Chapter 112: Penis and Prepuce Flashcards
Which part of the penis contains the urethra?
Corpus spongiosum
Which part of the penis is most responsible for expansion during erection?
Bulbus glandis (can expand most dorsally / more than pars longa)
What is another name for the os penis?
Baculum (begins just caudal to bulbus and extends almost to tip of glans).
The dorsal 2/3 is indented ventrally for the groove of the penile urethra and corpus spongiosum
What are the (4) paired extrinsic muscles of the penis?
- Retractor penis
- Ischiocavernosus
- Bulbospongiosus
- Ischiourethralis
What is the physiologic cause of erection?
- Parasympathetic stimulation causes profound increase of bloodflow through internal pudendal artery
- Engorgement of cavernous bodies due to expansion of arteries and contraction of veins
- Dorsal penile vein is compressed against ischial arch due to contraction of ischiocavernosus and bulbospongiosus muscles (blood can’t get out)
What occurs to the prepuce at puberty?
- Separation of the prepuce from the penis and break down of the ventral frenulum under androgen influence
What is the only species that does not require erection for penile function during copulation?
Dogs, due to the os penis
What are the spines on the cat penis?
Small, cornified papillae that appear at between 12 weeks and 7 months of age and regress within 6 mo of castration.
Is the inner lining of the prepuce mucosa?
NO
It is a reflection of stratified squamous epithelium.
What are the three branches of the artery of the penis (from internal pudendal a.)?
Artery of the bulb
Deep artery of penis
Dorsal artery of penis
What are the three divisions of the penis?
Root - attached to ischial tuberosities
Body - from crura to proximal end of os penis
Distal (glans)
The enlarged venous spaces in the penis are called the?
Corpora
(corpus cavernosum/spongiosum)
