Reproduction Flashcards
How does spermatogenesis occur?
In Sertoli cells, requires oestrogen and FSH
What is testosterone?
Made from cholesterol. Anabolic steroid produced from Leydig cells.
Placental permeability - oxygen diffuses from what paO2 maternal to foetal?
50mmhg maternal to foetal 30mmhg
What is the Bohr effect in placental diffusion?
The Bohr effect describes how hemoglobin’s affinity for oxygen decreases in the presence of elevated carbon dioxide (CO₂) levels and lower pH (acidic conditions). This allows oxygen to be released more readily where it is needed, such as in tissues with high metabolic activity.
Maternal side:
CO₂ produced by the fetus diffuses across the placenta into maternal blood.
This increases the CO₂ level and lowers the pH in maternal blood near the placenta.
The Bohr effect causes maternal hemoglobin to release oxygen more readily in this environment.
Fetal side:
Fetal blood, which has taken up oxygen, has less CO₂ and a higher pH.
Fetal hemoglobin (HbF) is structurally different and has a higher affinity for oxygen than maternal hemoglobin (HbA), so it effectively captures the released oxygen.
The Bohr effect ensures that oxygen delivery to the fetus is enhanced and that CO₂ diffusion from the fetus to the mother is efficient.
What regulates prolactin?
Prolactin inhibitory factor from the hypothalamus which supresses prolactin secretion.
What is meconium?
Amniotic fluid, mucus, bile, cells shed from intestinal lining
What are the circulatory changes at birth?
Increased systemic vascular resistance. Decreased pulmonary vascular resistance. Closure of foetal shunts (3).
When does PT/aPTT normalise in the foetus?
PT at 7days 1.7x adult
aPTT at 10d to normal adult levels
What is surfactant?
Lipoprotein synthetised by type 2 pneumocytes that eliminates surface tension
What is Laplace’s law?
P = 2T/ r
What causes cartilage formation suppression in neonates?
Fluroquinolones
