BIOL10004 Lecture Notes - Lecture 18: Autotroph, Heterotroph, Vitamin A
What nutrients do animals need?
Autotroph: require only inorganic compounds absorbed from environemnt to
synthesize complex organic compounds
-
Heterotroph: cant synthesize organic compounds from inorganic molecules need to
ingest
-
Carbs - main energy source
-
Lipids - energy and structural component of cells
-
Protein - energy as well as amino acids for protein synthesis
-
Essential amino acids
-
Essential fatty acids
-
Vitamins: organic elements essential for metabolism
Obtained from food
○
Humans have 13 essential
○
Needed in trace amounts
○
Fat soluble: A, D, E, K
○
Water-soluble: B, C
○
-
Minerals: inorganic elements essential for metabolism
Trace acmounts Fe Cu I F Se
○
High amounts: Na Cl K Ca P Mg S
○
-
Water
-
Factors which affect an animal's nutrient requirements
Metabolic rate depends on activity, body mass, environmental conditions
-
Metabolic rate and mass-specific metabolic rate
Mass-specific metabolic rate
Size plays big role in metabolic rate
Big animals need more energy
□
BUT, per unit of body mass, small animals need more energy
□
§
Small animals
Need more food per unit body mass
□
Need more energy-rich food
□
§
○
-
What is digestion?
Breakdown of large molecules into smaller ones
-
Eventually molecules are small enough to be absorbed across gut wall to provide
energy
-
Mechanical and enzymatic digestion
-
Digestive systems
Simple systems
○
-
Pathway and enzymes
Buccal cavity (mouth) + salivary glands
Physical breakdown by MASTICATION
Diff teeth for diff foods□
§
Mixing with saliva
Lubrication□
Enzymatic breakdown: amylase digest starch□
§
○
Pharynx and oesophagus
Oral and nasal cavities meet
§
Transports food to stomach via PERISTALSIS
§
○
Stomach
Mechanical breakdown - muscular walls churn food
§
Chemical breakdown
Acidic (HCl, pH 1-2)□
Enzymes: pepsin and other proteases -digest proteins + lipases□
§
Food reduce to chyme
§
Pyloric sphincter moves chyme to duodenum
§
○
Small intestine
Duodenum, jejenum, ileum
§
Enzymatic digestion
Intestinal wall secretes enzymes - mainly for sugars □
Pancreatic fluid: Pepsin, trypsin, lipase, amylase□
Bile: from liver via gall bladder - emulsifies fat - lipases□
§
Absorption of nutrients into bloodstream (diffusion and active
transport)
§
Large SA (villi) - faster absorption
§
○
-
Large intestine
Caecum
Blind-ended pouch at start of large intestine □
Digestion of cellulose by bacteria □
§
Colon
Removal of water□
Formation of faeces□
Elimination through anus□
§
○
Specialisation based on diet
Composition of food
Plants as food
Mostly carbs
§
Some unsaturated lipids
§
Little proteins
§
Easy to catch but hard to digest (low in nutrients)
§
ADAPTATION: long complex digestive tracts
§
○
Animals as food
Mostly protein
§
Some saturated lipids
§
Little carbs
§
Easy to digest but hard to catch
§
Gluconeogenesis: production of glucose from proteins + other materials
§
ADAPTATION:
Gluconeogenesis□
Short simple digestive tracts □
§
○
-
Carnivore (lion)
Protein high
○
Teeth for puncturing, tearing and shearing
○
Short, simple digestive tract
○
-
Omnivore (chimpanzee)
Fruits and plants - also hunts
○
Teeth for biting, chewing, grinding
○
Similar to carnivore tract
○
Not as efficient at digesting particular foods - but greater variety
○
-
Herbivore (elephant)
Plants
○
Teeth for prying (tusks) and grinding
○
Long digestive tract
○
Digest cellulose helped by bacteria
○
-
Cellulose: in plant cell walls - no vertebrates have enzyme cellulase
-
Digestive processes of monogastric herbivores:
Foregut (bacteria, protists) fermentation
Sac containing protists and bacteria
§
Microbes use glucose from cellulose digestion + release short-chain fatty
acids -> absorbed by animal
§
Microbes are source of protein -> can be digested along tract
§
Eg. Sheep, cattle, hippos
§
Ruminants (sheep, cattle, etc.) regurgitate and re-chew food
Organisms that ferment food as foregut fermenters using a
specialised series of stomachs prior to further digestion and
regurgitation
□
§
○
-
Hindgut (bacteria) fermentation
Only microbes
§
In large caecum and proximal colon
§
Microbes cant be digest - lost protein
§
Can digest nutrients absorbed by animal first - not lost to microbes
§
Eg. Horse, koala, pigs, rabbit
§
○
Caecotrophy: ingestion of caecal faeces for nutritional purposes
Microbial protein in faeces
§
Eat and redigest pellets for max nutrition
§
Ant afford to lose protein when diet is low in quality
§
In RABBITS + SMALL RODENTS
§
○
Vitamin imbalance
Rickets
Soft bones
○
Vitamin D deficiency
○
Affects Ca2+ uptake
○
-
Scurvy
Bleeding, skin spots, loss of teeth
○
Disruption of collagen synthesis
○
Vitamin C deficiency
○
-
Hypervitaminosis A:
Varied symptoms
○
Increased bone turnover - affects metabolism of other vitamins
○
Vitamin A excess
○
-
Mineral deficiency
Goitre
Swelling of thyroid/neck
○
Iodine deficiency
○
Prevent by dietary intake of iodine
○
Still occurs in India, central Africa, central Asia
○
-
Digestion
Wednesday, 30 May 2018
2:49 pm
What nutrients do animals need?
Autotroph: require only inorganic compounds absorbed from environemnt to
synthesize complex organic compounds
-
Heterotroph: cant synthesize organic compounds from inorganic molecules need to
ingest
-
Carbs - main energy source
-
Lipids - energy and structural component of cells
-
Protein - energy as well as amino acids for protein synthesis
-
Essential amino acids
-
Essential fatty acids
-
Vitamins: organic elements essential for metabolism
Obtained from food
○
Humans have 13 essential
○
Needed in trace amounts
○
Fat soluble: A, D, E, K
○
Water-soluble: B, C
○
-
Minerals: inorganic elements essential for metabolism
Trace acmounts Fe Cu I F Se
○
High amounts: Na Cl K Ca P Mg S
○
-
Water
-
Factors which affect an animal's nutrient requirements
Metabolic rate depends on activity, body mass, environmental conditions
-
Metabolic rate and mass-specific metabolic rate
Mass-specific metabolic rate
Size plays big role in metabolic rate
Big animals need more energy
□
BUT, per unit of body mass, small animals need more energy
□
§
Small animals
Need more food per unit body mass
□
Need more energy-rich food
□
§
○
-
What is digestion?
Breakdown of large molecules into smaller ones
-
Eventually molecules are small enough to be absorbed across gut wall to provide
energy
-
Mechanical and enzymatic digestion
-
Digestive systems
Simple systems
○
-
Pathway and enzymes
Buccal cavity (mouth) + salivary glands
Physical breakdown by MASTICATION
Diff teeth for diff foods□
§
Mixing with saliva
Lubrication□
Enzymatic breakdown: amylase digest starch□
§
○
Pharynx and oesophagus
Oral and nasal cavities meet
§
Transports food to stomach via PERISTALSIS
§
○
Stomach
Mechanical breakdown - muscular walls churn food
§
Chemical breakdown
Acidic (HCl, pH 1-2)□
Enzymes: pepsin and other proteases -digest proteins + lipases□
§
Food reduce to chyme
§
Pyloric sphincter moves chyme to duodenum
§
○
Small intestine
Duodenum, jejenum, ileum
§
Enzymatic digestion
Intestinal wall secretes enzymes - mainly for sugars □
Pancreatic fluid: Pepsin, trypsin, lipase, amylase□
Bile: from liver via gall bladder - emulsifies fat - lipases□
§
Absorption of nutrients into bloodstream (diffusion and active
transport)
§
Large SA (villi) - faster absorption
§
○
-
Large intestine
Caecum
Blind-ended pouch at start of large intestine □
Digestion of cellulose by bacteria □
§
Colon
Removal of water□
Formation of faeces□
Elimination through anus□
§
○
Specialisation based on diet
Composition of food
Plants as food
Mostly carbs
§
Some unsaturated lipids
§
Little proteins
§
Easy to catch but hard to digest (low in nutrients)
§
ADAPTATION: long complex digestive tracts
§
○
Animals as food
Mostly protein
§
Some saturated lipids
§
Little carbs
§
Easy to digest but hard to catch
§
Gluconeogenesis: production of glucose from proteins + other materials
§
ADAPTATION:
Gluconeogenesis□
Short simple digestive tracts □
§
○
-
Carnivore (lion)
Protein high
○
Teeth for puncturing, tearing and shearing
○
Short, simple digestive tract
○
-
Omnivore (chimpanzee)
Fruits and plants - also hunts
○
Teeth for biting, chewing, grinding
○
Similar to carnivore tract
○
Not as efficient at digesting particular foods - but greater variety
○
-
Herbivore (elephant)
Plants
○
Teeth for prying (tusks) and grinding
○
Long digestive tract
○
Digest cellulose helped by bacteria
○
-
Cellulose: in plant cell walls - no vertebrates have enzyme cellulase
-
Digestive processes of monogastric herbivores:
Foregut (bacteria, protists) fermentation
Sac containing protists and bacteria
§
Microbes use glucose from cellulose digestion + release short-chain fatty
acids -> absorbed by animal
§
Microbes are source of protein -> can be digested along tract
§
Eg. Sheep, cattle, hippos
§
Ruminants (sheep, cattle, etc.) regurgitate and re-chew food
Organisms that ferment food as foregut fermenters using a
specialised series of stomachs prior to further digestion and
regurgitation
□
§
○
-
Hindgut (bacteria) fermentation
Only microbes
§
In large caecum and proximal colon
§
Microbes cant be digest - lost protein
§
Can digest nutrients absorbed by animal first - not lost to microbes
§
Eg. Horse, koala, pigs, rabbit
§
○
Caecotrophy: ingestion of caecal faeces for nutritional purposes
Microbial protein in faeces
§
Eat and redigest pellets for max nutrition
§
Ant afford to lose protein when diet is low in quality
§
In RABBITS + SMALL RODENTS
§
○
Vitamin imbalance
Rickets
Soft bones
○
Vitamin D deficiency
○
Affects Ca2+ uptake
○
-
Scurvy
Bleeding, skin spots, loss of teeth
○
Disruption of collagen synthesis
○
Vitamin C deficiency
○
-
Hypervitaminosis A:
Varied symptoms
○
Increased bone turnover - affects metabolism of other vitamins
○
Vitamin A excess
○
-
Mineral deficiency
Goitre
Swelling of thyroid/neck
○
Iodine deficiency
○
Prevent by dietary intake of iodine
○
Still occurs in India, central Africa, central Asia
○
-
Digestion
Wednesday, 30 May 2018
2:49 pm
What nutrients do animals need?
Autotroph: require only inorganic compounds absorbed from environemnt to
synthesize complex organic compounds
-
Heterotroph: cant synthesize organic compounds from inorganic molecules need to
ingest
-
Carbs - main energy source
-
Lipids - energy and structural component of cells
-
Protein - energy as well as amino acids for protein synthesis
-
Essential amino acids
-
Essential fatty acids
-
Vitamins: organic elements essential for metabolism
Obtained from food
○
Humans have 13 essential
○
Needed in trace amounts
○
Fat soluble: A, D, E, K
○
Water-soluble: B, C
○
-
Minerals: inorganic elements essential for metabolism
Trace acmounts Fe Cu I F Se
○
High amounts: Na Cl K Ca P Mg S
○
-
Water
-
Factors which affect an animal's nutrient requirements
Metabolic rate depends on activity, body mass, environmental conditions
-
Metabolic rate and mass-specific metabolic rate
Mass-specific metabolic rate
Size plays big role in metabolic rate
Big animals need more energy □
BUT, per unit of body mass, small animals need more energy □
§
Small animals
Need more food per unit body mass□
Need more energy-rich food □
§
○
-
What is digestion?
Breakdown of large molecules into smaller ones
-
Eventually molecules are small enough to be absorbed across gut wall to provide
energy
-
Mechanical and enzymatic digestion
-
Digestive systems
Simple systems
○
-
Pathway and enzymes
Buccal cavity (mouth) + salivary glands
Physical breakdown by MASTICATION
Diff teeth for diff foods
□
§
Mixing with saliva
Lubrication
□
Enzymatic breakdown: amylase digest starch
□
§
○
Pharynx and oesophagus
Oral and nasal cavities meet
§
Transports food to stomach via PERISTALSIS
§
○
Stomach
Mechanical breakdown - muscular walls churn food
§
Chemical breakdown
Acidic (HCl, pH 1-2)
□
Enzymes: pepsin and other proteases -digest proteins + lipases
□
§
Food reduce to chyme
§
Pyloric sphincter moves chyme to duodenum
§
○
Small intestine
Duodenum, jejenum, ileum
§
Enzymatic digestion
Intestinal wall secretes enzymes - mainly for sugars □
Pancreatic fluid: Pepsin, trypsin, lipase, amylase□
Bile: from liver via gall bladder - emulsifies fat - lipases□
§
Absorption of nutrients into bloodstream (diffusion and active
transport)
§
Large SA (villi) - faster absorption
§
○
-
Large intestine
Caecum
Blind-ended pouch at start of large intestine □
Digestion of cellulose by bacteria □
§
Colon
Removal of water□
Formation of faeces□
Elimination through anus□
§
○
Specialisation based on diet
Composition of food
Plants as food
Mostly carbs
§
Some unsaturated lipids
§
Little proteins
§
Easy to catch but hard to digest (low in nutrients)
§
ADAPTATION: long complex digestive tracts
§
○
Animals as food
Mostly protein
§
Some saturated lipids
§
Little carbs
§
Easy to digest but hard to catch
§
Gluconeogenesis: production of glucose from proteins + other materials
§
ADAPTATION:
Gluconeogenesis□
Short simple digestive tracts □
§
○
-
Carnivore (lion)
Protein high
○
Teeth for puncturing, tearing and shearing
○
Short, simple digestive tract
○
-
Omnivore (chimpanzee)
Fruits and plants - also hunts
○
Teeth for biting, chewing, grinding
○
Similar to carnivore tract
○
Not as efficient at digesting particular foods - but greater variety
○
-
Herbivore (elephant)
Plants
○
Teeth for prying (tusks) and grinding
○
Long digestive tract
○
Digest cellulose helped by bacteria
○
-
Cellulose: in plant cell walls - no vertebrates have enzyme cellulase
-
Digestive processes of monogastric herbivores:
Foregut (bacteria, protists) fermentation
Sac containing protists and bacteria
§
Microbes use glucose from cellulose digestion + release short-chain fatty
acids -> absorbed by animal
§
Microbes are source of protein -> can be digested along tract
§
Eg. Sheep, cattle, hippos
§
Ruminants (sheep, cattle, etc.) regurgitate and re-chew food
Organisms that ferment food as foregut fermenters using a
specialised series of stomachs prior to further digestion and
regurgitation
□
§
○
-
Hindgut (bacteria) fermentation
Only microbes
§
In large caecum and proximal colon
§
Microbes cant be digest - lost protein
§
Can digest nutrients absorbed by animal first - not lost to microbes
§
Eg. Horse, koala, pigs, rabbit
§
○
Caecotrophy: ingestion of caecal faeces for nutritional purposes
Microbial protein in faeces
§
Eat and redigest pellets for max nutrition
§
Ant afford to lose protein when diet is low in quality
§
In RABBITS + SMALL RODENTS
§
○
Vitamin imbalance
Rickets
Soft bones
○
Vitamin D deficiency
○
Affects Ca2+ uptake
○
-
Scurvy
Bleeding, skin spots, loss of teeth
○
Disruption of collagen synthesis
○
Vitamin C deficiency
○
-
Hypervitaminosis A:
Varied symptoms
○
Increased bone turnover - affects metabolism of other vitamins
○
Vitamin A excess
○
-
Mineral deficiency
Goitre
Swelling of thyroid/neck
○
Iodine deficiency
○
Prevent by dietary intake of iodine
○
Still occurs in India, central Africa, central Asia
○
-
Digestion
Wednesday, 30 May 2018 2:49 pm
Document Summary
Autotroph: require only inorganic compounds absorbed from environemnt to synthesize complex organic compounds. Heterotroph: cant synthesize organic compounds from inorganic molecules need to ingest. Lipids - energy and structural component of cells. Protein - energy as well as amino acids for protein synthesis. High amounts: na cl k ca p mg s. Metabolic rate depends on activity, body mass, environmental conditions. But, per unit of body mass, small animals need more energy. Eventually molecules are small enough to be absorbed across gut wall to provide. Eventually molecules are small enough to be absorbed across gut wall to provide energy. Enzymes: pepsin and other proteases - digest proteins + lipases. Intestinal wall secretes enzymes - mainly for sugars. Bile: from liver via gall bladder - emulsifies fat - lipases. Absorption of nutrients into bloodstream (diffusion and active transport) Easy to catch but hard to digest (low in nutrients) Gluconeogenesis: production of glucose from proteins + other materials.