Rectum/Anus/Perineum Flashcards
Which is true?
A The rectum is bound dorsally by the levator ani muscles.
B The rectum does not contain a serosal layer.
C In cats, the intrapelvic rectum is supplied by the middle and caudal rectal arteries.
D In dogs, the intrapelvic rectum is supplied by the middle and caudal rectal arteries.
A (right and left ventral sacrocaudal muscles).
B (retroperitoneal portion only)
C true
D (cranial rectal)
Which is true?
A The internal and external anal sphincters are striated muscle.
B The mucosa of the anal canal is divided from cranial to caudal as cutaneous, columnar, and intermediate zones.
C The columnar zone contains the anal sinuses.
D The duct from the anal sac opens into the internal portion of the internal cutaneous zone.
A (internal is smooth)
B (columnar, intermediate, and cutaneous)
C (intermediate zone - anal sinuses)
D TRUE
Which of the following statements is true?
A The anal sacs usually open within the intermediate zone
B The pernieal body is where the fascia unites on midline ventral to the anus
C Circumanal glands are large, coilled apocrine, sudoriparous tubules
D As an involuntary muscle, the external anal sphincter permits maximum distension
A (inner cutaneous zone) B TRUE C (paranal sinus glands = foul-smelling paste circuma anal = sebaceous/nonsebaceous) D (voluntary)
Which of the following statements is true?
A The rectococcygeal muscles blend to form a muscle that inserts on the 5th to 6th caudal vertebrae
B The pelvic and hypogastric nerves supply voluntary and motor innervation to the anal sphincter
C Cells of Baine are electrical pacemaker cells enable slow waves to be rapidly conducted between longitudinal and circular muscle
D Enema should always be given the day of surgery
A true
B pelvic = parasympathetic
hypogastric = sympathetic
pudendal –> caudal rectal br = voluntary motor
–>perineal Br = sensory
C (Cajal)
D could give low residue, high calorie diet 2-7 days prior to sx
True or false: Fecal material contains 75% anaerobes, and second generation cephalosporins are more effective against some pathogens compared to first gen cephalosporins.
False: 90% anaerobes
What makes up the pelvic diaphragm?
pelvic fascia, paired coccygeus and levator ani m.
Which of the following statements is false in regards to the secretion function of the colon?
A Mucus is a key molecule that protects epithelial cells from abrasion and bacterial invasion.
B Na+ 2Cl K ion channel has its enhanced activity triggered by increased intracellular Cl− concentration as a result of absorption of Cl− ions at the apical border.
C Intracellular potassium levels are maintained by the presence of two potassium channels that are triggered by increases in intracellular Ca2+ or cyclic adenosine monophosphate
D Absorption and secretion by colonocytes are regulated by a complex interaction of endocrine autocrine, paracrine, and neuronal stimuli.
B Na+ 2Cl K ion channel has its enhanced activity triggered by LOWERED intracellular Cl− concentration as a result of SECRETION of Cl− ions at the apical border.
cystic fibrosis transmembrane regulator Cl- efflux enhanced by increased intracellular Cl-
- Distal colonic transit is slow to ensure that fecal contents are mixed, this is achieved by a combination of ___ +____movement and, in the proximal colon of cats, by _____.
segmentation and propulsive
retrograde peristalsis
Colonic wall intrinsic plexuses, are located between the longitudinal and circular muscle layers ____ or in the colonic submucosa ____. Parasympathetic innervation via preganglionic ____+_____ fibers stimulates colonic motility, sympathetic stimulation via the _____+____ inhibits it.
(myenteric or Auerbach)
(submucous or Meissner plexus)
vagal and pelvic
mesenteric plexus and hypogastric plexus
How are shorty chain fat acids absorbed? Where?
Butyrate, acetate and propionate in colon, absorbed by paracellular paths and non-ionic diffusion
What proteins help play a role in water absorption on the basolateral membrane of colonocytes?
Aquaporin -3 and -4
What is the Major blood supply of the cecum?
Common colic a—> ileocolic artery
What are the circumanal glands and their roll?
Superficial sebaceous portion and deep nonsebaceous part
Regress in adult female dogs
What are anal glands and what do they produce?
Tubuloalveolar glands that produce fatty secretions
What glands are found in the wall of the anal sac and produce foul smelling paste?
Paranal sinus glands = large coiled apocrine sudoparous tubules
