Exam II: Sexual Development and Repro. Hormones Flashcards
Which type of sexual differentiation is determined at fertilization
Genetic sex
What are the testis determining genes?
SRY and SOX9
Which hormones are involved in phenotypic sex?
AMH, T, DihydroT
What does SRY stand for?
Sex Determining region of the Y chromosome
Where is SRY synthesized
In sex cord of male
What do the Sex cords in males differentiate into?
Seminiferous tubules and rete testis
Which cells in the male produce AMH?
Pre-sertoli cells
What happens to the sex cords in the absence of SRY?
Develop into follicles
How does free martinism happen?
male and female calf
Fusion of placental circulation
AMH transferred from male to female
Disagreement b/t chromosomal and gonadal sex
Sex reversal
What are the two functional areas for secretion of GnRH in Females?
- Tonic
2. Surge
What is the effect of T on the hypothalamus?
T crosses the BBB and is converted to estradiol, which defeminizes the hypothalamus, eliminating the surge center
T/F Estradiol does not cross the BBB?
T
Why does Estradiol produced by the ovaries not cross the BBB?
Bound to alpha-fetoprotein
The key to development of a testis rather than an ovary in mammals is:
a. TDF
b. T
c. Estradiol
d. Epithelial growth factor
e. Neuropeptide Y
a.
Signaling molecules produced i the body that regulate activity of certain cells and organs
Hormones
What are the 3 main classes of hormones?
- Steroids
- Peptides
- Eicosanoids
What are the 2 endocrine hormones discussed in class?
- Estradiol
2. FSH
What is the Neuroendocrine hormone discussed in class?
1 GnRH
Paracrine or Autocrine:
T from Leydig cells influences sertoli cells in the testis.
Paracrine
Paracrine or Autocrine:
E from Sertoli cells hastens pubertal development of these cells
Autocrine
T/F. Endocrine control is faster, but longer lasting than neural control
F. Slower and longer lasting
T/F Hormones have relatively short half lives
T
What are the 4 characteristics of hormones discussed in class?
- Act in low quantities
- Short half lives
- bind to specific receptors
- Regulate intracellular biochemical reactions
What are the 4 determinants of strength of a hormone?
- Pattern and duration of secretion
- Half life
- Receptor density
- Affinity receptor hormone
The rate at which a hormone is cleared from the circulation
Half life
Bind to the specific receptor and have the same biological response that the native hormone
Agonist
Produces maximal response greater than endogenous hormone
Super agonist
Bind to the receptor but it has weak or no biological effect
Antagonist
Where is GnRH produced?
Hypothalamus
Where is FSH, Oxytocin and LH produced?
Pituitary gland
Where is estradiole, T, inhibin, relaxin and progesterone produced?
Ovary
Where is T, inhibin, and Estradiol produced
Testis
Where is PGF2a produced?
Uterus
What are the 4 ways we can classify hormones based on biochemical structure?
- peptide
- glycoproteins
- Steroids
- Prostaglandins
Which cells in the ovaries produce E (Estradiol)?
Follicular cells
Generic term for molecules with action like estradiol
Estrogens
How are endogenous estrogens synthesized?
Synthesized from androgens by action of aromatase
Where is progesterone produced?
CL of Ovary
What are the 2 cell types of the ovary?
Granulosa and theca cells
Which cell type of the ovary, granulosa or theca, make Progesterone?
Both
Where is Progesterone metabolized?
Liver
What are the functions of P?
- Development and function of uterus
- Closes off cervix
- maintenance of Pregnancy
- development of mammary glands
Class of hormones that bind to P receptors?
Progestagens
Bigest source of T in the male
Leydig cells of the testes
Where is T metabolized
Mostly in liver, some in prostate
Functions of T
- Masculinization
- Maturation of male repro tract
- Spermatogenesis
- Muscle mass, bone density
Class of compounds binding to androgen receptors, T-like hormones
Androgens
T/F Estradiol can have both positive and negative feedback effects at the level of the hypothalamus
T
