Bio - Unit 9.1

• Until what week of development does a fetus have no obvious physical differences between males and females?


  Approximately 10 weeks
• By what week of development would the genitals of a fetus have been formed?


  17th-18th week
• Puberty


  is a process of physical changes that lead to sexual maturity
• Ovaries


  Female gonads which make and store eggs
• Fallopian tube/Oviduct


  Tube bringing eggs to the uterus
• Uterus


  Organ where a fertilized egg can grow into a baby
• gestation


  growth process from conception to birth
• Endometrium


  Rich blood vessel network to nourish the growing uterus/baby
• Myometrium


  muscular layer that supports the uterus
• Cervix


  Narrowing at top of vagina
• Vagina


  Tube connecting uterus to the outside, used for sexual intercourse and birth
• Effects of Estrogen in women:

  - Before birth, development of "Primary Sexual Characteristics"

  - At puberty, development of "Secondary Sexual Characteristics"

  - After puberty, maintains "sex drive" and involved in the menstrual cycle
• What are the "secondary sexual characteristics" in females?

  body hair, fatty deposits on hips and breasts, genital development, etc.
• Ureter


  Brings urine from kidneys
• Bladder


  Stores urine
• Urethra


  Tube carrying semen or urine out of body
• Testes


  Male gonads which make sperm
• Epididymis


  stores mature sperm
• Vas deferens


  tube carrying sperm to urethra
• Seminal Vesicles


  Add fructose to semen (give energy to sperm)
• Prostate


  Adds bicarbonate/alkali fluid to semen (to neutralize vagina)
• Testosterone


  the hormone released by the testes in males
• Effects of testosterone in men:

  - Before birth, development of "Primary Sexual Characteristics"

  - At puberty, development of "Secondary Sexual Characteristics"

  - After puberty, maintains "sex drive" and is involved with sperm production.
• What are the "secondary sexual characteristics" in males?

  body hair, lower voice, muscular development, growth of genitals, etc.
• Menstrual cycle


  a series of recurring changes that occur within the female reproductive system to make pregnancy possible.
• how long do each menstrual cycle last?

  28 days
• The menstrual cycle is controlled by the increase and decrease of four main hormones

  Follicle stimulating hormone (FSH)

  Luteinizing hormone (LH)

  Estrogen

  Progesterone
• Hormones released by the anterior pituitary (a part of the brain):

  Follicle stimulating hormone

  Luteinizing hormone
• Follicle stimulating hormone


  Makes eggs start growing
• Luteinizing hormone


  Causes ovulation and its release is triggered by high estrogen levels
• Hormones released by the ovaries:


  estrogen

  progesterone
• Estrogen


  is released by a growing follicle (a sac surrounding the egg); estrogen also grows the endometrium
• Progesterone


  released by the corpus luteum (the sac that no longer contains the egg)

  Progesterone maintains the endometrium and prevents menstruation.

  Progesterone also inhibits the release of FSH, thereby preventing eggs from growing
• Process of the Menstrual Cycle (egg not fertilized)

  1. A growing egg releases estrogen, which causes the endometrium to thicken.

  2. The brain detects high estrogen levels and causes ovulation.

  3. The ovary secretes progesterone which maintains the endometrium and, with estrogen, inhibits new egg growth

  4. Progesterone levels drop, causing the endometrium to break down and menstruation to start.

  5. No more progesterone, so cycle restarts.
• Process of the Menstrual Cycle (Egg is fertilized)

  1. A growing egg releases estrogen, which causes the endometrium to thicken.

  2. The brain detects high estrogen levels and causes ovulation.

  3. The ovary secretes progesterone which maintains the endometrium and, with estrogen, inhibits new egg growth

  4. Sperm fertilizes the egg, becoming a zygote.

  5. The zygote releases a hormone, HCG, which maintains progesterone.
• What can a female experience when going through the process of menstruation?

  fatigue, cramps, bloating, breakouts, cramps in the lower abdomen or back, sore breasts, and/or mood swings.
• toxic shock syndrome


  a bacterial infection characterized by high fever, muscle aches, and other symptoms.
• in extreme cases of TSS

  it can lead to kidney failure or death
• cause of TSS


  When tampons and menstrual cups are left inside the vagina for longer than recommended
• to avoid TSS


  tampons and menstrual cups should be changed as recommended in their instructions