A&P 2: Chapter 24 and 25 (Digestive, Nutrition)
HDL, 40-60 mg/dL
"Good" cholesterol? Ideal level?
ADP
(Adenosine Diphosphate) The compound that remains when a phosphate group is removed from ATP, releasing energy
ATP
(adenosine triphosphate) main energy source that cells use for most of their work
Ketone bodies
-Compounds produced during the incomplete breakdown of fat when glucose is not available in the cells. -Used for energy by extrahepatic (non-liver) tissues, e.g. muscle & brain during adapted starvation -In extrahepatic tissues, are converted back into Acetyl CoA through the TCA cycle to produce energy -can be used as an energy source when CHO is low and helps to conserve blood glucose
aging and the digestive system
-Decreased secretory mechanisms and motility -Loss of strength and tone of digestive muscular tissue -Changes in neurosecretory feedback -Diminished response to pain and internal sensations
ketosis
-Occurs during uncontrolled Diabetes mellitis, fasting/starvation, very low CHO diet -Ketone concentration rises during accelerated FA oxidation -Occurs during conditions when fat oxidation is overly active or CHO intake is low or impaired = accumulation of Acetyl-CoA -Because Acetyl CoA is present in larger amounts, the extra Acetyl CoA is used to produce ketones
triacylglycerols
-composed of 3 fatty acids bonded by ester linkages to glycerol - nonpolar and hydrophobic -used for energy storage -more reduced than carbohydrates --> oxidation of TAG yields twice more energy -stored as fat globules in adipose tissue
Krebs Cycle (Citric Acid Cycle)
2 Acetyl CoA ---> 2ATP + 6NADH + 2FADH2 + 4CO2; occurs in Matrix of Mitochondria
Cytochrome b-c1 complex
2nd of the 3 electron-driven proton pumps in respiratory chain. It accepts electrons from ubiquinone
longitudinal, circular, oblique
3 muscle layers of the stomach
right, left, caudate, quadrate
4 lobes of the liver
glycolysis, glycogenesis, glycogenolysis, gluconeogenesis
4 processes of carbohydrate metabolism
fatty liver disease
A buildup of lipids that are deposited in the liver tissue
Redox reaction
A chemical reaction involving the transfer of one or more electrons from one reactant to another; also called oxidation-reduction reaction.
esophagus
A collapsible tube that extends from the pharynx to the stomach; contractions of the muscle in the wall of the esophagus propel food and liquids through it to the stomach
unsaturated fats
A fat that is liquid at room temperature and found in vegetable oils, nuts, and seeds.
saturated fats
A fat that is solid at room temperature and found in animal fats, lards, coconut oil, and dairy products.
prostaglandins
A group of bioactive, hormone-like chemicals derived from fatty acids (arachidonic acid) that have a wide variety of biological effects including roles in inflammation, platelet aggregation, vascular smooth muscle dilation and constriction, cell growth, protection of from acid in the stomach, and many more.
Vitamin A
A group of fat-soluble compounds which includes beta-carotene and that are important for growth and development, for the maintenance of the immune system and good vision
cholesterol
A lipid that forms an essential component of animal cell membranes and acts as a precursor molecule for the synthesis of other biologically important steroids and bile salts
glycolysis
A metabolic process that breaks down carbohydrates and sugars through a series of reactions to either pyruvic acid or lactic acid and release energy for the body in the form of ATP
Beta oxidation
A metabolic sequence that breaks fatty acids down to two-carbon fragments that enter the citric acid cycle as acetyl CoA.
phospholipids
A molecule that is a constituent of the inner bilayer of biological membranes (cell membrane, myelin sheath), having a polar, hydrophilic head and a nonpolar, hydrophobic tail.
stomach
A muscular and elastic sac that serves mainly to store food, break it up mechanically, and begin chemical digestion of proteins and fat.
salivary amylase
A salivary gland enzyme that hydrolyzes starch.
Electron Transport Chain (ETC)
A sequence of electron carrier molecules (membrane proteins) that shuttle electrons during the redox reactions that release energy used to make ATP.
rectum
A short tube at the end of the large intestine where waste material is compressed into a solid form before being eliminated
appendix
A small, fingerlike extension of the vertebrate cecum; contains a mass of white blood cells that contribute to immunity.
mass peristalsis
A strong peristaltic wave that begins in the transverse colon and quickly drives the contents of the colon into the rectum.
intrinsic factor
A substance produced by the mucosa of the stomach and intestines that is essential for the absorption of vitamin B12.
bolus
A term used to describe food after it has been chewed and mixed with saliva
dietary fiber
A tough complex carbohydrate (polysaccharide) that the body cannot digest; include cellulose and pectin
sterols
A type of lipid based on cholesterol; includes testosterone and estrogen; compounds containing a four-ring carbon structure with any of a variety of side chains attached.
Vitamin B
A vitamin that acts as a coenzyme in the conversion of glucose to ATP.
Vitamin D
A vitamin that is manufactured in the skin after exposure to sunlight.
deciduous dentition
Also known as baby teeth or milk teeth, this is the first set of teeth, which form in utero and erupt shortly after birth.
protein metabolism
Amino acids are either oxidized to produce ATP or used to synthesize new proteins Excess dietary amino acids are not excreted but converted into glucose (gluconeogenesis) or triglycerides (lipogenesis)
essential amino acids
Amino acids that are needed, but cannot be made by the body; they must be eaten in foods
3L
Amount of gastric juice produced each day
nitrogen homeostasis
Amount of nitrogen ingested in proteins equals the amount excreted in urine/feces
nicotinamide adenine dinucleotide (NAD+)
An energy carrier that accepts electrons and feeds them into the electron transport chain
glycogen
An extensively branched glucose storage polysaccharide found in the liver and muscle of animals; the animal equivalent of starch.
pancreas
An organ in the abdominal cavity with two roles. The first is an exocrine role: to produce digestive enzymes and bicarbonate, which are delivered to the small intestine via the pancreatic duct. The second is an endocrine role: to secrete insulin and glucagon into the bloodstream to help regulate blood glucose levels.
gall bladder
An organ that stores bile and releases it as needed into the small intestine
coenzymes
An organic molecule that is a necessary participant in some enzymatic reactions; helps catalysis by donating or accepting electrons or functional groups; e.g., a vitamin, ATP, NAD+.
Trans fats
An unsaturated fat, formed artificially during hydrogenation of oils, containing one or more trans double bonds.
10 inches
Approximately how long is the esophagus?
molars
Back teeth that grind food
paleolithic diet
Based on the foods ancient ancestors might likely have eaten, such as meat, nuts, and berries.
Digestive system
Breaks down food into smaller molecules. Absorbs these nutrients into the body.
Disaccharides
Carbohydrates that are made up of two monosaccharides
common bile duct
Carries bile from the liver and gallbladder to the duodenum. Also called the choledochus.
Exocrine
Category of glands to which the salivary glands belongs.
proteins, glycerol portion of triglycerides, lactic acid, amino acids (some)
Compounds that can be used for gluconeogenesis
Ketones
Concentration of ______________ rises during accelerated fatty acid oxidation.
pyruvate oxidation
Conversion of pyruvate to acetyl CoA and CO2 that occurs in the mitochondrial matrix in the presence of O2.
gastric pits
Deep infoldings in the walls of the stomach lined with secretory cells.
regulation of metabolism
Depends on chemicals in the cells, signals from the nervous and endocrine systems, and time elapsed since the last meal.
low carb diet
Diet consisting of: High protein (>50%); Mod. fat (30%); Low carb (<20%)
Atkins and ketogenic diets
Diets consisting of: High fat (65%); Mod. protein (35%); Low carb (5%)
cystic duct
Duct leading from the gallbladder to the common bile duct; carries bile
2 minutes
Duration of activity in which primarily anaerobic respiration is performed
Gluten free diet
Eliminates wheat, oats, rye, barley and their derivatives; treatment for celiac disease
lipids
Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.
amylase
Enzyme in saliva that breaks the chemical bonds in starches
nucleases
Enzymes that break down nucleic acids
brush border enzymes
Enzymes that complete carbohydrate and protein digestion that are produced by the plasma membrane of microvilli
villi
Fingerlike extensions of the intestinal mucosa that increase the surface area for absorption; largest in the duodenum, decrease in size along the S.I., contain a dense capillary bed and lacteal capillary, digested food is absorbed through epithelial cells and inter the capillary beds and lacteals.
2
For each glucose molecule, how many times does the krebs cycle repeat?
ingestion, secretion, mixing and propulsion, digestion, absorption, defecation
Functions of the digestive system
salivary glands
Glands of the mouth that produce saliva, a digestive secretion
insulin
Hormone that inhibits lipolysis
steroids
Hormones and hormone-like substances that share the same fat-soluble chemical structure (lipids in which the carbon skeleton contains four fused rings)
Cortisol, glucagon, thyroid hormones
Hormones that stimulate gluconeogenesis
catecholamines (epinephrine and norepinephrine), ACTH, GA
Hormones that stimulate lipolysis
.8 g per kg
How much protein should you consume on a daily basis?
alkaline tide
In gastric parietal cell, HCO3- leaves the cell in exchange for Cl- going in the cell.
liver
In this location, glycogen plays a role in regulation of blood glucose levels
muscle
In this location, glycogen serves as a rapidly mobilizable source of glucose to provide energy for contraction
lactate (lactic acid)
In this reaction, what molecule is reduced?
accessory digestive organs
Include structures that are not part of the GI tract, but they contribute to food processing. Include teeth, tongue, salivary glands, liver, gallbladder, pancreas
ingestion
Intake of food
defecation reflex
Involuntary response of intestinal contraction and anal sphincter relaxation to rectal distention -Rectal wall distends -Stretch receptors send sensory nerve impulses to the sacral spinal cord -Motor impulses travel back to the descending colon, sigmoid colon, rectum, and anus -Longitudinal rectal muscles contract and the internal anal sphincter opens -If the external anal sphincter is voluntarily relaxed, defecation occurs and the feces are expelled
Acetyl CoA
Involved in helping 2-carbon acetyl groups enter the Krebs cycle and the synthesis of lipids
Pyruvic acid
Involved in production of lactic acid, the production of alanine, and gluconeogenesis.
Glucose-6-phosphatase
Involved in the synthesis of glycogen, the release of glucose into the bloodstream, synthesis of nucleic acids, and glycolysis.
conjugate bases
Lactate and pyruvate are the _________________ _______________of lactic acid and pyruvic acid, respectively.
ATP synthase
Large protein (enzyme) that uses energy from H+ ions to bind ADP and a phosphate group together to produce ATP
emptying of stomach
Largely controlled by factors in duodenum (the beginning of the small intestines)
liver
Largest gland in the body consisting of 4 lobes; makes bile, which is important in the emulsification of fats.
serosa
Layer of the gastrointestinal tract (alimentary canal) that includes the visceral peritoneum and adventita in esophagus.
carbohydrates, lipids, proteins
List macromolecules that are metabolized by the liver
bile acids, sex hormones, adrenocortical hormones, vitamin D
List the major types of steroids.
mechanical digestion (small intestine)
Localized contractions (segmentation) and propulsive contractions (peristalsis) of the small intestines assists in the process of ____________________ __________________.
skeletal muscle, mucous membrane, papillae
Major components of the tongue
4, bone salts
Minerals comprise approximately ______ % of body weight and are primarily found in ________ _________.
nonpolar
Most lipids exhibit this property and results in them being insoluble in water.
gastroesophageal sphincter (cadiac sphincter)
Muscle that connects the esophagus and stomach, and helps keep the stomach contents in the stomach
2 ATP, 2 NADH, 2 pyruvic acid
Net products of glycolysis
blood supply of liver
Oxygenated blood from hepatic artery, and nutrient rich deoxygenated blood from hepatic portal vein---> hepatic sinusoids---> central vein ---> hepatic vein---> inferior vena cava--> right atrium of heart
chyme
Partially digested, semiliquid food mixed with digestive enzymes and acids in the stomach.
98%
Percent of energy reserves of triglycerides stored in adipose tissue.
5%
Percent of phospholipids and sterols that composes dietary lipids?
97-99.5%
Percent of saliva that is water
mechanical digestion
Physical breakdown of large pieces of food into smaller pieces
dentin
Primary material found in teeth. It is covered by the enamel in the crown and a protective layer of cementum in the root.
liver, muscle
Primary organ/tissue locations of glycogenesis and glycogenolysis
chemiosmosis
Process by which a Hydrogen pump pumps protons into the outer mitochondrial space. H+ passively flows through the ATP synthase which leads to the creation of ATP.
chemical digestion
Process by which enzymes break down carbohydrates, proteins, lipids, and nucleic acids into small molecules that the body can use
26-28 ATP, 6 H2O
Products of electron transport chain?
peristalsis (intestine)
Propulsive contractions that move material through the colon
incomplete proteins
Proteins that are missing one or more of the essential amino acids; found in plant sources such as nuts and legumes
functions of large intestine
Reabsorption of water Compaction of intestinal contents into feces Absorption of important vitamins produced by bacteria Storage of fecal material prior to defecation
cytoplasm
Relative to the cell, specific location of glycogenesis and glycogenolysis
Monosaccharides
Single sugar molecules
cementum
Specialized, calcified connective tissue that covers the anatomic root of a tooth.
Glycogen Metabolism
Storage and mobilization of glucose (glycogenesis and glycogenolysis)
Gums, hard palate, dorsum of tongue
Structures of the oral cavity that are slightly keratinized for extra protection.
nutrients
Substances in food that your body needs to grow, to repair itself, and to supply you with energy
atp, glycogen, amino acid, triglyceride
The body's use of glucose depends on the needs of cells for ________ production, _________ synthesis, ________ _______ synthesis, and _________ synthesis.
hepatic duct
The duct that leads from the liver to the common bile duct; transports bile.
NADH dehydrogenase complex
The first respiratory complex in the ETC that accepts electrons from NADH in the form of a hydride ion which is then converted into a proton and two high-energy electrons.
saliva
The fluid released when the mouth waters that plays an important role in both mechanical and chemical digestion
HCl production in stomach
The formation of an alkaline tide is a feature of what process?
gluconeogenesis
The formation of glucose from noncarbohydrate sources, such as amino acids (anabolic process)
Carbohydrates
The macromolecules that are broken down and empty out the quickest from the stomach (decreases satiety)
fats
The macromolecules that are broken down and empty out the slowest from the stomach (increases satiety)
kilocalories (kcals)
The measurement of energy in foods. Commonly referred to as calories.
phosphorylation
The metabolic process of introducing a phosphate group into an organic molecule.
Absorption (small intestine)
The movement of digested food molecules through the wall of the small intestines into the blood -Nutrients that are absorbed through the wall of the small intestine (villi) gets absorbed by the capillary network which comes together to form the hepatic portal vein
enteric nervous system
The nervous system of the gastrointestinal tract. It controls secretion and motility within the GI tract, and is linked to the central nervous system. Controls short reflexes.
small intestine
The part of the digestive system in which most chemical digestion takes place; Consists of the duodenum, jejunum, ileum
absorption
The process by which nutrient molecules pass through the wall of the digestive system into the blood and lymph (nutrition)
chemical digestion
The process in the mouth in which salivary amylase converts polysaccharides to disaccharides, lingual lipase begins the breakdown of fats.
secretion
The release of biosynthesized substances (water, acid, buffers, and enzymes) into lumen of GI tract.
cori cycle
The removal and recycling of lactate by the liver, Liver converts lactiate to pyruvic acid, Glucose is released to recharge muscle glycogen reserves (a gluconeogenic process)
gastrointestinal tract
The stomach and intestine as a functional unit. (aka alimentary canal)
Premolars
The teeth immediately behind the canines; first and second; used in chewing, grinding, and shearing food. "bicuspids"
anal (rectal) sphincter
The valve that controls the release of feces from the recturm. It has an internal part made of smooth muscle (thus involuntary) and an external part made of skeletal muscle (thus voluntary).
Canines
These teeth are used are for ripping or piercing. "cuspids," "eyeteeth"
Ileum
Third part of the small intestine. It connects to the cecum of the large intestine. Some digestion takes place there. There is absorption of nutrients and water through its wall into the blood; about 12 feet in length
cytochrome oxidase complex
Third protein complex in ETC. This complex uses 4 electrons to reduce a molecule of oxygen with 2 protons to form water. O2+(4H+)+(4e-)=2H2O
teniae coli, haustra, epiploic (omental) appendages
Three unique anatomical features of the large intestine
3-6 days
Time period in which mucosal surface of the mucosal barrier of the stomach is renewed
True
True or False. Some amino acids can circumvent being converted into Acetyl CoA and directly enter the Kreb's cycle with minimal modification.
False
True or False. The body can store essential amino acids
Thick epithelium
Type of covering in the oral cavity that helps to withstand the friction of chewing
anaerobic
Type of glycolysis that occurs in the absence f O2, and is used during short duration activity.
aerobic
Type of glycolysis that occurs in the presence of O2, and is needed for long duration activity
crown
Visible part of the tooth
complex b vitamins, vitamin k
Vitamins synthesized by bacterial action in the colon.
D, K, A
Vitamins that can be synthesized in the body
facilitated diffusion
What allows glucose to pass through the plasma membrane to be used by the cell?
insulin
What hormone acts by increasing the insertion of GluT4 transporters into the plasma membrane increasing the rate of facilitate diffusion of glucose into the cell?
2 ATP, 6 NADH, 2 FADH2, 4 CO2
What is generated and produced from the Krebs Cycle?
produce energy, cytoplasm
What is purpose of glycolysis? Where does it occur?
45-65%
What percent of your diet per day should be carbohydrates?
30%
What percent of your diet per day should be fat?
water, electrolytes, some vitamins
What substances does the large intestine absorb?
acetyl coenzyme a
When oxygen is present, pyruvic acid is transported to the mitochondrion, where each pyruvic acid is converted into WHAT?
liver (mostly), kidneys (sometimes)
Where does gluconeogenesis occur?
matrix of the mitochondria
Where does pyruvate oxidation occur?
matrix of the mitochondria
Where does the Krebs cycle take place?
inner membrane of mitochondria (series of electron carriers)
Where does the electron transport chain take place?
VLDL, 2-30 mg/dL
Which lipoprotien is the "bad" cholesterol that transports triglycerides from the liver to adipose tissue? What is the ideal level for this lipoprotein?
ATP
Which of the following contains a high-energy bond? ATP, ADP, AMP
LDL, less than 190 mg/dL
Which of the lipoproteins is the "bad" lipoprotein that delivers most cholesterol in blood and delivers it to cells? What is the ideal level of this lipoprotein?
1 kcal, 1kg, H2O, 1 degree C
_________ equals the amount of energy needed to raise the temperature of __________ of ___________ by __________
bile
a bitter greenish-brown alkaline fluid that aids digestion and is secreted by the liver and stored in the gallbladder; important in the emulsification of fats
vegetarian diet
a diet in which vegetables are the foundation and meat, fish, and poultry are restricted or eliminated
mesentery
a double layer of peritoneum that attaches to the back wall of the abdominal cavity and supports the small intestines; route for blood vessels, lymphatics, and nerves
lingual lipase
a fat-splitting enzyme secreted by cells at the base of the tongue
mucin
a glycoprotein constituent of mucus
lacteal
a lymph tubule located in the villus that absorbs fatty acids
tongue
a mobile mass of muscular tissue covered with mucous membrane and located in the oral cavity
peritoneum
a multilayered membrane that protects and holds the organs in place within the abdominal cavity
vegan diet
a plant-based diet that eliminates all animal products
alpha-linolenic acid (omega-3 fatty acid)
a polyunsaturated essential fatty acid found in fish, shellfish, some nuts, and flaxseed
submandibular gland
a salivary gland inside the lower jaw on either side that produces most of the nocturnal saliva
pectin
a soluble gelatinous polysaccharide that is present in ripe fruits and is extracted for use as a setting agent in jams and jellies; soluble in the digestive system, and keeps some water in intestinal contents.
dental plaque
a sticky biofilm of debris, sugar, and bacteria accumulating on the teeth that is formed by and harbors bacteria; also called tartar; causes leaches calcium salts from teeth
contractile proteins
actin and myosin; generate force during contraction
AMP
adenosine monophosphate
9.3 L
amount of water ingested and secreted per day (average)
9.2 L
amount of water reabsorbed mostly from small intestine (some from large intestine)
sigmoid colon
an S-shaped structure that continues from the descending colon above and joins with the rectum below
carbonic anhydrase
an enzyme that catalyzes the interconversion of dissolved bicarbonates and carbon dioxide; important in formation of HCl in stomach acids
arachidonic acid
an omega-6 polyunsaturated fatty acid with 20 carbons and four double bonds; present in small amounts in meat and other animal products and synthesized in the body from linoleic acid.
bilirubin
an orange-yellow pigment formed in the liver by the breakdown of hemoglobin and excreted in bile (colors feces)
oral orifice
anterior opening of the mouth
4 hours
approximate length of time it takes to completely empty stomach after normal meal
fat soluble vitamins
are absorbed by fat, include vitamins A, D, E, K
periodontal ligament
attaches tooth to jaw, thus holding it in the socket
Dental caries
bacterial enzymes ferment CHO deposits on plaque, enzymes produce acids that demineralize surface
animal products
best source of complete proteins
muscularis externa
bilayer of smooth muscle which consists of a layer running circularly and another running longitudinally
functions of liver
bile production, storage, nutrient interconversion, detoxification, phagocytosis, synthesis, vitamin D activation
High-density lipoprotein (HDL)
blood fat that helps transport cholesterol out of the arteries, thereby protecting against heart disease
low-density lipoprotein (LDL)
blood fat that transports cholesterol to organs and tissues; excess amounts result in the accumulation of fatty deposits on artery walls
immunoproteins
blood proteins such as antibodies that play a role in the functioning of the immune system (antibodies)
hard palate
bony anterior (front) portion of the palate
catabolic reactions (decomposition)
break down large chemicals and release energy
Lipolysis (lipid catabolism)
breakdown of fat from triglycerides into fatty acids and glycerol
Glycogenolysis
breakdown of glycogen to glucose
glycogenolysis
breakdown of glycogen to glucose (catabolic process)
lactose
carbohydrate found in milk
types of nutrients
carbohydrates, fats, proteins, vitamins, minerals, water
hydrolases
catalyze cleavage with the addition of water
oxidoreductases
catalyze oxidation-reduction reactions that involve the transfer of electrons
ligases
catalyze the formation of bonds with the input of ATP and the removal of water
isomerase
catalyzes the rearrangement of bonds within a single molecule
incisors
central and lateral teeth between the canines that are used for cutting and nipping; erupt 1st.
hormones
chemical messengers that are manufactured by the endocrine glands, travel through the bloodstream, and affect other tissues
bile salts
cholesterol derivatives that function in fat emulsification and absorption
mixing and propulsion
churning and movement of food through GI tract
lipoproteins
clusters of lipids associated with proteins that serve as transport vehicles for lipids in the lymph and blood
flavin adenine dinucleotide (FAD)
coenzyme that shuttles protons and electrons from glycolysis and the Krebs cycle to the electron transport chain
hepatic portal vein, bile duct, hepatic artery
components of a portal triad
bile salts, bilirubin
components of bile
water, electrolytes, salivary amylase, lingual lipase, lysozyme, IgA, Mucin
components of saliva
vitamins
compounds that help regulate many vital body processes, including the digestion, absorption, and metabolism of other nutrients
lesser curvature
concave medial surface of the stomach
VLDL, LDL
considered "bad" cholesterol because they carry cholesterol to peripheral cells >can contribute to disease due to build up of plaque in arteries
feces
consist of water, inorganic salts, sloughed-off epithelial cells, bacteria, products of bacterial decomposition, and undigested portions of food
pulp cavity
contains blood vessels and nerves of the tooth
actin, myosin
contractile proteins
autonomic nervous system
controls glands and muscles of the digestive system (stimulate--sympathetic; suppress--parasympathetic)
Fructose, galactose
converted to glucose in the liver
greater curvature
convex lateral surface of the stomach
microvilli
create the "brush border" of the mucosa's absorptive cells (enterocytes); formed by extensions of the enterocyte's cytoplasm
circular folds
deep folds of the mucosa and submucosa that extend completely or partially around the circumference of the small intestine
eggs, dairy, organ meats
dietary sources of cholesterol
amino acids
digested proteins are broken down into ___________ ___________.
amylase, protease, lipase, nuclease
digestive enzymes produced by the pancreas
gastric juice
digestive secretions of the stomach glands consisting chiefly of hydrochloric acid and mucin and the enzymes pepsin and rennin and lipase
central vein
drains blood from sinusoids and out of liver
defecation
elimination of feces from the digestive tract through the anus (elimination only)
post absorptive state
energy needs are met by fuels already in the body; break down stored energy sources via glycogenolysis, lipolysis, protein catabolism, and gluconeogenesis
hepatic sinusoids
enlarged, leaky capillaries located between hepatic plates that allow blood to percolate from triads to central vein
lipases
enzymes that break down lipids
proteases
enzymes that continue the breakdown of polypeptides in the small intestine
gastric ulcers
erosion of the gastric mucosa
enteric pacemaker cells
establish the stomach's basic electrical rhythm of peristaltic waves; generate subthreshold depolarization waves
flavin mononucleotide, cytochromes, iron-sulfur centers, copper atoms, coenzyme Q
examples of electron carriers
ketoacidosis
excessive production of ketones, making the blood acidic
essential fatty acids
fats needed by the body that must be consumed in the diet because the human body cannot manufacture them
omentum
fatty sheet extension of the peritoneum attached to the stomach and connecting it with other abdominal organs
collagen, elastin, keratin
fibrous proteins
duodenum
first portion of the small intestine distal to the stomach
Gluconeogenesis
formation of glucose from noncarbohydrate sources
glycogenesis
formation of glycogen from glucose
glycogenesis
formation of glycogen from glucose (anabolic process)
Linoleic acid (omega-6 fatty acid)
found in vegetable and nut oils, and forms arachidonic acid
triglycerides
fuel skeletal muscle and hepatocytes
lobules
functional units of the liver; hexagonal in shape with hepatocyte plates radiating out
pharynx
funnel shaped tube that extends from the internal nares to the esophogas
reduction
gain of electrons
fasting
going without food for a period of time; typically a few hours to a few days
starvation
going without food or inadequate food intake for weeks or months
teeth
hard bony projections in the jaws for masticating (chewing) food
enamel
hard, outermost layer of a tooth
IgA
immunoglobulin A
proton pumps
important transport proteins that use energy from ATP to pump protons from the inner mitochondrial space to the outer mitochondrial space
water soluble vitamins
includes Vitamin C, Vitamin B-Complex
splanchnic circulation
includes those arteries that branch off the abdominal aorta to serve the digestive organs and the hepatic portal circulation
gingivitis
inflammation of gums as tartar disrupts seal between gingivae and teeth
Absorptive state
ingested nutrients are entering the bloodstream, and glucose is readily available for ATP production
gastric accommodation
intrinsic ability of smooth muscle to exhibit stress-relaxation response, which enables hollow organs to stretch without increasing tension or contractions
Polysaccharides
large macromolecules formed from monosaccharides (10+)
liver
largest gland in the body
1.5 m
length of large intestine
parotid salivary gland
lies under the skin covering the lateral and posterior surface of the mandible
very low density lipoproteins
lipoproteins that transport triglycerides and other lipids from the liver to various tissues in the body (adipose tissue)
hepatocytes
liver cells; produce bile, absorb and secrete nutrients like glucose, and secrete plasma proteins
segmentation
local constriction of the small intestine that mixes food with digestive juices
Ribosomes
location of protein synthesis
hepatocytes
location of synthesis of cholesterol
oxidation
loss of electrons
100,000 times
magnitude of acidity of gastric juices compared to blood
ATP (adenosine triphosphate)
main energy source that cells use for most of their work; composed of a sugar ribose, nitrogenous base adenine, and a chain of three phosphate groups bonded to it.
fluid balance
maintenance of the proper types and amounts of fluid in each compartment of the body fluids
maltose
malt sugar; glucose + glucose
digestion
mechanical and chemical breakdown of food
mucous membrane (mucosa)
membrane that forms the linings of body cavities open to the exterior (digestive, respiratory, urinary, and reproductive tracts)
Jejunum
middle portion of small intestine where chemical digestion ends and absorption begins; about 8 feet in length
lactose
milk sugar; glucose + galactose
Calcium, phosphorus, potassium, sulfur, sodium, chlorine, magnesium
moderate amounts of these minerals are required in diet for body functions
GluT
molecule that transports glucose via facilitated diffusion in the cell membrane
simple carbohydrates
monosaccharides and disaccharides; found in sugars in fruits, honey, sugar beets, milk, & sugar cane
triglycerides
most abundant dietary fats
plants
most dietary carbohydrates come from what source?
haustral churning
movement of the chyme back and forth within the haustra in the large intestine, results in onward movement of contents
bicarbonate (HCO3)
mucus of stomach lining rich in this compound
pyloric canal
muscle that connects the stomach to the proximal duodenum
soft palate
muscular posterior (back) portion of the palate
myenteric plexus
nerve supply between the two layers of the muscularis externa; provides smooth, coordinated contraction for peristalsis
30-32 ATP, 6 CO2, 6 H2O
net products of all steps of cellular respiration from one molecule of glucose (excluding coenzymes)
submucosal plexus
neuronal network in submucosa that controls secretions of esophageal, stomach, and intestinal walls
2 ATP
number of ATP needed to facilitate glycolysis
4
number of complexes which remove electrons from coenzymes (NADH, FADH2)
20
number of deciduous teeth
4
number of lobes of the liver
32
number of permanent teeth
fermentation
occurs in the large intestine, and substances are further broken down by bacteria
complex carbohydrates
oligosaccharides and polysaccharides; found in grains, potatoes, and vegetables
liver, intestines
organs that produce lipoproteins
root (tooth)
part of the tooth below the gum line
small intestine, lymphatic vessel, hepatic portal vein, liver, vena cava, heart, systemic circulation
pathway of nutrients
25%
percent of cardiac output that infuses splanchnic circulation
peridontitis
periodontal ligament and bone are attacked by immune cells
cellulose
polysaccharide consisting of glucose monomers that reinforces plant-cell walls; insoluble in the digestive system
colon
portion of the large intestine consisting of the ascending, transverse, descending, and sigmoid segments
haustra
pouches that form in the large intestine when the longitudinal muscles are shorter than the colon
1.5
pressure remains constant in stomach for the first __________ liters added to it
Lipogenesis
process of synthesizing lipids from glucose or amino acids; occurs when individuals consume more calories than needed; stored mostly as triacylgycerols
mucous neck cells
produce thin, acidic mucus to lubricate the food entering the stomach
2 CO2, 2 NADH, 2 acetyl CoA
products of pyruvate oxidation
mucosal barrier
protective barrier that prevents gastric juice from destroying the stomach itself
Electron carriers
proteins arranged in chains on the membrane to allow the transfer of electrons from one carrier to another.
enzymes
proteins that act as biological catalysts
adipose tissue
provides protective padding, insulation, and support
receptive relaxation
reflex-mediated relaxation of smooth muscle coordinated by swallowing center of brain stem
anal canal
region, containing two sphincters, through which feces are expelled from the body
lipid metabolism
regulates circulating levels of triglycerides, fatty acids, and cholesterol
neurons, RBCs
rely almost entirely upon glucose to supply their energy needs
neurons, red blood cells
rely exclusivly on glucose to meet their energy needs
negative nitrogen balance
results from excessive protein breakdown; ex. physical/emotional stress, starvation
pyloric sphincter
ring of muscle that guards the opening between the stomach and the duodenum
papillae
rough, bumpy elevations on dorsal surface of tongue, some of which contain taste buds.
fundus (stomach)
rounded upper portion of the stomach
sublingual gland
salivary gland under the tongue
parietal cells
secrete HCl and intrinsic factor
enteroendocrine cells
secrete hormones and paracrine messengers that regulate digestion
chief cells
secrete pepsinogen and lipases
Oligosaccharides
short chains of 3-10 monosaccharides
bile canaliculi
small ducts between hepatocytes that collect bile
epiloic (omental) appendages
small, fat filled pouches of visceral periotneum that hang from the surface of the large intestine
peritoneal cavity
space between the parietal and visceral peritoneum; contains serous fluid
anabolic reactions (synthesis)
synthesis of larger molecules from smaller ones
sucrose
table sugar; glucose + fructose
deglutition
the act of swallowing
Nitrogen balance
the amount of nitrogen consumed compared with the amount excreted in a given time period
oropharynx
the area directly posterior to the mouth
cellular respiration (aerobic respiration)
the breakdown of organic molecules within the cell when oxygen is present
cecum
the cavity in which the large intestine begins and into which the ileum opens
oral cavity (buccal cavity)
the cavity within the mouth
Chylomicrons
the class of lipoproteins that transport lipids from the intestinal cells to the rest of the body, especially adipose tissue
metabolism
the combination of chemical reactions through which an organism builds up or breaks down materials
pylorus
the distal narrow passage that connects the stomach with the small intestine
duodenum
the first part of the small intestine immediately beyond the stomach, leading to the jejunum; approximately 10" in length
rugae
the folds in the mucosa lining the stomach
glucose
the form of sugar that circulates in the blood and provides the major source of energy for body tissues. When its level is low, we feel hunger. Used by cells to produce ATP.
visceral peritoneum
the inner layer of the peritoneum that surrounds the organs of the abdominal cavity
pharynx
the membrane-lined cavity behind the nose and mouth, connecting them to the esophagus.
transverse colon
the middle part of the large intestine, passing across the abdomen from right to left below the stomach.
parietal peritoneum
the outer layer of the peritoneum that lines the interior of the abdominal wall
anaerobic glycolysis
the overall process where pyruvic acid generated durring glycolysis is converted to lactic acid
mastication
the process of chewing
peristalsis
the process of wave-like muscle contractions of the alimentary tract that moves food along
ileocecal sphincter
the ring-like muscle that controls the flow from the ileum of the small intestine into the cecum of the large intestine
hepatic vein
the vein that collects blood from the liver and returns it to the heart
alimentary canal
the whole passage along which food passes through the body from mouth to anus. It includes the esophagus, stomach, and intestines.
teniae coli
three bands of longitudinal smooth muscle in muscularis of large intestine
mucosa, submucosa, muscularis externa, serosa
tissue layers of alimentary canal
gingiva
tissue surrounding the teeth and covering the jaw (gums)
10
total number of reactions involved in glycolysis
8
total number of reactions involved in the citric acid (krebs or TCA) cycle?
iron, iodine
trace amounts of these are required in diet for body functions
transferases
transfer functional groups from one substrate to another
fatty acids
transported through small intestinal epithelial cells to lacteals of lymphatic system
amino acids, dipeptides, tripeptides
transported via diffusion to blood capillary from small intestine
glucose, galactose, fructose
transported via facilitated diffusion to blood capillary from small intestine
albumin, lipoproteins
transporter proteins
descending colon
travels down the left side of the abdominal cavity to the sigmoid colon
ascending colon
travels upward from the cecum to the undersurface of the liver
oxidation, phosphorylation
two processes involved in the ilectron transport chain
tight junctions
type of intercellular junction between mucosal cells of the stomach
calculus
unremoved dental plaque that has calcified
exercise, diet, certain drugs
used to reduce high cholesterol levels
nutrition
using nutrients for growth, synthesis, repair and energy
ileocecal valve
valve between the ileum of the small intestine and the cecum of the large intestine
coenzymes
vitamins that assist in the normal functioning of enzymes
Metabolic water
water generated as a result of oxidative phosphorylation
capture energy, ATP
what is the function of the electron transport chain? In what form is this acheived?
positive nitrogen balance
when protein intake and/or synthesis is higher than protein breakdown; ex. after tissue injury, pregnancy, childhood, illness
neck (tooth)
where the crown and root meet
root canal
where the pulp cavity extends into the root; provides a route for blood vessels, nerves, and other pulp structures to enter the pulp cavity of the tooth