BiologySylvia S. Mader
Michael Windelspecht
Chapter 41
Reproductive Systems
Modified D. Herder
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
See separate FlexArt PowerPoint slides for all figures and tables pre-inserted into
PowerPoint without notes.
1
41.1 Asexual Reproduction
• Invertebrates:• Sponges, cnidarians, flatworms, annelids, • Hydras: outgrowth (bud) of the parent• Flatworms: split in half• Sponges, annelids, & echinoderms can have the ability to regenerate from
fragments
2
Reproduction in Hydra
3
parentalpolyp
budding ofnew polyp
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Dr. Dennis Kunkel/Visuals Unlimited
Sexual Reproduction
– Most animals are dioecious
• Separate sexes
– Some are monoecious (hermaphroditic)
• Contain both male & female sex organs
• Most cross-fertilize
4
Sexual Reproduction
• Gonads
– produce gametes
– Parthenogenesis
• Unfertilized egg develops into a complete individual
5
Sexual Reproduction
– Many aquatic use external fertilization
– Internal fertilization (copulation)
6
Strategies
– Oviparous: deposit eggs in the external environment• Aquatic animals (frogs)
– Ovoviviparous retain their eggs, though do not provide direct nutrients (sea horse)
– Viviparous retain eggs and provide nutrients to them (humans)
7
• Reptiles & birds provide eggs– Oviparous– Development takes place in shelled egg containing
extraembryonic membranes– Yolk – Parents often tend eggs & young
• Placental mammals are viviparous– Do not lay eggs– Placenta –exchanges material between mother &
developing embryo– Development inside female– Care of zygote and embryo
8
Parenting in Birds
9
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Anthony Mercieca/Photo Researchers, Inc.
– Testes: paired gonads suspended in scrotum
– Sperm: produced by testes in seminiferous tubules
• Tubes packed with cells undergoing spermatogenesis
• Mature within epididymis
• Eventually enter vas deferens (ductus deferens)
– Semen: (seminal fluid) contains
• Sperm
• Secretions from
– Seminal vesicles
– Prostate gland
– Bulbourethral glands
10
Male Reproductive System
Testis and Sperm
12
interstitialcells
immaturesperm
Sertolicell
uncoiledseminiferous
tubule
lobule
testis
scrotal sac
b. Seminiferous tubules100 µm
vas deferens
epididymis
a. Testis, cut to show lobules(b): © Anatomical Travelogue/Photo Researchers, Inc.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
13
MITOSIS MEIOSISI MEIOSISII
spermatogonium(diploid)
primaryspermatocyte(diploid)
secondaryspermatocyte(haploid)
earlyspermatid(haploid)
latespermatid(haploid)
immature sperm(haploid) acrosome
head
middle piece
tail
nucleus ofSertoli cell
end piece
d. Spermc. Spermatogenesis
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Testis and Sperm
Male Reproductive System
14
Hormonal Control of the Testes
15
hypothalamus
LH
FSH
testis
GnRH
anteriorpituitary
--
-
-
++
Seminiferoustubulesproducesperm
plus inhibin.
Interstitialcells
producetestosterone.
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
41.3 Female Reproductive System
• Oocyte (egg) bursts from an ovary • Swept into oviduct • Fertilization normally occurs in the oviduct• Ciliary action moves the developing embryo to the uterus• Embryo embeds in the uterine lining (endometrium)
16
Female Reproductive System
17
oviduct
ovary
fimbriae
uterus
urinary bladder
pubic bone
urethra
glans clitoris
labium minora
labium majora
vaginal orifice
a. b.
anus
vagina
rectum
cervix
monspubis
glansclitoris
urethra
labiamajora
vagina
labiaminora
anus
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Female Reproductive Organs
18
Hormonal Control of Ovaries
19
hypothalamus
LH
FSH
estrogen progesterone
GnRH
oocyte
follicle
-/+-
-
-/+
+
anteriorpituitary
+
corpusluteum
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
Ovarian and Uterine Cycles
20
Ovarian Cycle
21
egg
sperm
MEIOSIS I MEIOSIS II
Ovarian cycle
5. Corpus luteum develops.
a.
b.
vesicular (Graafian) follicle
oocyte
2. The secondary follicle contains a secondary oocyte.
1. A primary follicle contains a primary oocyte.
primaryfollicles
secondaryfollicle
6. Corpus luteum degenerates.
corpusluteum
3. Vesicular (Graafian) follicle develops.
secondaryoocyte
4. Ovulation: Oocyte is released.
first polarbody
second polarbody
Sperm enters, andmeiosis II goesto completion.
secondary oocyte(23 chromosomes)
primary oocyte(46 chromosomes)
Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.
© Ed Reschke/Peter Arnold, Inc.
Top Related