The Reproductive System 1

Chapter 52The Reproductive System

You are not responsible for the more detailed descriptions of reproduction in fishes, amphibians, reptiles and birds on pages 1070 – 1072.

You are only responsible for the hormones we discuss in class

We will draw upon a few topics from Chapter 53 about fetal development

The Reproductive System 2

How do organisms reproduce?

Sexual vs Asexual

Budding

Interesting “twists” to sexual reproduction…

Parthenogenesis-- bees-- among vertebrates

Hermaphoditism-- earthworms-- many plants

Case of thelonely

KomodoDragon

(XX-males)

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Reproductive strategies have evolved toward internal fertilization and development

Why is internal fertilization better than external?

Why is internal development better than external?

Oviparity in male midwife toadCopyright © 2000 Michael Frede

Human viviparity

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What are the characteristics of the Male Reproductive System?

Anatomy

Erection

What are 1O and 2O sexual characteristics?

2O characteristicsTestosteroneAndrostenedione abuse

Contraceptioncondomvasectomy

Question

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Endocrine hormonal regulation

Pituitary hormones FSH – stimulates

spermatogenesisLH – stimulates testosterone

synthesis

Testosterone

Androstenedione abuse

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What are the characteristics of the Female Reproductive System?

Anatomy

Pathway of egg travel

Pregnancy

Contraception:diaphragmtubal ligationspermicidesIUD

Question

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Hormonal control the female reproductive system

All mammals have periods of estrus

What is the ovarian cycle?Follicle stimulating hormone (FSH)Luteinizing hormone (LH)Follicle & corpus luteum

What is the uterine cycle?Estrogen & Progesterone

Endometrium & Menstration

Other forms of contraception Rhythm method Chemical contraceptives

oral: (The “Pill’) Implant (“Norplant”)

Injectable

Question

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What happens after fertilization?

Completion of meiosis

Implantation in endometrium

Ectopic pregnancy

Review Question

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Hormonal changes upon pregnancy

Roles of embryo and corpus luteumProgesteroneEstrogenHuman Chorionic Gonadotropin (HCG)

What happens if the female reproductive cycle becomes disrupted?

Amenorrhia Menopause

Question

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Assisted pregnancy

Artificial insemination

Gamete Intrafallopian transfer

In-vitro fertilization

Gamete donation

Surrogate mothering

Pictures used with the permission of Dr. Clemens M. Grosskinsky, ORM, ColumbusReview Question

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What are the functions of the amnion and placenta?

Amniotic sac & fluid

Maternal and fetal circulatory systems

-- no connection

Exchange of nutrientsgasseswastes

Question

Chorionic villi

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What are the stages of fetal development?

Trimesters

Embryonic stage

Fetal stage

Sensitive periods

Fetal alcohol syndrome

Question

4 weeks 3 months 6 months

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How can Congenital Defects be tested for?

Amniocentesis

Chorionic villi sampling

Perform karyotype

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Labor and Birth

Fetal position-- why is ‘breach’ position bad

Uterine contractions

Dilation of cervix

Extraction of the placenta