NRSG 112 ch 2 notes PDF

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Reproductive system anatomy and physiology notes...

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CHAPTER 2 HUMAN REPRODUCTIVE ANATOMY AND PHYSIOLOGY      

Boys grow taller, more muscular, and develop pubic and facial hair and a deepened voice. Girls experience menarche, broadened hips, breasts, and pubic and axillary hair. Rapid change in boys and girls during which the reproductive system matures and becomes capable of reproduction Begins when the secondary sex characteristics (e.g. pubic hair) appear Ends when mature sperm are formed or when regular menstrual cycles occur **transition from childhood to adulthood, some cultures celebrate

The hormone levels in the male are constant, not cyclic as in females. Male Hormonal changes normally begin between 10 and 16 years  Outward changes become apparent when the size of penis and testes increases and there is a general growth spurt  Testosterone (primary male sex hormone) causes the boy to grow taller, more muscular and develop secondary sex characteristics: 1. Pubic hair 2. Facial hair 3. Deeper voice-often squeaks or cracks before reaching its final pitch  Testosterone levels are constant, not cyclical as female hormones  Nocturnal emissions “wet dreams” may occur without sexual stimulation (usually do not contain sperm) What is the first outward change of puberty in males? 1) Development of pubic hair 2) Nocturnal emissions 3) Voice deepens 4) Penis and testes increase in size Male (internal)  Testes, Vas Deferens, prostate, seminal vesicles, ejaculatory ducts, urethra, and accessory glands  Testes-Manufacture male germ cells (spermatozoa or sperm) and secrete male hormones (androgens)  Testosterone (most abundant male sex hormone begins with the anterior pituitary gland, The hypothalamus directs the anterior pituitary gland to secret follicle-stimulating hormone (FSH) and luteinizing hormone (LH). These hormones initiate the production of testosterone in the Leydig cells of the testes. 

Other related effects of Testosterone:

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Increases muscle mass and strength Promotes growth of long bones Increases basal metabolic rate Enhances production of red blood cells Produces enlargement of vocal cords Affects the distribution of body hair

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epididymis stores and carries the sperm to the penis, sperm remains for 2 to 10 days, during which time they mature and then move on to the vas deferens The ejaculatory ducts then enter the back of the prostate gland and connect to the upper part of the urethra, which is in the penis Accessory glands-seminal vesicles, prostate gland, bulbourethral gland (Cowper’s gland. These glands produce secretions (seminal plasma) They have 3 functions: 1.Nourish the sperm 2. Protect the sperm from the acidic environment of the woman’s vagina 3. Enhance the motility (movement) of the sperm ****combined seminal plasma and sperm are called (Semen)

FEMALE  1st outward change is development of breasts  1st menstrual period (menarche) occurs 2 to 21/2 years later (age 11 to 15 years)  Female reproductive organs mature to prepare for sexual activity and childbearing  Female growth spurt: o Hips broaden-pelvis assumes the wide basin shape needed for birth o Pubic and axillary hair External Genitalia (collectively called vulva) include: • Mons pubis • Labia majora • Labia minora • Fourchette • Clitoris • Vaginal vestibule • Perineum  

The external genitalia have an extensive venous supply. In the event of sexual trauma, bruising and swelling are common.

Internal female reproductive organs

Internal- vagina, uterus, fallopian tubes, and ovaries Vagina- tubular structure made of muscle and membranous tissue that connects the external genitalia to the uterus, self-cleansing and has a normal pH of 4 to 5 (acidic)  Has 3 functions: 1. Provides a passageway for sperm to enter the uterus 2. Allows drainage of menstrual fluids and other secretions 3. Provides a passageway for the infant’s birth

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The uterus is known as the womb. Uterus- (womb) hollow muscular organ in which a fertilized ovum is implanted (embryo) forms and fetus develops IMP: because the autonomic nervous system innervates the reproductive system, its functions are not under voluntary (conscious) control. Therefore: EVEN a paraplegic woman can have adequate contractions for labor…….. Anatomy: uterus is separated into 3 parts 1. Fundus 2. Corpus 3. Cervix Mucosal lining has four functions (uterus) ◦ Lubricates vagina ◦ Acts as a bacteriostatic agent ◦ Provides alkaline environment to shelter deposited sperm ◦ Produces a mucus plug in cervical canal during pregnancy

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The fallopian tubes are the most common site for ectopic pregnancies.

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Fallopian tubes- uterine tubes or oviducts, has 4 functions: 1. Passageway in which sperm meet the ovum 2. The site of fertilization 3. A safe, nourishing environment for the ovum or (Zygote-fertilized ovum) 4. The means of transporting the ovum or zygote to the corpus of the uterus **have cilia (hairlike projections) that beat rhythmically to propel the ovum toward the uterus

Ovaries- located on each side of the lower abdominal cavity

2 functions: 1. Production of hormones, chiefly estrogen and progesterone 2. Stimulation of an ovum’s maturation during each menstrual cycle   

At birth, every female has all the ova that she will have throughout her reproductive years (around 2 million) By adulthood, number of ova is in the thousands By climacteric (menopause), the ova no longer mature in response to hormonal stimulation

Pelvis- (Bony pelvis) occupies the lower portion of the trunk of the body 4 bones attached to the lower spine: 1. Two innominate bones 2. Sacrum 3. Coccyx Has 3 functions: 1. Supports and distributes body weight 2. Supports and protects pelvic organs 3. Forms the birth passage way Types of Pelvis: 1. Gynecoid (MOST) favorable for vaginal birth 2. Android (typical of the male anatomy) 3. Anthropod 4. Platypelloid (unfavorable for vaginal birth)

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Separated by an imaginary line, the linea terminalis False pelvis • Supports the enlarging uterus • Guides fetus into true pelvis True pelvis • Dictates the bony limits of the birth canal

Breasts- mammary glands are accessory organs of reproduction, produce milk after birth to provide nourishment and maternal antibodies for the infant

Breast size does not play a factor in the ability of the glands to produce milk.

Montgomery’s glands ◦ Small sebaceous glands ◦ Secrete a substance to lubricate and protect breasts during lactation •

A. B. C. D.

1. During a prenatal clinic visit, a woman states that she probably will not plan to breastfeed her infant because she has very small breasts and believes she cannot provide adequate milk for a full-term infant. The best response of the nurse would be: “Ask the physician if he or she will prescribe hormones to build up the breasts.” “I can provide you with exercises that will build up your breast tissue.” “The fluid intake of the mother will determine the milk output. “The size of the breast has no relationship to the ability to produce adequate milk.”

Reproductive cycle and menstruation consist of regular changes in secretions of the anterior pituitary gland, ovary, and endometrial lining of the uterus  The anterior pituitary gland, in response to the hypothalamus, secretes folliclestimulating hormone (FSH) and Luteinizing hormone (LH).  Ovulation- occurs when a mature ovum is released from the follicle about 14 days before the onset of the next menstrual period  Menstruation- (menarche) occurs at about age 11 to 15 years  Average cycle occurs every 28 days plus or minus 5 to 10 days, flow lasts 2 to 5 days, with a blood loss of 30 to 40 ml and an additional loss of 30 to 50 ml of serous fluid  Climacteric- years during which the woman’s ability to reproduce gradual declines  Menopause- refers to the final menstrual period Puberty and the onset of menstruation begin at younger ages today than in previous generations. The physiological reactions in the phases are: Excitement – elevated heart rate and blood pressure Plateau – flushed skin, erection (male) Orgasmic – involuntary muscle activity in the rectum, vagina, and uterus (female) Resolution – return to baseline vital signs Sperm can reach fallopian tubes within 5 minutes ◦ Can remain viable in female for up to 4 to 5 days Posterior pituitary gland secretes oxytocin  Stimulates contraction of uterus and dilation of cervical canal...