It is inherited in an autosomal recessive manner and is caused by a mutation in the HBB gene. The mutation that causes hemoglobin E disease primarily occurs in Southeast Asian populations, and rarely in Chinese populations. Most people with HbE disease do not need any treatment.
CHAPTER 27 Homework Review ï· The ability of sperm cells to move along the ductus deferens is due to ________. peristaltic contractions ï· Prostate cancer is _______.sometimes a slow-growing cancer that may never represent a threat to the patient ï· Erection of the penis results from ________.a parasympathetic reflex ï· Why doesn't semen enter the ...
The smooth muscle tissue contracts in waves of peristalsis to slowly push the sperm along the length of the epididymis toward the ductus deferens. When sperm first enters the epididymis from the testis, it is very immature and diluted by a relatively large volume of liquid. The smooth muscle of the epididymis pushes the sperm along tubule with slow waves of peristalsis, so that the sperm traverse its entire 20-foot length in about two weeks.