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110 Cards in this Set
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Endocrine glands
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secrete products directly into body fluids (blood, lymph) |
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Exocrine glands |
secrete products into ducts which lead to the surface of a membrane (sweat glands, salivary glands) |
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Amino acid-based hormones |
hormones that use amino acids as the basis of their structure (not lipid soluble) |
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Steroids |
hormones synthesized from cholesterol (lipid soluble - which means they can pass through cell membranes) usually gonadal hormones and adrenocortical hormones
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hormone stimulation usually produces... |
a) opening or closing of ion channels in the cell membrane b) synthesis of proteins within the cell c) enzyme activation or deactivation (often due to phosphorylation of the enzymes) d) induction of secretory activity e) stimulation of mitosis or meiosis |
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Second-messenger |
chemical produced or released as the result of the hormone binding to its receptor on the membrane of the target cell.
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2nd Mess. Ex: cAMP |
cAMP (cyclic adenosine monophosphate) hormone binds to receptor -> activates G-proteins -> activates adenylate cyclites => produces cAMP (the 2nd mess.) -> activates protein kinases --> phosphorylates other enzymes -> causes intracellular change |
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2nd Mess. Ex: Ca+2 |
Ca+2 (calcium ions) can work alone part of calcium-calmodulin (smooth muscle contraction process) |
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Amplification |
large intracellular changes caused by small amounts of hormone (usually due to second messenger making changes occur) |
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Onset of hormones |
peptide hormones usually cause an immediate reaction because the receptor (that the second mess. binds to) is in easy access outside of the cell. steroid hormones may take hours to days to have an effect. they must go through the cell membrane by process of diffusion. |
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Negative feedback systems |
system designed to closely regulate the hormones of your body. the response of the hormone causes the body to react oppositely to the stimulus that caused the hormone release. organ 1 -> produces hormone 1 => causes organ 2 -> to produce hormone 2 => causes organ 3 -> to produce hormone 3 => which affects the target organ |
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Anterior (frontal) pituitary
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secretes six major hormones: growth hormone, prolactin, thyroid-stimulating hormone, adrenocorticotropic hormone, follicle-stimulating hormone, luteinizing hormone. all are peptides/proteins and last 4 are tropic hormones. tissue is mainly composed of glandular epithelium. |
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Growth hormone (GH) |
stimulates body cells to increase in size, accelerates the rate of mitosis.
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Hyposecretion (of growth hormone) |
causes dwarfism in children, typically nothing in adults.
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Hypersecretion (of GH) |
causes gigantism (giantism) as a child, and acromegaly as an adult.
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Thyroid-stimulating hormone (TSH) |
controls the secretion of hormones produced by the thyroid gland (calcitonin, thyroxine, and triiodothyronine)
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Adrenocorticotropic hormone (ACTH) |
controls the secretion of hormones produced by the adrenal cortex (aldosterone, cortisol, and androgens)
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Follicle-stimulating hormone (FSH)
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in females, stimulates the growth and development of egg-containing follicles in the ovary. in males, stimulates the maturation of sperm. |
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Luteinizing hormone (LH) |
in both sexes, promotes the secretion of sex hormones. in females, causes expulsion of egg from the ovaries, allowing fertilization to occur during ovulation. |
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Prolactin (PRL) |
in females, promotes breast development and stimulates milk production. in males, increases testes sensitivity to LH |
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Posterior (back) pituitary |
releases two hormones (that are produced by the hypothalamus): oxytocin and antidiuretic hormone. |
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Oxytocin (OT) |
causes the muscles of the uterine wall to contract, increases contractions during labor.
causes let-down and release of breast milk. |
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Antidiuretic hormone (ADH) |
reduces urine production. |
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Diabetes insipidus ("tasteless overflow") |
excess urine is produced due to insufficient ADH production and release. |
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Thyroid gland |
located in the neck. has two lobules which are subdivided into colloid-filled follicles. |
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Thyroxine and triiodothyronine (T3 and T4) |
two hormones stimulated by the thyroid gland. increases metabolism rate, enhances protein synthesis, and stimulates lipid breakdown. both hormones contain iodine. goiters can occur due to iodine deficiency. |
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Hypothyroidism |
known as cretinism in children, and myxedema in adults. can cause short stature, low body temperature, lethargy, weight gain, thick tongue and neck, and mental retardation.
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Hyperthyroidism |
known as Grave's disease (most commonly) causes elevated metabolism rate, sweating, weight loss, nervousness, rapid/irregular heartbeat, and often exophthalmos (bulging eyeballs) |
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Calcitonin |
the other hormone produced by the thyroid gland. lowers blood calcium and phosphate levels by promoting their storage in bone. |
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Parathyroid gland |
located on the posterior surface of the thyroid glands. stimulates the release of parathyroid hormone (PTH). functions to raise blood calcium levels, and stimulates osteoclasts to resorb the bone matrix, as well as causes kidneys to conserve calcium and excrete phosphate. stimulates the conversion of Vitamin D into its active form, which causes an increase in calcium absorption. |
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Calcium levels in the bloodstream are maintained for... |
a) muscle contraction b) transmission of neural impulses c) blood clotting d) enzyme activity |
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Adrenal glands (suprarenal glands) |
located on the top of the kidneys in humans. divided into two major sections: adrenal medulla and adrenal cortex. releases cortisol, aldosterone, and androgen. |
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Adrenal cortex |
outer portion of the adrenal gland, mainly glandular epithelium. produces corticosteroids (synthesized from cholesterol) as over two dozen hormones, subdivided into three groups. |
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Mineralocorticoids |
steroid hormones whose main function is the regulation of electrolyte concentrations in extracellular fluids (mostly blood and lymph) produced as aldosterone |
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Glucocorticoids |
steroid hormones whose main function is to help maintain blood sugar levels and blood volume. helps provide resistance to stressors and controls the metabolism rate of most cells. produced as cortisol |
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Gonadocorticoids |
steroid hormones whose main function is stimulating the sex organs, onset of puberty, and other functions related to reproduction. produced as androgens |
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Aldosterone |
most potent mineralocorticoid, comprises 95% of mineralocorticoids produced. helps maintain blood volume and blood pressure. causes kidneys to conserve sodium and water and to excrete potassium. its release can be caused by high potassium levels, hyponatremia (too little sodium in the blood), decreasing blood pressure, and decreasing blood volume. |
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Atrial natriuretic factor |
inhibits renin and aldosterone secretion. causes a rapid decrease in blood pressure. |
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Cortisol |
the major glucocorticoid. produced in response to long term stress to increase glucose levels in the blood. inhibits the synthesis of proteins and promotes the release of fatty acids. stimulates gluconeogenesis. |
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Hypersecretion (of cortisol) |
Cushing's disease symptoms: hyperglycemia, loss of muscle and bone protein, hypertension, edema (excess fluid in tissues) |
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Addison's disease
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caused by insufficient production of glucocorticoids and mineralocorticoids.
symptoms: causes bronzing of skin, hypotension, low glucose and sodium, and weight loss. |
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Androgens |
major group of gonadocorticoids. dehydroepiandrosterone is the main androgen produced by the adrenal cortex. these help supplement the sex hormones produced by the gonads. can be converted into testosterone and estrogen by the peripheral tissues. stimulates libido, growth of pubic and axillary hair, and onset of puberty in both males and females. |
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Adrenogenital syndrome |
Cushing's disease that additionally has a hypersecretion of androgens. (people born with this often have both sets of genitals, physically speaking) |
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Epinephrine and norepinephrine |
adrenalin and noradrenalin produce similar effects as seen with SANS activation. |
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Pancreas |
located just posterior and inferior to the stomach, attached to the small intestine. has both exocrine and endocrine gland cells. islets of Langerhans (details on specific card) |
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Islets of Langerhans |
endocrine portion of the pancreas alpha cells = secrete glucagon beta cells = secrete insulin delta cells = secrete pancreatic somatostatin |
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Glucagon |
increases blood glucose levels when they get low. stimulates gluconeogenesis in the liver, promotes breakdown of glycogen, and causes glucose release by the liver. |
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Insulin |
decreases blood glucose levels when they get high (does the opposite as glucagon) promotes movement of glucose through the cell membrane, stimulates storage of glucose and fat, stimulates glycogen and protein synthesis. nerve cells lack insulin receptors and must rely on diffusion. |
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Diabetes mellitus ("honey overflow") |
excess glucose causes an excessive production of urine with glucose in it. Type I = "Juvenile onset" = insulin dependent diabetes mellitus insulin is insufficiently produced, insulin shots/insulin pumps are used to treat it. Type II = "Adult onset" = noninsulin dependent diabetes mellitus body stops responding to insulin. insulin is produced but doesn't affect the cells of the body. (can become irreversible, insulin will stop being made. insulin shots can help then) |
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The ovaries |
secretes estrogen and progesterone. regulate menstruation, regulates maturation of the female sexual organs (menopause can cause regression of sex organs) produces female secondary sexual characteristics (breasts, adipose on hips and thighs) |
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The testes |
produces testosterone, regulates maturation of male sex hormones. produce male secondary sexual characteristics (hair, muscle build) |
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Pineal gland |
attached to the thalamus near the third ventricle. innervation comes from the postganglionic nerve fibers. secretes melatonin (supposed to help you sleep) may help control circadian rhythm. inhibits gonadotropin secretion in children (helps regulate the onset of puberty) |
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Melatonin |
supposed to help you sleep, helps control circadian rhythm, and inhibits gonadotropin, secretion in children. melatonin secretion varies with the time of day, more is secreted at night (discourages humans from being nocturnal) reduced melatonin may cause more gonadotropins, which can start puberty earlier and mess up the menstrual cycle. |
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Thymus gland |
located in the area between the lungs, just anterior to the heart. size diminishes with age. produces thymosin, a hormone that induces the maturation of T lymphocytes (T-cells). people didn't move around until 100 yrs ago ish and now that they do, we may evolve to make t-cells for a longer period of time. |
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Other endocrine structures... |
Heart secretes atrial natriuretic factor (ANF) in response to a rapid rise in high blood pressure. Gastrointestinal tract mucosa secretes several hormones (discussed more in digestive system section) Placenta secretes several steroid and protein hormones during pregnancy. allows baby and mother to grow. Kidney secretes erythropoietin. causes red blood cell production. Skin produces cholecalciferol = inactive Vitamin D. modified by the liver, activated by the kidneys, and causes an increase in calcium absorption in the small intestine. |
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Digestion |
process of changing food substances into smaller compounds which can be absorbed by the body. |
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Digestive system |
the organs of the alimentary canal as well as several accessory organs. |
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Layers of the alimentary canal |
Mucous membrane secretion (of mucus enzymes, and hormones), absorption, and protection. Submucosa provides nutrients for the other layers via blood vessels. dense irregular connective tissue with blood vessels. Muscular layer mixes and moves the contents. circular layer and longitudinal layer. Serous layer lubricates the digestive organs (externally), and thus protects them from damage due to friction. |
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Peristalsis |
alternating waves of contraction and relaxation that propel the contents of the digestive system forward. (similar to squeezing a toothpaste bottle) major means of propulsion in the alimentary canal. |
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Parasympathetic impulses in the alimentary canal... |
generally cause an increase in digestive activities
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Sympathetic impulses in the alimentary canal... |
generally inhibits digestive activities, also causes contraction of the sphincter muscles that control the movements of the contents through the various regions of the alimentary canal. depression may cause you to feel more full because of this. |
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Mouth (oral cavity, opening to the alimentary canal) |
opens to the outside of the body to accommodate feeding, helps prepare food for digestion, serves as an organ of speech and pleasure. |
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Cheeks |
form the lateral walls of the oral cavity |
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Lips |
boundary between the skin of the face and the mucous membranes lining the alimentary canal. highly mobile, and able to judge the temperature and texture of food. |
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Tongue |
thick, muscular organ on the inferior side of the oral cavity. functions: aids in the mixing of food with saliva, pushes food into and away from the teeth, pushes food towards the pharynx for swallowing. |
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Papillae |
small bumps on the surface of the tongue. contains tastebuds and makes the tongue rough, allowing for better food manipulation. |
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Palate |
Hard palate anterior, bone-lined part towards the front. Soft palate posterior, softer tissue-lined part towards the back. during swallowing, the uvula and soft palate close off the opening between the nasal cavity and the oropharynx. |
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Teeth |
Primary teeth (deciduous teeth) - 20 teeth that are replaced and grow in from around 6 months to 3 years of age. Secondary teeth (permanent teeth) - 32 teeth used for rest of life and grow in from around 6 years to 30 years of age. |
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Types of teeth |
Incisors (8) for biting Cuspids (4) for grasping and tearing Bicuspids (8) for grinding and crushing Molars (12) for grinding |
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Mastication |
Chewing (increases the surface area of food, more nutrients gleaned) |
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Parts of the tooth |
Root area below the gingival (the gums) Crown area above the gingiva Dentin substance similar to bone, forming most of the tooth Pulp cavity hollow interior Root canal blood vessels, nerves, and connective tissue Enamel substance covering the crown of the tooth, hardest substance in the body. contains calcium salts. |
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Gingiva |
gums |
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Dental caries |
oral cavities, tooth decay, decalcification of tooth enamel, followed by the destruction of the enamel and dentin. can be caused by lack of dental cleanliness and diet with a high sugar content. dental caries form when bacteria colonize teeth and then produce acids, which dissolves the calcified salts. |
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Salivary glands |
secrete saliva (moistens food, binds pieces of food together, begins carbohydrate digestion, makes taste possible, regulates pH in mouth and cleanses food. |
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The parotid glands |
largest of the salivary glands, located anterior to the ear, has only serous cells, produces a saliva rich in amylase. (enzyme that converts starch/glycogen into disaccharides) |
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The submandibular glands |
Located on the floor of the mouth, inside the lower jaw. has some mucous cells and some serous cells. produces a watery saliva, more viscous than the saliva from the parotid glands. |
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The sublingual glands |
smallest of the major salivary glands. located in the floor of the mouth under the tongue. has many mucous cells, produces a thick, stringy saliva. contains lingual lipase which when acidified in the stomach, breaks down triglycerides. |
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Lingual lipase |
compound that is activated as a digestive acid when in the stomach, doesn't do anything in the mouth when contained in saliva. |
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Pharynx |
both mainly function as passageways three parts of the pharynx: nasopharynx, oropharynx, laryngopharynx. all have muscles that use peristalsis |
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Deglutition |
swallowing |
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Bolus |
chewed food mixed with saliva |
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Esophagus |
tube that connects the pharynx to the stomach. esophageal hiatus is the opening in the diaphragm for the esophagus. |
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Hiatal hernia |
tear in the diaphragm at the esophageal hiatus, can be caused by overeating |
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Cardiac sphincter |
circular set of muscle fibers at the gastroesophageal junction (weakest set of muscles in the body) |
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Heartburn |
gastric acid from the stomach goes into the esophagus and causes tissue damage, can be due to a weak cardiac sphincter. |
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Stomach
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muscular, pouchlike organ mixes bolus with gastric juices to form chyme absorbs a few nutrients, moves the chyme into the small intestine. |
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Regions of the stomach |
Cardiac area adjacent to the esophageal opening Fundic superior section of the stomach Body main part of the stomach (largest section) Pyloric muscular section that pushes stomach contents into the small intestine. (pyloric sphincter circular set of muscle fibers which control the movement of the contents of the stomach into the small intestine.) |
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Chyme |
food + gastric juice + saliva = chyme |
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Gastric juice |
secreted by the gastric glands in the stomach (found in the mucosa layer) pepsin enzyme that splits proteins. produced as pepsinogen by chief cells. hydrochloric acid makes the stomach acidic (less acidic than coffee) changes pepsinogen to pepsin. secreted by parietal cells. intrinsic factor aids in the absorption of vitamin B12, also secreted by the parietal cells. the stomach also produces a mucus to protect from stomach ulcers. |
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Gastrin |
peptide hormone that increases gastric gland secretions stimulated by parasympathetic impulses. |
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The three stages of gastric secretion... |
Cephalic secretion secretion occurs prior to food entering the stomach (causes 30-50% of gastric secretions. due to parasympathetic impulses through the vagus nerves (just thinking about or smelling food) Gastric phase secretion occurs due to the presence of food chemicals, pH changes, and stomach distension. (causes 40-50% of gastric secretions) Intestinal phase secretion occurs in response to intestinal gastrin (causes 5% of gastric secretions) caused by gastrin release which occurs when the stomach contents first enter the small intestine. |
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Enterogastric reflex |
inhibition of gastric activities when stomach contents enter the small intestine. acid causes sympathetic reflex impulses, proteins and fats cause cholecystokinin (CKK) secretion, which causes decrease in gastric motility. Fats cause enterogastrone secretion, this decreases gastric secretions. |
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Gastric absorption |
only a few substances are absorbed in the stomach: water, glucose, alcohol, some salts, and lipid-soluble drugs. |
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Rate of digestion |
Liquids >> Carbohydrates >> Proteins >> Fats slowest fastest |
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Emesis |
Vomiting (usually triggered by distension or irritation) controlled by medulla oblongata, can be stimulated by sights, odors, tastes, and emotional feelings. |
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Nausea |
feelings resulting from vomiting center activity. stomach stops, contents go from the small intestine to the stomach. |
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Pancreatic juice |
produced by the acinar cells (the exocrine cells of the pancreas) contains enzymes that breakdown carbohydrates, fats, proteins, and nucleic acids. bicarbonate ions neutralize chyme from the stomach (makes ulcers less likely) |
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Secretin |
peptide hormone released by the duodenal mucosa in response to the acid in chyme protects the stomach from acids. in return, the pancreas secretes a pancreatic juice that has a high concentration of bicarbonate ions. |
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Cholecystokinin (CKK) |
hormone released from the intestinal mucosa in response to the presence of fats and proteins in the chyme. the pancreas, in return, secretes a pancreatic juice that has a high concentration of digestive enzymes. |
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Liver |
largest gland of the body. highly vascularized, enclosed in a hard shell, divided into lobes which are subdivided into lobules. lobules and the functional unit of the liver. functions: regulates glucose concentrations in the blood, controls the synthesis and catabolism of fats and proteins, filters damaged RBC's and bacteria from the blood, stores glycogen, iron, vitamins A, D, and B12, detoxifies many xenobiotics (alcohol and meds) and aids in digestion by producing bile. |
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Hepatic lobule |
functional unit of the liver, carries out the functions of the liver |
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Bile |
yellowish-green liquid continually secreted by the lobules. carried by duct canals --> hepatic ducts --> common bile duct --> to {gall bladder} or {duodenum} composed of bile salts (aids in digestion), bile pigments (breakdown product of RBC's), cholesterol, and electrolytes |
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Gallbladder |
pear-shaped sac located in a depression on the posterior, inferior surface of the liver. stores and concentrates bile. gall stones are calcified crystals of cholesterol that obstruct bile flow. common in women over 40 with high cholesterol, as menopause stops womens use of cholesterol. |
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Functions of bile salts |
emulsifies fats, aids in the absorption of fatty acids, cholesterol, and Vitamin A and E. Bile salts are reabsorbed in the small intestine. |
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Small intestine |
(18-20 ft section of the alimentary canal) completes the digestion of nutrients, absorbs the products, transports remaining residue to the large intestine. duodenum (~10 inches) jejunum (~8 ft) illeum (~12 ft) |
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modifications for absorption |
villi, microvilli, and plicae circulares |
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Segmentation |
major mixing movements, contracts on opposite sides to slosh contents around |
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Peristaltic rush |
quick movement of chyme through the small intestine and into the large intestine, which usually results in diarrhea frequent and watery stools |
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Large intestine |
does not have villi, does have longitudinal muscle. parts: cecum dilated pouch-like structure colon main part of the large intestine rectum storage are for feces anal canal last 1-2 inches of the large intestine anus opening of the anal canal |
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Feces |
odor is caused by products produced by bacteria. constipation is dry feces, can be due to emotional trauma, lack of fiber, ignoring the urge to defecate, and lack of exercise. can become carcinogenic if left in your system. |