chapter 41: animal nutrition

Question 1

What does an animals diet provide?

Answer 1

• chemical energy, which is converted into ATP, to power cellular processes
• organic building blocks, organic carbon and organic nitrogen to synthesize a variety of organic molecules

Question 2

What are the four classes of essential nutrients?

Answer 2

1. essential amino acids
2. essential fatty acids
3. vitamins
4. minerals

Question 3

How are essential fatty acids obtained?

Answer 3

include certain unsaturated fatty acids

Question 4

How are vitamins obtained?

Answer 4

fat-soluble and water-soluble

Question 5

What is scurvy?

Answer 5

a severe vitamin C deficiency
the symptoms include:
- anemia
- bone pain
- easy bruising
- swelling
- gum disease

Question 6

What are the vegetables and fruits with highest in vitamin C?

Answer 6

1. guavas
2. kiwi
3. bell peppers
4. strawberries

Question 7

What are the four different main feedings?

Answer 7

1. suspensions feeding: sift small food particles from the water
2. substrate feeding: animals that live in or on their food sources
3. fluid feeding: suck nutrient-rich fluid from a living host
4. bulk feeding: eat relatively large pieces of food

Question 8

What is digestion?

Answer 8

the process of breaking food down into molecules small enough to absorb

Question 9

What are the main stages of food processing?

Answer 9

• enzymatic hydrolysis splits bonds in molecules with the addition of water

Question 10

What is absorption?

Answer 10

the uptake of nutrients by body cells

Question 11

What is elimination?

Answer 11

passage of undigested material out of the digestive system

Question 12

What is intracellular digestion?

Answer 12

food particles are engulfed by phagocytosis

Question 13

What is extracellular digestion?

Answer 13

• the breakdown of food particles outside of cells
• digestive tube is called a complete digestive tract or alimentary canal

Question 14

What does the mammalian digestive system consist of?

Answer 14

1. an alimentary canal
2. accessory glands
   - salivary glands
   - pancreas
   - liver
   - gallbladder

Question 15

What is peristalsis?

Answer 15

food getting pushed along by rhythmic contractions of muscles in the wall of the canal

Question 16

What are sphincters?

Answer 16

valves that regulate movement of material between compartments

Question 17

How does food get to the stomach?

Answer 17

1. oral cavity: salivary glands deliver saliva to lubricate food, teeth chew with salivary amylase initiating breakdown of glucose
2. the tongue shapes food into a bolus and provides help with swallowing
3. the throat or pharynx is the junction that opens to both the esophagus and the trachea
4. esophagus conducts food from pharynx down to the stomach using peristalsis
5. swallowing causes the epiglottis to block entry to the trachea

Question 18

How does digestion in the stomach happen?

Answer 18

1. stomach stores food and begins digestion of proteins, it secretes gastric juice (made up of hydrochloric acid and pepsin)
2. parietal cells secrete hydrogen and chloride ions separately into the stomach lumen
3. mucus protects the stomach lining from gastric juice

Question 19

How does digestion in the small intestine happen?

Answer 19

• small intestine is the longer section of alimentary canal
• first portion of small intestine is the duodenum where chyme from the stomach mixes

Question 20

What are the pancreatic secretions?

Answer 20

-pancreas produces proteases trypsin and chymotrypsin that are activated

Question 21

What is the bile production by the liver importance?

Answer 21

• bile aids in digestion and absorption of fats
• bile is made in the liver and stored in the gallbladder
• bile destroys nonfunctional red blood cells

Question 22

What secretions happen in the small intestine?

Answer 22

• enzymatic digestion is completed as peristalsis moves chyme and digestive juices along small intestine
• most digestion occurs in duodenum
• small intestine has huge surface area due to villi and microvilli , creating a brush border that greatly increases rate of nutrient absorption

Question 23

What are the absorptions in the large intestine?

Answer 23

• colon is attached to small intestine
• cecum aids fermentation of plant material
• human cecum has appendix
• colon recovers water that has entered alimentary canal
• feces becomes more solid as it moves
• feces are stored in the rectum until they are eliminated

Question 24

What are stomach and intestinal adaptations?

Answer 24

• many carnivores have large and expandable stomachs
• herbivores and omnivores have longer alimentary canals, reflecting the longer time needed to digest vegetation

Question 25

What are mutualistic adaptations?

Answer 25

some intestinal bacteria produce vitamins, intestinal bacteria also regulate the development of the intestinal epithelium and function of the innate immune system

Question 26

What are mutualistic adaptations in herbivores?

Answer 26

many herbivores have fermentation chambers where cellulose is digested
ruminants is the elaborate adaptations for herbivorous diet

Question 27

What is glucose homeostasis?

Answer 27

• hormones insulin and glucagon regulate breakdown of glycogen into glucose
• happens in liver
• carbohydrate-rich meal raises insulin levels, triggering synthesis of glycogen
• low blood sugar causes glucagon to stimulate breakdown of glycogen and releases glucose