Chapter 10 - Digestion Flashcards
animals are
heterotrophic or autotrophic
heterotrophic
because animals are heterotrophic, they
are unable to synthesize their own nutrients
food provides raw material for
energy
repair
growth of tissues
in order to get energy, repair and growth of tissues, food must be
ingested
digestion
degradation of large molecules into smaller molecules
the degradation of large molecules into smaller molecules allows for their
absorption into the bloodstream
once these smaller molecules are absorbed into the bloodstream, they can be
used directly by cells
intracellular digestion
occurs within the cell
usually in membrane-bound vesicles
extracellular digestion
digestive process that occurs outside of the cell
within a lumen or tract
in unicellular organisms, food capture is primarily via
phagocytosis
immediately following food ingestion, ____ form
unicellular organisms
food vacuoles
in the amoeba (unicellular), _____ surround and engulf food
pseudopods
phagocytosis
surround and engulf (food)
once pseudopods surround and engulf food, (amoeba)
enclose it in food vacuoles
lysosomes contain
digestive enzymes
lysosomes fuse with the
amoeba
food vacuole
once lysosomes fuse with the food vacuole, they
amoeba
release their digestive enzymes
the digestive enzymes of the lysosome act upon the
amoeba
nutrients in the food vacuoles
after the enzymes act upon the nutrients in the food vacuoles, the simpler molecules
(amoeba)
diffuse into the cytoplasm
the unusable end-products are
amoeba
eliminated from the vacuole
in the paramecium (unicellular)-
_____ sweep food into the oral groove and cytopharynx
cilia
____ forms around food at the lower end of the cytopharynx
paramecium
food vacuole
after food vacuole forms around the food at the lower end of the cytopharynx,
(paramecium)
the vacuole breaks off into the cytoplasm
after the food vacuole breaks off into the cytoplasm,
paramecium
it progresses towards the anterior end of the cell
_____ are secreted into the vacuole
paramecium
enzymes
after enzymes are secreted into the vacuole
paramecium
the products diffuse into the cytoplasm
solid wastes are expelled at the
paramecium
anal pore
physical breakdown of food begins with
cutting and grinding in the mouth
and
churning in the digestive tract
after physical breakdown, the molecular composition is ______
unchanged
physical breakdown of large particles of food to small particles provides a
greater surface area of the substrates for the enzymes to act on
chemical breakdown of molecules is accomplished by
enzymatic hydrolysis
the smaller digested nutrients are able to
pass through the semi-permeable plasma membrane of the gut cells
examples of smaller digested nutrients
glucose
fatty acids
amino acids
glycerol
after the smaller digested nutrients pass through the semi-permeable plasma membrane of the gut cells, they are
further metabolized or transported
the hydra (cnidarians) uses _____ and ____ for digestion
intracelllular;
extracellular
_____ bring food to the mouth (ingestion)
hydra
tentacles
after the tentacles bring the food to the mouth
hydra
they release the particles into a cup-like sac
gastrovascular cavity lined with
endodermal cells
endodermal cells that line the gastrovascular cavity secrete
enzymes into the cavity
digestion mostly occurs
outside the cells (extracellular)
once the food is reduced to small fragments, the ____ engulf the nutrients
gastrodermal cells
once the gastrodermal cells engulf the nutrients
digestion is completed intracellularly
undigested food is
expelled through the mouth
every cell is exposed to the
external environment
intracellular digestion is facilitated by the fact that
every cell is exposed to the external environment
annelids, like higher animals have a
one-way digestive tract
one-way digestive tract includes
annelids
both mouth and anus
one-way digestive tract allows for
annelids
specialization of different parts of the digestive tract for different functions
digestive tract parts include
annelids
mouth pharynx espohagus crop gizzard intestine anus
crop
annelids
store food
gizzard
annelids
grind food
intestine
annelids
contains large dorsal fold (typholosole) to provide increased surface area for digestion and absorption
typholosole
annelids
large dorsal fold in the intestine
provides increased surface area for digestion and absorption
soluble food passes by ____
annelids
diffusion
solid food passes by diffusion through
annelids
walls of small intestine into blood
insects (arthropods) have a digestive system similar to a
earthworm (annelids)
insects (arthropods), in addition to the parts of the earthworm, have
salivary glands (digestive glands)
salivary glands (digestive glands) in arthropods (insects) improve
food digestion
the human digestive tract begins with the
oral cavity
human digestive tract components
oral cavity pharynx esophagus stomach small intestine large intestine anus
accessory organs of the human digestive tract are
salivary glands
pancreas
liver
gall bladder
accessory glands play essential role in
digestion
the oral cavity (mouth) is where ____ begins
mechanical and chemical digestion of food begins
mechanical digestion
breakdown of large food particles into smaller particles
through mastication
mastication
biting and chewing action of teeth
chemical digestion
enzymatic breakdown of macromolecules into smaller molecules
chemical and mechanical digestion both begin in the
mouth
chemical digestion begins in the mouth when
salivary glands secrete saliva
saliva
lubricates food to facilitate swallowing
provides a solvent for food particles
saliva is secreted in response to
nervous reflex triggered by presence of food in the oral cavity
nervous reflex which secretes saliva is triggered by
presence of food in the oral cavity
saliva contains the enzyme
salivary amylase (ptyalin)
salivary amylase (ptyalin)
hydrolyzes starch to maltose
maltose is a type of
disaccharide
esophagus
muscular tube leading from mouth to the stomach
food is moved down the esophagus by
rhythmic waves of involuntary muscular contractions called peristalsis
peristalsis
rhythmic waves of involuntary muscle contractions
stomach
description
large
muscular organ
stomach
location
upper abdomen
stomach ____ and _____ food
stores;
partially digests
walls of the stomach are lined by the
thick gastric mucosa
thick gastric mucosa which lines stomach contains
glands
glands of the thick gastric mucosa secrete
mucus
mucus secreted by glands of thick gastric mucosa
protect stomach lining from harshly acidic juices (pH = 2) in the stomach
in addition to mucus, glands of stomach also secrete
pepsin;
HCl
pepsin
protein-hydrolyzing enzyme
HCl
kills bacteria
dissolves intercellular “glue” holding food tissues together
activates certain proteins
churning of the stomach produces
chyme
chyme
acidic, semi-fluid mixture of partially digested food
after produced in stomach, chyme passes into
first segment of small intestine, the duodenum, through the pyloric sphincter
duodenum
first segment of small intestine
chemical digestion is completed in the
small intestine
the small intestine is divided into ___ sections
3
3 sections of the small intestine
duodenum
jejunum
ileum
the small intestine is highly adapted to ____
absorption
the intestine is extremely long and highly coiled in order to
maximize surface area available for digestion and absorption
length of intestine
greater than 6 meters
villi
numerous finger-like projections that extend out of the intestinal wall
villi contain
capillaries and lacteals
lacteals
vessels of the lymphatic system
amino acids and monosaccharides pass through the _____ into the _____
villi walls;
capillary system
large fatty acids and glycerol pass into the
lacteals
after the large fatty acids and glycerol pass into the lacteals, they are
reconverted into fats
fat =
fatty acid + glycerol
some nutrients are _____ while others are _____ in the intestine
actively absorbed;
passively absorbed
active absorption means
requires energy
nutrients that are actively absorbed in the intestine
glucose;
amino acids
most digestion in the small intestine occurs in the
duodenum
in addition to most digestion, the duodenum is the site where secretions from the ___, ____. ____, ____ mix together with the _____ entering from the _____
intestinal glands, pancreas, liver, gall bladder acidic chyme entering; stomach
intestinal mucosa secretes (3)
lipases
aminopeptidases
disaccharides
lipases secreted from intestinal mucosa for
enzyme for fat digestion
aminopeptidases secreted from intestinal mucosa for
enzymes for polypeptide digestion
disaccharides secreted from intestinal mucosa for
digestion of maltose, lactose, sucrose
lactase
disaccharide
breaks down lactose (milk sugar)
lactase is present in ____ but many ____ lack the enzyme
infants;
adults
those who lack lactase are
lactose intolerant
lactose in the small intestine
cannot be digested
since lactose in the small intestine cannot be digested, it is
metabolized by bacteria
the metabolism of lactose by bacteria in the small intestine causes
intestinal discomfort
because animals are heterotrophic, they
are unable to synthesize their own nutrients
food provides raw material for
energy
repair
growth of tissues
in order to get energy, repair and growth of tissues, food must be
ingested
digestion
degradation of large molecules into smaller molecules
the degradation of large molecules into smaller molecules allows for their
absorption into the bloodstream
once these smaller molecules are absorbed into the bloodstream, they can be
used directly by cells
intracellular digestion
occurs within the cell
usually in membrane-bound vesicles
extracellular digestion
digestive process that occurs outside of the cell
within a lumen or tract
in unicellular organisms, food capture is primarily via
phagocytosis
immediately following food ingestion, ____ form
unicellular organisms
food vacuoles
in the amoeba (unicellular), _____ surround and engulf food
pseudopods
phagocytosis
surround and engulf (food)
once pseudopods surround and engulf food, (amoeba)
enclose it in food vacuoles
lysosomes contain
digestive enzymes
lysosomes fuse with the
amoeba
food vacuole
once lysosomes fuse with the food vacuole, they
amoeba
release their digestive enzymes
the digestive enzymes of the lysosome act upon the
amoeba
nutrients in the food vacuoles
after the enzymes act upon the nutrients in the food vacuoles, the simpler molecules
(amoeba)
diffuse into the cytoplasm
the unusable end-products are
amoeba
eliminated from the vacuole
in the paramecium (unicellular)-
_____ sweep food into the oral groove and cytopharynx
cilia
____ forms around food at the lower end of the cytopharynx
paramecium
food vacuole
after food vacuole forms around the food at the lower end of the cytopharynx,
(paramecium)
the vacuole breaks off into the cytoplasm
after the food vacuole breaks off into the cytoplasm,
paramecium
it progresses towards the anterior end of the cell
_____ are secreted into the vacuole
paramecium
enzymes
after enzymes are secreted into the vacuole
paramecium
the products diffuse into the cytoplasm
solid wastes are expelled at the
paramecium
anal pore
physical breakdown of food begins with
cutting and grinding in the mouth
and
churning in the digestive tract
after physical breakdown, the molecular composition is ______
unchanged
physical breakdown of large particles of food to small particles provides a
greater surface area of the substrates for the enzymes to act on
chemical breakdown of molecules is accomplished by
enzymatic hydrolysis
the smaller digested nutrients are able to
pass through the semi-permeable plasma membrane of the gut cells
examples of smaller digested nutrients
glucose
fatty acids
amino acids
glycerol
after the smaller digested nutrients pass through the semi-permeable plasma membrane of the gut cells, they are
further metabolized or transported
the hydra (cnidarians) uses _____ and ____ for digestion
intracelllular;
extracellular
_____ bring food to the mouth (ingestion)
hydra
tentacles
after the tentacles bring the food to the mouth
hydra
they release the particles into a cup-like sac
gastrovascular cavity lined with
endodermal cells
endodermal cells that line the gastrovascular cavity secrete
enzymes into the cavity
digestion mostly occurs
outside the cells (extracellular)
once the food is reduced to small fragments, the ____ engulf the nutrients
gastrodermal cells
once the gastrodermal cells engulf the nutrients
digestion is completed intracellularly
undigested food is
expelled through the mouth
every cell is exposed to the
external environment
intracellular digestion is facilitated by the fact that
every cell is exposed to the external environment
annelids, like higher animals have a
one-way digestive tract
one-way digestive tract includes
annelids
both mouth and anus
one-way digestive tract allows for
annelids
specialization of different parts of the digestive tract for different functions
digestive tract parts include
annelids
mouth pharynx espohagus crop gizzard intestine anus
crop
annelids
store food
gizzard
annelids
grind food
intestine
annelids
contains large dorsal fold (typholosole) to provide increased surface area for digestion and absorption
typholosole
annelids
large dorsal fold in the intestine
provides increased surface area for digestion and absorption
soluble food passes by ____
annelids
diffusion
solid food passes by diffusion through
annelids
walls of small intestine into blood
insects (arthropods) have a digestive system similar to a
earthworm (annelids)
insects (arthropods), in addition to the parts of the earthworm, have
salivary glands (digestive glands)
salivary glands (digestive glands) in arthropods (insects) improve
food digestion
the human digestive tract begins with the
oral cavity
human digestive tract components
oral cavity pharynx esophagus stomach small intestine large intestine anus
accessory organs of the human digestive tract are
salivary glands
pancreas
liver
gall bladder
accessory glands play essential role in
digestion
the oral cavity (mouth) is where ____ begins
mechanical and chemical digestion of food begins
mechanical digestion
breakdown of large food particles into smaller particles
through mastication
mastication
biting and chewing action of teeth
chemical digestion
enzymatic breakdown of macromolecules into smaller molecules
chemical and mechanical digestion both begin in the
mouth
chemical digestion begins in the mouth when
salivary glands secrete saliva
saliva
lubricates food to facilitate swallowing
provides a solvent for food particles
saliva is secreted in response to
nervous reflex triggered by presence of food in the oral cavity
nervous reflex which secretes saliva is triggered by
presence of food in the oral cavity
saliva contains the enzyme
salivary amylase (ptyalin)
salivary amylase (ptyalin)
hydrolyzes starch to maltose
maltose is a type of
disaccharide
esophagus
muscular tube leading from mouth to the stomach
food is moved down the esophagus by
rhythmic waves of involuntary muscular contractions called peristalsis
peristalsis
rhythmic waves of involuntary muscle contractions
stomach
description
large
muscular organ
stomach
location
upper abdomen
stomach ____ and _____ food
stores;
partially digests
walls of the stomach are lined by the
thick gastric mucosa
thick gastric mucosa which lines stomach contains
glands
glands of the thick gastric mucosa secrete
mucus
mucus secreted by glands of thick gastric mucosa
protect stomach lining from harshly acidic juices (pH = 2) in the stomach
in addition to mucus, glands of stomach also secrete
pepsin;
HCl
pepsin
protein-hydrolyzing enzyme
HCl
kills bacteria
dissolves intercellular “glue” holding food tissues together
activates certain proteins
churning of the stomach produces
chyme
chyme
acidic, semi-fluid mixture of partially digested food
after produced in stomach, chyme passes into
first segment of small intestine, the duodenum, through the pyloric sphincter
duodenum
first segment of small intestine
chemical digestion is completed in the
small intestine
the small intestine is divided into ___ sections
3
3 sections of the small intestine
duodenum
jejunum
ileum
the small intestine is highly adapted to ____
absorption
the intestine is extremely long and highly coiled in order to
maximize surface area available for digestion and absorption
length of intestine
greater than 6 meters
villi
numerous finger-like projections that extend out of the intestinal wall
villi contain
capillaries and lacteals
lacteals
vessels of the lymphatic system
amino acids and monosaccharides pass through the _____ into the _____
villi walls;
capillary system
large fatty acids and glycerol pass into the
lacteals
after the large fatty acids and glycerol pass into the lacteals, they are
reconverted into fats
fat =
fatty acid + glycerol
some nutrients are _____ while others are _____ in the intestine
actively absorbed;
passively absorbed
active absorption means
requires energy
nutrients that are actively absorbed in the intestine
glucose;
amino acids
most digestion in the small intestine occurs in the
duodenum
in addition to most digestion, the duodenum is the site where secretions from the ___, ____. ____, ____ mix together with the _____ entering from the _____
intestinal glands, pancreas, liver, gall bladder acidic chyme entering; stomach
intestinal mucosa secretes (3)
lipases
aminopeptidases
disaccharides
lipases secreted from intestinal mucosa for
enzyme for fat digestion
aminopeptidases secreted from intestinal mucosa for
enzymes for polypeptide digestion
disaccharides secreted from intestinal mucosa for
digestion of maltose, lactose, sucrose
lactase
disaccharide
breaks down lactose (milk sugar)
lactase is present in ____ but many ____ lack the enzyme
infants;
adults
those who lack lactase are
lactose intolerant
lactose in the small intestine
cannot be digested
since lactose in the small intestine cannot be digested, it is
metabolized by bacteria
the metabolism of lactose by bacteria in the small intestine causes
intestinal discomfort
the liver produces
bile
after the liver produces bile, it is stored in the
gall bladder
the bile is stored in the gall bladder prior to
release into the small intestine
bile contains no
enzymes
bile emulsifies
fats
bile emulsifies fats, which means it
breaks down large globules into small droplets
emulsification of fats
exposes a greater surface area of the fat
the emulsification of fats exposes a greater surface area of the fat to the
pancreatic lipase
in the absence of bile, fats
cannot be digested
the pancreas produces
enzymes
examples of enzymes produces by the pancreas
amylase
trypsin
lipase
amylase is for digestion of
pancreas
carbs
trypsin is for digestion of
pancreas
proteins
lipase is for the digestion of
pancreas
fats
the pancreas secretes
bicarbonate rich juice
the bicarbonate rich juice secreted by the pancreas
neutralizes acidic chyme arriving from stomach
pancreatic enzymes operate optimally at ____ pH
higher (8.5) - slightly alkaline
the large intestine is appx ___ long
1.5 meters
the large intestine functions in the absorption of
salts and any water not already absorbed by small intestine
rectum
large intestine
transient storage of feces prior to elimination through anus
plants have ___ digestive system
no
although plants have no digestive system, _____ processes do occur
intracellular digestive
intracellular digestion in plants coordinates
utilization of nutrients with their production
plants store ___, ___, ___, ____ in the cell
polymers
starches
lipid
proteins
the principle storage food in plants is
starge
starch is a type of
glucose polysaccharide
starch is found in large quantities in the ___, ____, ___ parts of the plant
seeds
stems
roots
storage polymers are broken down to simpler molecules when
nutrients are required
storage polymers are broken down into these types of simpler molecules
glucose
fatty acids
glycerol
amino acids
storage polymers are broken down to simpler molecules by
enzyme hydrolysis
the simple products (glucose, fatty acids, glycerol, amino acids) can be used
in the storage cell itself
or
transported by diffusion to other cells
if the simple products are to be used by other cells, they are transported via
diffusion
some heterotrophic organisms (e.g. fungi) must _______ from the environment
obtain preformed organic molecules (nutrients)
in order to obtain the nutrients from the environment,
fungi
enzymes are secreted
the secreted enzymes are able to
hydrolyze complex nutrients into simpler molecules
the simple molecules that have been hydrolyzed from complex nutrients by enzymes can be used for
energy to synthesize larger molecules
rhizoids
fungus of bread mold
typical saprophyte which lives on dead organic material
the rhizoids do this to bread
secrete enzymes (onto external environment)
digestion produces
simple soluble end-products
simple soluble end-products produces by digestion
glucose
amino acids
fatty acids
glycerol
simple soluble end-products are then
absorbed by diffusion into rhizoid
after the simple soluble end-products are absorbed by diffusion into the rhizoid,
they are transported throughout the mold
venus flytrap (extracellular digestion)
comes closest to ingestion in the plant kingdom
when a fly arrives, certain sensitive tissues
entrap the insect
after the sensitive tissues of the venus flytrap have entrapped the insect,
enzymes are secreted to digest the fly and absorb the soluble end products
enzymes are secreted by the venus flytrap in order to
digest the fly and absorb the soluble end products
the venus fly trap is a ____troph
auto
the venus flytrap is an autotroph because
photosynthesizes to produce glucose
the venus flytrap uses the insect as a
nitrate sources
the venus flytrap uses the insect as a nitrate source because
the flytrap grows in nitrogen-poor soil
the liver produces
bile
