Reproductive System

Reproductive System

How does that differ from mitosis?

Special type of cell division that creates 4 genetically unique haploid gametes from 1 diploid cell

Meiosis

Goals:

• Replicate chromosomes
• Crossing over
• Divide contents to create 2 genetically unique cells

Meiosis I

Goals:

• Divide contents once more to create 4 genetically unique haploid cells

Meiosis II

• GnRH

• Oxytocin (production only)

Reproductive Endocrinology: Hypothalamus

Anterior Pituitary

• FSH

• LH

• prolactin

Posterior Pituitary

• oxytocin (secretion only)

Reproductive Endocrinology: Pituitary

Ovaries

• Estrogen

• Progesterone

• Relaxin

Testes

• Testosterone

Reproductive Endocrinology: Gonads

Reproductive Endocrinology: HPG Axis

• hCG

Reproductive Endocrinology: Placenta

Chapter 16

Male Reproductive System

Anatomy of Male Reproductive System

Sperm Production - Spermatogenesis

Differentiation

Sperm stem cells are called spermatogonia

Goal: create 4 haploid sperm cells from 1 diploid stem cell through the process of meiosis

Spermatogenesis

Testosterone Production

Begins when male reaches _____________ & continues through their life

• Hypothalamus produces ______________________

• This stimulates the release of _______ & _______ from the __________________________.

• Those hormones target the testes. What is their primary action?
• LH
• FSH

• Testosterone production is regulated by ______________ feedback.

Testosterone Production

Chapter 16

Female Reproductive System

Anatomy of Female External Genitalia

Facilitates intercourse and provides a channel for childbirth as well as menstrual blood & tissue to be removed.

lower 2-3 cm of uterus. Produces mucus that changes during a woman's ocarian cycle that can either block or enhance sperm transport.

inner lining of uterus that responds to hormonal changes to prepare for embryo implantation. If implantation doesn't occur, it slughs off during menstruation.

Middle layer of uterus. Made of smooth muscle that contracts during labor.

produces, stores, matures, and releases follicles containing female gametes (ova/egg). Also produ ces estrogen & progesterone.

Finger-like projections that swell and sweep back & forth across the ovary to draw egg into fallopian tube.

end of fallopian tube closest to ovary that is fringed with fimbriae

Tubes that act as bridge b/t ovaries and uterus. Transports egg from ovaries to uterus.

Supports the development of embryo/fetus

Anatomy of Female Reproductive Organs

Female Reproductive Anatomy -Sagittal Section

Egg Production -> Oogenesis

Goal: generate 1 haploid ovum (and polar bodies) from 1 diploid stem cell

• Ova stem cells are _____________________

• Before birth, oogonium divide to create millions of daughter cells called ________________________

• These will begin the process of meiosis I (stay arrested at prophase I)

• From puberty to menopause, 1 primary oocyte will complete meiosis I each month to form a ___________________________________.
• The secondary oocyte is what will be _____________.
• Meiosis II completes shortly after ____________________.

Oogenesis

Ovarian Cycle

The process by which ovarian follicles mature, rupture (ovulate), and degenerate. Begins when the female reaches puberty -> hypothalamus secretes __________ which drives the production of FSH and LH. 3 Phases of the Ovarian Cycle

1. Follicular phase
2. Ovulation
3. Luteal phase

Ovarian Cycle

• During the ______________ phase (~ days 0-13), FSH and LH remain relatively low.

• Just before ______________(~days 13-14), FSH and LH will spike.
• FSH causes the follicle containing the oocyte to ____________________.
• LH causes the follicle to ____________________ and release the ____________________. This process is called _______________________.

• During the _________________ phase (~days 15-28), LH and FSH return to low levels. The _____________________________ develops during this phase.

Regulation of Ovarian Cycle by FSH and LH

• During the _________________ phase (~days 0-13), the follicle containing an oocyte is growing and maturing. As it grows, it produces _________________________.

• Following ovulation, the tissue that remains of the follicle will form a new structure called the ________________________________________. This structure produces a large amount of ________________________ and some ________________________.

Estrogen & Progesterone Production

After about 2 weeks, the corpus luteum degenerates further and becomes the corpus albicans which is essentially a scar formed on the ovary from ovulation

After ovulation, the remaining tissue of the follicle becomes the corpus luteum. This structure secretes high levels of progesterone which helps maintain the lining of the uterus to prepare for implantation. The corpus luteum degenerates if implantation does not occur, but will remain for about 12 weeks if implantation does occur.

mature egg that has ruptured out of it's follicle ithin the ovary (ovulation) due to a peak in LH. This egg will remain in Metaphase II until shortly after fertilization.

At puberty, each month during the follicular phase, 1 follicle will begin maturing due to rising FSH levels. Within the maturing follicle is an egg (oocyte) that is also maturing and continuing through the process of meiosis (development stops at Metaphase II). As the follicle matures, it secretes estrogen.

Immature follicles - egg is paused in Prophase I. You're born with about 1 million primordial follicles and will not produce any more after birth.

Development of Ovarian Follicle

Uterine (Menstrual) Cycle

Changes that occur in the uterus during the ovarian cycle. Driven by 2 hormones: __________________ & _____________ 3 Major Phases

1. Menstrual phase
2. Proliferative phase
3. Secretory Phase

Uterine (Menstrual) Cycle

• The first phase is called the ___________________ phase (days ~0-5). During this phase, estrogen and progesterone levels are _________________ which causes the __________________ to shed (a process called ______________________________)

• The second phase is called the ____________________ phase (days ~5-14). Increasing ____________________ causes the endometrium to _____________________.

• The third phase is called the ____________________ phase (~days 14-28). Increasing progesterone & estrogen keep the endometrium ________________ and cause glands in the endometrium to secrete ______________________ to prepare for possible implantation of a fertilized egg.

Uterine (Menstrual) Cycle

Childbirth Disorders of the Reproductive System

Part II

• Videos to watch
• The Great Sperm Race
• Childbirth, Explained
• Cesarean delivery
• Vaginal delivery

Pregnancy & Embryonic Development

Disorders of the Reproductive System

• Inflammation of prostate gland
• Usually caused by cancer or infection
• Treatment depends on the cause
• Main symptom - difficulty urinating

Prostatitis

• Testicle twists and cuts off blood supply
• Sometimes occurs after injury or vigorous exercise; usually happens spontaneously in teenagers
• Main symptom: severe pain
• This is a medical emergency that requires surgery

Testicular Torsion

• Prolonged erection (>4 hours); usually without arousal
• Some meds (erectile dysfunction meds, antidepressants) can make you more susceptible
• Treatment: remove blood -> vasoconstrictors, needle aspiration, larger surgery
• This is a medical emergency that must be treated before tissue death occurs

Priapism

• Hormonal imbalance (increased androgens like testosterone)
• Characterized by enlarged ovaries with many cysts
• Often also causes insulin resistance - those affected need to manage blood glucose
• Symptoms: pain, irregular menses, irregular ovulation, infertility
• Treatment: manage blood sugar, birth control pills, fertility meds

Polycystic Ovarian Syndrome

• Treatment: surgical removal of lesions, birth control pills, GnRH antagonists

• Endometrium grows outside of uterus
• it responds to estrogen and progesterone - thickens and sheds
• Causes scar tissue/adhesions to develop
• Symptoms: severe pain, heavy menses, infertility

Endometriosis

• Pregnancy that occurs outside of the uterus -> usually the fallopian tube
• This is a medical emergency - requires medical attention (termination of pregnancy with meds or surgery) immediately. No treatment = hemorrhage and death

Ectopic Pregnancy

Sexually Transmitted Infections (STI's)

• AKA "the clap"
• Caused by a bacterial infection (Neisseria gonorrheae) spread from sexual contact
• Signs/Symptoms:
• Thick yellowish discharge from penis/vagina; tingling
• Can also cause throat infections (if contracted via oral sex)
• Treatment: antibiotics

Gonorrhea

• Caused by a bacterial infection (Trepenoma pallidum) spread through sexual contact
• Signs/Symptoms:
• development of chancre -> painless ulcer where bacteria entered
• Eventual body-wide rash that comes and goes
• Brain damage and death if not treated
• Treatment: antibiotics

Syphilis

• Caused by a bacterial infection (Chalmydia trachomatis) spread through sexual contact
• Signs/Symptoms:
• Large amount of light-colored discharge
• Often no other symptoms (silent disease). Sometimes will experience burning
• Treatment: antibiotics

Chlamydia

• Viral infection spread through sexual contact.

• Many different strains cause different symptoms:
• warts
• cervical, penile, anal, and throat cancer

• Treatment - removal of warts/lesions. Treatment of cancer if it develops. No specific cure.

• Prevention - in addition to safe sex, Guardasil vaccine.

Human Papillomavirus (HPV)

Human Immunodeficiency Virus (HIV)

• This virus attacks T-cells (a type of immune cell)
• The photo you see is of a T-cell rupturing from an infection with HIV
• Leaves the person extremely susceptible to other infections
• If uncontrolled, can develop into AIDS (acquired immunodeficiency syndrome) -> severe immune deficiency which makes even minor infections potentially deadly.
• Treatent - antiretroviral therapy (helps, but cannot cure)

Human Immunodeficiency Virus (HIV) Aquired Immunodeficiency Disease (AIDS)

Herpes Simplex Virus (HSV) Two types exist

• Type 1 - usually causes blisters around mouth (oral herpes)
• Type 2 - usually causes blisters around genitalia (genital herpes)
• Treatment - valtrex and acyclovir (helps, but cannot cure)

Herpes Simplex Virus (HSV)

• Trichomoniasis
• Causes by a protozoan infection
• Protozoa are microorganisms that are neither bacteria, viruses, nor fungi
• Characterized by frothy green discharge with a foul fish-y odor
• Treatment - metronidazole (cures the infection)

• Trichomoniasis

Protozoan STDs

• If left untreated, many sexually transmitted diseases/infections can render you infertile.
• Photo on left - extreme PID (pelvic inflammatory disease) caused by prolonged STD
• Photo on right - epididymitis - inflammation of epididymis caused by prolonged STD

STDs and Infertility

Cervix

lower 2-3 cm of uterus. Produces mucus that changes during a woman's ocarian cycle that can either block or enhance sperm transport.

Primordial follicle

Immature follicles - egg is paused in Prophase I. You're born with about 1 million primordial follicles and will not produce any more after birth.

Infundubiulum

end of fallopian tube closest to ovary that is fringed with fimbriae

Ovum

mature egg that has ruptured out of it's follicle ithin the ovary (ovulation) due to a peak in LH. This egg will remain in Metaphase II until shortly after fertilization.

Fallopian Tubes

Tubes that act as bridge b/t ovaries and uterus. Transports egg from ovaries to uterus.

Ovary

produces, stores, matures, and releases follicles containing female gametes (ova/egg). Also produ ces estrogen & progesterone.

Endometrium

inner lining of uterus that responds to hormonal changes to prepare for embryo implantation. If implantation doesn't occur, it slughs off during menstruation.

Corpus albicans

After about 2 weeks, the corpus luteum degenerates further and becomes the corpus albicans which is essentially a scar formed on the ovary from ovulation

Corpus Luteum

After ovulation (during the luteal phase) the remaining tissue of the follicle becomes the corpus luteum. This structure secretes high levels of progesterone which helps maintain the lining of the uterus to prepare for implantation. The corpus luteum degenerates if implantation does not occur, but will remain for about 12 weeks if implantation does occur.

Fimbriae

Finger-like projections that swell and sweep back & forth across the ovary to draw egg into fallopian tube

Myometrium

Middle layer of uterus. Made of smooth muscle that contracts during labor.

Vagina

Facilitates intercourse and provides a channel for childbirth as well as menstrual blood & tissue to be removed.

Uterus

• Supports the development of embryo/fetus