RA Ch 19 Reproductive System PDF

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Reproductive System
Virginia Turner
summer 2020...

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Ch 19 Reproductive System 19.1 introduction  

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Reproductive systems o Connected sets of organs that produce/ nurture gametes Female sex cells o Oocytes  Egg cells Chromosomes o Made of DNA and protein – becomes visible during cell division 46 chromes Andr – man Ejacul - shoot forth Fimb- fringe Folic – small bag Genesis – origin Labi – lip Mens – month Mons – eminence Puber – adult 19.2 Organs of male reproductive system

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Primary sex organs o Gonads o 2 testes – sperm cells develop, sex hormones are synthesized Accessory sex organs o Are the internal? External reproductive organs Testes o Ovid structures – 5cm in length, 3 cm in diameter o Inside scrotum Spermatogenesis – sperm cell production Mature sperm cell is shaped like a tadpole - .06mm long o Flattened head o Cylindrical body o Elongated tail INTERNAL ACCESSORY ORGANS o Are specialized to nurture/ transport sperm cells  2 epididymis  Tightly coiled tubes  6 m long  Connected to a duct within testes

Emerges from top of testes, descends along posterior surface of the testes, courses upward and becomes ductus deferens  Sperm cells here are nonmotile o Rhythmic contractions move them – and cells become mature  2 ductus differentiae  Vas differentia  45 cm long  Passes upwards along medial side of testes through inguinal canal, enters pelvic cavity  Ends behind urinary bladder  2 ejaculatory ducts  Urethra  2 seminal vesicles  Convoluted  Saclike  5 cm long  Attaches to ductus deferens on posterior surface near urinary bladder  Prostate gland  Chestnut shape  4 cm across, 3 thick ‘surrounds proximal part of the urethra  Inferior to urinary bladder  Enclosed in connective tissue – composed of branched tubular glands – open into urethra  2 bulbourethral glands  1 cm in Diameter  Inferior to prostate gland  Semen  Fluid in male urethra – leaves during ejaculation  Sperm cells + seminal vesicle secretions  pH 7.5  prostaglandins  nutrients EXTERNAL REPRODUCTIVE ORGANS o Penis  Conveys urine and semen to outside  Stiffens during erection for sexual intercourse Orgasm o Pleasurable feeling of physiological + psychological release o In male – happens along with emission + ejaculation 

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19.3 Hormonal control of male reproductive functions 

Hypothalamus, anterior pituitary gland, testes secretes hormones that control reproductive organs o Initiate and maintain sperm cell production

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o Oversee development/ maintenance od 2 nd sex characteristics HORMONES o Androgens – interstitial cells of testes produce it  Slos in adrenal cortex o Testosterone – most important androgen  Secreted by testes, transported in blood  Loosely attached to plasma protein  Begins during fetal development – continues for several weeks post birth o Puberty – reproductive organs become functional ACTIONS OF TESTOSTRONE o Increase of body hair – face, chest, axillary region, pubic region – may slow growth of hair on scalp o Enlargement of larynx, thickening of the vocal folds, lowering of pitch of voice o Thickening of skin o Increased muscular growth, broadening of shoulders, narrowing of waist o Thickened, strengthened bones 19.4 Organs of female reproductive system

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Produce/ maintain female sex cells o Transport cells to site of fertilization o Provide favorable environments for developing offspring o Deliver offspring Primary sex organs o 2 ovaries – produce sex cells + sex hormones Accessory organs o Internal/ external reproductive organs Ovaries o Solid ovoid structures o 3.5 cm long o 2 cm wide o 1 cm thick o Lie in shallow depressions in lateral wall of pelvic cavity Zygote o chromes of egg and sperm combine primary oocyte w/in mature antral follicle is large, spherical cell o surrounded by zona pellucida  with layer called corona radiata  follicular cells extend through the zona pellucida – supply nutrients to primary oocyte Ovulation o Releases egg cells from ovarian follicle o After Ovulation

1 or 2 layers of foliar cells surrounded it are normal propelled to opening of uterine tube  Mature atrial follicle is large  If oocyte not fertilized within hours – degenerates INTERNAL ACCESSORY ORGANS o Uterine tubes  Open near ovaries  10 cm long  .7 cm in diameter  Passes medially to uterus, penetrates the wall  Opens into uterine cavity o Uterus  Hollow, muscular  Shaped like a pear  Receives the embryo – sustains the development  Size changed during pregnancy  Normal – 7 long x 5 wide x 2.5 diameter  Medially in anterior part of pelvic cavity  Superior to vagina  Bend forward of urinary bladder o Vagina  Fibromuscular tube  9 cm long  Extend from uterus to outside of body  Conveys uterine excretions  Receives erect penis  Provides passage way for offspring to exit EXTERNAL REPRODUCTIVE ORGANS o Labia majora  Enclose/ protect other external reproductive organs  Folds of adipose tissue, thin layer of smooth muscle, covered in skin  Lie closely together  Cleft includes the urethral + vaginal openings separates labia longitudinally o Labia minora  Flat  Longitudinal folds between labia majora o Clitoris  Small projection  Anterior end of vulva between labia minora  2 cm long x .5 cm diameter  Corpora cavernosa o Vestibular glands 

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19.5 hormonal control of female reproductive system 

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Hypothalamus, anterior pituitary gland, ovaries secrete hormone o Control maturation of sex cells o Maintenance/ development of secondary sex characteristics  Changed with Menstruation cycle Sex Hormones o Reproductively immature until 10 yrs. old o Hypothalamus secretes GnRH  Then stimulated anterior pituitary releases – gonadotropins FSH LH  Controls maturing sex cells, and producing female sex hormones Ovaries, adrenal cortices, placenta secrete hormones in 2 groups o Estrogen o Progesterone After puberty o Development of breasts, ductile system of mammary glands o Increased deposition of adipose tissue in Subq layer in breasts, thighs, butt o Increased vascularization of skin Menstrual cycle o Regular, recurring changes in endometrium – culminates in bleeding o Menarche – females fist cycle  Occurs after organs start responding to hormones Menopause o When menstrual cycle stops o Female climacteric o Reduced concentrations of estrogens and lack of progesterone – changes secondary sex characteristics  Breasts, vagina, uterus, uterine tubes may shrink  Pubic/axillary hair may thin 19.6 mammary glands

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Accessory organs of female reproductive system Secrete milk following pregnancy In Subq tissue of anterior thorax – breasts Overlie pectoralis major muscles – extend form 2nd to 6th ribs o Sternum to axillae Nipple located near tip of each breast - @ 4 th intercostal space Areola – circular pigmented skin, surround nipple 19.7 birth control

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Birth control – voluntary regulation of # of offspring produced, time conceived o Contraception – avoids fertilization Mechanical barriers o Male condom – latex sheath

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o Female condom – resembles small plastic bag Combined hormone contraceptives o Deliver estrogen, progesterone to prevebt pregnancy  Small ring inserted into vagina once a month – stays in3/4 weeks  Plastic patch impregnated w/ hormones applied to skin  Pill Sterilization o Sterilize male/female o Male – cuts vas deferens ties ends  Vasectomy o Female – uterine tubes are cut and tied 19.8 STIs

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Describes prevalent disease associated with STDs

Disease Aids

Cause HIV

Chlamydia

Chlamydia trachomatis bacteria

Genital herpes Genital warts Gonorrhea

HSV2 HPV Neisseria gonorrhoeae bacteria Treponema pallidum bacteria

Syphilis

Symptoms Treatment Fever, weakness, Drugs to treat/ delay infections, cancer symptoms Antibiotics Painful urination + intercourse Mucus discharge Genital sores, fever Antibiotics Warts Chem/ surgery Women – none Antibiotics Men – painful urination Chancre on genitals/ Antibiotics mouth, rash, heart/liver/nerve damage...