What are the hormones involved in gender?

1. Pre-natal development of male sex organs Functions of Testosterone: 1. Pre-natal development of male sex organs SRY gene on the Y chromosome causes a surge of testosterone in the developing baby, causing a penis and testes to develop. If Y chromosome is present, it’s SRY gene causes testosterone surge If Y chromosome is absent, no testosterone surge occurs 6 week old embryo (has no gender yet)

2. Secondary sexual characteristics in puberty Functions of Testosterone: 2. Secondary sexual characteristics in puberty Increased muscle mass, pubic and body hair, male grows taller, voice deepens, increased aggression, sperm production begins. Testosterone released during puberty Testosterone released during puberty Testosterone released during puberty

Functions of Testosterone: 3. Sex Drive and Aggression Testosterone increases male sex drive and makes sperm production constant for his entire life. Aggression is likely an evolutionary adaptation for hunting, defense, and mate competition.

Andre the Giant was a person who suffered from acromegaly, in which the pituitary gland overproduces growth hormone (GH).

1. Pre-natal development of female sex organs Functions of Estrogen and Progesterone: 1. Pre-natal development of female sex organs If the SRY gene on the Y chromosome is absent, then estrogen and progesterone manufacture begins, and the fetus becomes a female. Low levels of estrogen and progesterone (due to the presence a Y chromosome’s SRY gene) High levels of estrogen and progesterone (due to the lack of a Y chromosome’s SRY gene) 6 week old embryo (has no gender yet)

2. Secondary sexual characteristics in puberty Functions of Estrogen and Progesterone: 2. Secondary sexual characteristics in puberty Female grows taller, development of pubic hair, voice deepens, changed distribution of body fat, development of breasts. Estrogen and Testosterone released during puberty determine Estrogen and Testosterone released during puberty Estrogen and Testosterone released during puberty

Functions of Estrogen and Progesterone: 3. Regulation of the menstrual cycle. Much more on that to come…

Biology Journal 3/31/2014 The menstrual cycle is regulated by 4 hormones. It “begins” with menstrual bleeding, and repeats about every 28 days. What could be some reasons for this bleeding? Why does it happen? Bleeding is when the uterus gets rid of the endometrium lining. This lining is what the uterus prepares to be the placenta, providing blood-borne nutrients to the baby, if the woman becomes pregnant.

Biology Journal 3/23/2014 Right before ovulation, the hormones _________, _________, and _________ reach their highest concentration. The leftover part of the follicle that released the egg, now called the corpus luteum, releases the hormone _________, which causes the build up of the lining of the _________, called the endometrium. This will be shed during _________, if a female is not _________.

Biology Journal 3/23/2014 Right before ovulation, the hormones estrogen, luteinizing hormone (LH), and follicle stimulating hormone (FSH) reach their highest concentration. The leftover part of the follicle that released the egg, now called the corpus luteum, releases the hormone progesterone which causes the build up of the lining of the uterus called the endometrium. This will be shed during the mensturation if a female is not pregnant.

The hormones _________ and _________ stimulate a follicle to develop The hormones _________ and _________ stimulate a follicle to develop. Ovulation happens when the hormones _________, _________, and _________ reach their highest concentration. After ovulation, the follicle turns into a structure called _________, which will produce the hormone _________. But, when this structure disappears, and stops making hormone, then _________ happens. If a female becomes pregnant, however, then the endometrium becomes the _________, and produces the hormone _________, so that it is not shed, which would kill the fetus.

The hormones FSH and LH stimulate a follicle to develop The hormones FSH and LH stimulate a follicle to develop. Ovulation happens when the hormones FSH, LH, and estrogen reach their highest concentration. After ovulation, the follicle turns into a structure called corpus luteum which will produce the hormone progesterone. But, when this structure disappears, and stops making hormone, then menstruation happens. If a female becomes pregnant, however, then the endometrium becomes the placenta and produces the hormone progesterone, so that it is not shed, which would kill the fetus.

What is the release of an egg (ovum) from the ovary called? Biology Journal 4/2/2014 What is the release of an egg (ovum) from the ovary called? What is the structure called that develops this egg? What hormone does it make? What does this structure turn into after releasing an egg?

What is the release of an egg (ovum) from the ovary called? Biology Journal 4/2/2014 What is the release of an egg (ovum) from the ovary called? Ovulation This is also when a female is most fertile. What is the structure called that develops this egg? Follicle Immature eggs are called oocytes. What does this structure turn into after releasing an egg? Corpus luteum This begins to make progesterone, before completely breaking down.

Biology Journal 3/20/2015 List the structures that a sperm cell passes through from spermatogenesis, to when it is released out of the penis through ejaculation. 1. Testicle, where spermatogenesis happens. 2. Epididymis the cells mature 3. Carried along vas deferens, where it passes through 2 glands… 4. Seminal vesicle adds fructose and mucus 5. Prostate adds fluids to neutralize acid in vagina 6. Urethra carries sperm through the… 7. Penis where it exits the body

What do FSH and LH make happen? Biology Journal 3/24/2015 What makes FSH and LH? The pituitary gland in the brain. What do FSH and LH make happen? They cause the formation of a follicle, and then ovulation. What makes estrogen? The follicle What makes progesterone? The corpus luteum (the follicle turns into the corpus luteum after it ovulates) What do estrogen and progesterone do? They develop and maintain the endometrium layer in the uterus. (When these hormones disappear, the endometrium dies and is released through menstruation)

Biology Journal 3/25/2015 What is IVF? How does it work? What are some arguments for and against it?

6.6 Reproduction

Review! What are the male sex cells called? Sperm, aka spermatozoa, aka male gamete Review! What are the female sex cells called? Eggs, or oova (when mature), or oocyte (when immature), aka female gamete What is a haploid cell? These have a half set of DNA (23 chromosomes in humans) What is a diploid cell? These have a full set of DNA (46 chromosomes in humans)

1 → 4 cells (not identical, half DNA) What kind of cells does mitosis make? Mitosis Mitosis starts with a body cell (diploid) and makes another identical body cell (diploid). 1 → 2 cells (identical) Review! What kind of cells does meiosis make? Meiosis Mitosis starts with a body cell (diploid) and makes 4 haploid cells that are all different. 1 → 4 cells (not identical, half DNA)

Whoa, that’s a lot of science vocabulary. Does it make sense to you? Gametes are haploid sex cells that fuse through fertilization in sexual reproduction to form a diploid embryo. Whoa, that’s a lot of science vocabulary. Does it make sense to you?

A sperm cell’s journey… Spermatogenesis in a testicle Maturation in epididymis Carried along vas deferens Fructose and mucus picked up at seminal vesicle Prostate adds fluids to neutralize acid in vagina Ejaculation through penis, through the urethra

About 250 million sperm cells are released during one male ejaculation!

Seminal Vesicle Bladder Prostate Urethra Vas Deferens Penis Epididymis Adds fructose and mucus to sperm Bladder Stores urine (not a reproductive organ) Prostate Adds fluids to neutralize acid in vagina to sperm Urethra Duct for urine or sperm Vas Deferens Sperm travels through this tube during ejaculation Penis Enters vagina to deliver sperm Epididymis Newly formed sperm mature / stored here Testicle Spermatogenesis happens here

Review! What is this kind of chart called? It’s a karyotype, a picture of all of a person’s chromosomes What can we determine about the person from this chart? We can determine that it is a male (XY sex chromosomes) and that this person has down syndrome (trisomy 21)

Uterus Oviduct (aka Fallopian Tube) Ovary Muscle Wall Cervix Holds fetus and placenta during pregnancy Oviduct (aka Fallopian Tube) Egg (or embryo, if fertilized) travels to uterus *Female reproductive organs do not share a passageway with urinary system, like it does in males. Ovary Eggs and follicles develop here Muscle Wall Contracts to push out fetus and dead endometrium Cervix Creates seal to block infections. However, sperm, menstrual fluid, and babies pass through it Endometrium Redevelops every menstrual cycle, turns into placenta during pregnancy Vagina Passageway for penis and fetus. Is acidic, to discourage infections

FSH LH Estrogen Progesterone Pituitary Hormones Stimulates oocyte (immature egg) development in ovary LH Also stimulates oocyte development. Causes ovulation (release of mature egg) These hormones are released by the pituitary gland. Hormones of Ovaries Estrogen Develops endometrium Progesterone Maintains endometrium. Stays high during pregnancy. Menstruation happens when this hormone level decreases. These hormones are released by the ovaries.

Phases of Menstrual Cycle Menstruation: endometrium (aka “menses”) breaks down and is shed. Follicular phase: a follicle in the ovary develops and release a new egg. Luteal phase: the follicle becomes the corpus luteum, which secretes progesterone, then disappears, triggering menstruation. If pregnancy happens, the placenta produces progesterone to prevent menstruation.

Menstruation

The Birth Control Pill Red pill It’s a placebo (no hormones) Menstruation happens on regular basis at this time Blue Pill It’s made with estrogen and progestin (synthetic progesterone) When these hormones are high, the pituitary gland thinks the body is pregnant, so no ovulation occurs (thus no ability to become pregnant)

Meanwhile in my uterus… Cramps! If no fertilization (and pregnancy) occurs, the endometrium needs to be shed and replaced with a new one. The endometrium breaks down as progesterone levels drop (because the corpus luteum, which makes progesterone, degenerates) The uterus muscle contracts, restricting blood flow to the endometrium, helping to kill the endometrium cells, and then keeps contracting to force them out of the cervix. Meanwhile in my uterus…

Cramps! Up to 50% of women experience menstrual cramps, with around 15% suffering from severe pain. This is known as dysmenorrhea. Type I dysmenorrhea begins in puberty. Type II begins much later and could be a sign of an internal health problem.

Seminal Vesicle Bladder Prostate Urethra Vas Deferens Penis Epididymis Adds fructose and mucus to sperm Bladder Stores urine (not a reproductive organ) Prostate Adds fluids to neutralize acid in vagina to sperm Urethra Duct for urine or sperm Vas Deferens Sperm travels through this tube during ejaculation Penis Enters vagina to deliver sperm Epididymis Newly formed sperm mature / stored here Testicle Spermatogenesis happens here

Uterus Oviduct (aka Fallopian Tube) Ovary Muscle Wall Cervix Holds fetus and placenta during pregnancy Oviduct (aka Fallopian Tube) Egg (or embryo, if fertilized) travels to uterus *Female reproductive organs do not share a passageway with urinary system, like it does in males. Ovary Eggs and follicles develop here Muscle Wall Contracts to push out fetus and dead endometrium Cervix Creates seal to block infections. However, sperm, menstrual fluid, and babies pass through it Endometrium Redevelops every menstrual cycle, turns into placenta during pregnancy Vagina Passageway for penis and fetus. Is acidic, to discourage infections

Male Female Pituitary Gland Vas Deferens Progesterone to the… to the… Sperm cells start here and travel from… Which stands for Contains a gland called the function Which makes a 2 hormones called… to the… Pituitary Gland Which stands for function These 2 hormones stimulate the ovary to make a structure that will eventually release an egg; this structure is called a to the… makes a hormone called Vas Deferens function to the… The egg is eventually released; this is called Which causes the uterus to build the function to the… The leftover follicle changes into a structure called the function which causes the uterus to maintain the to the… It makes a hormone called Progesterone function to the… If the egg is fertilized, then the endometrium becomes the If the egg is not fertilized, then there is a decrease in the level of the hormone function Ejaculation happens, and sperm first enters the female’s and then travels through the female’s cervix, uterus, and fallopian tube to find an egg which will produce the hormone This causes the endometrium to die; it will be pushed out by contractions of the and provide nutrients to the embryo for about 9 months until the uterus contracts, pushing the fetus out through the and will exit through the vagina in a process called

Male Female Brain Testicle FSH Pituitary Gland LH Epididymis Follicle Sperm cells start here and travel from… Spermatogenesis happens here Which stands for Contains a gland called the Testicle Which makes a 2 hormones called… FSH Follicle stimulating hormone function to the… Pituitary Gland Which stands for LH Luteinizing hormone Sperm matures here and is stored until ejaculation Epididymis function These 2 hormones stimulate the ovary to make a structure that will eventually release an egg; this structure is called a to the… Sperm travels through this tube during ejacultion Follicle makes a hormone called Estrogen Vas Deferens function to the… The egg is eventually released; this is called which causes the uterus to build the Adds fructose (a sugar for sperm food) and mucus (to lubricate sperm) Seminal vesicle function Ovulation Endometrium to the… Adds fluids that neutralize the acids in the vagina, to help the sperm survive Prostate The leftover follicle changes into a structure called the function which causes the uterus to maintain the to the… It makes a hormone called A duct shared between urine and sperm Corpus Luteum Progesterone Urethra function to the… If the egg is fertilized, then the endometrium becomes the If the egg is not fertilized, then there is a decrease in the level of the hormone Enters the vagina, delivering the sperm and semen Penis function Placenta Progesterone Ejaculation happens, and sperm first enters the female’s and then travels through the female’s cervix, uterus, and fallopian tube to find an egg This causes the endometrium to die; it will be pushed out by contractions of the which will produce the hormone Progesterone Uterus Vagina and provide nutrients to the embryo for about 9 months until the uterus contracts, pushing the fetus out through the and will exit through the vagina in a process called Vagina Menstruation

Male Female Brain Testicle FSH Pituitary Gland LH Epididymis Follicle Sperm cells start here and travel from… Spermatogenesis happens here Which stands for Contains a gland called the Testicle Which makes a 2 hormones called… FSH Follicle stimulating hormone function to the… Pituitary Gland Which stands for LH Luteinizing hormone Sperm matures here and is stored until ejaculation Epididymis function These 2 hormones stimulate the ovary to make a structure that will eventually release an egg; this structure is called a to the… Sperm travels through this tube during ejacultion Follicle makes a hormone called Estrogen Vas Deferens function to the… The egg is eventually released; this is called which causes the uterus to build the Adds fructose (a sugar for sperm food) and mucus (to lubricate sperm) Seminal vesicle function Ovulation Endometrium to the… Adds fluids that neutralize the acids in the vagina, to help the sperm survive Prostate The leftover follicle changes into a structure called the function which causes the uterus to maintain the to the… It makes a hormone called A duct shared between urine and sperm Corpus Luteum Progesterone Urethra function to the… If the egg is fertilized, then the endometrium becomes the If the egg is not fertilized, then there is a decrease in the level of the hormone Enters the vagina, delivering the sperm and semen Penis function Placenta Progesterone Ejaculation happens, and sperm first enters the female’s and then travels through the female’s cervix, uterus, and fallopian tube to find an egg This causes the endometrium to die; it will be pushed out by contractions of the which will produce the hormone Progesterone Uterus Vagina and provide nutrients to the embryo for about 9 months until the uterus contracts, pushing the fetus out through the and will exit through the vagina in a process called Vagina Menstruation

What is going on in the uterus at these times? Uterine walls are mostly “empty” Endometrium is building up, and up and up… Menstruation (endometrium is shed)

What is going on in the ovaries at these times? Follicle turns into corpus luteum Ovulation Follicle matures Corpus luteum disappears Follicle appears What hormone does the follicle make? Estrogen What hormone does the corpus luteum make? Progesterone

At what time is a female most fertile? Why? Right before and after ovulation a female is most fertile. It is at this time that she has released a “fresh” egg, and afterwards the egg dies. Therefore, right before and after menstruation is when she is least fertile. Most fertile!

Seminal Vesicle Bladder Prostate Urethra Vas Deferens Penis Epididymis Adds fructose and mucus to sperm Bladder Stores urine (not a reproductive organ) Prostate Adds fluids to neutralize acid in vagina to sperm Urethra Duct for urine or sperm Vas Deferens Sperm travels through this tube during ejaculation Penis Enters vagina to deliver sperm Epididymis Newly formed sperm mature / stored here Testicle Spermatogenesis happens here

Uterus Oviduct (aka Fallopian Tube) Ovary Muscle Wall Cervix Holds fetus and placenta during pregnancy Oviduct (aka Fallopian Tube) Egg (or embryo, if fertilized) travels to uterus *Female reproductive organs do not share a passageway with urinary system, like it does in males. Ovary Eggs and follicles develop here Muscle Wall Contracts to push out fetus and dead endometrium Cervix Creates seal to block infections. However, sperm, menstrual fluid, and babies pass through it Endometrium Redevelops every menstrual cycle, turns into placenta during pregnancy Vagina Passageway for penis and fetus. Is acidic, to discourage infections

Skill: Annotate diagrams of the male and female reproductive system to show names of structures and their functions. Testis – produce sperm and testosterone Scrotum – keep testis below body temperature Epididymis – store sperm until ejaculation Sperm duct – transfer sperm during ejaculation Seminal vesicle and prostate gland – secrete fluids added to sperm to make semen Urethra – transfer semen during ejaculation and urine during urination Penis – penetrate vagina for ejaculation of semen near the cervix

Skill: Annotate diagrams of the male and female reproductive system to show names of structures and their functions. Ovary – produce eggs, estrogen, and progesterone Oviduct – collect eggs at ovulation, provide a site for fertilization then move the embryo to uterus Uterus – provides the needs of the embryo and then fetus during pregnancy Cervix – protect fetus during pregnancy and then dilate to provide a birth canal Vagina – stimulate penis to cause ejaculation and provide a birth canal Vulva – protect internal parts of female reproductive system

Application: William Harvey’s investigation of sexual reproduction in deer. Nature of science: Developments in scientific research follow improvements in apparatus—William Harvey was hampered in his observational research into reproduction by lack of equipment. The microscope was invented 17 years after his death.