Chapter 41 Animal Nutrition

Front 1

1. What are the 3 categories animals fall into and define each?

Back 1

a. herbivore, carnivore, omnivore

b. Herbivores; eat mainly plants and algae
Carnivores; eat other animals
Omnivores; regularly consume animals as well as plants and algae

Front 2

2. What must an animal's diet provide?

Back 2

a. chemical energy, which converted into ATP to power cellular work
b. organic building blocks, to synthesize variety of organic molecules
c. essential nutrients as required by cells and must be obtained from dietary sources

Front 3

3. What are the four classes of essential nutrients?

Back 3

a. essential amino acids
b. essential fatty acids
c. vitamins
d. minerals

Front 4

4. Essential amino acids

Back 4

- require 20 amino acids and 11 body produces and 9 come from diet

- meat, eggs, and cheese provide all the essential amino acids and are complete proteins

- most plant proteins are incomplete in amino acids composition

Front 5

5. Essential fatty acids

Back 5

- can synthesize most of the fatty acids they need

- must be obtained from the diet and include certain unsaturated fatty acids

Front 6

6. Vitamins

Back 6

- organic molecules required in the diet in small amounts
- 13 vitamins are essential for humans
- fat-soluble and water-soluble vitamins

Front 7

7. Minerals

Back 7

- simple inorganic nutrients, usually required in small amounts

- ingesting large amounts of some minerals can upset homeostatic balance like sodium

Front 8

8. What is malnourisment?

Back 8

- a dietary deficiency long-term absence from the diet of one or more essential nutrients

Front 9

9. What can happen with deficiencing in Essential Nutrients?

Back 9

- can casue deformities, disease and death

Front 10

10. What is undernutrition and what are the effects?

Back 10

a. results when a diet does not provide enough chemical energy

b. use up stored fat and carbs, break down its own proteins, lose muscle mass, suffer protein deficiency of the brain and dier or suffer irreversible damage

Front 11

11. What are the 4 stages of food processing?

Back 11

Ingestion, Digestion, Absorption, Eliminiation

Front 12

12. Suspension feeders

Back 12

- sift small food particles from the water

Front 13

13. Substrate feeders

Back 13

- live in or on their food source

Front 14

14. Fluid feeders

Back 14

- suck nutrient-rich fluid from a living host

Front 15

15. Bulk feeders

Back 15

- eat relatively large pieces of food

Front 16

16. Describe the process of digestion

Back 16

a. digestion is the process of breaking food down into molecules small enough to absorb

b. Mechanical digestion, including chewing, increases the surface area of food

c. Chemical digestion splits food into small molecules that can pass through membranes;

d. the process of enzymatic hydrolysis splits bonds in molecules with addition of water

e. absorption is uptake of nutrients by body cells

f. elimination is the passage of undigested material out of the digestive system

Front 17

17. What is the function of digestive compartments?

Back 17

- reduce the risk of an animal digesting its own cells and tissues

Front 18

18. How does intracellular digestion work?

Back 18

- food particles are engulfed by phagocytosis

- food vacuoles, containing food, fuse with lysosomes containing hyrolytic enzymes

Front 19

19. What is extracellular digestion and where does it occur?

Back 19

a. breakdown of food particles outside of cells

b. it occurs in compartments that are continuous with the outside of the animal's body

Front 20

20. What is gastrovascular cavity and its function?

Back 20

a. a cavity where extracellular digestion takes place

b. functions in both digestion and distribution of nutrients

Front 21

21. What is alimentary canal and its function?

Back 21

a. digestive tube with two openings, a mouth and anus on more complex animals

b. have specialized regions that carry out digestion and absorption in a stepwise fashion

Front 22

22. Describe the mammalian digestive system and list the accessory glands.

Back 22

a. mammalian digestive system consists of an alimentary canal and accessory glands that secrete digestive juices through ducts

b. salivary glands, the pancreas, the liver, and the gallbladder

Front 23

23. What is peristalsis and what is its role?

Back 23

a. rhythmic contractions of muscles in the wall of the canal

b. food is pushed along

Front 24

24. What are sphincters?

Back 24

- valves that regulate the movement of material between compartments

Front 25

25. Draw the schematic diagram of digestive process.

Back 25

mouth -> salivary glands -> esophagus -> stomach -> gallbladder, liver, pancreas -> small intestine -> large intestine -> rectum -> anus

Front 26

26. Describe the first stages of digestion.

Back 26

- first stage is mechanical and takes place in the oral cavity
- salivary glands deliver saliva to lubricate food
-teeth chew food into smaller particles that are exposed to salivary amylase enzyme, that breaksdown glucose polymers
- saliva also contains mucus, a viscous misture of water, salts, cells and glycoproteins
- toungue shapes food into a bolus and provides help with swallowing
-throat or pharynx, is the juction that opens to bother the esophagus and the trachea

Front 27

26. Describe the first stages of digestion continued

Back 27

-esophagus connects to the stomach
-trachea (windpipe) leads to the lungs
-peristalsis in esophagus takes food down from the pharynx to stomach
-swallowing causes the epiglottis to block entry to the trachea, and the bolus is guided by the larynx, the upper part of the respiratory tract
-coughing occurs whent he swallowing reflex fails and food or liquids reach the windpipe

Front 28

27. Describe the digestion process in the stomach

Back 28

- stomach stores food and secretes gastric juice, which converts a meal into acid chyme
-gastric juice has a low pH of about 2, which kills bacteria and denatures proteins; is made up of HCl and pepsin
- pepsin is a protease a protein digesting enzyme that cleaves proteins into smaller peptides

Front 29

27. Describe the digestion process in the stomach (continued)

Back 29

- parietal cells secrete hydrogen and chloride ions separately into the lumen of the stomach
-chief cells secrete inactive pepsinogen, which is activated to pepsin when mixed with HCl in the stomach
-mucus protects the stomach lining from the gastric juice

Front 30

28. What cause gastric ulcers?

Back 30

- bacterium Heliobacter pylori

Front 31

29. Explain stomach dynamics

Back 31

- coordinated contraction and relaxation of stomach muscle churn the stomach's contents

- sphincter prevent chyme from entering the esophagus and regulate its entry into the small intestine

Front 32

30. Explain first portion of digestion in the small intestine.

Back 32

- small intestine is the longest section of the alimentary canal and is the major organ of digestion and absorption

- the first portion of the small intestine is the duodenum, where chyme from the stomach mixes with digestive juices from the pancreas, liver, gallbladder and the small intestines itself

Front 33

31. Pancreatic secretions

Back 33

- produces protease trypsin and chymotrypsin that are activated in the lumen of the duodenum

- solution is alkaline and neutralizes the acidic chyme

Front 34

32. Bile production by the liver

Back 34

- bile added by liver aids in digestion and absorption of fats
-bile is made in the liver and stored in the gallbladder
-bile also destroys nonfunctional red blood cells

Front 35

33. Secretions of the small intestine

Back 35

- epithelium lining of the duodenum produces several digestive enzymes
- enzymatic digestion is completed as peristalsis moves the chyme and digestive juices along the small intestine
-digestion occurs in the duodenum; the jejunum and ileum function mainly in absorption of nutrients and water

Front 36

34. Absorption in the small intestine

Back 36

- small intestine has a huge surface are, due to villi and microvilli that are exposed to the intestinal lumen
- enormous microvillar surface creates a brush that greatly increases the rate of nutrient absorption
-transport across the epithelial cells can be passive or active depending on the nutrient
- hepatic portal vein carries nutrient-rich blood from the capillaries of the villi to the liver, then to the heart

Front 37

34. Absorption in the small intestine continued

Back 37

- regulates nutrient distribution interconverts many organic molecules, and detoxifies many organic molecules
- epithelial cells absorb fatty acids and monoglycerides and recombine them into triglycerides
-these fats are coated with phospholipids, cholesterol and proteins to form water-soluble chylomicrons
-chylomicrons are transported into a lacteal, a lymphatice vessel in each villus
-lymphatic vessels deliver chylomicron-containing lymph to large veins that return blood to the heart

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35. Absorption in the large intestine

Back 38

- colon of the large intestine is connected to the small intestine
-cecum aids in the fermentation of plant material and connects where the small and large intestines meet
-human cecum has an extension called the appendix, which plays a very minor role in immunity

Front 39

36. Function of the colon

Back 39

- recover water that has entered the alimentary canal
-houses bacteria like E. Coli which live on unabsorbed organic material; some produce vitamins
-feces, including undigested material and bacteria, become more solid as they move through the colon
feces are stored in the rectum until they can be eliminated through the anus
-two sphincters between the rectum and anus control bowel movements

Front 40

37. Dental adaptations

Back 40

- dentition, an animal's assortment of teeth, structural variation reflect diet
-success of mammals is due in part to their dentition
-nonmammalian vertebrates have less specialized teeth

Front 41

38. Stomach and intestinal adaptations

Back 41

- carnivores have large, expandalbe stomachs
- herbivores and omnivores generally have longer alimentary canals than carnivore, to digest vegetation

Front 42

39. Mutualistic adaptations

Back 42

- herbivores have fermentation chambers, where mutualistic microorganisms digest cellulose
-Ruminants

Front 43

40. How is digestion regulated?

Back 43

- each step of digestive system is activated as needed
- intestinal part of the nervous system helps to regulate the digestive process
- endocrine system also regulates digestion

Front 44

42. How energy storage is regulated?

Back 44

- body stores energy-rich molecules that are not needed right away for metabolism
-in humans, energy is stored fist in the liver and muscle cells in the polymer glycogen
-excess energy is store in adipose tissue, the most space-efficient storage tissue

Front 45

43. Explain Glucose Homeostasis

Back 45

- hormones insuline and glucagon regulate the breakdown of glycogen into glucose
- liver is the site for glucose homeostasis
- carb-high meal raises insulin levels, triggers the systhesis of glycogen
-low blood sugar causes glucagon to stimulate the breakdown of glycogen and release glucose

Front 46

44. Describe how appetite and consumption is regulated.

Back 46

- overnourishment causes obesity, which results from excessive intake of food energy with excess stored as fat
-obesity contributes to diabetes, cancer of the colon and breasts, heart attacks, and strokes
-hormones regulate long-term and short-term appetite by affecting the satiety center in the brain
-leptin is produced by adipose tissue and can help to suppress appetite

Front 47

45. Draw schematic of digestive system.

Back 47

draw.