to make sure the testis operates at a temperature
below body temperature. The accessory glands
consist mainly of the prostate gland and the
seminal vesicle, and they are the two glands
that I’m going to describe now. Let’s go
back to this diagram just to remind you
of where the seminal vesicle lies and where
the prostate lies. The seminal vesicle, you
can see in this diagram, lies just at the
posterior aspect of the bladder, at least
from the angle you’re looking at. And the
prostate gland is below the bladder. And just
refresh your memories about the ejaculatory
duct coming from the seminal vesicle into
the prostate to join the prostatic urethra.
And there, the secretion products from the
seminal vesicle and the prostate will pass
into the urethra during ejaculation and flash
the spermatozoa out that have been delivered
to the urethra by contraction of the vas deferens
and also the epididymis. Let’s now have a
look at this seminal vesicle in a bit
more detail. Here, you can see a number of different
features that are characteristic of the seminal
vesicle. It has got a fairly thick muscular wall.
And it has got a very, very folded mucosa.
You’ll see that more clearly on the right-hand
side section taken at high magnification.
This seminal vesicle forms a very long convoluted
sac, and it all connects to the ejaculatory
duct. And this sac, as I mentioned, is convoluted.
It’s very, very folded with lots of muscle
making up the wall. The epithelium secretes
fluid, and that fluid is rich in fructose
which is the major energy supply for the sperm.
Often, you see the seminal vesicle containing
lots of colloid type material in the lumen.
This reflects the fluid containing all
these fructose. The prostate gland is the largest
accessory gland. It secretes a watery slightly