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NIU / Engineering / BIOS 209 / In what way does enzymes help animals in digestion?

In what way does enzymes help animals in digestion?

In what way does enzymes help animals in digestion?


School: Northern Illinois University
Department: Engineering
Course: Funds of Organismal Biology
Professor: Nicholas barber
Term: Fall 2015
Cost: 50
Name: Exam 3 Study Guide
Uploaded: 11/03/2015
36 Pages 195 Views 5 Unlocks

Ben Minarick (Rating: )

BIOS 209 Study Guide 3  

In what way do enzymes help animals in digestion?


General Characteristics  

-Eukaryotes -Multicellular -Heterotrophic

-Ingest food

-enzymes help digestion Kingdom Animalia  


-Diploid or 2N is MOST of life cycle  

-gametes are only in 1N or Haploid  

-cells organize by tissues, muscles (allow mobility) , and nerves (information about environment)  


Major Way To Group Animals


-this includes humans If you want to learn more check out What are the five basic themes of hate speech?

-makes up only 5% of the species


-95% of species


(“Body Plan”)/ General Layout Or Organization

How are animals generally grouped or classified?

1. Badially symmetrical adults = can be cut in four, equal pieces -no right, front, back -free-floating or attached to “sessile” aka substrate  

Friday, October 16, 2015  


example: Blue Jellyfish  

2. Bilaterally symmetrical adults = cut in half down the middle  

-left, right, front, back including dorsal, ventral; lateral  If you want to learn more check out What were the effects of the great migration?

-includes directional mobility and cephalization (head/brain)  

How does the embryo of a sea urchin develop?

-example: Cardinal has male + female chromosomes  

Embryo Development of Sea Urchin  

-zygote - 2 -4- 8  

-Gastrula stage: gut begins to form also (cell differentiation starts here)  

-Blastual: round like ball  

 1. ectoderm- skin + nerves

 2. mesoderm -muscles +skeleton+circulatory  

 3. endoderm - gut linning  

Separate Mouth and Anus  

-example: opens at other end - through body  Don't forget about the age old question of What is cardiac output?

-a derived trait, NOT found in all animals  

-meaning that it evolved after animals diverged from other eukaryotes and began to diversify  

-Ancestral trait: stop here, example: one opening (sponge + Jellyfish) -Derived trait: two  openings (not ancestors)


-occurs 1st  

-cleavage = fixed early cell types -mouth forms 1st (Deuterstomes)

-occurs 2nd  

-intermediate cleavage = early embryo cells can each form complete organism 2  Friday, October 16, 2015  

-mouth forms 2nd

-Why would ONE cell have TWO nuclei?  


(Ways Of Grouping Animals)  

-Kingdom: Animalia aka “Metazoa”  

-Clades: Metazoa, Eumetazoa  


-considered animals  


-Aquatic, mostly marine meaning ocean-dwelling) - some in freshwater -Dolphins used them to  protect their snouts

-developed on rocks in Illinois

-Structure: jello-“like” vase  

with cells in its epidermis (outer skin layer)  We also discuss several other topics like What causes a demographic change and switch to tv?

-they are suspension feeders meaning filter  

-have specialized feeding cells that beat flagellum, then they draw from water past  

-food articles are ingested, not through the mouth but by the cell membrane ENGULFING the  food for internal digestion (PHAGOCYTOSIS)

-Sponge is sexual and asexual - reproduction (sperm and eggs produced, fuse to form zygotes  

-Hermaphrodite: perform both male and female functions, not usually at the same time -they  cannot self fertilize


Cnidarians (Phylum)  

-aquatic + marine invertebrates 3  

Friday, October 16, 2015  




Sea Anemones


(Characteristics) Don't forget about the age old question of What happens when a person commits a federal crime?

-single body opening -“Mouth Anus” -together -comes in two forms:  

 1. polyp attached, tentacles mouth-anus up  

 2. medusa floats, tentacles and mouth-anus face down

-radial symmetry

-some species repercussion includes both asexual and sexual reproduction -asexual: new polyps  can form and bud off

-sexual: produce sperm and eggs that fuse to form zygotes

-body layers = tissues (epidermis)

-gastrodermis = stomach skin layer


-2 tissues layers = diploblastic includes ectoderm and endoderm but NOT mesoderm (Coral  Reef)

-corals are polyps with exoskeleton of calcium, often hard

-live and grow on old skeletons ... build up

-dinoflagellates give coral color

-only four din clear water because symbiosis with photosynthetic algae We also discuss several other topics like In what way is attractiveness related to evolutionary theory?


-includes tapeworms  


Friday, October 16, 2015  

-cysts in meat (muscle):  

unencyst in vertebrate gut where attach with hooks  

-out of host via a segment = sac of sex organs or eggs produced by segment ..... eggs

-include trematodes, which are blood dukes, causes by schistosomiasis  

-flatworms live in human gut  

-also in freshwater ponds and rivers (planarians)  

-they can regenerate well because of stem cells throughout the body, which can differentiate  -their flat so they can get oxygen and get rid of carbon dioxide through molecules own diffusion  

-simple organ for proper dilution = protonephridia -does same jobs as our kidneys (Segmented  Worms) Annelids

-includes earthworms and leeches

-also scavengers, predators, and bloodsucking ectoparasites  

-leech anticoagulant is produced commercially by inserting that gene into unicellular fungi aka  yeasts  

-separate mouth and anus

-get round by locomote:

earthworms: bristles

leeches use front and hind suckers

-segmented via dividers = septae- repaired units -this is repeated by body cavities  

-repeated by nephridia maintains proper dilution like our kidneys -repeated blood vessel rings: front one pumps ..... hearts

-repeated nerve clumps includes somewhat of a “brain” in the “head”


Friday, October 16, 2015  

Friday, October 16, 2015  


-body plan very similar

-mantle - surrounds visceral mass, secretes shell

-gastropods= snails, slugs, and sea slugs

-scrape algae with toothed tongue

-can also be negative to herbivores in agriculture






-2 shell halves

-suspension feeders: strain food from water that passes over feeding filters -if sand or other irritant get under shell, bivalve makes secretion - pearl (Cephalopods) octopus +squid

-generally, fast moving predators

-tentacles made up of modified part of foot

-well-developed, complex brain

-most intelligent invertebrates, with apparent memory + problem solving abilities  

Nematodes (Roundworms)  

-related to Arthropods  

-shed their cuticle (external coat) as they grow called molting  


-live in oceans, freshwater habitats, soil  

-inside plants and inside animals  


-they are an important part of food webs by decomposing organic material and cycling nutrients  -in agriculture, some nematodes are harmful, and some are beneficial  

-Entomopathogenic “insect disease causing” nematodes attack plant-eating insects, helping crops  -most common parasitic one in U.S. is pinworms  

 1. eggs are ingested or breathed in

 2. eggs hatch and adults develop in intestines  

 3. females exit out anus to lay eggs at night -eggs on body and bedclothes   4. nonfat, but causes irritation  

 5. most common in temperate climates (=moderate, not extremely hot or cold)  


-very diverse

-tough/hard exoskeleton made up of large chitin -restricts growth, so anthropods molt (shed) - arth = jointed  


Tuesday, October 20, 2015  

-pod = foot or appendage

-segmented appendages perform a wide variety of functions  

-different types of appendages develop from different segments controlled by homeotic genes  (where and when)

-many terrestrial arthropods breathe through branching air tubes via openings on later; abdomen,  thorax = “tracheal system”  

-many aquatic species have gills: water moves over feathery structures with large surface area,  allowing gas exchange  

(Anthropoda Includes Arachnids) -spiders have two main body parts -scorpions: venom tipped  tail -ticks  

-daddy longlegs do not have venom, 2 body parts less distinct -spiders are a medical concern to  humans in U.S. (rarely fatal)

1. black widow (female)

a. shiny black globular abdomen with red hour glass on underside b. neurotoxin form jointed  fangs  

2. Brown Recluse

a. dark fiddle on head-end top side

-arachnids have 6 pairs of segmented appendages

-4 walking legs

- 1 pair as food-manipulators + sperm transfer

- 1 pair Chelicerae: inject venom + digestive enzymes  

Phylum Arthropoda includes Crustaceans -lobsters, shrimp, crayfish, crabs -people like to eat crustaceans


Tuesday, October 20, 2015  

-“pillbug” “rolypoly” =isopod

-giant Isopod usually in deep waters of the Atlantic and Pacific Oceans Phylum Arthropoda classes are



-Insecta -largest class :  

(1) pair of antennae = feelers, sellers  

 . (3) pairs of thoracic walking legs  

 . (4) 2 pairs of wings (usually)  

 . (5) 2 compound eyes = multifaceted; little light detectors in between  

*most insect species undergo complete metamorphosis  

-larvae wormlike, with internal wing development

-egg to larva to larva to pupa to adult

-“pop-out stage”

*some insect species: incomplete metamorphosis -larvae = miniature adults, but with wing  “pads” - can’t fly -external wing development  


egg to nymph to bigger nymph to etc. to adult Insects:

-Centipedes flattened with, venom and claws -Millipedes cylindrical mostly scavengers  (Deuterostomes)



Tuesday, October 20, 2015  

-mouth second  

-indeterminate cleavage = early embryo cells can each form a complete organism  -in gastrulation, 1st opening becomes anus; secondary opening develops into mouth  Classes incude:  

-sea stars  

-sea cucumbers  

-sea urchins, sand dollars  

-sea lilies

-live at bottom of the ocean; many attached or sedentary (=don’t move much)  -Larvae have bilateral symmetry, even if adults don’t appear to  

-no cephalization  

-can regenerate body parts that are lost  

-water vascular system: use seas water instead of blood for gas exchange oxygen in and CO2 out  -starfish are predators  

“Crown-of-thorns Seastar”  

-widespread in southern pacific ocean  

-feeds on corals  

-occasionally outbreaks, removing large areas of live coral form coral reefs  

-outbreaks have been linked to fertilizer runoff which results in more food for Crown-of- thorns  larvae, and loss of natural sea star predators  


-phylum Chordata

-includes invertebrates and vertebrates (animals) -vertebrates: fish-amphibians-reptiles-birds mammals  


Tuesday, October 20, 2015  

-derived characteristics  

-some of these characteristics only present in embryo  

-traits of of chordates:  

 1. Notochord: semirigid rod along length of body in embryo   2. a. in humans, forms discs between the vertebrae  

 3. b. tissue around the rod - rod  

-dorsal, allow nerve cord (aka. “neural tube”.. back)  

-ectoderm cells along back (dorsal surface) of embryo fold upward to create a tube  -cord develops into the brain + spinal cord (central nervous system)  -Pharyngeal slits/grooves  

 a. pharynx= region of digestive tube behind mouth

 b. b. these slits/grooves develop into  

 1. filter feeding structures  

 2. gill openings in fish  

 3. in humans: remains as grooves (not slits) -develop into jaws, inner ear, tonsils  

-post-anal tail:  

usually composed of segmented muscles and skeleton -propulsion thru water or (as in humans)  reduces during development to small vertebrae at end of spine  

-these things make a chordate

Lancelet- chordate, but invertebrate

Basal, invertebrate chordate

-displays all 4 characteristics even as adult  


Tuesday, October 20, 2015

-chordate groups defined based on shared derived characters

Hagfish- lack backbone


-makes slime mucus that may help them escape predators

-some of the slime is used in cooking in parts of Korea similar to egg whites Lamprey- vertebrae  that lacks a jaw - but they have a hard backbone  

-sea lamprey

-accidentally introduced into the Great Lakes in the 1800s

-attaches to wish and feed on their blood

-reduces populations of economically valuable game fish (e.g. lake trout) -control programs have  reduced their numbers, but still present -Gnathostomes: vertebrates with jaws -modification of skeletal rods that supported pharyngeal gill slits Dunkleosteus- extinct  prehistoric animals that showed the early jaw species -vertebrates with jaws (BUT NOT LIMBS)  - mostly fish - they lack limbs Cartilaginous Fish:

-sharks and rays

Bony Fish:

-regular fish

-vertebrates with limbs are Tetrapods (four feet)

-limbs have digits (fingers and toes)

-allow movement on land: terrestrial

-transitional fossils in between fish and amphibians exist

-vertebrates with limbs (but not amniotic eggs) are amphibians

ex: frogs and salamanders  


Tuesday, October 20, 2015  

Tuesday, October 20, 2015  

-extinction rate is high

-their eggs are surrounded by gelatinous coating that is permeable to gasses + water -no sac -similar eggs

-some on land/water or completely aquatic


-reptiles, mammals, birds

-similar extra embryonic membranes

-most have shell: produced in mother

-it provides fluid environment on land

Extra embryonic membranes:

amnion- contains embryo an fluid to protect against shocks

yolk sac- contain nutrients that are transported to the embryo

allantois- waste receptacle

chorion- gas exchange

*last two forms placenta in humans and other (non-marsupial) mammals *NO monophyletic clades  

(Chordate Evolution)  

-remember that all have a shared ancestor at the end of the tree  

-remember that fish are a paraphyletic clade  

Fish Generally Have:  

A. Gills -form form pharynges slits in embryo  

-gills hang from skeletal supports (large surface area maximizes efficiency of gas exchange  B. later line system = 7  

pits with sensory hairs detect changes in water pressure  

-sense vibrations by other organisms to help in locating prey (or avoiding predators)  -this is also present in some amphibians  

*some species detect or even produce electricity  


-electric eel l  

-electric catfish

A. Cartilaginous Fish  

-it includes sharks and rays  

-Sharks: streamlined, powerful swimmers  

-Ray: flattened “dorsoventrally”  

-shark skin reduces drag, allowing greater speed  

-sharks nostrils are JUST for spell, not breathing  

-sharks skin can be made into swim suits  

-shark reproduction may be:  

Oviparous: lay eggs that hatch outside of the female (BIRDS)  

Ovoviviparous: eggs remain in oviduct, fed by egg yolk, then hatch and are released (Sharks)  

Viviparous: young develop in female’s uterus; some receive nourishment from mother’s uterine  blood or placenta (HUMANS, SHARKS, NOT MANY)  

B. Bony Fish

-most speciose vertebrate class  

 1. bony skeleton

 2. EX: rainbow trout and catfish  

 3. flap over gills: moves water and hence glass  


Tuesday, October 20, 2015  

Tuesday, October 20, 2015 4. swim bladder: gases moved to or from blood to control buoyancy  

5. most covered in overlapping scales and secrete mucus from skin glands to reduce drag when  swimming  


-vertebrates (w/ jaws)  

-4 appendages, more terrestrial = tetrapods  


1.salamanders = tailed even as adults  

2. frogs/toads= no tail as adults  


 1. tadpoles grilled frog larvae  

 2. adult moist terrestrial  

 3. gas exchange in lungs and through skin (this makes them very burnable to pollution and  the environmental changes)  

 4. lateral line system - system (like fish) in most larvae and some adults   5. -egg in jelly, no shell  

-keeps eggs moist in amniotes, extra embryonic membranes and shell do this 6. external  fertilization  


A. includes lizards and snakes (no lizards or venomous species in DeKalb) ON THE TEST: SNAKES ARE TETRAPODS

2. Turtles

-shell includes some vertebrae and ribs

3. Alligators: broader snout

Crocodiles: skinnier snout  



1. Dry scales made of keratin - on human fingers  

-reduces dehydration  

2. common in deserts  

3. gas exchange via lungs that move by moving ribs  

-fish and reptile scales develop from different layers of skin:  

{fish sales develop from dermis, reptile scales from epidermis}  

EX: analogous traits, via convergent evolution  

4. leathery shell forms inside mother =most are oviparous, although a few are viviparous)  5. internal fertilazation  

6. ectothermic: body heat primary from environment vs. from form metabolism in birds and  mammals)  

*remember that amniote phylogeny is paraphyletic


-without birds “reptiles” are paraphyletic  

-“Reptilia” includes birds and traditional reptiles are often called “non-avian reptiles”  AVES = Birds:  

1. Feathers  

a. for flight feather + insulation  

b. made of keratin like “reptile” scales  

2. Wings = modified forelimbs  

3. flight muscles attach to keeled sternum  

Evidence of bird- non-avian reptile relatedness  


1. Extant bird traits  

2. a. egg is amniotic -(like reptile)  

3. b. scales on legs  

Example: Cassowary, from Papua New Guinea and northern Australia  -Archaeopteryx = transitional fossils  

a. bird traits  

b. EX: feathers  

c. reptile traits  

d. EX: teeth long tail, abdominal ribs  

e. traits in between birds + non-avian reptiles: amount fusion in limbs  -in last 20 years, 100’s of transitional fossils of “feathered dinosaurs” found mostly in China

-these help clarify bird dinosaur relationships: birds are living dinosaurs  


-many bird characteristics are adaptions for flight : reduce weight  

1. No teeth ; instead, gizzard = muscular grinder in gut  

2. usually only 1 functioning ovary  

3. hollow bones : light weight but rigid  

-many birds characteristics are: adaptations for light: efficient metabolism  1. Lungs with many air sacs and one-way airflow to maximize )2 absorption  2. 4-chambered heart separates O2-rich and poor blood (like in mammals, but proportionally  larger)  

3. endothermic: metabolism creates heat and maintains relatively constant body temperature:  homeothermic  

Other flight adaptations:  

-bird brain: well developed vision, motor coordination  

-huge pectoral muscles (attach to large sternum) -25 percent of total bodyweight in some species  


-hair made of keratin  

EX: whiskers or fur - (provides insulation)  

-mammary glands- milk  

-diaphragm = muscular sheet between thorax + abdomen  

-relax- air pushed out of lungs

-contract - air sucked in  

Internal Fertilization  

-“live” birth not an egg except  


-have a four chambered heart  

-make own heat: endothermic  

-has constant temp: homeothermic  

-teeth: incisors, canines, premolar, molars  

Tooth Pattern  

-incisors, canines, premolar, molars  


Cheetah: big, sharp canoes and premolars to cut and tear flesh  

Bison: ….Herbivore, no incisors or canines (top) ; broad, flat premolars and molars to grind  plants  

-fleshy external ears in many mammals, hearing is important  

-secondary plates:  

separate food and air paths  

prey in mouth and still breath  

chew longer; suckle and breathe (vs. most reptiles)  

-many transitional fossils in between reptiles and mammals  

-jaw bone of early mammal-like reptiles function as inner ear bones in modern mammals:  exaptation


-egg laying mammals  

a. platypus + echidnas  

b. only in Australia and New Guinea  

c. Reptile like amniote eggs with leathery shell  


a. kangaroos, koalas, opossums  

b. mostly in Australia  

c. very short development in mother: on yolk sac and simpler placenta  d. completes development in external ouch: marsupium  

e. offspring much larger time nursing and much shorter proportion in gestation (in the uterus)  Eutherians “placental mammals”  

a. majority of mammal species 94 percent  

b. longer development in womb = in uterus  

c. well-developed placenta =  

complex of mother’s uterine lining and extra embryonic membranes exchange nutrients, gases,  and waste  


-hands (usually feet) adapted for grasping  

-forward-facing eyes (binocular vision)  

-in monkeys and apes, opposable thumb - like humans  

-can touch tips of all other fingers, allowing great dexterity and ability to grip

-adaptations for an arboreal (tree-dwelling) lifestyle  

Monkeys vs. Apes  

-monkeys have a tail  

-apes do not have a tail  

-New World Monkeys (South and Central America) have prehensile tail  

-Old World Monkeys (Africa and and Asia) do not  

Human evolutionary origins ……not a simple linear progression  

-more like a bush than a line  

-at times, more than one species in genus homo or australopithecus existed simultaneously  -Humans did NOT evolve from chimps!  

-humans share common ancestry with chimps (bonobo clade)  

(Microevolution in humans)  

-occurs by all 4 mechanisms of evolution:  

1. mutation  

2. gene flow  

3. random genetic drift  

4. natural selection  


-high incidence in Amish in Lancaster County, PA (0.5 % vs. .0017% in U.S.) but not so in other  Amish populations due to genetic drift founder effect  

-Ellis-van Creveld Syndrome …..allele affects skeletal development  

-includes polydactyly (rare in general population-amish people in Pennsylvania

-Founder Effect: type of random genetic drift  

-CNGB3 mutation- hereditary achromatopsia incidence: 5-10% on Pingelap island; 0.003% in  US  

-Why higher incident on this island?  

1775 hurricane-population reduced to about 20!  

-included a male who just happened to have thus mutation EX: at higher incidence via random  genetic drift  

(Natural Selection)  

-Sickle-cell in humans:  

one recessive allele (H) causes red blood cells to become misshapen in capillaries  -Homozygous (H) (H) individuals suffer from sickle-cell anemia, often with series health  problems  

BUT heterozygous (H) (H) individuals are protected against malaria  

-Natural selection (heterozygote advantage) maintained the (H) allele in populations where  malaria was common  

-because of gene flow, (H) sidle-cells alleles are present in populations where malaria isn’t a  problem  

-CDC estimates that 100,000 americans have sickle-cell disease =heterozygous for the recessive  allele  

-1/500 African-American births  

-1/36,000 Hispanic-American Births  

-also occurs in Americans with ancestors from India, Saudi Arabia, Turkey, Greece, Italy

-Sick-cell allele will probably never disappear because of gene flow  

-medicines allows us to “escape” some natural selection  

Natural Selection Requires:  

1.Heritable genetic variation  

2. differences in phenotype as a result of that variation  

3. differences in fitness as a result of those phenotypes  

-medicine can eliminate or reduce #2 or #3  

(Natural Selection Continued)  

-not all humans can digest milk as an adult  

-lactase persistence = continuing to produce lactase, an enzyme that digests lactose  -if no lactose, digestive problems including diarrhea if consume milk - risk of dehydration  -so expect strongest selection for persistence where human populations relied on milk  (Tool Use)  

-Pre-1960, “only humans make and use tools”  

1960: Jane Goodall observes chimpanzees modyfying twigs to “fish” termites out of mounds and  eat them  

-chimps in Senegal repeatedly sharpened sticks and used them for hunting bush babies  -other animals use tools, although most don’t make them  

-EX: Woodpecker finches + New Caledonian Crows  

(Animal Behavior)  

What is behavior?

-behavior is action carried out by muscles (animals have them) under control of the nervous  system in response to a stimulus  

-this includes any external or internal factor that can influence an organism  - a cue that triggers a response by an organism  

*sponges do not have muscles, therefore this can not exhibit behavior  

-behavior is necessary for animals to regulate body temp and many other things:  -maintain homeostasis aka body temp.  

-acquire food  

-avoid predation  

-find or attract mates  

(Niko Tinbergen’s 4 Questions About Animal Behavior)  

1. What is the stimulus and how does the animal respond  

2. How does the animal’s experience (when growing or developing) influence the response?  *these are questions about proximate Causes “HOW”  

3. How does it help the animal survive and reproduce?  

-escape an unsuitable environment or to gain access to food resources needed to produce  offspring (Bird Migration)  

4. What is the evolutionary history of the behavior?  

*these are questions about the ultimate causes “WHY”  

Hypothesis: migration may have evolved as a way to take advantage of temporarily abundant  food resources

(Types of Stimuli)  


animal 1 signal animal 2  

= transmission of a signal (stimulus) by one animal and reception by another  4 modes of animal communication:  

visual- recover animals sees the signal  

auditory- sender animal makes a noise that is heard by the receiver  

tactile- animals touch each other- aggression or mating  

chemical- sender animal produces molecules that are sensed by the receiver -this is unused by  humans (MAX)  

-Drosophila: courtship behavior  

-if all signals check out they will mate  

*important to mate with same species  

Ex: Worker Bees communicate when food is near and tell how far  



Blue Jay calls to warn other birds of a predator: auditory  

in schools of fish, injuries to fish skin release molecules that others senses: chemical  tadpoles eat aquatic plants  

when dragonfly larvae (predators) are present tadpoles eat less and grow less  Experiment: predators cages and tadpoles can’t see it  

Result: tadpoles still don't eat and grow as much

Conclusion: tadpoles sense chemical signals of predator  

-stimulus may start a fixed action pattern - a series of “programmed” behaviors in response to a  stimulus, even if stimulus stops  

EX: Goose  

“retrieving” absent egg (can’t control it)  

EX: Mallard Duck  

continues courting after female leaves  

*remember goose with egg and ball experiment  








-Crown-of thorn sea star  


-Water Vascular System  




-Cartilaginous Fish

-bony fish  



-lateral line system  -pharyngeal slits  -oviparous  












-radially symmetrical  -vertebrates  


-Platyhelminthes  -metanephridia


-fix action pattern  



-Niko Tinbergen  


-tool use  

-founder effect  

-4 mechanics of evolution  -old and new world monkey  -primates  

-bilaterally symmetrical  -cephalization  










-coral reef  



-protonephridia  -septae  

-segmented worms  -mollusks  





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