Chapter 46- Reproductive System

Sexual Reproduction

The generation of offspring by fusion of haploid gametes, a male sperm and female egg, to form a diploid zygote

Hermaphroditism

Each individual has both male & female reproductive systems

Fertilization

The union of egg and sperm, can be external or internal

Pheromones

Influence the physiology & behavior of individuals of the same species

Gonads

Organs that produce gametes

Cloaca

A common opening between the external environment & the digestive, excretory, and reproductive systems

Seminiferous tubules

Where sperm are produced in the testes

Scrotum

Holds the testes

From the seminiferous tubules of a testis, sperm pass into the coiled duct of the____

Epididymis

During ejaculation, sperm are propelled through the muscular____ & the ejaculatory duct, to exit the penis through the urethra

Vas Deferens

Semen

Composed of sperm plus secretions from three sets of accessory glands

Two seminal vesicles contribute____

Contribute about 60% of the total volume of semen

The prostate gland secretes its products directly into the urethra through several small ducts during____

Ejaculation

Ovaries

Each ovary contains many____, which consist of a partially developed egg, called an___

Follicles; Oocyte

The egg cell travels from the ovary to the uterus via an____

Oviduct/Fallopian Tube

Mammary Glands

Not part of the reproductive system but are important to mammalian reproduction
• Within the glands, small sacs of epithelial tissue secrete milk

Gametogenesis

The production of gametes
• Close relationship between the gonads’ structure & their function

Spermatogenesis

The formation of sperm(Continuous)

Oogenesis

The development of a mature egg(Prolonged process)

____ secreted by the hypothalamus, directs the release of____and____from the anterior pituitary
• stimulate sex hormone production by gonads

Gonadotropin-releasing hormone (GnRH); FSH (follicle-stimulating hormone) and LH (luteinizing hormone)

Androgens

Testosterone

Estrogens

Estradiol & Progesterone

FSH stimulates____, to nourish developing sperm

Sertoli cells

LH causes____to produce testosterone & other androgens, which promote spermatogenesis

Leydig Cells

Sertoli cells secrete the hormone____, which reduces FSH secretion (provides the feedback) from the anterior pituitary

Inhibin

Menstruation(Days 1–5 of the menstrual cycle)

If an embryo does not implant in the endometrium, the endometrium is shed

Follicular phase of the ovarian cycle is coordinated with the (days 6–14) of the uterine cycle

Proliferative Phase

Luteal phase of the ovarian cycle is coordinated with the____ (days 15–28) of the uterine cycle

Secretory Phase

Endometriosis

Cells of the uterine lining migrate to an abnormal, or ectopic, location

Menopause

Cessation of ovulation & menstruation

Estrous Cycles

• Endometrium is reabsorbed by the uterus

• Sexual receptivity is limited to a “heat” period called estrus

• Length & frequency of estrous cycles vary from species to species

Vasocongestion

The filling of tissue with blood

Myotonia

Increased muscle tension

Conception

Fertilization of an egg by a sperm, occurs in the oviduct

Division of cells gives rise to a____, a ball of cells with a central cavity

Blastocyst

Pregnancy/Gestation

The condition of carrying one or more embryos in the uterus

Human Chorionic Gonadotropin (hCG)

Maintains secretion of progesterone & estrogens during early pregnancy

Pregnancy tests look for which level?

HcG

Outer layer of the blastocyst, trophoblast, mingles with the endometrium & eventually forms the____

Placenta

The first trimester is the main period of____

Organogenesis

Organogenesis

Development of the body organs

Embryo is called a____

Fetus

Contraception

Deliberate prevention of pregnancy

Tubal Ligation

Ties off the oviducts

Vasectomy

Ties off the vas deferens

Morning After Pills (MAPs)

High doses of some birth control pills can be used as emergency contraception

In vitro fertilization (IVF)

Mixes eggs with sperm in culture dishes & returns the embryo to the uterus