Digestive system Flashcards
what is the alimentary canal?
gastrointestinal tract: is the muscular tube that extends from the mouth to the anus . it includes the mouth , pharynx , esophagus , stomach , small intestine , and large intestine .
what are the accessory digestive organs ?
organs that secrete saliva , bile , and digestive enzymes that all contribute to the break down of food . these organs are not part of the alimentary canal but are part of the digestive system . accessory digestive organs include : salivary glands , gallbladder , liver , and pancreas .
what are cheeks formed by?
buccinator muscle that is covered with skin and lined with mucous membrane .
what is the vestibule?
area between gums and cheek
how many deciduous teeth do humans have ?
20
how many permenant teeth do we have?
32
what are the parts of the tooth?
crown :exposed part , formed of dentine covered by enamel
neck: middle part
root: lies within the alveolar processes (dentine covered by cementum ) and connected to alveolar bone with periodontal ligament
pulp cavity : located within the dentine and contains nerves , vessels
what is the rough surface of the tongue called and why is it rough?
the dorsal surface is rough because it contains papillae (taste receptors
what is the smooth surface of the tongue ?
the ventral surface is anchored to the floor of the mouth through the frenulum
list the 3 salivary glands .
- ) parotid gland
- )sublingual gland
- ) submandibular gland
describe the parotid gland .
1.) parotid gland : largest salivary gland , located anterior to the auricle , duct opens into vestibule of mouth opposite to the upper 2nd molar tooth.
describe the sublingual gland .
2.)sublingual gland : smallest , located below the tongue , has multiple ducts
describe the submandibular gland.
3.) submandibular gland : placed near the base of the mandible , duct opens into the mouth cavity on either side of the frenulum of the tongue
what are faces ?
constricted parts between nasopharynx and oropharynx , a ring of lymphoid tissue lies at this junction
what is the esophagus’ muscular wall formed by?
both skeletal and smooth muscle fibers
what are the 3 parts the esophagus ?
cervical
thoracic
abdominal
where does the esophagus naturally constrict?
at its beginning ,
where is is crossed by the left bronchi
and at the diaphragmatic hiatus
where is the stomach located ?
left hypocondrium and epigastrium
where does the eosophagus end and the stomach start?
the cardiac orifice
what is the region above the cardiac orifice?
the fundus
what part of the stomach includes the antrum and canal and ends in duodenum?
pylorus
what is the simple epithelium inside the stomach called?
mucosa
describe the muscles inside the stomach.
has 3 layers of smooth muscles . muscle is thickened at the pyloric end to form pyloric sphincter .
describe the structure of the small intestines
mucosa is thrown into circular folds , and it posses villi
what are the main parts of the small intestine ?
duodenum
jejunum
ileum
describe the structure of the duodenum .
c shaped with pancreases in its curvature . divided into 4 main parts . bile duct and main pancreatic duct open on the major duodenal papilla .
it digests food through the action of pancreatic enzymes and bile .
describe the structure of the jejunum .
middle part , is 2.5 m in length
describe the structure of the ileum,
3.5m in length , less number of circular folds , has peers patches. absorbs carbohydrates , proteins and fats .
where are the ileum and jejunum suspended from?
the posterior wall of the abdominal wall by a fold of peritoneum called mesentery
what is the liver?
largest gland in the human body . it lies in the right hypochondriac and epigastrium and consists of 2 lobes
what is the gall bladder?
muscular secreting in a shallow depression on the liver . stores and dumps bile into duodenum through bile duct .
