Nutrient Procurement Flashcards
refers to any substance required for the growth and maintenance of an organism
nutrition
produce their own food
autotrophs
sunlight or chlorophyll-bearing
phototrophs
chemical or inorganic chemical reaction
chemotrophs
cannot produce their own food
heterotrophs
food are reduced to more simple molecular forms
digestion
Feeding Mechanism: Feeding in Particulate Matter
- Suspension feeding
- Filter feeding
- Deposit feeding
- Fluid feeding
- Bulk feeding
ciliates surface to produce currents that draw drifting food particles in their mouth
suspension feeding
possess filtering devices that strain food from water as it passes through
Filter feeding
part or an organ which resembles the barb of a feather, particularly the side branches on the stalks of crinoids
pinnules
exploits deposit of disintegrated organic material that accumulates on and in substratum
deposit feeding
process of obtaining nutrient by consuming fluids of other living organisms
fluid feeding
obtaining nutrients by eating all of the organism
bulk feeding
What do some invertebrates that doesn’t have teeth use to bite or hold
- beaks
- toothlike structures
4 types of teeth of Mammals
- incisors
- canines
- premolars
- molars
biting, cutting, stripping
incisors
seizing, piercing, tearing
canines
grinding and crushing
premolars and molars
Modified tooth
- elephant’s tusk
- modified canines
scrapping mouth part that looks like a tongue
radula
(insects) for grinding and cutting
mandibles
(horses and cows) for grinding
corrugated molars
Two types of parasites
- Endoparasites
- Ectoparasites
mechanically and chemically break food into small units for absorption
digestion
breakdown of food happens inside the cell
intracellular digestion
breakdown of food happens outside of the cell
extracellular digestion
Cells lining the __ or an ___ ___ specialize in forming various digestive secretions
lumen (cavity)
alimentary canal
Reduction of food to absorbable units relies on chemical breakdown by ___
enzymes
digestive enzymes are ___ or ___
- hydrolytic
- hydrolases
breaking of a chemical bond by adding water across it
hydrolysis
Food is moved through digestive tracts by ___ or ___
- cilia
- musculature
Movement is usually by ___ in acoelomate and pseudocoelomate that lack the mesodermally derived gut musculature of true coelomates
cilia
smooth muscle fibers run parallel with the length of the gut
longitudinal layer
muscle fibers embrace the circumference of the gut
circular layer
alternate constriction of rings of smooth muscle of the intestine that divides and squeeze contents back and forth
segmentation
shows how food is propelled forward by a traveling wave of contraction behind the food mass (bolus)
peristalsis
food mass from the mouth
bolus
Five major regions of the alimentary canal
- Receiving Region
- Conduction and storage region
- Grinding and early digestion
- Terminal digestion and absorption
- Water absorption and concentration of solids
Receiving region
- Mouthparts
- Buccal cavity
- Muscular pharynx
- Salivary glands
Mouthparts
- mandible
- jaws
- teeth
- radula
- bills
mouth
buccal cavity
throat
muscular pharynx
salivary glands
buccal glands
produce lubricating secretion that contains mucus
salivary glands
carbohydrate-splitting enzymes that begins hydrolysis of plants and animal starches
salivary amylase
Salivary amylase doesn’t completely hydrolyze starch but breaks it mostly into ___
maltose (glucose+glucose)
- assist food manipulation and swallowing
- used as chemosensors
tongue
- determine palatability of food
- food capture
- olfactory sensor
tastebuds
tips down over the trachea as food slides into the pharynx
epiglottis
prevents food particles from going further
contraction of laryngeal muscles
Once food is in the esophagus, ___ ___ of ___ ___ forces it smoothly toward the stomach
peristaltic contraction
esophageal muscles
chewing
mastication
swallowing
deglutition
happens when a mixture of gastric juices, and sometimes undigested food, rises back up the esophagus and into the mouth
regurgitation
transport food to the digestive region
esophagus
esophagus expanded into ___, used for food storage before digestion
crop
Reception
- mouthparts
- salivary glands
Conduction
esophagus
storage and early digestion
- stomach (vertebrates)
- crop (insects, birds)
Grinding
- gizzard (birds)
- proventriculus (insects)
Terminal Digestion and Absorption
- small intestine (vertebrates)
- midgut (insects)
Water Absorption, Concentration of Solids
- large intestine (vertebrates)
- hindgut (insects)
- provides initial digestion
- storage and mixing food with digestive juices
stomach
assisted by stones and grit swallowing along with food by hardened linings
muscular gizzards
- Blind tubules or pouches arising from the main passage supplements stomachs of invertebrates.
- Lined with epithelium and cells specialized for secretion of mucus or digestive enzymes, or absorption/ storage.
digestive diverticula
digests cellulose
cellulase
what microorganisms can produce cellulase
- bacteria
- protozoa
opens reflexively to allow food to enter, then closes to prevent regurgitation back into the esophagus
cardiac sphincter
In humans, ___ ___ pass over the filled stomach at a rate of approx. __ each minute
- peristaltic wave
- 3 each minute
vigorous mixing
churning
- first region of the small intestine
- where food is steadily released
duodenum
regulates flow of food into the intestine and prevents regurgitation into the stomach
pyloric sphincter
what do deep tubular glands in the stomach secrete?
gastric juice
Three (3) types of cells that line the tubular glands in the stomach
- goblet cells
- chief cells
- parietal or oxyntic cells
secrete mucus
goblet cells
secrete pepsinogen
chief cells
secrete hydrochloric acid
parietal or oxyntic cells
precursor of pepsin
pepsinogen
a ___ produced from pepsinogen only in an acid medium
protease
protease
protein-splitting enzyme
main protease in the stomach
pepsin
not digested by its own powerful acid secretions results from another gastric secretion
stomach mucosa
highly viscous organic compound
mucin
bacteria that secretes toxins causing inflammation of the stomach’s lining
Helicobacter pylori
milk curdling
rennin (found in cows)
what activates the pepsinogen
hydrochloric acid
partly digested food returned from the first stomach of ruminants to the mouth for further chewing
cud
an animal (such as a cow or sheep) that has more than one stomach and that swallows food and then brings it back up again to continue chewing it.
ruminant
- 1st chamber
- acts as a storage or holding vat for feed
- fermentation vat
- grows microbes that digest or ferment feed and make volatile fatty acids
rumen
- 2nd chamber
- pouch-like structure
- heavy or dense feed and metal objects eaten drop into this compartment
reticulum
- globe-shaped structure
- absorbs water and other substances from digestive contents
omasum
- only compartment lined with glands
- release hydrochloric acid and digestive enzymes, needed to breakdown feed
- similar to nonruminant stomach
abomasum
food mass from stomach
chyme
pathway for conducting wastes from the body
intestine
equipped with simple stomachs
invertebrates intestine
equipped for digestion and absorption
vertebrates intestine
length of intestine may exceed eight times the length of their body
coiling
Two secretions poured in the duodenum
- Pancreatic juice
- Bile
- neutralizes gastric acid
- raise pH of chyme
- intestinal enzymes are effective only in a neutral or slightly alkaline medium
pancreatic juice
liver secretes bile into the __ __
bile duct
- a fluid that is made and released by the liver and stored in the gallbladder
- breaks down fats into fatty acids, which can be taken into the body by the digestive tract
bile
an expansible storage sac that releases bile when stimulated by the presence of fatty food in the duodenum
gallbladder
reduce surface tension of fat globules, allowing the churning action of the intestine to break fats into tiny droplets
bile salts
bile salts are mainly
- sodium taurocholate
- sodium glycocholate
churning action of the intestine to break fats into tiny droplets
emulsification
breakdown products of hemoglobin from aged red blood cells
biliverdin and bilirubin
pancreatic secretion of vertebrates
pancreatic juice
enzymes in the pancreatic juice
- trypsin
- chymotrypsin
removes amino acids from carboxyl ends of polypeptides
carboxypeptidase
hydrolyzes fats into fatty acids and glycerol
pancreatic lipase
starch-splitting enzyme identical to salivary amylase in its action
pancreatic amylase
degrade RNA and DNA to nucleotides
nuclease
middle part of the small intestine
jejunum
last part of the small intestine
ileum
large intestine
colon
A pouch that forms the first part of the large intestine.
cecum
start of the colon
ascending colon
lies across the upper part of the abdomen
transverse colon
follows the transverse colon and splenic flexure. It is on the left side of the abdomen
descending colon
last part of the colon and connects to the rectum
sigmoid colon
where nutrients is absorbed
small intestine
provide enormous surface area in the small intestine
- finger-shaped villi
- microvilli
Carbohydrates are absorbed as ___ ___ because the intestine is virtually impermeable to polysaccharides
simple sugars
Proteins absorbed as their ___ ___ subunits, although limited amount may be absorbed
amino acid
Passive transfer is supplemented by an ___ ___ ___ located in epithelial cells that transfers digested food molecules into the blood
active transport mechanism
where reabsorption of water happens
large intestine
removal of wastes from the body
defecation
specialized ___ ___ absorb water and ions as needed, leaving behind fecal pellets that are almost completely dry
rectal glands
___ ___ located in the hypothalamus and brainstem of the brain regulate the intake of food
hunger centers
nutrients from blood to the receiving cells
assimilation
nutrients from lumen to bloodstream
absorption
In brown fat, ___ is generated instead of ___
heat
ATP
hormone produced by fat cells was found to cure obesity in mutant mice
leptin
- small polypeptide hormone produced by endocrine cells in the pyloric portion of the stomach
- response to stimulation by parasympathetic nerve endings when protein food enters the stomach
gastrin
- polypeptide hormone and has a striking structural resemblance to gastrin
- response to presence of fatty acids
cholecystokinin (CKK)
- produced by endocrine cells in the duodenal wall
- response to food and strong acid in the stomach and small intestine
secretin
fatty substances are deposited in the lining of arteries
atherosclerosis
___ ___ rise before a meal to increase appetite
Ghrelin levels
Two types of vitamins
- fat soluble
- water soluble
- low calories
- low protein
Marasmus
- adequate calories
- low protein
Kwashiorkor
