Animal Nutrition Flashcards
What are the three categories of animal diet?
Herbivore - feed on plants or algae
Carnivores - eat other animals
Omnivores - eat other animals as well as plants or algae
How does the book define nutrition?
food being taken in, taken apart, and taken up.
What are the three things that an animals diet should supply?
Chemical energy - to be used in cellular processes like ATP productionor gene expression
Organic carbon (sugars) and nitrogen (proteins) to build macromolecules (proteins, fats, sugars, nucleic acids)
Essential nutrients - materials that animal cells require but cant be synthesized by the animal
What are some roles of essential nutrients?
Enzyme substrates (linoleic acid)
Coenzyme
Cofactors (minerals)
Essential amino acids
How many different amino acids do animals use? How many of these are essential, and what does that mean?
Animals use 20 different amino acids
8 of these are essential meaning that they must be obtained in a prefabricated form
What is the difference between plant and animal proteins?
plant proteins are incomplete which means they dont provide all of the essential amino acids that animals need.
animal proteins are complete (meat and eggs) which means they provide all essential amino acids animals need
What is a primary use of fatty acids? Does a deficiency in this often occur?
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to make the cell membrane
Deficiency does not often occur
How many vitamins are there total? What are they divided into? How can you remember them?
13
Water soluble - B vitamins and C
Fat soluble - A, D, E, K
What is the condition called when deficient in vitamin C? B9 and B12? D?
C - scurvy
B9 & B12 - anemia
D - Rickets (bone deformities in children, soft bone in adults)
What is the typical function of vitamins? Are they generally needed in large amounts?
Usually coenzymes, needed for an enzyme to carry out its function
Needed in typically small amounts
Are minerals organic or inorganic? What are they used for?
Inorganic
Needed for enzymes and nerves to function
What are some examples of minerals we need?
Less than 200mg/day - Fe. Fluorine, Iodine
More than 200mg/day - Mg, Ca, Na, Cl, K, P, S
What is iodine used for?
Thyroid hormone
Deficiency in calcium and phosphorus?
Bone loss
Deficiency in iodine causes?
goiter, weakness
Too much sodium may cause?
HTN
What does malnutrition mean? How does it differ from undernutrition?
Malnutrition - failure to obtain adequate nutrition
Undernutrition - not enough food to provide adequate chemical energy for body.
What is golden rice?
an engineered rice strain that contains beta-carotene that is converted to vitamin A by the body.
Can deficiencies in essential nutrients cause deformities, disease, or death?
YES
What are some things that will happen to an undernourished individual?
- use up stored fat and carbohydrates
- break down its own proteins
- lose muscle mass
- suffer protein deficiency in the brain
- die or suffer irreversible damage
How might cattle, deer, and other herbivores prevent deficiencies in phosphorus?
Consuming concentrated sources of salts and other minerals.
What are the four main stages of food processing in animals and their basic description?
- Ingestion - act of eating or feeding
- Digestion:
- Mechanical - act of chewing to break down food to smaller pieces to create more surface area for enzymes to act.
- Chemical via enzymatic hydrolysis to break down to monomeric units - Absorption - molecules absorbed by bodies cells
- Elimination - undigested foods passed out of body
What are the four ways animals feed and some examples of each?
Filter or suspension feeding - sifting small food particles from the water. Mostly aqautic animals that do this, like humpback whale.
Substrate feeding - animals that live in on on their food source. Maggots or leaf miner caterpillar.
Fluid feeding - suck nutrient-rich fluid from living host. Like mosquitos, bees, hummingbirds.
Bulk feeding - eat relatively large pieces of food. Such as humans, pythons.
What are the two types of digestion covered in class and descriptions of each?
Intracellular digestion - occurs inside the cell in food vacuoles that contain hydrolytic enzymes (contained in lysosomes that attach to vacuole). ALL ANIMALS PERFORM THIS. SEE PIC.
Extracellular digestion - occurs outside the cell in body compartments.
What are the two types of compartments where extracellular digestion occurs that an animal may have? Advantages or disadvantages?
- Gastrovascular cavity - Have a single opening (mouth/anus) to a digestive pouch that also distrubutes nutrients throughout the body (vascular). Cnidarians (jellyfish, polyps, corals) sponges, and flatworms.
- Alimentary canal - Complete digestive tract (mouth and anus). earthworms, insects, birds, and humans.
The advantage of an alimentary canal is that one compartment can be used for ingestion while another can digest.
P.902 for pictures of each of these.
What are the different organs vs. the different accessory glands in the mammalian digestive tract? What is a sphincter?
Organs - esophagus, stomach, small and large intestine, rectum
Accessory glands - salivary glands, pancreas, liver, gallbladder
A sphincter is a bottleneck between major compartments.
Why do we need a sphincter between esophagus and stomach? Stomach and small intestine?
Stomach and esophagus - prevents reflux of acid, limits amount of food we can eat.
Stomach and small intestine - allows for stomach to begin digestive processes before food moves into smal intestine.
What is the function of the pancreas, liver, and gallblader in the digestive system? Does the stomach absorb anyhting? Basic function of small intestine and large intestine
Pancrease - releases digestive enzymes into the small intestine.
Liver - produces bile to emulsify fats in small intestine.
Gallbladder - stores bile produced by liver.
Stomach aids in digestion ONLY
Small intestine - further digestion AND absorption
Large intestine - resorption of water and form feces
Describe the purpose of thses components: oral cavity, salivary glands (4 parts of saliva), teeth, tongue, pharynx, and esophagus.
- Oral cavity - Ingestion
- teeth - grind food (mechanical digestion)
- tongue - shapes food into bolus or ball - Salivary glands - secrete saliva that is composed of:
- Mucous - protect mouth, lubricate food
- amylase - hydrolyzes starch and glycogen to small polysaccharides (chemical digestion)
- Lysozyme - kills bacteria
- buffers - neutralize acidity and prevent tooth decay - Pharynx (throat) - branches into trachea and esophagus
- epiglottis - covers trachea when swallowing - Esophagus - has muscles that push bolus down the stomach via:
- Peristalsis - alternating waves of smooth muscle contraction and relaxation
When trachea is open (epiglottis up and not down), even while chewing, the esophageal sphincter is?
closed (contracted) to allow for breathing even while chewing.
LOOK AT PICTURE
Why does the stomach have many folds and elastic walls?
So it can expand
Where is gastric juice secreted and what does it consist of?
HCl (hydrochloric acid) and pepsin (protease - enzyme that breaks down proteins)
Become familiar with this picture.
In the jejunum and ileum, these regions are highly folded into what are called? Each epithelial cell of these regions have many microprojections called what?
What is the purpose of these two structures?
Folds are called villi
Each epithelial cell have microprojections called microvilli
The purpose of these villi and microvilli is to increase the surface area for nutrient absorption
Describe triglyceride absorption in 5 steps.
- Large fat globules in small intstine are broken into fat droplets via bile salts.
- Lipase breaks down triglycerides in fat droplets into fatty acids and monoglycerides
- fatty acids and monoglycerides diffuse into epithelial cell and reform into triglycerides (some glycerols and fatty acids pass directly into capillaries)
- triglycerides are incorporated into chylomicrons which make them water-soluble
- These chylomicrons leave epithelial cell via exocytosis and enter lacteals (part of lymphatic system) where the lymph takes them to large veins and eventually to heart.
Describe the evolutions of dentition in regards to herbivores, carnivores, and omnivores.
Carnivore (dogs and cats) - long pointed incisiors and canines. jagged premolars and molars.
Herbivore (horses and deer) - premolars and molars with broad, ridged surfaces. Incisors and canines modified for biting off pieces of vegetation, may not have any canines in some cases.
Omnivores (humans) - adapted to both plants and meat consumption. pointed canines, blade-like incisors, premolars for grinding and molars for crushing.
Describe the stomach and intestinal adaptations between carnivors, omnivores and herbivores discussed in class.
Carnivors - large expandable stomachs to allow for long time between meals and allows for bulk eating once prey has been caught (like in python or a lion)
Herbivores and Omnivores - Have longer alimentary canals (as well as cecums) in relation to their body size than carnivores. this allows the longer required time for plant digestion to occur (cell walls make them tough). For example between the similarly sized koala and coyote the koalas intestines are much longer.
Understand blood glucose control via negative feedback loops.
BG rises - pancreas beta cells release insulin - insulin stimulates glycogen storage in liver and glucose shift into cells (especially skeletal muscle) - blood glucose levels drop back down
BG falls - pancreas alpha cells release glucagon - liver releases glucose into blood via glycogen stores - glucose level rises
