1 / 32

Asexual Reproduction in a Sea Anemone

Asexual Reproduction in a Sea Anemone. Figure 46.1. Overview: Doubling Up for Sexual Reproduction The two earthworms in this picture are mating Each worm produces both sperm and eggs, which will fertilize And in a few weeks, new worms will hatch.

justinbryant
Télécharger la présentation

Asexual Reproduction in a Sea Anemone

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Asexual Reproduction in a Sea Anemone

  2. Figure 46.1 • Overview: Doubling Up for Sexual Reproduction • The two earthworms in this picture are mating • Each worm produces both sperm and eggs, which will fertilize • And in a few weeks, new worms will hatch

  3. Sexual Behavior in Parthenogenetic Lizards (all female); adults are haploid (a) The female on the back induces development of an egg during critical times of the hormone cycle

  4. Sex Reversal in a Sequential Hermaphrodite Females (yellow) Male (Blue) All are born female and the largest complete lives as males

  5. Figure 46.6 • Many different types of animals • Exhibit parental care to ensure survival of offspring

  6. The Release of Eggs and External Fertilization

  7. Reproductive Anatomy of a Parasitic Flatworm

  8. Reproductive Anatomy of the Human Male

  9. Reproductive Anatomy of the Human Male

  10. Seminiferous tubules (left), sperm in semen (right)

  11. Structure of a Human Sperm Cell Contains an enzyme that helps penetrate the egg

  12. Reproductive Anatomy of the Human Female

  13. Reproductive Anatomy of the Human Female

  14. Menstrual Cycle (mensis = month) - lasts approx. 28 days

  15. Follicle Phase (lasts 10-14 days) • starts when hypothalamus re- • leases GnRH that stimulates the • pituitary gland • FSH stimulates cell division in the • follicle, a layer of cells that sur- • rounds the immature egg. These • cells supply nutrients to the egg and • secrete estrogen.

  16. Hormones of the Hypothalamus and Pituitary Glands Nerve cells that release hormones into the blood

  17. Ovum Ovary Follicle

  18. Ovulation (last 3-4 days) • when a woman is most likely to get • pregnant • occurs when LH and FSH levels peak • follicle releases the egg into the • fallopian tube

  19. Oogenesis

  20. Ovulation

  21. Luteal Phase (lasts about 14 days) • After ovulation the structure is • now called the corpus luteum. • It secretes large amount of estro- • gen and progesterone to maintain • the lining of the uterus until the • egg is fertilized.

  22. Menstruation (approx 5 days) • occurs when the endometrium • starts to slough off; the lining of • the uterus and ruptured blood • vessels are discharged through • the vagina

  23. The Reproductive cycle of the Human Female

  24. Hormonal Control of the Testes

  25. Female Male Event Event Method Method Production of viable sperm Production of viable oocytes Vasectomy Combination birth control pill (or injection, patch, or vaginal ring) Ovulation Sperm transport down male duct system Abstinence Abstinence Condom Coitus interruptus (very high failure rate) Sperm deposited in vagina Capture of the oocyte by the oviduct Tubal ligation Spermicides; diaphragm; cervical cap; progestin alone (minipill, implant, or injection) Transport of oocyte in oviduct Sperm movement through female reproductive tract Meeting of sperm and oocyte in oviduct Morning-after pill (MAP) Union of sperm and egg Progestin alone Implantation of blastocyst in properly prepared endometrium Figure 46.20 Birth • Mechanisms of Some Contraceptive Methods

  26. Formation of the Zygote and Early Postfertilization Events

  27. Placental Circulation

  28. Human Fetal Development

  29. Hormonal Induction of Labor

  30. Sperm are made in the _______ _______ and mature in the _______. The function of the prostate gland is to . . . Fertilization occurs in the . . .

  31. Ovulation occurs when the levels of _____ and _____ peak. Give an example of negative feed- back using the hormones of the menstrual cycle. A woman is most likely to get pregnant at which time of the month?

  32. Describe the path of a sperm cell from where it is made to where it fertilizes the egg in a female. Hint: There are 7 structures involved.

More Related