2S [LEC]: Reproductive Organs, Thymus Gland, Pineal Gland Flashcards
Main source of sex hormones
Gonads
A pair of small, almond-shaped organs located in the female reproductive system
Ovaries
A pair of oval-shaped organs located within the scrotum and is responsible for producing sperm cells and synthesizing testosterone
Testicles
Cells that synthesize testosterone
Leydig cells
Hormones that primarily controls testosterone production
FSH, LH
Best time for sample collection in testosterone determination
8-10 AM
Principal androgen hormone in the blood
Testosterone
Hormone that develops ovarian follicles
FSH
Hormone that promotes the production of estrogen and testosterone
LH
Hormone that would act on seminiferous tubules to produce testosterone
FSH
Hormone that would act on Leydig cells to produce testosterone
LH
A C18 steroid hormone with a phenol A ring
Estrogen
Arises through structural alteration of the testosterone molecule
Estrogen
T/F: Estrogen is not produced by the ovaries after menopause
True
Hormone that primarily promotes breast development, maturation of the external genitalia, deposition of body fat and termination of linear growth
Estrogen
Active form of estrogen
Estradiol
To measure the ovarian function, which estrogen form is used?
Estradiol
Major estrogen secreted during pregnancy
Estriol
To measure the fetoplacental viability, which estrogen form is used?
Estriol
An estrogen form that is decreased in trisomy 21
Estriol
Precursor of estrone and estriol
Estradiol
Cells that mainly produce progesterone
Granulose (lutein) cells
Dominant hormone responsible for the luteal phase cycle among females
Progesterone
Used primarily for the evaluation of fertility in female
Progesterone
Which analytes are increased in down syndrome?
HCG, Inhibin A
Which analytes are decreased in down syndrome?
AFP, UE3
Genetically female but whose phenotypic characteristics are, to varying degrees, male
Female pseudohermaphroditism
Female pseudohermaphroditism occurs when there is an exposure to ___ before the 12th week of gestation
Androgen (testosterone increase)
Development of secondary sexual characteristics in <8 yo female and <9 yo male
Precocious puberty
The most common form of hypogonadotropic hypogonadism due to deficiency of GNRH
Kallman Syndrome
Sex affected by Kallman Syndrome
Both males and females
Androgen insensitivity syndrome
Testicular Feminization Syndrome
Level of testosterone in Testicular Feminization Syndrome
Low (primary hypogonadism)
A genetic condition in males where they are born with an extra X chromosome, leading to infertility, reduced testosterone levels, and potential development and physical differences
Klinefelter syndrome
Level of testosterone in Klinefelter Syndrome
Low (primary hypogonadism)
A surgical procedure to remove one or both testicles, which causes primary hypogonadism
Orchidectomy
Condition that occurs in one-third of post-pubertal males with mumps infection
Mumps Orchitis
One of the leading causes of male infertility
Mumps Orchitis
Level of testosterone in Mumps Orchitis
Low (primary hypogonadism)
A condition in which one or both testes fail to descend into the scrotum during fetal development
Cryptorchidism
Level of testosterone in Cryptorchidism
Low (primary hypogonadism)
Characterized by a lack of germ cells
Sertoli-Cell Only Syndrome/ Del Castillo Syndrome/ Germ Cell Aplasia
The hallmark of disorders of hypogonadotrophic hypogonadism
Hypogonadotropic hypogonadism
Lies in the upper part of the thoracic cvity
Thymus gland
Helps in the development of T cells
Thymosin
Small pinecone shaped gland located in the middle of the brain
Pineal gland
Decreases the secretion of LH and FSH by decreasing the release of hypothalamic releasing hormone
Melatonin
Regulates sleep and wake cycle
Melatonin
Cells in the pineal gland that synthesizes melatonin
Pinealocytes
What inhibits the secretion of melatonin?
Light stimuli
T/F: Melatonin has only secreted during the dark period of the day
True
