Chapter 33: Animal Nutrition Flashcards
What is animal nutrition?
the process by which an organism takes in, takes apart, and takes up food
What do herbivores dine on?
plants and algae
What do carnivores eat?
animals
What does it mean when an animal is an oppurtunistic feeder?
eating foods outside their standard diets when their usual foods aren’t available
A nutritionally adequete diet satisfies what needs?
1.) Chemical energy for cellular processes (cellular respiration)
2.) Organic builiding blocks for carbohydrate and other macromolecules
3.) Essential nutrients
Due to the fact that animals are heterotrophs they must obtain what organic precursors for biosynthesis?
1.) Organic carbons (such as sugar)
2.) Organic nitrogen (usually amino acids from the digestion of protein)
What are essential nutrients?
the materials that an animal’c cells require but cannot synthesize
What are the four classes of essential nutrients?
1.) Essential amino acids
2.) Essential fatty acids
3.) Vitamins
4.) Minerals
What is meant by a complete protein? Where can you get these?
An animal product such as meat, eggs, or chese that provides all of the essential amino acids.
What are they type of essential fatty acids that the human body cannot make?
Unsaturated, meaning that they contain one or more double bonds
What are vitamins?
organic molecules with diverse funcitons that are required in the diet in very small amount
What are the two types of vitamins?
water soluble and fat soluble
What are minerals?
inorganic nutrients required in small amounts
What are calcium and phosphate important for?
building and maintaining bone (osteoporosis)
What is iron important for?
an important component of Cytochromes and for hemogoblin
What is Iodine important for?
making hormones that regulate metabolism
What is sodium, potassium, and chloride important for?
in the functioning of nerves and maintaining osmotic balance between cells
What is protein deficiency?
a diet that is insufficient in one or more amino acids, which is the most common form of malnutrition among humans
What is the difference between being undernourished and malnourished?
Undernourishments is the result of a diet that consistently supplies less chemical energy than the body requires. Malnourishment is the long-term absence from the diet of one or more essential nutrients.
What are the four distinct stages that food processing can be divided into?
ingestion, digestion, absorption, and elimination
What are the method of food ingestion?
Suspension feeders, substrate feeders, fluid feeders, and bulk feeders
What occurs in digestion?
food is broken down into molecules small enough for the body to absorb
What does mechanical digestion do?
physically breaks the food into smaller particles (usually by mastication) to increase surface area
What does chemical digestion do?
When assisted by enzymes, break intermolecular bonds with the addition of water in a process called enzymatic hydrolysis
What are proteins broken down into?
amino acids
What are polysaccharides and disaccharides broken down into?
monosaccharides
What are nucleic acids broken down into?
nucleotides, nucleosides, nitrogenous bases, sugars, and phosphates
What are fats such as triglycerides broken down into?
3 fatty acids and a glycerol
What happens in absorption?
the animal’s cell takes up small molecules discussed in the previous question
What does elimination do?
completes the process as undigested materials passes out of the digestive system
What is intracellular digestion?
hydrolysis of food inside of vacuoles.
What is extracellular digestion?
the breakdown of food outside the body in an extracellular cavity
What is the body plan of most animals with a simple structure?
a digestive compartment with one opening into a pouch called the gastrovasular cavity that functions in the digestion and distribution of nutrients throughout the body
What is the structure of most animals?
a digestive tube with two openingns, the mouth and the anus
What is a complete digestive tract or alimentary canal?
a digestive tube with two openings
How is the alimentary canal organized?
specialized compartments
Where does ingestion and inital steps of digestion occur?
in the mouth or oral cavity
What happens in your mouth?
mechanical digestion breaks the food into smaller pieces while your salivary glands secreate a substance called saliva through ducts in your mouth
What does amylase do?
hydrolyzes starch and glycogen in smaller polysaccharides and the disaccharide maltose
What is mucin
a slippery glycoprotein in saliva
What does mucin do?
protects the lining of the oral cavity and lubricates the food easier for swallowing
What are buffers?
an additional components of saliva which prevents tooth decay by neutralizing acid and antibacterial agensts such as lysosome that protect against microorganisms
What is the role of a tounge?
it plays a cirtical role in distinguishing which foods should be processed further. It helps shape the food into a ball called a bolus and push it back into the pharynx or throat region
What two passages does the pharynx open to?
the esophagun which leads to the stomach and the trachea which leads to the lungs
What does an epiglottis do?
When you swallow a flap of cartilage, the epiglottis prevents food from entering the trachea by covering the glottis-the vocal chords (Larynx) and the opening between them
What is the esophagus?
the muscular tube that moves the bolus down to the stomach by rhythmic waves of contradiction called peristalsis.
What must the bolus go through in order to enter the stomach?
the cardiac sphincter
What are peristalsis?
the alternating waves of muscular contractions that move food through the GI tract
What are sphincters?
ring-like muscular valves that act like drawstrings to close off and regulate the passage of materials
Where is the stomach located?
just below the diaphragm in the upper abdominal cavity
What does the stomach do?
Despite a few nutrients which are absorbed directly into the bloodstream from the stomach (alchohol and some drugs) but it primarily stores food and continues digestion
What does the stomach secrete?
digestive fluid called gastric juice and mixes this secretion with the food to form chyme.
What are the two components of gastric juice that carry out digestion?
HCl and Pepsin
What does HCl do?
disrupts the ECM that binds cells together in meat and plant material. The pH of this compound is about 2 which not only kills most bacteria but also denatures proteins increasing exposure to their peptide bonds
How is HCl secreted?
by parietal cells in the stomach lining
What is pepsin
a protease of protein-digesting enzyme, which works best in highly acidic enviroment
What is pepsin secreted by?
cheif cells in the stomach lining in the inactive form called pepsinogen which is converted to pepsin when HCl clips off a small portion of the molecule exposing the active site
How does the stomach lining protext itself against self-digesting?
secreting mucus
What are gastric ulcers?
damaged areas of the stomach lining that are most often caused by an acid-tolerant bacteria called Helicobacter pylori
How long will food stay in the stomach?
2-6 hours
How is stomach released into the small intestine?
by the pyloric sphincter muscle
What is heartburn?
when a person experiences gastric reflux due to the backflow of chyme into the esophagus
Where does most enzymatic hydrolysis of macromolecules occur?
in the small intestine
What happens in the first 25 cm of the small intestine, or the duodenum?
where chyme mixes with digestive juices from the pancreas, liver, and gall bladder as well as with glands from the intestinal wall
What does the pancreas do?
aids in chemical digestion by producing an alkaline solution rich in bicarbonate as well as several enzymes such as trypsin and chymotrypsin which are proteases secreted into the duodenum in inactive form
What does lipase do?
enzymaticaly breaks down lipase
What secretes lipase?
the pancreas
What do nucleases break down?
nucleotides
What releases nuclease?
the pancreas
Explain the digestion of fats and other lipids in the duodenum?
relies on production of bile which is made in the liver and stored in the gall bladder
Is bile an enzyme?
no
What does bile do?
emulsifies fats into smaller droplets with greater surface area which then can go through enzymatic hydrolysis by lipase secreted by the pancreas
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Salivary amylase
Salivary glands; mouth; starch, glycogen; maltose, polysaccharides; no
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Pancreatic amylase
Pancreas; small intestine; polysaccharides; dissaccharides; no
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Disaccharidases
Small intestine; small intestine; dissaccharides; monosaccharides; yes
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Pepsin
Stomach; stomach; proteins; smaller polypeptides; no
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Trypsin
Pancreas; small intestine; polypeptides; smaller polypeptide; no
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Chymotrypsin
Pancreas; small intestine; polypeptides; smaller polypeptides; no
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Carboxypeptidase
Pancreas; small intestine; small polypeptides; amino acids; yes
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Aminopeptidases
Intestinal epithelium, small intestine, protein fragments, amino acids; yes
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Dipeptidases
Small intestine, small intestine, protein fragments, amino acids, yes
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Lipase
Pancreas; small intestine; fat droplets; 3 fatty acids, glycerol; yes
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Nucleases
Pancreas; small intestine; DNA, RNA; nucleotides
For the following enzyme, explain its source, where it is active, its substrate, its products, and whether products are small enough to be absorbed in the small intestine: Intestinal nucleases
Small intestine, small intestine, nucleotides; nitrogen bases, 5-carbon sugar, phosphate group
What is the difference between carboxypeptidase and amino peptidase?
carboxypeptidase splits 1 amino acid at a time starting at the free carboxyl group, aminopeptidase splits one amino acid at a time starting at the free amino group
Where is most digestion completed?
duodenum
What occurs in the jejunum and ileum?
the absorption of nutrients and water
What are villi and microvilli?
projections that increase the surface area in the small intestine to increase the amount of absorption that can occur
Are most glucose, amino acids, and vitamins taken into the villia actively or passively?
actively, which allows for greater transport
What happens once a nutrient is taken into the villi?
they are taken into the blood capillaries which flow into the large blood vessel called the hepatic portal vein leading to the liver where they are processed
What are chylomicrons?
fat, cholesterol, and protein complexes that enter the lacteal inside of the villi and are carried by lymphatic systems away from the digestive tract
What is included in the large intestine?
colon, cenum, and rectum
What is the colon responsible for?
the absorption of water by osmosis
What is the cecum?
a pouch taht is important in fermenting ingested material, especially in herbivores.
What is the appendix?
a finger like extension of the human cneum that has a minor and dispensable role in immunity
What are the foru basic types of teeth?
incisors, canines, premolars, and molars
What do incisiors do?
kill prey, rip and cut flesh
What do canines do?
kill prey, rip and cut out flesh
What do premolars do?
crush and shred food
What do molars do?
crush and shred food
What is the form of an animal’s digestive system directly related to?
its diet
Wgat does the collection of bacteria (the microbiome) do?
1.) Produce vitamins
2.) Regulate development of intestinal epithelium
3.) Help with the function of the innate immune system
4.) Aid in the absorption of water in the large intestine
What do many herbivores house?
mutualistic protists or bacteria which digest cellulose for them as they are unable to digest it on their own
What are ruminants?
organisms that have four stomach chambers and depend on microorganisms to aid in digesition
What is enteric division?
the branch of the nervous system that helps to regualte the activities of the digestive organisms
What is gastrin?
an hormone that is secreted by the stomach and circulates via the bloodstream back to the stomach where it stimulates production of gastric juices by positive deedback
What is secretin?
a hormone secreted by the duodenum and stimulates the release of sodium bicarbonate from the pancreas, which neutralizes chyme
Explain the role of CCK
Amino acids or fatty acids trigger the release of cholecystokinin (CCK) from the duodenum which stimulates the relases of enzymes from the pancrease and of bile from the gall bladder
Explain negative hormonal feedback in the digestive system?
When chyme rich in fats enter the duodenum, secretin and CCK inhibit peristalsis by the stomach, therby slowing figesition
What is the first site used in energy storage in humans?
the liver and muscle cells, whcih is stored in glycogen
How are excess calories taken in?
stored first in the form of glycogen and then secondarily in the form of fats i adipose tissue
What is the order in which animals burn nutrients?
Lipids, carbohydrates, and then proteins
Explain digestion in the following organ, if there is any: Mouth
Both chemical and mechanical digestion; salivary amylase breaks down starch and glycogen
Explain digestion in the following organ, if there is any: Salivary glands
Chemical digestion, salivary amylase
Explain digestion in the following organ, if there is any: Esophagus
No digestion occurs in the esophagus
Explain digestion in the following organ, if there is any: Stomach
Chemical and some mechanical: pepsinogen (pepsin) and HCL break down polypeptide chains
Explain digestion in the following organ, if there is any: Small Intestine
Chemical and Mechanical (emulsification): Enxymes from pancreas, liver, disaccharidases, dipeptdiases, nucleotidases, and nucleosidases
Explain digestion in the following organ, if there is any: Pancreas
No digestion, but produces pancreatic amylase, pancreatic peptidases, pancreatic lipase, and sodium bicarbonate
Explain digestion in the following organ, if there is any: Liver
No digestion, but produces bile
Explain digestion in the following organ, if there is any: Gall bladder
Stores bile
Explain digestion in the following organ, if there is any: Ilium
absorption
Explain digestion in the following organ, if there is any:Jujenum
Continues work of duddenum
Explain digestion in the following organ, if there is any: Large intestine
reabsorption of water
Explain digestion in the following organ, if there is any: Rectum
Holds solid waste
