Biology Test 3


Mucosa


innermost tissue layer all nutrients must cross it to enter the blood


submucosa


layer of connective tissue containing blood vessels, lymph vessels, and nerves.


muscularis


2 or 3 layers of smooth muscles responsible for mvoement in GI tract


serosa


outermost layer of the GI tract wallconnective tissue that surrounds and protects other layers


Gastrointestinal tract layers


Digestive System Processes
1) Mechanical Processing and Movement


chewing, mixing, and propelling


Digestive System Processes
2) Secretion


fluid, digestive enzymes, hormones, bile, acid, alkali, mucus are secreted into the GI Tract.


Digestive System Processes?
3) Digestion


contents of lumen are broken down into the smallest absorbable units


Digestive System Processes
4) Absorption


through mucosa into blood or lymph vessels


Digestive System Processes
5) Elimination


Undigested material is eliminated form the body


bolus


food chewed into a mass


peristalsis


propels food down the GI tract by wave like muscle contractionsmainly in esophagus


segmentation


mixes food by muscles contracting and relaxingmainly in small intestine


The mouth


begins digestion-teeth- tongue- saliva


swallowing


delivers food to stomachvoluntary phase: tongue pushes bolus of food into pharynxinvoluntary phase: receptors in pharynx stimulated by presence of food


epiglottis


closes opening to trachea


pharynx


common passage way for air, liquid, and foodparticipates in swallowing


esophagus


connects pharynx to stomachmix of smooth and skeletal muscles


hiatal hernia


when the stomach protrudes through the diaphragm


stomach


food storagedigestionregulates food flowdoes not absorb nutrients


chyme


blended food


How long does it take to empty stomach?


2-6 hours


Stomach wall


small intestine


digestion: adds enzymes and bilebreaksdown carbohydrates, protiens and lipids95% of absorption happens here


How long is the small intestine?


about 11 feet


duodenum


area of most digestion


mucosa adaptations to the small intestine


folds covered with villi and microvilli give more surface area


villi of small intestie


contain blood and lacteal capillaries, which take in small water soluble nutrients and lipids, respectivly.


pancreas


secretes digestive enzymes and sodium bicarbonate


liver


produces bile and emulsifies fats


hepatic protal system


carries nutirent rich blood from the digestive tract for processing (in liver)


gallbladder


stores bilesecretions are sent to the duodenum


How long is the large intestine?


5 feet


Large intestine


absorbs some nutrients and watereliminates wasteNO digestion


Colons


feces


indigestible material, bacteria


defecation reflex


due to stretch as feces enter the rectum


diarrhea


often due to bacteria infectiontoo little water is absorbed


constipation


waste remains too long in th large intestine causeing too much water to be absorbed


lactose intolerance


difficulty in digesting lactose in milk productsDoug


diverticulosis


mucosa sacs protrude through layers of the large intestinemay become inflamed or infected


polyps


non cancerous growth from colon mucosaususally removed because they can become cancerous over time, ie. colon cancer


hepatitis


inflammation of the liverMom's friend


gallstones


too much cholesterol in bile


peptic ulcers


open sores in the stomach or small intestine


crohn's disease


inflammatory disorder that damages the intestinal liningLauren


irritable bowel syndrome


abdominal pain, diarrhea, constipationeffects smooth muscle's ability to move feces through colonBecky


anorexia


excessive dieting and exercise leads to lower weight than the idealParis Hilton


bulimia


binge and purgedamage teeth, rupture stomachLindsy Lohan


urinary system


regulates: water levels, nitrogenous and other solute waste


kidneys


principle organ; filters blood to produce urine


renal cortex


outside layer of the kidney


renal medulla


pyramid shaped muscles; inner layer of kidney


renal pelvis


where urin collects after it is formed


ureters


transprot urine to the bladder by peristalsis


urinary bladder


stores urine


how much urine can the bladder hold?


600-1000mL


urethra


carries urine from body; two sphincters


nephrons


funcitonal unit that produces urine1 million per kidney


tubules


filter fluid and reabsorb needed substances


bowman's / glomerular capsule


surrounds a network of capillaries


glomerulus


blood supply of the nephron; contained inside bowman's capsule


glomerular filtration


based on pressure differencefilters water, and small solutes into glomerular capsulefiltrate is formed


tubular reabsorption


returns most of the water and needed solutes back to the blood


tubular secretion proximal tubules


removes other substances form blood back to tubules


Purpose of tubular secretion in proximal tubules


regulation of chemical levels in bodyexcretion of harmful chemicals


what is secreted?


penicillincocainemary janepesticidespreservativesH ionsammonium


dilute urine


excreting excess water when Anti-diuretic hormone is absent and reabsorption of salt without reabsorption of water


concentrated urine


conserving water due to increased anti-diuretic hormone


micturition reflex


as bladder fills, stretching occurs, and sphincters come into play


kidney stones


minerals in urine crystallize in renal pelviscan be surgically removed or crushed with ultrasonic shock waves


Urinary Tract Infection


presence of microbes in urine or an infection in any part of the urinary system


acute and chronic renal failure


conditions that impair kidney functions temporarily


scrotum


sac, regulates temperature of testes


testes


produce sperm and testosterone


penis


conveys urine and spermerectile tissue; functions in sexual intercourse


seminal vesicles


secretes fructose, seminal fluid


prostate gland


secretes watery alkaline fluid; neutralizes acidic vagina


bulbourethral gland


secretes lubricating mucuscleanses urethra


ovaries


release eggssecrete estrogen and progesterone


eggs are also known as...


an oocytes


oviduct is also known as


fallopian tubeuterine tube


fallopian tube


fringed ends to receive eggis not connected to ovary


uterus


the hallow, pear-shaped organ where fertilized egg grows and develops


endometrium


innermost layer of uterussite where fertilized egg implantssloughs off during menstrual flow


myometrium


smooth muscleexpands during pregnancyconstricts during labor


cervix


opening to the uteruspermits sperm to enter the uterusallows the fetus to exit during birth


vagina


organ of sexual intercoursebirth canal


external genitalia


vulva including labia majora and labia minora


clitoris


female erectile tissue


Breasts include


mammary gland100s of milk producing lobules; ducts; adipose tissuelactation


mammary glands


undergo changes due to hormones at puberty, during and after pregnancy


lactation


milk production, estrogen and progesterone influence


How is Sperm made?


in seminiferous tubules it undergoes cell division by mitosis and meosis


Sperm have how many chromosomes


23 (N)half than normal cells


sequence of sperm development


Spermatogonia 2Nprimary spermatocyte 2Nsecondary spermatocyte Nsermatids Nsperm N


sperm


head containing DNAacrosome with enzymes (tip of head)tail with mitochondria


sperm travel


to epididymisto vas (ductus) deferensejaculatory ducturethra


Testosterone


made by interstitial/Leydig cells between seminiferous tubulescontrols growth and function of male reproductive tissuesstimulates aggression, sexual behavior and secondary sexual characteristics


GnRH, LH & FSH hormones


involved in production and secretion of testosterone


Menstrual Cycle


every 28 daysunder hormone controlbegins at puberty


what two cycles are involved with the menstrual cycle


ovarian cycleuterine cycle


how many primary oocytes is a female born with?


about 1 million, which are stored in the ovary


how many eggs are left come time for puberty for a woman?


only 300,000 (most are absorbed)


What happens each month to primary oocytes?


several begin developmentusually only 1 completes this process


Ovarian Cycle


Immature follicle of 1 oocyte develops, FSH and LH increasezona pellucida around oocyteantrum space develops, some estrogen and progesterone secreted2 oocyte and polar body produced, follicle maturesincreased estrogen causes surge of LH, ovulation occurs--> follicle ruptures to realse 2 oocytecorpus luteum formed from follicle