Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Digestion in animals
Nutrition, digestion, human digestive system, digestive adaptations
| Question | Answer |
|---|---|
| Define animal nutrition | Process by which food is taken in, taken apart & taken up in animals |
| 3 categories of nutrition | Herbivores (eat mainly plants & algae), carnivores (eat other animals/meat), omnivores (regularly consume meat as well as plants/algae). Most animals r opportunistic feeders |
| An animal’s diet must supply | Chemical energy (converted into ATP to power cellular processes), organic building blocks (to synthesize a variety of molecules) & essential nutrients |
| Stages of food processing | Digestion, absorption, elimination |
| Mammalian digestive system | Formed by organs specialized for the sequential stages of food processing. Adaptations of this system correlate with diet |
| Dietarry macromolecules (define + types) | Ingested, digested, assimilated & used as organic molecules for growth, maintenance & reproduction. Carbohydrates (sugars), proteins, nucleic acids, lipids (fats) |
| Essential nutrients (define + types) | Materials that an animal cannot assemble from simpler organic molecules - must be obtained from the diet. Essential amino acids, essential fatty acids, vitamins, minerals |
| Essential amino acids | Animals need ~20 amino acids & can make half, need rest from diet in preassembled form. Most plant proteins r incomplete in amino acid composition - herbivores need to eat specific plant mixes. Some animals who need lots of proteins have adaptations |
| Essential fatty acids | Animals can synthesize most of the fatty acids needed, others r needed from diet & include certain unsaturated fatty acids. Fatty acid deficiency is rare |
| Vitamins & the 2 types | Organic molecules required in the diet in very small amounts. 13 vitamins are essential for humans, vitamins grouped into 2 categories: fat-soluble (A, D, E, K) & water-soluble (B series, C) |
| Minerals | Simple inorganic nutrients, usually required in small amounts. Sodium, chloride, potassium, iron, iodine, magnesium, calcium, phosphorous & sulfur |
| vitamin B1 - function & symptoms of deficiency | (thiamine) - coenzyme for removing CO2 from compounds, deficiency: beriberi (tingling, poor coordination, reduced heart function) |
| vitamin B3 - function & symptoms of deficiency | (folic acid) - coenzyme in nucleic acid & amino acid metabolism. deficiency: anemia, birth defects |
| 4 parts of animal nutrition | Ingestion, digestion, absorption, elimination |
| Digestion & types | Process of breaking down food into small molecule that can be absorbed. Intercellular & extracellular digestion, mechanical & chemical digestion |
| Malnutrition vs under nutrition | Malnutrition refers to any diet-caused condition due to failure in uptake of essential nutrients (deficiency, excess or imbalance). Undernutrition - type of malnutrition where there is deficiency of specific essential nutrient |
| Possible consequences of deficiencies in essential nutrients in animals | Varied, depends which nutrient is missing, severe widespread effects such as: nervous system dysfunction, muscle weakness/decay, bone irregularities or decay, heart dysfunction, skin problems, gastrointestinal problems, anemia/blood clotting problems etc. |
| Mechanical & chemical digestion | Mechanical: breaking down food into smaller particles, uses muscle tissue is essential in walls of gastrovascular cavity, chemical: use of enzymes + chemical processes to break apart food particles, secretion of enzymes by walls of gastrovascular cavity |
| Intracellular digestion | Digestion at cellular level - enzymes digesting individual molecules, ingest of phagocytosis then use food vacuole. Only chemical digestion. Amoeba & sponges |
| ADV & DAV of intracellular digestion | ADV: very quick receiving nutrients directly to the cells, DAV: limits the size & amount of food & becomes inefficient at higher structural complexity |
| Extracellular digestion | Food is digested externally to the organism’s cells, stays in gastrovascular cavity. Steps: ingestion, digestion, absorption, elimination |
| ADV & DAV of extracellular digestion | ADV: can eat things almost as big as organism (more energy per nutritional event) + food is contained, DAV: digestion takes much longer + need external enzymes + food needs to be transported to the cells |
| Examples of organisms that use intracellular and/or extracellular digestion | Intracellular only - porifera, amoeba. Extracellular & Intracellular - platyhelminthes, Cnidaria. Extracellular only - most animals: annelids, arthropods, reptiles, mammals, etc. |
| ADV & DAV gastrovascular cavity | ADV: distribution (used to transport nutrients around body & to cells), doesn’t require another transportation system. DAV: all processes in one cavity, one piece of food at a time |
| ADV & DAV of alimentary canal | ADV: can keep eating - food moves thru one way, specialization - different parts do dif. functions along one-way system = more efficient, DAV: requires more energy, another transportation system to get nutrients to cells |
| how does an amoeba eat a bacterium? | uses its pseudopods to reach out and wrap around a bacterium, enveloping it in its cytoplasm, forming a food vacuole around it and breaking it down into nutrients with hydrolytic enzymes and absorbing them directly into the cytoplasm |
| how does a hydra digest inter- and extracellularly? | hydra ingests food into a gastrovascular cavity w enzymes, digests extracellular, then gastrovascular cavity is used as transportation, stretching to all areas of the hydra's body, and allowing intercellular digestion in its cells |
| describe food's pathway thru the earthworm digestive system & function of each part | food ingested by mouth, transported by pharynx & esophagus, stored in crop; when needed, food churned in gizzard & digested, smaller food particles passes into intestine where it's absorbed; leftover waste eliminated thru anus |
| describe an earthworm's digestive tract | has a mouth, pharynx, esophagus, crop, gizzard, stomach, intestine & anus. Long, tubular thin tract w pharynx, crop & gizzard taking up central space, fairly straight from mouth to anus |
| describe a grasshopper's digestive tract | has a mouth, esophagus, crop, stomach w gastric cecae, intestine, rectum & anus. Shorter, wider digestive tract, fairly straight from mouth to anus. Larger, wide stomach & rounded intestine |
| describe a bird's digestive tract | mouth, esophagus, crop, stomach, gizzard, intestine & anus. Alimentary canal meanders thru crop, stomach & gizzard, each spherical & sac-like. Intestine twists, turns & folds on itself more like human intestine then connects to anus |
| what adaptation increases absorptive surface of intestine in sharks? | spiral valve. it slows down the passage of food so more nutrients can be absorbed in the small intestine |
| how is food moved along the alimentary canal and how is food passage regulated between compartments? | peristalsis moves food along, sphincters regulate passage |
| what are the structures of the human digestive system (generally anterior to posterior)? | oral cavity, tongue, salivary glands, pharynx, esophagus, liver, (esophageal sphincter), stomach, pyloric sphincter, gallbladder, duodenum, pancreas, small intestine, large intestine, rectum, anus |
| functions of: oral cavity, teeth, tongue, salivary glands | oral cavity - ingestion & digestion of food; teeth - mechanical digestion; tongue - detecting food, moistening food, swallowing; salivary glands - secretion of saliva (salivary amylase) |
| what is salivary amylase? | a hydrolytic enzyme in the saliva, produced by salivary glands. Begins the chemical digestion of starch in the oral cavity |
| functions of: pharynx, esophagus | pharynx - regulates swallowing & passage of food or air; esophagus - transporting bolus (chewed food) to the stomach via peristalsis |
| what is peristalsis? | the alternate contraction of circular & longitudinal smooth muscles, typically to move material along internal passageways |
| describe function(s) of stomach & link it to its structure | mechanical digestion - 3 muscle layers to churn bolus into acid chyme; chemical digestion by HCl & pepsin - gastrointestinal glands; food storage - folds (rugae) so it can stretch to hold lots of food; protecting body (next card) |
| how does the stomach act as a security checkpoint for the digestive system/body? | acidic gastric juice kills pathogens & 2 sphincters: esophageal sphincter is loose, allowing for regurgitation of toxic substances, while pyloric sphincter is a tight close that regulates how fast food moves thru digestive tract & protects rest of tract |
| how does the stomach mechanically & chemically digest food? | mechanical - 3 muscle layers churn & mix food, breaking it up w help of HCl in gastric juice; pepsin is activated during digestion (inactive - pepsinogen), beginning the chemical digestion of protein; some lipase present to start breaking down fats |
| functions of: liver, gallbladder, pancreas for digestion | liver - produces bile; gallbladder - storage & release of bile; pancreas - produces pancreatic juice which has the majority of enzymes needed to complete chemical digestion |
| what is the duodenum? | the tube between the stomach and the small intestine, where the majority of chemical digestion is completed w help of bile salts & pancreatic juices |
| function(s) of small intestine linked to its structure | main site of absorption of nutrients. It is long, convoluted, & has many folds lined with villi to maximize surface area |
| what are villi & microvilli? | villi - finger-like projections across surface of small intestine with specialized absorptive cells & connections to blood & lymph vessels; microvilli - brush border lining the villi |
| why is surface area important for absorption? | maximize surface area = as many nutrients as possible in contact with cells at any given time & transported into cytoplasm |
| functions of: large intestine, rectum, anus | large intestine - absorption of water & salts, production of feces; rectum - stores feces; anus - sphincter that regulates defecation |
| what is bile? | bile salts emulsify lipids (break them into smaller droplets). They are not enzymes, they are like soap |
| compare small & large intestine based on: length, width, location | small is longer; large is wider; small located centrally to abdomen, connects to stomach & large intestine, which surrounds it & connects to rectum |
| where in human digestive system are carbohydrates, proteins, nucleic acids & fats digested? | carbs - oral cavity, duodenum; proteins - stomach, duodenum; nucleic acids - duodenum; fats - duodenum |
| role of salivary amylase, where it functions, its substrate & products | begins chemical digestion of starch in oral cavity, digests polysaccharides into smaller pieces |
| role of pancreatic amylase, where it functions, its substrate & products | completes chemical digestion of carbs in duodenum, digests polysaccharides into disaccharides |
| role of pepsin, where it functions, its substrate & products | begins chemical digestion of protein in stomach, digests proteins into polypeptides |
| role of trypsin, where it functions, its substrate & products | chemical digestion of protein in duodenum, digests small polypeptides into smaller polypeptides |
| role of lipase, where it functions, its substrate & products | chemical digestion of fats in duodenum, digests fats into glycerol, fatty acids & monoglycerides |
| role of pancreatic nuclease, where it functions, its substrate & products | begins chemical digestion of DNA/RNA in duodenum, digests DNA/RNA into nucleotides |
| why can a person live without a gallbladder, but not without a liver or pancreas | bc gallbladder only controls storage & release of bile. Liver produces bile so it could be rerouted to duodenum if gallbladder is removed. Pancreas produces majority of enzymes for chemical digestion |
| describe hormonal control of digestion in humans | hormones r released in response to stomach & environment. presence of proteins = gastrin secreted by stomach, stimulating release of HCl. Stomach emptied = somatostatin stops release of HCl. Hormones also tell pancreas/gallbladder when to release |
| describe shape & presence of incisors, canines, premolars & molars for carnivores. How does this suit their diet? | sharp incisors, large & sharp canines, pointy premolars & molars. Great for puncturing, killing & gripping prey, tearing & chewing meat |
| describe shape & presence of incisors, canines, premolars & molars for herbivores. How does this suit their diet? | flat, sometimes enlarged incisors, reduced or absent canines, flat & wide, ridged premolars & molars. Great for chewing & grinding plant-like material |
| describe shape & presence of incisors, canines, premolars & molars for omnivores. How does this suit their diet? | blade-like incisors, may have large or reduced canines, tend to have flattened premolars & molars w cusps. Flexible, allowing omnivores to kill & injure prey, chew meat & plant-like material |
| why do carnivores have large stomach, shorter small intestine & smaller cecum than herbivores? | stomachs large to expand & hold lots of prey over long periods of time & digest lots of protein; shorter small intestine bc nutrients r absorbed quicker than herbivores (plants are tough); smaller cecum bc they don't need as many digestive microorganisms |
| why does presence of lots of cellulose require special adaptations for herbivores? how do they digest cellulose? | animals cannot produce the enzyme to digest cellulose by themselves; it is very tough material. Have to recruit help of mutualistic microorganisms living in their gut |
| what is purpose of large cecum in herbivores? | to harbour lots of cellulose-digesting microorganisms |
| what is the typhlosole in earthworms? | a precursor to folds found in the small intestine of earthworms. it increases surface area & the # of cells exposed to food in the alimentary canal |
| what are ruminants? | organisms with a 4-chambered stomach & large specialized chamber (rumen) where mutualistic microorganisms digest cellulose. Some (ex. cows) circulate foodstuffs to be further broken down |
| what is cellulose broken down into? | mostly sucrose, some other proteins & lipids |
| what is coprophagy? | ingestion of feces for further digestion/absorption |
| where in rabbits & ruminants is cellulose digested? | rabbits - cecum;; ruminants - in fermentation chambers (rumen) |
| describe coprophagy in rabbits | rabbits produce 2 types of feces: soft pellets - ingested to absorb nutrients from cellulose digestion that were made available but not absorbed, & hard pellets - waste that is eliminated |
| how does the site of cellulose digestion influence rabbits' feeding behaviour, digestive tract structure & nutrient absorption | cellulose can only be digested in cecum near end of digestive tract = not all nutrients can be absorbed from cellulose before it exits body -> coprophagy. smaller digestive tract, large cecum |
| how does the site of cellulose digestion influence ruminants' feeding behaviour, digestive tract structure & nutrient absorption | cellulose is digested in large gastrointestinal chambers. Food cycles thru digestive tract multiple times to allow completion of digesting cellulose & full absorption of nutrients. Large, 4-chambered system |
| vitamin B12 - function & symptoms of deficiency | (cobalamin) - production of nucleic acids & red blood cells. deficiency: anemia, numbness, loss of balance |
| vitamin C - function & symptoms of deficiency | (ascorbic acid) - collagen synthesis, antioxidant. deficiency: scurvy (degeneration of skin & teeth), delayed wound healing |
| vitamins required in humans | B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6 (pyridoxine), B7 (biotin), B9 (folic acid), B12 (cobalamin), C (ascorbic acid), A (retinol), D, E (tocopherol), K (phylloquinone) |
| minerals required in humans | calcium, phosphorous, sulfur, potassium, chlorine, sodium, magnesium, iron, fluorine, iodine |
Created by:
AntBanana
Popular Biology sets