Stomach and rumen Flashcards
What is the principal of hox genes ?
hox gene sequence on the DNA is in the same order in which they are used from head to tail and changes in hox genes cause valves , sphincter changes in diameter and function
What structures derive from the foregut section of the gut tube ?
oral cavity , tongue
oesophagus
stomach
duodenum
upper and lower resp tract
liver
pancreas
tonsils , salivary glands
thyroid
thymus
anterior pituitary
What structures in the adult derive from the midgut section of the gut tube ?
rest of small intestine and part of large intestine
What structures of the adult derive from the hindgut part of the gut tube ?
rest of large intestine
Where does the gut tube derive from ?
forms from endoderm which then forms the epithelial lining of the digestive tract and parts of liver and pancreas
What does the mesoderm form in terms of the gut tube ?
mesoderm forms muscular and peritoneal components of the gut
what does the gut tube develop from ?
ventral invaginations at either end of the embryo that elongate and fuse along the ventral midline to form straight tube
What is mesentery ?
fold or membrane that has bv , nerves and lymphatics to and from visceral structures
What does mesentery refer to ?
mesojenjunum
What does greater omentum refer to ?
greater omentum that supports the stomach also known as the mesogastrium
Name developmental defects
-viteline fistula
-viteline cyst
-meckels diverticulum
-umbilical hernia due to faulty closure of abdominal wall leaves larger opening
-clefts - abnormal growth processes e.g hernia , spina bifida ( split vertebral column ) , schistosoma reflexum ( open body wall and dislocation of organs ) palatoschisis ( cleft lip and palate )
-aplasia - absence of part or all of an organ
-hypoplasia - reduced development of an organ
What is the septum transversum ?
junction between amniotic ectoderm and yolk sac endoderm
Describe the factors that regulate appetite in domestic species
-age - slower metabolism as get older
-environment - stress fight/ flight
-exercise - lifestyle
- multi- animal household - compete for food
-repro status pregnant/lactating
-genetics - no POMC gene - overeat
-type food
-hormones
outline hormones that stimulate appetite
ghrelin
neuropeptide Py
agouti-related peptides
Name appetite decreasing hormones
leptin
peptide YY
glucagon like peptide
What happens to the gastrointestinal sphicter under parasympathetic control
relaxes - decreases retention allows food to move through GI tract
What happens to gastrointestinal sphincter under sympathetic control ?
contraction of the gastrointestinal sphicters - increase retention and stop movement of food through GI tract
What are the splanchnic nerves ?
-thoracic - sympathetic , supply abdomen and pelvis ,greater splanchnic ( stomach , spleen, liver , pancreas , gallbladder , adrenal medulla ) , lesser splanchnic ( midgut ) , Least splanchnic nerve ( renal plexus ) , arise T1-L2 enter coeliac plexus
- pelvic - parasympathetic , reg emptying of bladder ( opening and close urethral sphincter ) ,innervates repro organs , motility to rectum , arise from s2-4 enter sacral plexus
Parasympathetic supply in abdomen
- originate from vagus nerve
-ventral vagus plexus - liver and stomach - hepatic branches form plexus at liver to cystic duct,gal bladder , l lateral lobe of liver and bile duct
- dorsal vagal trunk p– cardiac region of stomach - forms plexus to pylorus