Reproduction:

1
Reproduction

• Definition
• Types
• Asexual 1 parent, no variety, poor survival,
  many offspring
• Binary Fission (bacteria) 1 organism splits in
  half
• Budding (Hydra, yeast) organism grows identical
  bud on its side
• Sexual 2 parents, variety, good survival, few
  offspring
• Union of 2 gametes (egg, sperm) to form a zygote
• Gonads (ovaries, testes) produce gametes
• Conjugation (Paramecium) simplest sexual
  reproduction
• Parthenogenesis (Bees) fertilization without
  sperm

2
Fertilization

• The union of egg and sperm
• Types of Fertilization
• Indirect (external) aquatic animals, poor
  survival, many eggs, example (frog)
• Direct (internal) intercourse, terrestrial
  animals, good survival, few offspring, example
  (mammals)
• Differences Between Humans and Other Mammals
• Breeding seasons (regulated by hormones)
• Animals in heat
• Humans sexually active throughout entire lifetime
• Sexuality more then having babies

3
Puberty

• Changes in the body that make it physically
  possible to reproduce
• Adolescence
• Development of sex cells (gametes)
• Secondary Sexual Characteristics
• Male body hair, voice deepening, facial hair,
  muscle development
• Female body hair, breast development, hip
  development, distribution of body fat, menstrual
  cycle

4
Reproductive System

• Essential for the species (making a copy)
• Striking differences between males and females
• Similarities (same embryonic tissue/same hormones
  but different responses)
• Male Functions
• Production of sperm cells
• Transfer sperm to female
• Production of male sex hormones (androgens)

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• Female Functions
• Production of eggs
• Reception of sperm cells from male
• Nurturing developing embryo
• Nourishing new individual (lactation)
• Production of female sex hormones
• Formation of Sex Cells
• Spermatogenesis (sperm production)
• Begins during puberty
• Continues throughout life
• Occurs in seminiferous tubules (sperm
  factories) empty into network called rete
  testis

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• 1 spermatogonia (46) FSH (anterior
  pituitary) 1 primary spermatocyte (46) 1
  stem cell Meiosis 2 secondary
  spermatocytes (46) Meiosis 4 spermatids
  (23) spermiogenesis (cytoplasm removed
  flagella added) 4 functional sperm

7

• From primary spermatocyte sperm (64-72
  days)
• Tubules epididymis
• Harm sperm formation antibiotics, tobacco, lead,
  radiation, marijuana

8

• Oogenesis (egg production)
• Begins at puberty
• Continues until menopause
• Occurs in ovaries
• 1 oogonium (46) in fetus by
• birth oogonia gone primary oocyte (46)
  Meiosis
• secondary oocyte (46) polar body (46)
  Meiosis egg (23) 3 polar bodies (23) die
  1 functional ovum (23) (non-motile much
  cytoplasm)

9
Male Anatomy

• External Reproductive Organs

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• Penis
• Delivers sperm to the female reproductive tract
  (vagina)
• Erectile Tissue filled with blood (vascular)
  during an erection
• Impotence no erection
• Foreskin
• Extra fold of skin around the penis
• Circumcision surgical removal of foreskin
• Hygienic and religious reasons
• Oil Glands
• Smegma result of bacterial growth (dark, damp,
  hot conditions)
• Scrotum
• Sac which holds the testes
• Suspended from the groin
• Falls into abdominal cavity 2 mos. before birth
• Weakness created on the abdominal wall
• Further strain causes a hernia (tear)

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• Testes
• Male gonads which produce sperm and testosterone
• 2 oval organs covered by a sheath (tight)
• Mumps (virus) attacks testes causing swelling
• Tubules (sperm factories) crushed
• Cause sterility
• Testicular Cancer 3/100,000 (15-35 yrs. old)
• Sperm
• Male gametes
• Sensitive to temperature changes
• Dartos Muscle (smooth) moves testes up and down
• Head, nucleus, mitochondria, acrosome, flagellum

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• Epididymis
• On the top of the testes 23 inches long
• Stores maturing sperm for 6 weeks
• Spermatogenesis maturing of sperm
• Chromosome number from 46 to 23 (1 immature sperm
  to 4 mature sperm)
• Continues as vas deferens
• Vas Deferens
• Tubes that transfer sperm
• Vasectomy cutting the tubes of the male
• Semen
• Fluid and sperm released by glands
• pH of 7.5

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• Seminal Vesicles
• Make fructose
• 60 of semen
• Prostate Gland
• Milky, thin alkaline solution
• Prostate Cancer Males after 50
• PSA Test
• Cowpers Gland
• Release mucus
• First released during intercourse
• Ejaculations release of semen through urethra
• Wet Dreams nocturnal emissions

14
Female Anatomy

• Internal Reproductive Organs

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• Female Reproductive Functions
• Produce ova (eggs)
• Receive the sperm
• Nurture the developing young
• Produce milk (lactation)
• Produce female sex hormones (estrogen,
  progesterone)
• Vulva
• General term for external features
• Made of glands, fat, labia majora (analogous to
  the scrotum)
• Clitoris
• Erectile tissue (analogous to the penis)
• Hymen
• Membrane over the vagina
• Unreliable indicator of virginity

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• Vagina
• 4 inch acidic canal with elastic walls (smooth
  muscles)
• Important for intercourse, birth, menstrual fluid
• Uterus
• Holds and nourishes the developing fetus
• Known as the womb size of a fist upside down
  pear
• Lower 1/3 (cervix) connects to the vagina
• Cervical Cancer 13,000 deaths per year (15-34
  yrs.) 33 die
• Pap Test sample of cervical cells tested for
  cancer
• Consists of 3 layers
• Outer Layer
• Middle Layer (myometrium) muscles for labor,
  menstrual cramps
• Inner Layer (endomedrium) glands, blood vessels
  shed monthly

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• Ovaries
• Female gonads
• Release estrogen and progesterone
• Hold follicles (immature egg capsule) 400,000
  at birth (1 matures monthly beginning at puberty)
• Ovarian Cancer 1/70 in U.S. per year
  (dangerous)
• Fallopian Tubes (Oviducts)
• Connect ovary to uterus (Cilia at ends)
• Only place where fertilization can occur (12-24
  hrs.)
• Tubal Pregnancy fertilized egg develops fails
  to move to uterus
• Ectopic Pregnancy fetus grows outside of uterus
  (miscarriage)
• Gonorrhea/Syphilis scarring of tubes
• Breasts
• Not sex organs contain mammary glands and fat
  lactation
• Breast Cancer over 50 increase among
  Caucasians
• Mammogram 5 yr. survival rate Tamoxifen
• Mastectomy removal of breast tissue

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• Pregnancy
• Gestation Period (from fertilization to birth) 9
  mos.
• Zygote embedded in wall of uterus
• Placenta sac which holds the embryo
• Membranes surround fetus (amnion, chorion)
• Amniotic Fluid acts as a cushion
• Umbilical Cord connects mother to fetus

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Birth

• H2O breaks (amniotic fluid released)
• Myometrium contracts (Labor)
• Caused by oxytocin
• Baby delivered clean nostrils and lungs
  (breathing)
• Add silver nitrate drops to eyes (kill germs)
• Release of milk contains antibodies
• First milk (watery) colostrum
• Afterbirth released (placenta)
• Embryo before 2 mos.
• Fetus after 2 mos.

20
Menstrual Cycle

• Rhythm of changes
• Fluctuating levels of sex hormones
• Changes in the uterus and ovaries
• Normal 28 day cycle
• Days 5-13
• Day 5 1st day after a females period
• Pituitary gland releases high amounts of FSH
• FSH ripens 1 egg in the ovary (moves toward
  surface)
• Estrogen released
• Day 14
• High estrogen shuts off FSH releases LH
• LH causes ovulation (release of egg from ovary)

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• Days 15-28
• Egg turns yellow (corpus luteum)
• Begins to release progesterone shuts off LH
• Fertilization occurs moves toward uterus
• No fertilization corpus luteum disintegrates
• Days 1-4
• Estrogen and progesterone levels down
• Shedding of the endometrium (cramps of the
  myometrium)
• Blood, mucus, cells (2 oz.)
• Known as a females period

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Menopause (the change)

• 2 year period (45-60)
• Decrease in the functioning of the ovaries
• Decrease in the of eggs
• Decrease in estrogen and progesterone
• Produce high levels of FSH, LH
• Dizziness
• Heart palpitations
• hot flashes
• Mood swings