Chapter 20 Flashcards
The testes stop making testosterone by the _________, and the ovaries don’t make embryonic sex hormone.
Third trimester
Sex hormone secretion does not occur again in either sex until the gonads are stimulated at _______.
Puberty
Once the sex hormone secretion occurs, the anterior pituitary begins releasing _________.
Gonadotropic hormones
Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) are produced in the ________ of both males and females with three effects.
Anterior pituitary glands
The stimulation of spermatogenesis, stimulation of gonadal hormone secretion, and maintenance of the structures of the gonads are the three effects of what?
FSH and LH that are produced in the anterior pituitary glands
The release of FSH and LH is controlled by the release of gonadotropin-releasing hormone (GnRH) from the ________.
Hypothalamus
The regulation of FSH and LH is regulated by a negative-feedback loop where rising levels of _________ and inhibiting the GnRH release, and inhibiting the pituitary response to GnRH.
Gonadal hormone
Aside from the usual gonadal hormones, the gonads also secrete _______.
Inhibin
The inhibin is secreted by _____ in the testes.
Sertoli cells
The inhibin is secreted by granulosa cells of ________ follicles.
Ovarian
The inhibin specifically inhibits release of ____.
FSH (no effect on LH)
Secretion of ______ is pulsatile so FSH and LH are also pulsatile (more apparent in females than males).
GnRH
Frequency of pulsations affects the _______ response.
Target gland’s
Secretion of FSH and LH is elevated at _____ and stays high for the first 6 months of postnatal life.
Birth
After secretion of FSH and LH is elevated at birth, it declines to almost nothing until ______.
Puberty
Puberty begins with a release of ______.
LH (pulsatile)
Puberty begins with a release of LH due to the declining sensitivity of the hypothalamus to negative feedback effects of ______.
Gonadal hormones
Puberty begins with a release of LH, which results in increases in ________ or estradiol-17Beta secretion.
testosterone
Puberty begins with a release of LH, which produce _____ sex characteristics.
Secondary
The secondary sex characteristics in ______ are growth spurts, breast development, and menarche (first menstrual flow).
Girls
The secondary sex characteristics in ____ are later growth spurts, and body, muscle, penis, testis growth.
Boys
The secondary sex characteristics in both sexes is body hair is stimulated by ______ from adrenal gland at puberty.
Androgens
Age of the onset of puberty depends on ______ and amount of body fat.
Activity levels
_____ is secreted by adipose cells is required for the onset of puberty.
Leptin
In the onset of puberty, ______ may inhibit GnRH secretion.
Exercise
More ______, ______ girls begin puberty later.
Active, Slimmer
______ from the pineal gland may play a role in onset of puberty, but this is not proven in humans.
Melatonin
______ is a human sexual response that is characterized by increased muscle tone, vasocongestion of sexual organs; also called arousal.
Excitation
_____ is a human sexual response that continues vasocongestion.
Plateau
____ is a human sexual response that causes contraction of the uterus/vagina and male ejaculatory organs.
Orgasm
____ is a human sexual response where the body returns to pre-excitation condition.
Resolution
Men experience a ________ where that are not able to ejaculate.
refractory period
The two compartments of the testes are the _____ and _______.
Seminiferous Tubules and Interstitial Tissue
The ______ in the testes are where spermatogenesis occurs.
Seminiferous Tubules
In the seminiferous tubules, the FSH receptors are found on the _______.
Sertoli Cells
In the seminiferous tubules, the FSH influences _______.
Spermatogenesis
The ________ is the testes are where Leydig cells make testosterone; also filled with blood and lymphatic capillaries.
Interstitial Tissue
In the interstitial tissue, the LH receptors are found on the ________.
Leydig Cells
In the interstitial tissue, ______ is secreted in response to LH.
Testosterone
______ secretion is controlled by rising testosterone secretion through negative feedback.
LH
______ secretion is controlled by testosterone and inhibin secretion.
FSH
_______ is released from the Sertoli cells of the seminiferous tubules.
Inhibin
_______ is converted to its derivatives in brain cells.
Testosterone
_______ in converted by 5a-reductase to DHT, other androgens, or to estradiol by aromatase enzyme.
Testosterone
_______ is used to inhibit LH secretion.
Estradiol
Male and female brains are different due to the effects of ______ and ______.
Testosterone and estradiol
Negative feedback effects of ____ and ___ maintain a relatively constant secretion of gonadotropins in males.
Testosterone and inhibin
Androgen secretion declines slowly in males to a hypogonadal state by age ____.
70
Other factors that affect testosterone secretion are ______, ______, ______.
Physical inactivity, obesity, drugs
______ is secreted by Sertoli cells, Leydig cells, and developing sperm.
Estradiol
Receptors for ______ are on Sertoli and Leydig cells, cells lining the ducts, and accessory glands.
Estradiol
The role in ______ is to regulate the enviornment of developing sperm, fluid reabsorption, and sealing epiphyseal plates.
Spermatogenesis
Growth and development of wolffian ducts into epididymis, ductus deferens, seminal vesicles, ejaculatory ducts, urogenital sinus into prostate and male external genitalia describes the actions of what androgen in the male?
Sex Determination
At puberty the completion of meiotic division and early maturation of spermatids, and after puberty the maintenance of spermatogenesis describes the action for what androgen in the male?
Spermatogenesis
Growth and maintenance of accessory sex organs, growth of the penis, facial, and axillary hair, and body growth describes the action of what androgen in the male?
Secondary Sex Characteristic
Protein synthesis and muscle growth, growth of bones and other organs, and erythropoiesis is the action for what androgen in the male?
Anabolic Effects
In _______, germ cells from the yolk sac migrate to the testes early in embryonic development.
Spermatogenesis
Diploid spermatogonia first go through _____ to increase the number of cells.
Mitosis
In spermatogenesis, one of the daughter cells continues through meiosis and the other daughter cell remains a _______.
Spermatogonial cell
In spermatogenesis, after meiosis 1 it goes to 2 secondary _____.
Spermatocytes
In spermatogenesis, after meiosis 2 there are 4 _______.
Spermatids
In spermatogenesis, the process occurs as the cells move toward the _____ of the seminiferous tubules.
Lumen
_____ is the maturation of spermatids into functioning spermatoza.
Spermiogenesis
Protamines replace ____ associated with DNA.
Histones
Sperm development requires ____ cells.
Sertoli