no longer ovulates and menstruation stops.

Ovulation

The release of an ovum from a Graafian follicle in the ovary, generally occurring on day $14$ of the cycle.