Lecture 8 Adaptation: Nutrition Among Animals (Part II)

• Enzyme for Digestion of Carbohydrates in the Oral Cavity

  Salivary amylase

  • secreted by salivary glands of some herbivorous mollusks, insects, and primates (mammals)
  • breaks down disaccharides, oligosaccharides, and starch in the oral cavity
  • absent in saliva of carnivores
• Other Secretions in the Oral Cavity of Animals

  A) toxin

  
• Digestive Tract

  A) mouth

  B) esophagus

  C) deglutition

  D) peristalsis

  E) segmentation

  
• Esophagus

  A) propels

  B) crop

  C) temporary

  D) birds

  
• Stomach

  A) denticles

  B) chambers

  
• Insect

  A) proventriculus

  
• Stomach

  A) ruminants

  B) abomasum

  C) bacteria

  D) rennin

  
• Stomach

  A) single

  B) protein

  
• Stomach

  A) cardia

  B) fundus

  C) corpus

  D) pylorus

  E) sphincter

  
• Stomach

  A) rugae

  B) 2-4

  C) chyme

  
• Stomach

  A) Hydrochloric

  B) inactive

  C) Pepsin

  D) protein

  E) HCl

  F) B12

  G) absorption

  H) HCl

  
• Small Intestine

  A) digestion

  B) absorption

  C) absent

  D) typhlosole

  E) infolding

  
• Small Intestine

  A) villi

  B) microvilli

  
• Small Intestine

  Segments of small intestine among vertebrates

  • duodenum - connected to the stomach
  • jejunum - middle segment and usually the longest
  • ileum - distal segment connected to the cecum
• Small Intestine

  • food enters the duodenum upon opening/relaxation of the pyloric sphincter
  • secretions of accessory glands liver and pancreas aid in final digestion of food
  • site of absorption of digested food such as monosaccharides (simple sugars like glucose, fructose, galactose), amino acids, fatty acids and monoglycerides
• Small Intestine

  • the duodenum is stimulated by entry of acidic chyme to produce two hormones into the blood:
  • Secretin - stimulates the exocrine pancreas to secrete a large volume of fluid with high bicarbonate (HCO3-) content
  • Cholecystokinin (CCK) - stimulates the exocrine pancreas to secrete proenzymes or zymogens
• Accessory Organs for Digestion in Vertebrates

  Pancreas - secretes digestive enzymes and bicarbonate, which neutralizes the acidity of food coming in from the stomach

  Liver - secretes bile, which is temporarily stored and concentrated at the gall bladder
• Accessory Gland for Digestion: Pancreas

  A) zymogens

  B) insulin

  C) sugar

  
• Pancreatic Enzymes

  A) enterokinase

  B) trypsin

  
• Liver (Note: the descriptions given below are that of a primate,

  particularly human liver)

  largest mass of glandular tissue in the body

  this has right and left lobes, quadrate and caudate lobes
• Liver

  A) bile

  B) cholesterol

  C) 1L

  D) plasma

  E) hepatic

  
• Large Intestine

  A) undigested

  B) reabsorption

  
• Nutritional Requirements

  A) ATP

  B) nitrogen

  C) Mineral salts

  
• Malnutrition

  A) Kwashiorkor

  B) Marasmus

  
• Nutritional Requirements

  A) carotene

  
• Nutritional Requirements

  A) folic acid

  
• Nutritional Requirements

  A) ascorbic acid

  
• Antioxidant - a substance that protects the cell from damaging effects of free radicals

  Coenzyme - is an organic non-protein compound that binds with enzyme to catalyze reactions.

  Cofactor - is a non-protein chemical that assists in a biological reaction. This can be metal ion, organic compound, or other chemicals.

  Zymogen - is the inactive form of an enzyme