Joshua Chandra Shannen Guarina

-Sexual reproduction: the fusion of haploid gametes to form a diploid cell (zygote). -The egg -The sperm -Asexual reproduction: generation of new individuals without the fusion of egg and sperm -Fission -Budding -What advantage does sex provide? -Produces offspring of different genotypes/phenotypes that enhances reproductive success of parents -Most animals reproduce sexually or asexually; but some alternate between the two. -parthenogenesis: asexual reproduction in which an egg develops without it being fertilized -Hermaphroditism -Sex reversal

-External fertilization - sperm fertilizes eggs shed into the external environment -Internal fertilization – egg and sperm unite within the female’s body -Fertilization requires coordinated timing which can be mediated by environmental cues, pheromones, or courtship behavior -Internal fertilization requires behavioral interactions between males and females as well as compatible copulatory organs -Internal fertilization usually results in a small amount of offspring -It is usually accompanied by the greater protection of embryos and parental care -Reproductive systems range from undifferentiated cells in the body cavity that creates gametes to complex assemblages of male and female gonads -Although it usually occurs in a partnership, competition emerges between individuals and between gametes

-Female reproductive anatomy: -External: labia majora, labia minora, clitoris – these form the vulva -Internal: vagina is connected to the uterus, which connects to two oviducts -There are two ovaries which is stocked with follicles containing oocytes -Male reproductive anatomy: -External: scrotum and penis -Male gonads (testes) are held in the scrotum -These contain the hormone-producing cells and sperm-forming seminiferous tubules -Human sexual response: -Sexual response cycle: -Excitement -Plateau -Orgasm -Resolution -Orgasm: rhythmic, involuntary contractions of the reproductive structures

-Gametogenesis is the production of gametes -It consists of oogenesis in females and spermatogenesis in males -Sperm develops continuously -Oocyte maturation is discontinuous and cyclic -Meiosis results in one large egg that is created in oogenesis -Meiosis also results in four sperm in spermatogenesis

-Hormonal control of the male reproductive system -Androgens from the testes cause the development of primary and secondary sex characteristics in the male -Androgen secretion and sperm production are both controlled by hypothalmic and pituitary hormones -The reproductive cycles of females: -Cyclic secretion of the GnRH from the hypothalmus and of FSH and LH from the anterior pituitary orchestrate the female reproductive cycle -FSH and LH bring about changes in the ovary and uterus via estrogens and progesterone -Estradiol is produced by the developing follicle -The progesterone and estradiol is excreted by progesterone -Menstrual Cycles -Menstrual Flow Phase -Proliferative Phase -Secretory Phase

-After fertilization and meiosis occurs in the oviduct, the zygote will eventually undergo cleavage and will from there develop into blastocyst -From there the blastocyst will be implanted in the endometrium -Human pregnancy is divided into three trimesters -All majors will have begun to develop by the eight week mark -Positive feedback by prostaglandins and the hormones estradiol and oxytocin will help regulate labor -By accepting the “foreign” offspring it shows that the mother partially suppresses the immune response -Contraceptive methods may be used to prevent fertilization -Modern reproductive technologies can be used in multiple fashions -Detect problems before birth -Assist infertile couples through hormonal methods or in vitro fertilization