1. Reproduction BIO 201: Organismal S&F Dr. Tony Serino
Misericordia Univ.
Biology Dept.

2. Asexual Reproduction
Generation of new individuals without union of gametes
Budding
Fission –separation of parent into two individuals (invertebrates)
Budding –outgrowth of a new individual from an existing one (invertebrates)
Fragmentation and Regeneration –breaking body of parent into several pieces and then regrowth of each into functional organism (invertebrates)
Parthenogenesis –an unfertilized egg develops into an adult (invertebrates and vertebrates)
Fission
Parthenogenesis

3. Sexual Reproduction
Production of sex cells (gametes) that fuse to begin forming a new individual
Most animals have cyclic reproduction activity that correspond to favorable environmental conditions for raising offspring
Controlled by hormones that vary with day length, season, temperature, rainfall and.or lunar cycles

4. Sexual Pattern Variations
Hermaphroditism –an individual with functional male and female sexual anatomy. Usually encounters results in both individuals being insemintated, but in some cases an individual may mate with itself
Sex Reversal –some species living in a same sex environment can change from one sex to another (crocs, some fish, etc.); other animals switch sex to increase their chances in contributing to the next generation (some oysters)
Wrasse undergoes sex reversal

5. External Fertilization

6. Reproduction System Functions: Survival of species
Production of sex cells (gametes)
Transport the gametes toward each other
Allow gametes to meet (fertilization)
Promote the generation, maintenance and rearing of progeny

8. Gonads: undergo Meiosis to produce gametes
Meiosis (divided into Meiosis I and II)
Meiosis I
Assorts chromosomes by homologous pairs
Then separates the pairs randomly
Reduces the number of chromosomes by half; Diploid to Haploid (2n  n)
Meiosis II
Separates sister chromatids
Progeny cells now have one DNA per chromosome

9. Male Reproduction Gonads: Testis Gamete: Spermatozoa (sperm)
Duct system: to store and transport sperm from gonad to external environment
Supporting structures:
Allow sperm maturation
Allow survival of sperm in ext. environment
Deposit sperm into female vagina
Sensory functions

10. Male Reproductive Anatomy

11. Spermatogenesis

13. Male Hormones

14. Female Reproduction Gonad: Ovary Gametes: Ova Duct System:
Transport ovum from ovary to uterus
Site of fertilization;
Receive and transport sperm to ovum
Capacitate sperm
House and support fetus
Deliver fetus
Supporting Structures
Sensory and protective functions

15. Female Anatomy
(oviduct or Fallopian tube)
Vulva

16. Oogenesis *
* First polar body may not divide to form others.

17. Development of Ovum and Follicle

18. Ovulation
Secondary oocyte
Zona Pellucida
Corona Radiata

19. Oviduct (Uterine or Fallopian tube)
Ampulla
Isthmus
Functions: transportation of ovum, sperm and zygote -capacitation of sperm -site of fertilization

20. Uterus: houses and supports fetus

21. Female Hormones Hypothalamus secretes GnRH
Anterior Pituitary secretes FSH and LH
Theca cells of ovary secrete estrogens
Granulosa cells secrete inhibin
Luteal cells (modified granulosa cells) secrete progesterone

22. Ovarian and Uterine Cycles

23. Estrous Cycle
-Estrous period of sexual readiness for the female; corresponds and may trigger sexual behavior of males
-different species have different timing patterns and number of estrous cycles per season