Digestive system Flashcards
Adaptations for Nutrition
What does the palate do for the digestive system?
Separates the breathing and feeding pathways, allowing both processes to go on simultaneously.
What does the tongue do for the digestive system?
Manoeuvres food for chewing and rolls food into bolus for swallowing. Mixes food with saliva.
What do the teeth do for the digestive system?
Cut and grind food so that solid foods are reduced to smaller particles for swallowing, and the food has a larger surface area for enzyme action.
What does the buccal cavity do for the digestive system?
The mouth cavity contains the tongue, teeth and the opening of the salivary gland ducts.
What does the epiglottis do for the digestive system?
Muscular flap which reflexively closes the trachea during swallowing to prevent food entry to respiratory tract.
What does the oesophagus do for the digestive system?
A muscular tube which lies dorsal to the trachea and connects the buccal cavity to the stomach. Peristalsis occurs here.
What does the liver do for the digestive system?
An accessory organ which produces bile and stores it in the gall bladder.
What does the bile duct do for the digestive system?
Carries bile from gall bladder to duodenum.
What does the gall bladder do for the digestive system?
Stores bile (produced in liver)
What does the stomach do for the digestive system?
A muscular sac with an inner layer that produces enzymes. Its role is to store and digest food, especially protein. Other glands in the wall produce mucus to prevent this organ being digested by its own enzymes.
What does the duodenum do for the digestive system?
The first 30cm of the small intestine. Receives pancreatic secretions and bile and produces alkaline mucus for protection, lubrication and chyme neautralization.
What does the pancreas do for the digestive system?
A large gland situated below the stomach which produces a secretion called pancreatic juice. This secretion contains proteases to digest proteins, lipase to digest lipids and amylase to digest starch.
What does the ileum do for the digestive system?
A long muscular tube (up to 6m). Food digested by enzymes produced in the wall. The inner walls are folded into villi, the surface of which is further increased by microvilli. It is the main site for absorption of soluble products of digestion.
What does the colon do for the digestive system?
Absorbs water forming drier and thicker faeces. Mucus glands present provide lubrication.
What does the appendix do for the digestive system?
No function in humans. It is a vestige of the caecum in other mammals (herbivores).
