Exam 5 Review:  Chapter 27 Sexual Intercourse & Conception

sexual intercourse = coitus - The act of sexual procreation between a man and a woman; the man's penis is inserted into the woman's vagina and excited until orgasm and ejaculation occur; physiologists divide it into several stages:  excitement, plateau, orgasmic, resolution phases in both sexes and an additional refractory period in males.

arousal - The stimulation of sexual desire by whatever combination of thoughts and actions; for purposes of reproduction, the mutual sexual stimulation by the male and female prior to sexual intercourse.

vasocongestion - In the sexual response cycle, engorgement of the blood vessels, particularly in the erectile tissue of the genital area, due to increased blood flow.
 
orgasm = climax - The third phase of sexual intercourse; the peak of arousal and sexual excitement, characterized by strong feelings of pleasure and by a series of involuntary contractions of the muscles of the genitals, rapid breathing, high blood pressure and heart rate, skin flushing, partial loss of muscular control, involuntary muscle spasms; usually accompanied by the ejaculation of semen by the male; three patterns of female orgasmic response are recognized:  a single brief and intense orgasm, multiple intense peaks, or multiple smaller peaks.

plateau - The second phase of sexual intercourse after initial excitement during which a high level of arousal may be sustained for many minutes before orgasm.

refractory period - A time interval experienced by most males after sexual intercourse during which they are unresponsive to further sexual stimulation.

resolution - The fourth phase of sexual intercourse; characterized by a rapid return to original state, but with increased relaxation and tiredness.

erection - The firm and enlarged condition of a body organ or part when the erectile tissue surrounding it becomes filled with blood, especially such a condition of the penis or clitoris; it is regulated by impulses from the ANS.

lubrication - The application of a substance to diminish friction between two surfaces; in sexual intercourse, the bulbourethral and urethral glands in males and the greater vestibular glands and the vaginal mucous glands in females secrete mucous fluid to lubricate the sex organs during sexual intercourse.

transudation - The passage of a fluid or solute through a membrane by a hydrostatic or osmotic pressure gradient.

donor insemination - A medical treatment for various types of infertility, in which a male donates a semen sample to be used, either by introduction into a female's reproductive tract or by external, artificial means, to achieve fertilization of the female's egg and implantation in the uterus to initiate a pregnancy.

fertilization - The act or process of initiating biological reproduction by insemination which achieves the union of male and female gametes to form a zygote; in the human, a secondary oocyte, once ovulated, can remain viable for 12 to 24 hours; sperm can remain fertile in the female reproductive tract for 12 to 48 hours, although some may last for 72 hours; for fertilization to take place, intercourse can take place from 72 hours before to 24 hours after ovulation.

zygote - The single diploid cell formed by the successful union of two gametes, sperm and egg, during reproduction before cleavage begins; the especially a fertilized ovum or egg.

morula - The solid sphere or globular mass of cells (blastomeres), formed by the mitotic cleavage of the fertilized ovum = egg or zygote in the first stages of embryonic development, prior to implantation in the uterine wall.

blastocyst - The modified blastula which is characteristic of placental mammals, including humans; further cleavage of the morula produces a thin walled hollow sphere, whose wall is the trophoblast, with the embryo proper being represented by a mass of cells at one side; this second stage of embryonic development must be completed before successful implantation into the uterine wall is possible.

trophoblast membrane - The external embryonic layer of epithelium which forms around the blastocyst and is the portion of the blastocyst necessary for attachment to the endometrium in order to achieve successful implantation into the uterine wall; from it, the embryonic chorion will develop.

Describe:

3. the male and female sexual response.

Male Female
(1)  Psychological, Sensory, and Behavioral Arousal.

(2)  Erection of the penis and lubrication of the urethra (controlled by parasympathetic nerve impulses) followed by Intercourse followed by Ejaculation.  Ejaculation is expulsion of semen from the male duct system, promoted by the sympathetic nerve impulses.  Ejaculation is a part of male orgasm, which also includes pleasurable sensations and increased pulse and blood pressure.

(3)  Parental Care:  Optional and Variable in the Extreme.

 (1)  Psychological, Sensory, and Behavioral Arousal.

(2)  Erection of the vulva and lubrication of the urethra and vulva and vagina (variable - depending on arousal state - controlled by parasympathetic nerve impulses) followed by Intercourse.  No ejaculation., Female orgasm, which includes vaginal area muscular contractions, pleasurable sensations and increased pulse and blood pressure (variable - depending on arousal state) promoted by the sympathetic nerve impulses. 

(3)  If fertilization and implantation occur, gestation and parturition = birth = labor and delivery follow.  Parental Care:  Rarely optional (may include lactation/nursing) but Variable in the Extreme.