Human Body Test 2 Flashcards
What structures are part of the G.I. tract?
Mouth, pharynx, oesophagus stomach, small and large intestine, rectum and anus
What are the accessory organs of digestion?
Salivary, glands, teeth, liver, gallbladder, and pancreas
What is digestion?
The process by which food is broken down into smaller particles, suitable for absorption
What is absorption?
The process, whereby the end products of digestion move across the walls of the digestive track into the blood and lymph for distribution throughout the body
What is mechanical digestion?
The breakdown of large food particles into smaller pieces by physical means (chewing)
What is chemical digestion?
The chemical alteration of food
What is the purpose of the digestive system?
To break down our digestive food into particles that are small and simple enough to be absorbed
What are the four layers of the digestive track?
- Mucosa.
- Sub mucosa.
- Muscle Layer
- Serosa.
What is the mucosal layer of the digestive tract?
- Innermost layer
- Consists of mucus membrane, some connective tissue and smooth muscle
- Folded to increase surface area for absorption
- Glands secrete, mucus digestive enzymes, and hormones
- Concern with digestion and absorption
What is the submucosa layer?
-Thick layer of loose connective tissue
-lies beneath the mucosa
-Contains blood vessels, nerves, glands, and lymphatic vessels
What is the muscle layer?
-Responsible for various movements in the digestive tract
-Alternate contraction and relaxation of stomach muscles, digest food mechanically, and mix the particles with digestive juices (segmentation)
-Peristalsis: squeeze the food from behind and push it forward
-Responsible for swallowing and defaecation
What is the serosa layer?
-Outermost lining
-Extensas paratonia membranes, mass century mesocolon, omentum, large flat fold is structures that perform important functions
What do the paratonia membranes in the serosa layer of the digestive track help do?
Help anchor of the digestive organs in place. They carry blood vessels, lymph us cells and nerves to the abdominal organs and help restrict the spread of infection in the abdominal cavity.
Describe the structure and function of the mouth
This is where the digestive tract begins. Food is ingested into the mouth, which is lined with mucous membranes and contain structures that assist in the digestive process.
Describe the structure and the function of the teeth
-To chew food and begin mechanical digestion
-Breaks down large pieces of food to smaller ones and moistens the secretions in the mouth of
What are the three parts of a tooth?
The crown, the neck and the root
Describe the structure in the function of the tongue
Muscular organ that occupies floor of the mouth
- Facilitates, chewing, and swallowing by repositioning food in the mouth
-The tongue pushes the food which is moulded into a ball like mass towards the pharynx
-Contains taste buds, which allow you to taste food
Describe the structure and the function of the salivary glands
-Three pairs secrete their contents into the mouth
What are the three pairs of salivary glands?
-The parotid
-Submandibular
-Sub lingual glands
What is the function of the parotid gland?
-Largest glands
- Can get infected by mumps
-Lie below and anterior to the ears
What are the submandibular glands?
-located on the floor of the mouth under the tongue
-Smallest of the glands
-Exocrine glands that secrete saliva
-Contains saliva
What is saliva?
-Watery fluid that contains mucus and a digestive enzyme
-Reaches the most by way of tiny ducts
-Soften, and moisten food
Describe the structure and the function of the hard and soft palates
-These form the roof of the mouth
- Anterior hard palate separates the oral cavity from the nasal passages
-The posterior soft palate separates the oral cavity from the nasal pharynx
What is the function of the uvula?
- Prevents food and water from entering the nasal passages during the active swallowing