Chapter 21: Nutrition And Digestion Flashcards
Animals fall into one of _____ categories
4
All animals are what
Heterotrophs
Herbivores eat what
Autotrophs
Carnivores eat what
Other heterotrophs
Omnivores eat
Both plants and animals
Detritivores
Eat decomposing organisms
What are the states of animals digesting their food
1) ingestion
2) digestion
3) absorption
4) Elimination
Earthworms, birds, and grasshoppers have what
Crop and gizzard
Crop
Stores the food
Gizzard
Grinds the food
Where does digestion begin
In the mouth
Saliva does what
Moistens and lubricates food
Saliva contains what
Antibacterial agent and amylase
What is the tongue function
Tongues folds the food in the mouth into bolus and moves it toward the pharynx
Epiglottis
Small flap of tissue that prevents bolus of food from going into the trachea
What moves food through peristalsis
Esophagus
Peristalsis
Rhythmic waves of smooth muscle contractions
Chyme
A mixture of partially digested food and gastric juice
What bacteria lives in our stomach
H pylori
H pylori
Bacteria that causes ulcers
Digestion and nutrient absorption occur where
Small intestine
Small intestine consist of
Duodenum, jejunum, and ileum
Duodenum is responsible for
Digestion
Jejunum and ileum are responsible for
Absorption
Duodenum
Where chyme mixes with digestive juices from the pancreas liver and gallblader
Accessory organs include
Salivary glands, gall bladder, liver and pancreas
Pancreas
Produces pancreatic juices containing digestive enyzymes- all four macromolecules & bicarbonate
Bicarbonate
Neutralizes acidic chyme, making it slightly basic, and its a buffer
Pancreas produces what hormones
Insulin and glucagon
Insulin and glucagon control
Blood glucose levels
What happens when eating a carbohydrate rich meal
Glucose level increases in blood, beta cells of pancreas produce insulin, glucose becomes converted to glycogen in liver and skeletal muscles
Insulin- decreased concentration of glucose in blood
When fasting or exercising what happens to glucose levels`
Decreases, gamma cells of pancreas to produce glucagon, glycogen becolmnes broken down in liver and skeletal muscles,
Glucagon - increase concentration of blood level
Liver produces what
Bile
Bile is stored where
Gallbladder until needed
Bile
Neither hormone or enzyme and bile salts breaks up fat into small droplets that are more susceptible to attack by lipases
Lipases
Chemically digest lipids
Pancreases produces whaat digestive enzymes
Pancreatic amylase, trypsin, chymotrypsin, nucleases, and lipase
Small intestine produces
Maltase, sucrase, lactase, various peptidases
Carbohydrates are digested where
In the mouth and small intestine
Carbs are digestive by what
Salivary amylase (in the mouth) and pancreatic amylase, maltase and sucrase (small intestine)
Proteins are digested where
In the stomach and small intestine
Proteins are digested by what
Pepsin (in stomach) and trypsin, chymotrypsin and various peptidases (in small intestine)
Lipids are digested where
Small intestine
Lipids are digested by what
Bile and lipase
Nucleic acids are digested where
Small intestine
Nucleic acids are digested by what
Nucleases: dnase and rnase in small intestine
Epithelial wall is covered with (small intestine)
Villi
Villi
Fingerlike projections which in turn are covered by microvilli
Microvilli and villi
Greatly increases surface area for absorption
Underneath and within villi are
Lymph and blood vessels
Fatty acids and glycerol recombine
Into fats which become coated with proteins and transported into the lymph vessels
Absorption of amino acids and monosaccharides
AA and monosaccharides pass out of intestinal epithelium into blood vessels that take them into liver for modification
Liver receives most what
Products of digestion except fats
Liver functions
Converts glucose to glycogen, stores detoxifies substances make some proteins and produce bile
What happens in large intestine
Unabsorbed food and undirected food materials move from the ileum to large intestine
What from the large intestine attaches to the appendix
Cecum
Large intestines functions by
Absorbing water, vitamins, and prepares feces for expulsion
Does large intestine digest food
No, not in humans
What three areas does food do not digest (in humans_
Pharynx, esophagus, large intestine
How can digestive systems adapt to different diets
The digestive systems of animals have evolved to fit their diets
Herbivores have longer _______ and larger _____ than carnivores (helps with the digestion of cellulose)
Digestive tract and cecum
What animals have a four chambered stomach
Cattle, deer, and sheep
What are the 4 chambered stomach
Rumen, reticulum, omasum, and abomasym
Rumen
Contains cellulose digestive bacteria
Abodmasum
The stomach that produces gastric juices
Essential nutrients cannons be made
From raw materials
What are 4 classes of essential nutrients
Essential fatty acids, essential amino acids, vitamins, and minerals
Essential fatty acids
Used to make phospholipids of cell membranes and internal membrane
Where are fatty acids found
Found in seeds, grains, and vegetables
Essential amino acids
Used to make proteins
Where are essential amino acids found
Meats, eggs, and mild
Vitamins
Organic nutrients that are essential for us but in small amounts
What are two types of vitamins
Water soluble vitamins and fat soluble vitamins
Minerals
Inorganic nutrients other than C, O, H and N
3 important minerals
Calcium, phosphorus, and iron
Balanced diets helps what
Animals function efficiently
What does a balanced diet contain
40% carbs
30% proteins
30%fats
What kind of diets can be harmful
Fat diets
1 kcal =
1 cal = 1 calories
How many servings should we eat of variety of fruits and vegetables daily
Five or more
