Male Internal Organs: Critical Gestation Event
The development of internal sex organs in males during the 3rd month of gestation is a hormonally regulated process initiated by the fetal testes.
AMH Role in Male Internal Organ Development
- Antimullerian hormone (AMH), produced by the Sertoli cells of the developing testes, is crucial.
- AMH induces the regression (degeneration) of the Mullerian ducts.
- Mullerian ducts are precursors to female internal reproductive structures like the uterus and fallopian tubes.
- The elimination of Mullerian ducts ensures that male internal organs, derived from Wolffian ducts (epididymis, vas deferens, seminal vesicles), can develop properly.
- Therefore, the presence of AMH is a critical event for establishing the male internal reproductive system by preventing the development of female structures.
Other Factors in Male Sex Organ Development
- The 'sry gene' activation is essential for initiating testis development itself, which precedes AMH production.
- Dihydrotestosterone (DHT) is vital for the development of external male genitalia and accessory glands, impacting different structures than those in question.
- While testis development is foundational, AMH's specific action on Mullerian duct regression is the key event for differentiating the internal sex organs in males during this gestational period.
Important Questions from System Physiology Animal
Which one of the following synaptic vesicles (as observed under transmission electron microscope) contains catecholamines?
Blood hemostasis is the interplay of several intrinsic and extrinsic factors. Deficiency of some of the blood clotting factors and their clinical manifestations are listed below.
Factors
Manifestations
A.
V
i.
Hageman trait
B.
VII
ii.
Hypoconvertemia
C.
IX
iii.
Hemophilia B
D.
XII
iv.
Parahemophilia
Which one of the following options represents all correct matches?
Columns X and Y list the terms associated with gametogenesis and fertilisation.
Column X
Column Y
A
Primordial germ cells
i
Luteinizing hormone
B
Dictyate resting stage
ii
Posterior epiblast
C
Sodium channels
iii.
Male pronuclei
D
Protamines
iv
Block polyspermy
Which one of the following options represents all correct matches?
Nephrons are structural and functional units of the kidneys. Certain statements are made below about structure and function of a nephron.
A. P cells of the collecting duct are involved in Na+ reabsorption and vasopressin-stimulated water reabsorption.
B. P cells of the collecting duct are concerned with acid secretion and HCO3- transport.
C. I cells of the collecting duct are concerned with acid secretion and HCO3- transport.
D. The total length of the nephrons including collecting ducts ranges from 45 to 65 mm.
Which one of the following options has all correct statements?
The non-ciliated cuboidal epithelial cells in bronchioles that secrete important defense markers are called
