animal nutrition - wikispacesbio5090.wikispaces.com/file/view/nutrition+1.pdf · animal nutrition...
TRANSCRIPT
ANIMAL NUTRITION
Animal Nutrition
Nutrients & Diet Digestive System
Lesson 1Learning Objective1.List the chemical elements which make up carbohydrates, fats and
proteins.2.List the principle sources of, and dietary importance of carbohydrates,
fats, proteins, vitamins (C and D), mineral salts (calcium and iron), fibre (roughage) and water.
Outline Need for food Carbohydrates Fats Proteins
Need for Food
•To provide energy for vital activities of body•To replace energy lost•To make new cells and tissues•To repair tissues•To maintain healthy body•To prevent deficiency diseases
7 Classes of Food
•Carbohydrates•Fats•Proteins•Vitamins•Dietary fibre•Mineral Salts•Water
Carbohydrate
Sources:
Carbohydrate
Uses of carbohydrates:• Source of energy (17 kJ/g)• Formation of nucleic acids (DNA)• To be converted to other organic
compounds, e.g. amino acids and fats• Formation of supporting structures, e.g.
cellulose cell wall.
Carbohydrate
Chemical elements:• Carbon (C)• Hydrogen (H)• Oxygen (O)
Carbohydrate
Carbohydrate
Monosaccharide PolysaccharideDisaccharide
E.g. glucose, fructose, galactose
E.g. starch,glycogen,cellulose
E.g. maltose, lactose, sucrose
Monosaccharide
Disaccharide
Polysaccharide
Stored food• In animals, glucose is stored in the form of glycogen.• In plants, glucose is stored in the form of starch.
Why are glycogen and starch suitable as storage materials?
– Easily hydrolysed to glucose when needed– Large molecules and insoluble in water hence they do not
change the osmotic pressure in cells– Structures are compact so they occupy less space
Fats
Sources:
Fats
Uses of fats:• Source of energy (37 kJ/g)• Insulating material to prevent
excessive heat loss• Prevent water loss from skin's
surface, by producing oily secretions over the surface.
• A solvent for fat-soluble vitamins and hormones
Fats
Chemical elements:• Carbon (C)• Hydrogen (H)• Oxygen (O)
Fats
Fats
Chemical elements:• Carbon (C)• Hydrogen (H)• Oxygen (O)
Fats
Fats
Saturated Unsaturated
Fats that contain fatty acid chains
with only single bonds
Fats that contain fatty acid chains
with doublesingle bonds
Saturated Fats
• Sources: Meats, dairy products, chips.• Not heart-healthy• Can raise LDL cholesterol (“bad”
cholesterol)
Unsaturated Fats
• Sources: Nuts, avocadoes, olives• Heart-healthy• Can lower LDL cholesterol (“bad”
cholesterol) and raise HDL cholesterol (“good” cholesterol)
Proteins
Sources:
Proteins
Uses of proteins:• Source of energy (17 kJ/g)• Synthesis of new protoplasm• Synthesis of enzyme and hormone• Synthesis of antibodies to combat
diseases
Proteins
Chemical elements:• Carbon (C)• Hydrogen (H)• Oxygen (O)• Nitrogen (N)• Sulphur (S)• Phosphorus (P)
ProteinsProteins are comprised of amino
acids linked together.
There are 20 different amino acids used to make proteins.
Amino acids can be broken into 2 types:• Essential amino acids (8)– Amino acids that cannot be synthesised by human body.
• Non-essential amino acids (12)– Amino acids that can be synthesised by human body.
ProteinsDeficiency:Kwashiorkor
Signs and symptoms:• Swollen abdomen• Enlarged liver• Changes in pigmentation of skin and hair• General drowsiness• Cracked and scaly skin
Learning Objective
1.List the chemical elements which make up carbohydrates, fats and proteins.
2.List the principle sources of, and dietary importance of carbohydrates, fats, proteins, vitamins (C and D), mineral salts (calcium and iron), fibre (roughage) and water.