digestive system Flashcards
what is the buccal cavity made of
teeth
tounge
pallete
what happens in buccual cavity
saliva binds find together
salivary amylase digests startch to maltose
mineral salts - regulates pH around 7
what is saliva made of
mucin
what enzyme is secreted in buccal cavity
amlyase
what is the function of the digestive system
large organic masses are broken down into smaller particles the body can use as fuel
what is the function of buccal cavity - mechanical
mechanical digestion and chewing takes place
what is the function of the buccal cavity - chemical reaction
saliva in the mouth consists of mucin
salivary amylase digests startch to maltose
mineral salts regulates pH to 7
how does proportions of layers of the gut wall differ
folding of mucosa - less in oesophagus
more in ileum
what is defenition of chemical digestion
breakdown of large molecules into small soluble molecules using enzymes
what is defenition of mechanical digestion
cutting action of the teeth followed by the rhythmic contraction of the gut
what is oesophagus lined with
mucous membrane
function of mucus
protects the lining of the stomach from digestion by protease
stops friction
helps peristalsis
4 parts of the colon
ascending
transverse
descending
sigmoid
5 bits of the gut lining
mucosa
submucosa
circular muscle
longitudinal muscle
serosa
function of mouth
mechanical digestion, moistened by saliva
salaiva includes enzyme amylase which breaks down startch into maltose
mucus binds food together and lubricates it
oesophagus function
bolus is pushed down by peristalsis
what is peristalsis
localised contraction of circular muscles
what is peristalsis
localised contraction of circular muscles
what enzymems do pancrease secrete
amylase
lipase
trypsin
what does stomache do
churns the bolus with gastric juices to form chyme
absorbs water and fat soluble substances such as alcohol
what makes stomach acidic
HCL
optimum pH for for pepsin to work and kills bacteria
function of pancrease
secretes pancreatic juice, enters duodenum thrugh pancreatic duct
where is the bile produced
liver
where is bile stored
gall bladder
function of bile
emulsify large globules of fat into tiny droplets so they have a larger srface area for lipase to work
secondary function of bile
helps to neutralise acidity of the food from the stomach
what to rwtchan in abot liver
bile
what does the walls of the duodenm contain
secretes alkaline juice and mucus
what does duodenum do
enzymes on the vili complete digestion
maltase
endopeptidases
what is ileum adapted for
absorption
what are on the vili of ileum
epithelial cells with microscopic projections called microvili
what does microvili do
increase surface area of the cell membrane of the epithelial cells for absorption
what is there a lot of in microvili
mitochondria
what happens in the colon
water and minerals absorbed
bacteria lives there responsible for making vit K and folic acid
