 Meiosis in males is called spermatogenesis ◦ Sperm cells are produced in the 2 testis in the scrotum sac. 2n n Slide 5

 Testosterone is the male sex hormone. ◦ In boys, the testosterone spike deepens the voice, causes the testicles to descend, and contributes to the development of other sex characteristics. ◦ Throughout the life of a man, his body will continue to produce testosterone, although the production rate will decline in old age.  Females also produce testosterone ◦ Helps with osteoporosis Slide 6

 Scrotum – contains testes where meiosis occurs - sperm cells are produced  Epididymis – coiled tube where sperm mature  Vas Deferens – transport tube  Seminal Vesicles – glands that secrete fluid (rich in sugar and provide energy to sperm)  Prostate Gland – below urinary bladder and secretes a fluid to help sperm move and survive  Semen – combination of sperm and fluids

 Testis are located outside of the body because cooler temperatures allow sperm to develop.  Urethra is the tube that carries sperm outside. It also carries urine from the bladder. This tube is located in the penis. Slide 7

 Meiosis in females is called oogenesis.  Egg (ova) cells are produced in the ovaries.  Estrogen & Progesterone are the female sex hormones. Only one egg develops Slide 8

 Ovaries – gamete production occurs here (egg)  Oviduct (aka fallopian tubes) – tube to transport eggs from the ovary to the uterus (this is where fertilization of the egg can occur)  Uterus – where fetus develops (thin, inner lining called the endometrium)  Cervix – lower end of the uterus which then tapers into the vagina

 Eggs travel from ovaries to tube called fallopian tube (oviduct) to become fertilized then goes to uterus.  Cervix is the lower end of the uterus.  Vagina is where the sperm enters during intercourse. Slide 9

 Begins a puberty  Monthly release of eggs.  “Normal” (average) cycle is 28 days  occurs in four stages. 1.Follicle stage – FSH (hormone)tells uterine lining to thicken. This takes days to complete 2.Ovulation – release of egg into oviduct This happens on day 14. This is when you can become pregnant. 3.Corpus leutem stage – LH (hormone) helps ready uterine lining for egg implantation 4.Menstruation – occurs if no egg is fertilized. The uterine lining breaks down and the tissue and blood are expelled. Slide 10

Slide 11

 Fertilization is the fusion of sperm and egg. ◦ This happens in the fallopian tubes (oviduct) ◦ Within 24 hours (sometimes 2-3 days just before, during & after) ovulation.  Note: Sperm can live inside the female reproductive tract for up to 72 hours. Slide 2

 The fertilized eggs becomes a zygote.  contains all the genetic information necessary  The zygote then undergoes cleavage (mitosis) for 6-10 days, then it attaches to the uterus.

The embryo attaches itself to the inside of the uterus

 The cells begin to undergo differentiation, this just means they become different from each other  The zygote can now be referred to as an embryo or an organism in an early stage of development  The embryo becomes a fetus once all the major organs have begun to form

 Zygote – immediately after fertilization/conceptio n  Embryo – multicellular, develops from zygote  Fetus – later stages of development, in humans usually the 8 week point and later in pregnancy

 After implantation, the zygote forms into an embryo.  The placenta forms connecting mother to embryo.  Amnion membrane that surrounds embryo contains fluid for protection Amniotic fluid  Umbilical Cord – blood vessels that carry nutrients to embryo from placenta. Slide 4

Placenta  Organ made up of both mother’s and embryo’s blood vessels  Place where nutrients, oxygen, and waste are exchanged  Does NOT allow mother and embryo blood to mix  The nutrients and wastes DIFFUSE between the blood vessels  Acts a filter for SOME substances (alcohol, caffeine, some viruses CAN pass through)  Umbilical cord – attaches the embryo to the placenta. Is cut away after birth and the scar becomes the naval.

 Nutrients and wastes DIFFUSE between the blood vessels  Filters for SOME substances (alcohol, caffeine, some viruses CAN pass through)  Umbilical cord – attaches the embryo to the placenta