Animal Nutrition Flashcards
The five processes of the alimentary canal
Ingestion, Digestion, Absorption, Assimilation, Egestion
Definition of Alimentary Canal in mammals
Made up of a system of organs that each perform a specific function
Organs that form the Alimentary Canal
Mouth, Oesophagus, Stomach, Small intestine, Large Intestine, Anus
Accessory organs
Pancreas, Liver, Gallbladder, Salivary Glands, Teeth
Organs using Chemical Digestion
Stomach, Small intestine, Mouth Cavity
Organs using Mechanical Digestion
Oesophagus, Stomach, Teeth
Function of oesophagus
Moves food from mouth to stomach using peristalsis
Functions of stomach
Continues mechanical Digestion and mixes food with digestive juices through peristalsis
Secretes digestive juices essential for chemical Digestion
Functions of small intestine
Secretes digestive juices for final part of chemical digestion
Duodenum digests chemically
Ileum absorbs nutrients
Functions of large intestine
Caecum: Receives waste material from ileum
Colon: Absorbs water from indigestible food in Alimentary Canal
Rectum: Stores faeces prior to excretion
Function of Anus
Passes faeces out of organism
Function of pancreas
Secretes pancreatic juice that contains enzymes
Function of gallbladder
Stores bile from liver before it is secreted into duodenum of small intestine
Function of liver
Produce and secretes bile that helps to break down fat
Salivary Glands
Secretes saliva that contains enzymes
Function of mouth cavity
Receives food that is ingested
Begins mechanical digestion by tongue and teeth
Chemical digestion starts by saliva
Function of teeth
Used for chewing food (mastication)
How many pairs are there of Salivary Glands and what is the function of saliva?
3 pairs of Salivary Glands
Saliva moistens food and helps it stick together making it easier to swallow
What is a bolus and which organ helps form it?
A bolus is a food ball formed by the tongue mixing food with saliva
4 kinds of teeth and their functions
- Incisors - Sharp and chisel shaped. Used for biting and cutting.
- Canines - Sharp and cone shaped. Used for tearing.
- Premolars - Blunt, ridged and Broad surface area. Used for grinding, chewing, crushing.
- Molars - Blunt, ridged, Broad surface area (larger than premolars). Used for grinding, chewing and crushing.
Human dental formula
2.1.2.3
_______
2.1.2.3
Why is food chewed into smaller pieces?
The smaller the piece, the larger the surface area that becomes available for enzymes to act on.
What prevents food from entering the lungs and choking?
A cartilage flap (epiglottis) closes the opening of the trachea to the lungs
2 layers of muscular walls in oesophagus
Inner layer - consists of circular muscles
Outer layer - Longitudinal muscle counteracts
What is the sphincter?
A ring of smooth muscle that prevents good from returning to oesophagus and is found at the end of oesophagus.
Process that moves food along the alimentary canal to the Anus
Peristalsis
What is bile, where is it produced and where is it stored?
Bile is a greenish - yellow substance that is produced by liver and stored in the gallbladder.
What is acid chyme?
Semi-digested food that passes from stomach to small intestine
When is bile released?
When acid chyme flows from the small intestine, the gallbladder is stimulated to release bile.
The functions of bile
- The emulsification of fats and lipids. This increases the surface area of fats, making it easier for lipase enzymes to digest them.
- Neutralises acid chyme from stomach.
What is dentition?
The type, number and arrangement of teeth in the mouth of a specific species of animals.
Dental formula for herbivores and how are their teeth adapted?
0.0.3.3.
________
3.1.3.3
Insicors- sharp to cut off plant material
Canines- often absent
Molars and premolars- large and flat, grind plant material.
What do we call the chewing of food
Mastication
What fluids does saliva contain?
Mucus and the enzyme amylase
Name the 2 muscles that contract during peristalsis and which layer they will be (inner or outer)
Circular muscle - inner layer
Longitudinal muscle- outer layer
Explain the process of peristalsis
- The circular muscle contracts behind the bolus,pushing it down the oesophagus
- The longitudinal muscles contracts in front the bolus making the oesophagus shorter and wider ahead of the bolus .
What prevents the food from coming back up the oesophagus?
The sphincter
The process of breaking down large fat molecules into smaller ones
Emulsification
What does Emulsification do?
Increases the surface area of the fats,which makes it easier for lipase enzymes to digest them.
True or false
Bile is an alkaline that neutralizes acid chyme
True
When are the digestive enzymes most effective?
In a slightly alkaline medium
Hard bone -like structures used for bitting,chewing and grinding?
Teeth
What does the process of chewing require?
The movement of the lower jaw and teeth
Protein molecules that act as catalyst in the biochemical reactions
Enzymes
What does the saliva secreted by the salivary glands contain?
Mucus, H²O and carbohydrate enzymes
What pH level does a slightly alkaline saliva keep in the mouth?
7,4
What does the carbohydrase enzyme change starch into?
Maltose
What do the gastric glands in the stomach wall secrete? And what about substance made out of?
The secrete gastric juice which are made out of , H²O,mucus enzymes and HCL
Enzymes in gastric juices are ?
Proteases
What is a process of absorption and where does it take place
The diffusion of small soluble digested molecules enter the bloodstream and takes place in the ileum (which is the second part of the intestine)
