Download - Sexual Reproduction
Sexual Reproduction
Chapter 38
I1.Sexual/Asexual Reproduction
Asexual• Exact copy• Mitosis• One parent• Constant
conditions
Sexual• Genetic variety• Meiosis = eggs &
sperm• Two parents• Changing
conditions
Asexual examples: Hydra
Buddingof
polyps
Regen-erationOf cut pieces
Amoeba asexual division
2nd amoebaNucleus
Asexual Reproduction:
Runners in strawberries
Spores in Puffball Mushrooms
Sexual Reproduction
“Joey” develops in a Pouch
Flowering Plants Sexual Reproduction
Dry PollenFor sperm
Ferns Sexual & Asexual Reproduction
Sexual & Asexual
Comparison of Egg & Sperm
Egg• Round• Floats• Food reserves• One• Ovaries• 1N haploid
Sperm• Oval• Flagella• No food reserves• Many secrete enzyme to
penetrate egg membrane• Testicles• 1N haploid
Sperm• 1/600th inch• Survives in Temperature of 93o – 97o
• 3 Parts:– Head or Cap – holds Genetic Information of Father– Body – filled with mitochondria & supplies energy– Tail – flagellum to propel and move
• 200 million sperm made every 24 hours• 750 feet of twisted tubules which contain
specialized cells that each care for about 150 sperm• Testosterone & Estrogen made exactly balanced to
develop specific sexual characteristics
February 23, 2010• Draw a sperm and label its
parts• Review Vocab #2• Notes 38.1• Inside Story page 1033
Meiosis in the Gonads
Sperm
Meiotic celldivision Egg
Gonads make gametes!
Testes makesperm
Male Reproduction • Scrotum – sac surrounding testes that
maintain temperature – muscles contract/relax– Temperature must be 3o below body for sperm
• Testes – produces sperm cells haploid (1n) produce 4
• Sperm – male gamete– Enzymes in cap or head allow sperm to penetrate
egg– Nucleus contains genetic material– Mitochondria – lots for energy to move– Flagellum – for movement
• Epidiymis – stores sperm from testes until mature• Vas Deferens – duct that carries sperm to
ejaculatory glands and urethra• Semen - fluid• Seminal Vesicles - at base of bladder that secretes
mucous like fluid to increase fructose energy• Prostate glands – underneath bladder secretes
alkaline fluid to help sperm survive & move• Bulburethral Glands – secrete clear sticky alkaline
fluid protecting sperm by neutralizing acidic environment of vagina
• Uretha – tube running from the bladder that carries urine out through the penis.
• Semen enters the urethra after a muscle closes it off from the bladder.
• Semen is ejaculated through this tube that runs the length of the penis.
Chromosomes
Sex Chromosome Y determines a Male
February 24, 2010
• List the hormones and their actions for the male and female reproductive system.
• Trace the pathway of sperm from the testes
• Notes cont….
Reproduction Hormones - PubertyHormone Produced by Function
Testosterone Testicles Male sex traits
FSH Pituitary Stimulates LH
LH Pituitary Release of egg
Estrogen Ovaries Female sex traits
Progesterone Corpus luteum Maintains Uterus lining
Gonads make gametes!
Ovaries make eggs
Female Reproductive System• Ovary – size of an almond, where eggs are
produced approximately 400/life – Egg production is before birth, goes through meiosis –
prophase 1 then rests till sexual maturity • Oviduct – tube that transports the egg to the uterus,
fertilization occurs here• Ovulation – oocytes finish meiosis the egg ruptures
the ovary & released into oviduct (1n) 1 egg, 3 polar bodies dissolve
• Fertilized egg remains in oviduct for 7 days then divides and embeds in the lining of uterus–9 months
• Unfertilized - the egg and lining of the uterus will shed called the…
• Phases of Menstrual Cycle:• 1. Flow Phase - Discard of egg & uterine lining –
lasts approximately 5 days• 2. Follicular Phase – FSH increases & another
follicle goes through meiosis II, lasts from day 6-14, LH released & Ovulation occurs around day 14 by rupturing ovary
• 3. Luteal phase – 15-28 days the corpus luteum releases progesterone & some estrogen to increase blood supply (lipids) preparing for pregnancy by thickening the endometrium lining of the uterus
February 25
• Draw the negative feedback cycle… Then describe it in words.
• PS Lab 38.1• Finish up Notes
Negative Feedback Cycle
Menstrual Cycle
Tracking Hormone LevelsDay 2 4 6 8 10 12 14 16 18 20 22 24 26 28
LH 17 17 17 17 17 46 35 20 19 18 17 16 14 13
FSH 14 14 14 13 10 8 15 8 7 7 6 6 6 7
Estrogen
4 4 5 6 10 13 13 10 9 10 11 11 11 8
Progesterone
1 1 1 1 1 1 2 4 7 12 14 14 9 3
1. Make a graph showing the changes in amounts of LH & FSH throughout the menstrual cycle. Use 2 different colors & label please.
2. Make another graph showing the levels of estrogen and progesterone.
Tracking Hormone Levels (cont)
• Analysis:• 1. Describe the pattern of each
hormone.• 2. Indicate with a dashed line how
progesterone level would look if pregnancy occurred.
Tubal ligation