Flashcards in GI System Deck (145)
What is prehension?
Movement of food into the oral cavity using tongue, lips and teeth
What is mechanical breakdown?
Mastication to reduce the size of food
What is muccin?
Mixture of mucous and water
What is salivation for?
Mucous for lubrication, some contain enzymes for digestion
Where is saliva produced?
parotid/ serous gland
What is the composition of saliva?
Mucin, amylase (omnivores), bicarbonate, phosphate (ruminants), lysosome, antibodies, protein binding tannins, urea (ruminants)
What effects the composition of salivary in non-ruminants?
Secretion comp effected by blood flow- primary secretion isotonic with blood, at low flow secretion hypotonic, at high rates remains isotonic
How is a ruminants composition of saliva affected?
Secretion is always isotonic to blood, at low flow PO4 predominates, at high HCO3 predominates
How is secretion of saliva regulated?
Regulated by neural control, sympathetic reduced, parasympathetic increased, can be congenital (taste), conditioned (pavlov)
What are the different types of motility in the abdomen?
Segmental- breakdown/mix, peristaltic- aboral direction
anti-peristaltic- oral direction
What is used for chemical breakdown in digestion?
ions, mucous, enzymes
What happens to chemicals after chemical breakdown?
What are the 4 muscles of the abdominal wall?
Rectus abdominus, external abdominal oblique, internal abdominal oblique and transverse abdominal
What is the insertion and origin of the rectus abdominis?
O- ventral surface of ribs
I- cranial pubis
How are the left and right side of the rectus abdomens separated?
What is the outermost abdominal wall muscle?
External abdominal oblique
What are the origins and insertions of the external abdominal obliques?
O- lateral caudal surface of ribs 4+/lumbodorsal fascia
I- linea alba/ pre-pubic tendon
What direction do external abdominal oblique muscle fibres run?
What is the order from outside to inside of transverse abdominal muscles?
External abdominal oblique, Internal abdominal oblique, Transverse abdominal
What is the origin and insertion of the internal abdominal oblique?
O- coxal tuber/lumbodorsal fascia
I- linea alba, last rib and cartilages of caudal ribs
What direction do fibres of the internal abdominal oblique run?
What is the origin and Insertion of the transverse abdominal?
O- medial ventral ribs/ deep lumbosacral fascia
I- linea alba
How do fibres of the transverse abdominal run?
How is the linea alba formed?
Tendons of lateral abdominal wall muscles pass above and below the rectus abdominis to join milling forming aponeurosis and the linea alba
What section of the spinal cord innervates the abdominal wall muscles?
T13 and L1-L5
How does the dorsal and ventral routes innervate the abdominal wall?
Dorsal roots- dorsal muscle
Ventral roots- 3 branches
1) medial between TA and IAO to RA
2) lateral between IAO/EAO to midway
3) lateral cutaneous perforates EAO to skin
What in the embryo does the epithelial lining and exocrine glands develop from?
What does muscle and connective tissue develop from in the embryo?
What does the foregut in the embryo develop into?
pharynx, oesophagus, stomach and initial duodenum