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PUBERTY. The period between childhood and adulthood Begins with the influences of some hormones Pubertal growth and physical development are a result of activation of the hypothalamic-pituitary gonadal axis in late childhood. GABA, neurotransmitters. FEMALE: FSH
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The period between childhood and adulthood Begins with the influences of some hormones Pubertal growth and physical development are a result of activation of the hypothalamic-pituitary gonadal axis in late childhood
FEMALE: • FSH • stimulates ovarian maturation • granulosa cell function • estradiol secretion • LH • important in ovulation • involved in corpus luteum formation and progesterone secretion
MALE: • FSH • stimulates the production of spermatocytes in the presence of testosteron • LH • stimulates the interstıtıel cells of the testes(produce testosteron) • Adrenocortical androgens play a role in pubertal maturation(DHEA-axillary odor,adrenarche)
The properties of puberty • Development of sexual maturity • Increase rate in growth and development • Changes in ratios and structures of body components The adolescence stages • Early • Middle • Late These are defined by the development of primary and secondary sex characteristics (pubic hair,breasts,genitalia)
EARLY • First stage of puberty-SMR 2 • 10.5-14 yr in boys-lasts 0.5-2 yr • 10-13 yr in girls-lasts 0.2-1.2 yr • Nocturnal pulses of gonadotropine MIDDLE • SMR 3-4 • 12.5-15 yr in boys-lasts 0.5-2 yr • 12-14 yr in girls-lasts 0.9-3 yr • LH pulses become evident during the day time LATE • SMR 5:14-16 in boys, • 14-17 in girls
EARLY ADOLESCENCE • PHYSICAL DEVELOPMENT • Initiated by pulsatile secretion of pituitary gonadotropins and growth hormone FEMALE • Inrease in body fat(subscapular skinfold thickness measurement of adiposity) • Breast development : stimulation by ovarian estrogens(secreted in response to FSH) 8-13 yr • FSH-stimulates growth of the ovaries late SMR 1 • Estrogen-thickens vaginal mucosa increases pigmentation, vascularization of labia majora,slight enlargement of the clitoris,enlargement of uterus • Menses begin 2-2.5 yr later the breast buds
EARLY ADOLESCENCE • MALES • Testicular enlargement • LH-Testosterone = the seminoferous tubules, epididymis,seminal vesicles and prostate enlarge • Some degree of breast enlargement(40-65%) Relative excess of estrogenic stimulation: spontaneous resolution within 3 years
GROWTH ACCELERATİON • begins in EA for both sexes- • boys peak 2-3 yr later than girls • enlargement of hands and feet-arms and legs-trunk and chest • enlargement of the larynx,pharynx-change in vocal quality • dental changes-jaw growth,eruption of permanent teeth • development of acne-adrenal androgens
EARLY ADOLESCENCE SEXUALITY • awareness of socially defined roles • interest in sex • ejaculation • masturbation SELF CONCEPT • self consciousness increases • dieting behaivours-anorexia RELATIONSHIP • trend toward separation from family • selecting adults outside of the family as role models • often socialize in same sex peer groups • relationship to society centers on school
MIDDLE ADOLESCENCE • BIOLOGIC DEVELOPMENT: • Growth accelerates above the prepubertal rate of 6-7cm/yr • The growth peaks at 11.5yr at a top velocity of 8.3cm/yr-slows to a stop at 16yr in GIRLS • The growth peaks at 13.5yr at 9.5cm/yr-slows to a stop at 18yr in BOYS • Weight gain parallel linear growth • Muscle mass increases • Bone maturation correlates with SMR-epiphyseal closure is under androgenic control
MIDDLE ADOLESCENCE • Widening the shoulders in boys and of the hips in girls is hormonally determined • Doubling the heart size and lung vital capasity • Blood pressure,blood volume,hematocrit rise • Acne and body odor-androgenic stimulation of sebaceous and apocrine glands • Menarche in 30% of girls by SMR3 90% of girls by SMR4(12.6-12.9) • Spermarche occurs and the penis lengthens and widens
MIDDLE ADOLESCENCE SEXUALITY: • dating becomes a normative activity • homosexual experimentation • dating relationship is often superficial SELF CONCEPT: • The peer group exerts less influence over dress,activities and behavior • Girls may tend to characterize themselves according to interpersonal relationships • Boys may focus on abilities • Middle adolescsents often begin thinking seriously about what they want to do as adults • Question and analyze extensively
LATE ADOLESCENCE BIOLOGIC DEVELOPMENT: • The final stages of breast,penile and pubic hair development occur • By age 17-18yr in 95%of males and females , minor changes in hair distrubition often continue for several years • In males including the growth of facial and chest hair and the onset of male pattern baldness in a few • Slowing physical changes permit the emergence of a more stable body image • Relationships involve love,career decision