nutrition in animals
DESCRIPTION
Nutrition in Animals. Learning Objectives for Nutrition in Animals. Basic Biological Molecules Chemical Digestion The Human Alimentary Canal Absorption & Assimilation. Lesson Objectives. Different Biological Molecules Major Food Groups Food Tests. Biological Molecules. Food Groups - PowerPoint PPT PresentationTRANSCRIPT
Nutrition in Animals
Learning Objectives for Nutrition in Animals Basic Biological Molecules Chemical Digestion The Human Alimentary Canal Absorption & Assimilation
Lesson Objectives
Different Biological Molecules Major Food Groups Food Tests
Biological Molecules
Food Groups Food Tests Biological Molecules
Major Food Groups
Carbohydrates Proteins Fats
Food Test Demonstration
Starch (Iodine Test) Reducing Sugar (Benedict’s Solution
Test) Protein (Biuret Test) Fat (Ethanol Emulsion Test)
Food Tests
Starch (Iodine Test) Add Iodine to
sample.
Food Tests
Reducing Sugar (Benedict’s Solution Test)
Add Benedict’s Solution to sample. Boil mixture for no more than 2
minutes.
Food Tests
Protein (Biuret Test) Add Sodium Hydroxide (NaOH) to
sample. Add Copper II Sulphate (CuSO4) drop
by drop.
Food Tests
Fat (Ethanol Emulsion Test) Add Ethanol to sample and shake. Add Water to mixture and shake.
Biological Molecules
Water Carbohydrates Proteins Fats
Water
No one owes Singapore a living
Discuss with your partner and write on:
- the importance of water in our lives
- methods to conserve water at home/school
Basic Biological Molecules Chemical Digestion The Human Alimentary Canal Absorption & Assimilation
Learning Objectives for Nutrition in Animals
Lesson Objectives
Chemical Digestion Structure and Functions of Biological
Molecules
Reflection time…
DO NOT WASTE FOOD
Food for thought.
Carbohydrates
Carbohydrases breaks down carbohydrates into simple sugars (monosaccharide)
Polysaccharides=>Disaccharides =>Monosaccharides
Chemical Digestion
Carbohydrates
Examples of monosaccharide- glucose, fructose, galactose Examples of disaccharide- maltose, sucrose, lactose Examples of polysaccharide- starch (amylose, amylopectin), glycogen
Proteins
Proteases breaks down proteins into amino acids
Protein => Polypeptide => Amino acids
Chemical Digestion
Fats/Lipids
Lipases breaks down fats into glycerol and fatty acids
Lipid => Glycerol & Fatty Acids
Chemical Digestion
Revisiting the Carbohydrates
Examples of monosaccharide- glucose, fructose, galactose Examples of disaccharide- maltose, sucrose, lactose Examples of polysaccharide- starch (amylose, amylopectin), glycogen
Revisiting the Carbohydrates
Carbohydrases breaks down carbohydrates into simple sugars (monosaccharide)
Polysaccharides=>Disaccharides =>Monosaccharides
Chemical Digestion
Hydrolysis Reaction
Carbohydrates – Condensation RxnMonosaccharides=>Disaccharides
=>Polysaccharides
Condensation Condensation
Functions of Carbohydrates
Glucose is required for cellular respiration to provide energy.
Glycogen serves as an energy store.
Revisiting the Proteins
Proteases breaks down proteins into amino acids
Protein => Polypeptide => Amino acids
Chemical Digestion
Hydrolysis Reaction
Proteins – Condensation Rxn
Proteases breaks down proteins into amino acids
Amino Acid => Polypeptide => Protein
Condensation Weak bonding
Functions of Proteins
Amino acids are converted into protein to make protoplasm.
Enzymes are made of proteins. Antibodies are made of proteins. Excess amino acids are not stored and
will be removed via deamination in the liver.
Revisiting the Fats/Lipids
Lipases breaks down fats into glycerol and fatty acids
Lipid => Glycerol & Fatty Acids
Chemical Digestion
Hydrolysis Reaction
Functions of Fats/Lipid
Fat is required for the cell membrane. Adipose tissue helps to insulate the
body and keep the body warm. Adipose tissue also helps protect the
vital organs. Fats are energy store and can be
utilised for respiration to provide energy.
Summary for Nutrients
Hydrolysis reactions- A chemical reaction where a
large and complex molecule into 2 smaller and simple molecules.
- A molecule of water is used up in the process.
Condensation reactions- A chemical reaction where 2
simple molecules are joined together to form a larger and more complex molecule.
- A molecule of water is produced in the process.
Summary for Nutrients
e.g. glucose, galactose,
fructose
Carbohydrates
Polysaccharide
(complex sugar)
Disaccharide
(double sugar)
Monosaccharide
(simple sugar)
e.g. maltose, lactose, sucrose
e.g. starch, glycogen, cellulose
Summary for Nutrients
e.g. adenine,methionine
Proteins
ProteinsPolypeptide
Chains
Amino Acids
e.g. enzymes,antibodies
Summary for NutrientsFats
Fats/Lipids
Glycerol
Fatty Acids
e.g. adipose tissues,phospholipids
Basic Biological Molecules Chemical Digestion The Human Alimentary Canal Absorption & Assimilation
Learning Objectives for Nutrition in Animals
Lesson Objectives
Parts of the Human Alimentary Canal Functions of the Human Alimentary
Canal Peristalsis
The Human Alimentary Canal
Nutrition in Human
Human Alimentary CanalProcesses and Functions Ingestion – the process of taking in food into
the alimentary canal through the mouth.
Digestion - the process of the breaking down of large, complex and insoluble substances into small, simple and soluble molecules by the action of enzymes; so as to facilitate the absorption of nutrients into the body.
Human Alimentary CanalProcesses and Functions Absorption – the process where digested
food substances are taken up by the body through the blood stream.
Assimilation – the process where the nutrients absorbed are converted into new protoplasm and/or used to release energy for the body
Human Alimentary CanalProcesses and Functions Egestion – the process where indigestible
and unabsorbed material are removed from the alimentary canal through the anus.
Egestion = Excretion*
*Excretion is the removal of metabolic waste products from the body through the excretory system (to be covered in later topics)
Buccal Cavity Food is broken down into
smaller bits by chewing (physical digestion).
- increases surface area of food substances.
Salivary glands produce salivary amylase that breaks down starch into maltose.
The bolus is swallowed and being pushed along the oesophagus by peristalsis.
Salivary glands
OesophagusSalivary amylase
Starch → Maltose
Peristalsis
Peristalsis
Longitudinal muscles
Epidermal layer
Lumen
Circular muscles
Antagonistic muscles
Stomach Gastric juices is secreted into the stomach.
Gastric juices contain hydrochloric acid, pepsin and rennin.
- hydrochloric acid kills bacteria.- hydrochloric acid lowers the pH
in the stomach (pH 2~3).- pepsin breaks down protein to
polypeptides.- rennin curdles the milk.- salivary amylase action stops
due to the low pH. (non-optimal pH conditions)
Pepsin Protein → Poly-peptides
Small intestine and peripheral organs Liver makes bile
Bile is stored in gall bladder and secreted into the duodenum via the bile duct.
- bile increases the pH (pH 9~10)- bile emulsifies fat. - emulsification of fat increases
the surface area for fat digestion.
- lipases will break down the fats into fatty acid and glycerol.
Liver
Gall bladder
Pancreas
Bile duct
Duodenum
Lipase Fats → Fatty acid + Glycerol
Small intestine and peripheral organs Pancreas produces pancreatic
juices. Pancreatic juices are secreted
into the duodenum via the pancreatic duct.
- pancreatic juices increases the pH (pH 9~10).
- pancreatic juices contains pancreatic amylase, pancreatic lipase, and trypsin.
- trypsin breaks down protein to polypeptides.
- gastric juices actions stop.
Liver
Gall bladder
Pancreas
Bile duct
Duodenum
Trypsin Protein → Poly-peptides
Small intestine and peripheral organs Small intestine produces
intestinal juices. Small intestine absorbs most of
the nutrients at the end of ileum.
- intestinal juices contains erepsin, lipases and carbohydrases.
- erepsin breaks down polypeptides into amino acids.
Liver
Gall bladder
Pancreas
Bile duct
Duodenum
ErepsinPoly-peptides → Amino acids
Large intestine, rectum and anus.
Colon absorbs the remaining water content and mineral salts.
Rectum serves as a temporary storage for indigestible material and unabsorbed material.
The anus is the opening where faeces is egested out of the body.
colon
rectum
anus
appendix
Starch maltose Protein polypeptides Fat fatty acids and glycerol
amylase
trypsin
lipase
Digestion (pancreatic enzymes)
Maltose glucose Polypeptides amino acids Fats fatty acids and glycerol
maltase
erepsin
lipase
Digestion (intestinal enzymes)
Basic Biological Molecules Chemical Digestion The Human Alimentary Canal Absorption & Assimilation
Learning Objectives for Nutrition in Animals
Lesson Objectives
Absorption of nutrients Roles of the liver
Absorption of nutrients
Nutrients absorbed in the Digestive System would be carried to parts of the body via the Circulatory System (Blood).
Adaptations in the Alimentary Canal The Human Alimentary Canal (from the mouth to the
anus) is approximately 6.5 metres long. Why?
-Food takes time to be digested.
-The longer food stays in the body, more nutrients can be absorbed.
Adaptations in the Alimentary Canal
folds
Increased surface area can help increase the rate of absorption of nutrients.
The intestinal walls are lined with networks of blood capillaries.
Adaptations in the Alimentary Canal
folds
Diagram of a villus showing the blood capillary network and the lacteal.
Blood capillaries
Lacteal
microvilli
The hepatic portal vein
Nutrients absorbed from the small intestine is transported to the liver via the hepatic portal vein
Nutrients absorbed from the large intestine is transported to the liver via the hepatic portal vein
Roles of the Liver
Metabolism of Glucose Metabolism of Amino Acid (Formation of
Urea) Metabolism of Fats Breakdown of Red Blood Cells Breakdown of Alcohol Production of heat.
Metabolism of Glucose Insulin and Glucagon are secreted
by the pancreas to regulate the blood glucose levels in the body.
In a healthy individual, insulin is secreted when blood-glucose level is high.
- Insulin promotes the uptake of glucose into the liver and the conversion of glucose into glycogen.
In a healthy individual, glucagon is secreted when blood-glucose level is low.
- Glucagon promotes the conversion of glycogen into glucose and the release of glucose into the bloodstream.
Insulin will promote the conversion of glucose into glycogen in the liver
Glucagon will promote the conversion of glycogen
into glucose in the liver
Metabolism of Amino Acids Excess amino acids will be found in
the human body after the person has taken in large amount of protein.
The excess amino acids will be deaminated to form urea.
Urea is toxic and is removed from the body via the kidney.
Urea is a metabolic waste product.The liver will deaminate excess
amino acids to form urea.
Breakdown of Alcohol Alcohol is broken down in the liver
into harmless substances through detoxification.
When there is surplus of nutrients in the body, alcohol is converted into fats and stored in the body.
When there is a shortage of nutrients in the body, alcohol is broken down by enzymes to release energy.
The liver will detoxify alcohol to form otherharmless products.
Summary of Digestion
Carbohydrates(polysaccharides)
Glucose(monosaccharides)
e.g. Glycogen(polysaccharides)
Proteins(polypeptides)
Amino Acids(monomers)
e.g. Enzymes(polypeptides)
Fats/Lipids(polymer)
Fatty Acids/Glycerol(monomers)
e.g. Adipose Tissue(polymers)
DIGESTION
ASSIMILATION
File Case 00129042009
Annabel: found dead at home in her room by her mother at 3pm.
Suspect 1: Joanne (Annabel’s mother)
Recently divorced, Status complicated
Has depression and suicidal tendency
Suspect 2: Nicholas (Annabel’s brother)
Studies at SARS University:
Life-Sciences undergrad, specializing in toxins
On bad terms with Annabel, Sibling rivalry.
Suspect 3: Bruce (Joanne’s boyfriend)
Bought all the food ate by Annabel before she died.
Annabel finds him unworthy of her mother.
Coroner’s Report
Cause of death: Acute food poisoning due to presence of neurotoxin produced by
mutant bacterial strain; Mutant bacterial strain is similar to Pseudoalteromonas tetraodonis,
a well-known marine bacterium that produces a neurotoxin that is very potent, usually found in puffer fish and other venomous marine animals.
Other evidences gathered
Unpublished blog posting from Annabel. Recorded statements from suspects. Preliminary food test results. Food test results for the presence of mutant bacterial strains.
(currently in progress)
Directives:
1. Which are the food product/s that should be tested for the presence of the mutant bacterial strain?
2. Which are the food product/s likely to be utilized by the mutant bacterial strain for its metabolism?
3. Suggest a possible reason for the observation in the Iodine test performed on the food samples collected from the body of the deceased.
3. Suggest a possible reason for the observation in the Iodine test performed on the food samples collected from the body of the deceased.
Directives:
4. Examine the results for the food test for presence of mutant bacterial strain so as to determine the cause of acute food poisoning.
5. Suggest who might be responsible for poisoning Annabel, indicating the contaminated food item, and support your deduction with logical reasoning.