Digestive system Flashcards
The four digestive processes explained
Ingestion – The process of taking food into the body.
Digestion – The process of breaking down food into its component parts in the stomach and small intestine.
Absorption – Occurs in the small intestine and large intestine – the process of transferring nutrients from the intestine into the bloodstream.
Excretion – Removal of indigestible material as faeces.
Order of the digestive tract
Oral Cavity
Oropharynx
Oesophagus
Stomach
Duodenum
Jejunum
Ileum
Caecum
Colon
Rectum
Anus
Name the four accessory digestive structures
Salivary Glands,
Liver,
Gall Bladder,
Pancreas
Describe four functions of the oral cavity
- Picking up food with the lips and tongue.
- Chewing to break up food into smaller boluses to aid swallowing.
- Lubrication of food with mucus and saliva.
- Digestion of carbohydrates in the mouth by salivary amylase (omnivores and herbivores only).
six functions of the tongue
- To aid ingestion
- To carry receptors for taste
- To form a bolus from food for swallowing
- Grooming
- Thermoregulation – flattening of the tongue and increased blood supply to the capillaries of the tongue allows saliva to evaporate and cooling of the body.
- Vocalisation – complex movements of the tongue allow an animal to vocalise.
The tongue is made of (1) allowing complex voluntary movement, with its root attached to the (2)
Striated muscle
Hyoid bone
the membrane which covers the gums is known as
the gingival membrane
incisor shape and function
small, chisel shaped with single root
Used for nibbling, cutting and grooming
Canine shape and function
pointed, curved, single root
grasping, gripping and piercing prey
Molar and pre molar
premolar<3>molar roots
Flatter surface with cusps
Shearing flesh with cusps,
flattened surfaces used for crushing and grinding.
saliva - structure and source
consists of 99:1 water:mucus
produced in salivary glands
function of soft palate
divide the naso/oro-pharynx
What system is the tonsil part of and what is its function
lymphatic system - protects the animal from disease
five steps of swallowing
- Food is rolled into a bolus by the tongue and is passed to the back of the mouth.
- The muscles of the pharynx contract, pushing the food bolus to the osophagus
- The epiglottis closes, preventing food entering the larynx.
- A wave of peristalsis pushes food down the osophagus.
- The epiglottis opens allowing respiration to begin again.
Function and location of esophagus
The osophagus carries food from the pharynx to the stomach. It lies dorsal and slightly to the left of the trachea. As it passes through the thorax it runs through the mediastinum, dorsal to the heart and between the lungs.
oesophogus structure
The osophagus is a tubular structure containing longitudinal and circular bands of smooth muscle. It is lined by stratified squamous epithelium.
structure and location of stomach within body
The stomach is a c-shaped sac-like organ which lies on the left side of the abdomen. it lies caudal to the diaphragm and cranial to the liver