Exam 3 Respiratory Flashcards
Respiratory tract
carries air to and from lungs from gas exchange. 2 divisions of respiratory tract
Conducting portion
nasal cavity to larger bronchioles.
Respiratory portion
alveoli. gas exchange occurs in respiratory portion, lower respiratory tract. smallest bronchioles to alveoli.
Upper respiratory tract
filters, warms, and humidifies incoming air. protects delicate lower tract. reabsorbs heat and water in outgoing air
Lower RT
conducts air to and from gas exchange surfaces
Respiratory defense mechanism
mucous, sticks onto pathogens. primary defense of lungs
Mucosa
lines nasal cavity through large bronchioles. controls balance. too little could cause respiratory problems.
Lamina propria
supports respiratory epithelium, has mucous to pick up pathogens. . underlying areolar tissue, mucous glands in trachea and bronchi
Mucocillary escalator
Cilia moves mucous up towards pharynx. mucus traps debris. swallowed to acids in stomach or be coughed up.
Cystic fibrosis
no mucocilliary escalator. It stops working. average life span is 37. heart failure or chronic bacterial lung infection.
Dorsum of nose
bridge formed by two nasal bones. supported by hyaline cartilage
nasal cartilages
small elastic cartilages extending laterally from bridge, help keep nostrils open
Paranasal sinuses
mucus secreted by these moistens/ clean nasal cavity. drains with tears through nasolacrimal duct.
Nasal septum
formed by vomer and perpendicular plate of ethmoid
Pharynx
throat. Shared by respiratory and digestive systems.
muscular propulsion of food into the esophagus. common passageway for solid food, liquids and air.
Naso
Oro- base of tongue.
Laryngo- hyoid to larynx
Trachea
windpipe. conducts air towards lungs. to bronchi. has 15-20 c shaped tracheal cartilages which prevent collapse and over expansion.
nasal vestivule
space at front of nasal cavity. coarse hairs trap large airborne particles.
Nasal cavity opens into nasopharynx through the ________
choanae
hard plate
forms floor of nasal cavity, operates nasal/oral cavities
soft plate
fleshy part posterior to hard plate
glottis
opening of larynx. voice box. where air passes through larynx. made of vocal folds and rima glottdis. vocal folds and vestibular folds (prevent foreign objects from entering glottis)
larynx
mostly cartilage, surrounds and protects glottis. three large cartilages: epiglottis, thyroid cartilage and cricoid cartilage
epiglottis
swallowing. larynx elevates, epiglottis folds back over glottis, blocks entry into respiratory tract
thyroid cartilage
anterior surface is laryngeal prominence.
cricoid cartilage
ring around larynx. protects glottis and larynx. provides attachment for laryngal muscles
cuneiform cartilage
between folds of tissue between each arytenoid cartilage and epiglottis
corniculate cartilage
work with arytenoid cartilages to open and close glottis
Arytenoid carteleges
superior surface of cricoid
vocal cords
think of guitar strings. vibration produces sound waves (your voice)
vocal folds
tissue folds that contain vocal ligaments
articulation
modification of sounds by tongue teeth and lips.
____ bronchus is wider than ____ and at a steeper angle. forign objects in trachea often go in it
right; left
sympathetic nervous system causes
bronchodialation
parasympathetic nervous system causes
brochioconstriction. asthma.
bronchioles
no cartilage. thick smooth muscle. segmental bronchi branch give rise to these.
terminal bronchioles lead to
pulmonary lobules or gas exchange
respiratory bronchioli are the ____division
last
lobar bronchi
2 in left lung 3 in right.
bronchioles ->
terminal bronchioles -> respiratori bronchioles -> pulmonary bronchioles. branch into smaller and smaller tubes. diameter decreases
Lungs
right- superior, middle and inferior lobe
left- superior and inferior lobe
right lung
horizontal tissue between superior/middle lobes, oblique fissure between middle/inferior lobes
left lung
oblique fissure between superior/inferior lobes
cardiac notch
left lung, accommodates pericardium / heart
hilum
medial depression on each lung. allows passage of main bronchus, pulmonary vessels, nerves, lymphatics.
alveoli
surrounded by elastic fibers which aid air movement and extensive capillary network for gas exchange
plurae
serous membrane sacs surrounding lungs
visceral plura
covers outer surface of lungs
parietal plura
covers inner surface of thoracic wall, extends over diaphragm and mediastinum
pleural cavity
potential space between visceral and parietal layers of plural sac. contains plural fluid which reduces friction
There are three major cell types in alveolar epithelium.
pnenmocytes type 1
pneumocytes type 2
Alveolar macrophages
Pnenmocytes type 1
thin delicate sites of gas diffusion
pneumocystis type 2
produce surfactant- oily secretion, reduces surface tension of water in alveoli to prevent collapses
alveolar macrophages
locate and phagocytize particles that could clog the alveoli
blood air barrier
where gas exchange occurs between blood and alveolar air. 2 layers
- alveolar cell layer (epitletlum)
- fused basement membranes (alveolar and capillary)
- capillary endothelium
external respiration
exchange of gases between blood, lungs, and external environment; gas diffusion occurs across blood air barrier between alveolar air and alveolar capillaries
pulmonary ventilation
breathing
internal respiration
occurs between blood and tissues. absorption of oxygen from blood. release of carbon dioxide by tissue cells
hypoxia
low tissue oxygen levels. severely limits metabolic activities
anoxia
no oxygen supply. much damage caused by heart attacks and strokes
atelectasis
lung collapse
air flows from an area of _____ pressure to an area of _____ pressure
higher; lower
inhalation
increased volume causes decreased pressure. air moves IN from an area of high pressure to low. intrapulmonary pressure
exhalation
decreased volume = increased pressure. air is forced out from an area of high pressure to low. intrapulmonary pressure>atmospheric pressure. positive intrapulmonary pressure pushes air out.
intrapulmonary pressure
pressure inside respiratory tract, usually measured at alveoli
tidal volume
volume of air moved into and out of lungs in normal breath.
external respiration: gas diffusion
alveolar mixture: increasing blood po2 (oxygen enters blood) as it goes from pulmonary capillaries to alveolus. decreases pco2 (carbon dioxide leaves blood). so in capillaries oxygen is less before it enters alveoli and carbon dioxide is more before it enters.
internal respiration: gas diffusion
oxygen of blood leaving lungs in pulmonary veins drops slightly when it mixes with blood from capillaries but its higher than oxygen of interstitial fluid. co2 is giver in tissues/interstitial fluid than in blood. co2 lowers pH of blood
Apnea
period in which breathing has stopped
respiratory system
works with cardiovascular system to supply oxygen and move carbon dioxide from cells
digestive tract
lined with permanent ridges and temporary folds. increase surface area for absorbing nutrients
mesentery
prevents entanglement of intestines, stabilizes attached organs, provides access rout for blood vessels, nerves and lymphatics.
there are ____ layers of the digestive tract
4
mucosa
layer 1 of DT. inner lining.
-lamina propria: areolar tissue. contains blood vessels, sensory nerve endings, lymphatic vessels, smooth muscle cells, lymphoid tissue and mucous glands
-mucosal epithelium: begins and ends with strafed squamous..
..stomach small intestine and large intestine are simple columnar with goblet cells.
-villi: small mucosal projections that increase surface area for absorbtion
submucosa
dense irregular connective tissue contains blood vessels and lymphatic vessels. also exocrine glands which secrete buffers and enzymes into digestive tract
muscular layer
smooth muscle in inner circular and outer longitudinal layer . mechanical processing and movement along tract
serosa
visceral peritoneum, in abdominal cavity. this us not in oral cavity, pharynx, esophagus or rectum.
peristalsis
contraction behind bolus to help move food down.
bolus
food entering in digestive tract
segmentation
movement along digestive tract
neural control mechanisms
-Short reflexes (myenteric reflexes)
Triggered by chemoreceptors or stretch receptors in digestive tract walls.
Controlling neurons located in the myenteric plexus
-Long reflexes
Higher level of control involving interneurons and motor neurons of the CNS.
Generally control large-scale peristalsis, moving material from one region of the tract to another.
May involve parasympathetic motor fibers that synapse in the myenteric plexus
hormonal control mechanisms
involves at least 18 hormones that effect digestive function. produced by enteroendocrine cells
local factors
primary stimulus for digestive activities. change of pH in lumen, presence of chemicals, physical distortion of digestive tract wall
small intestine
enzymatic nutrient dijestion and absorbtion. 90% of nutrient absorption. length: 19.7 feet/6 meters. duodenum, jejunum, and ileum.
large intestine
dehydration and compaction of indigestible materials
stomach
chemical breakdown and mechanical processing
ingestion
solid food and liquid enter oral cavity
secretion
release of water, acids, enzymes, buffers, and salts by the digestive tract epithelium and by accessory digestive organs
defecation
indigestible food is compacted into material waste called feces and are eliminated
oral cavity
digestion of carbs and lipids begins here, lined by oral mucosa
esophagus
narrowest point at beginning. enters abdominiopelvic cavity through the esophageal hiatus which is the opening in the diaphragm
innervation
in esophagus. maintains resting muscle tone in circular muscle layer, keeps lumen closed except when you swallow
upper esophageal sphinchter
prevents air from entering esophagus
lower esophageal sphincter
prevents back flow of stomach contents, normally is contracted
layers of esophageal wall
- mucosa and submucosa form large folds and allow for expansion with passage of a bolus
- muscularis externa: superior third is skeletal muscle, middle third is skeletal and smooth and inferior third is smooth muscle
- no serosa: adventitia of connective tissue actors esophagus to posterior body wall
stomach
empty: contracted lumen
full: can expand to contain 1-1.5 liters of chyme which is highly acidic soupy mixture formed from food saliva and gastric gland secretions
fundus
superior to junction between stomach and esophagus
cardia
medial portion. secretes mucus to protect esophagus from stomach enzymes/acid
body
largest region. between funds and pylorus. mixing bowl
pylorus
j sharpe. changes shape with mixing movements
functions of stomach
Temporary storage of ingested food
Mechanical digestion of ingested food
Chemical digestion of food through the action of acid and enzymes
Production of intrinsic factor
layers of stomach
- mucosa: alkaline mucus. protects epithelial cells against acid in gastric lumen. life span of gastric epithelial cell is 3-7 days
- submucosa
- muscular layer
- serosa
gastric glands
found in fundus and body: to acid gastric digestion. parietal and chief cells. secrete 1.5 L of gastric juice everyday.
in pylorus: secrete mucus and hormones that coordinate and control digestive activity
parietal cells secrete:
-Intrinsic factor Glycoprotein that aids in vitamin B12 absorption -Hydrochloric acid (HCl) Activates pepsinogen Keeps stomach at pH 1.5–2
g cells
produce hormones
chief cells secrete:
-Pepsinogen
Activated by HCl to become pepsin
Active proteolytic (protein-digesting) enzyme
-Newborns also produce rennin and gastric lipase
Enzymes important for the digestion of milk
HCI production
-Parietal cells do not create HCl in their cytoplasm (it would destroy the cell)
~~H+ and Cl– are transported and secreted separately
~~H+ is generated as carbonic anhydrase converts CO2 and H2O to carbonic acid
-Bicarbonate ejected into the interstitial fluid in exchange for a chloride ion
~~If gastric glands very active, amount of bicarbonate released is enough to increase the pH of the blood
-Chloride ions diffuse across cell and exit into the lumen of the gastric gland
-Hydrogen ions are also actively transported into the gastric gland lumen
Sudden influx of bicarbonate ions is called the
alkaline tide
many intestinal structures such as _____ and ____ add surface area to increase absorption
circular folds and intestinal villi
circular folds
along intestinal lining, 800 folds in small intestine. mostly in jejunum
intestinal villi
fingerlike projections of mucosa. covered by epithelial cells
intestinal glands
located at the bases of villi. stem cells divide an produce epithelia cells.
paneth cells
at base have a role in innate immunity. releases defensins and lysozyme
internal structure of villus
-capillary network in the lamina propria. carry absorbed nutrients to the hepatic portal circulation
- lacteal/lymphatic capillary: transports materials that cannot enter blood capillaries. . example:
1. Absorbed fatty acids assembled into protein–lipid packages (chylomicrons) too large to diffuse into bloodstream
2. Transported by lymphatic system to venous circulation - smooth muscle in muscular mucosae: moves villi back and forth exposing surfaces to intestinal content. squeezes lacteal, assisting in lymph movement
- brush border: increases surface area. carpet of microvilli on surface of epithelial cells. contains enzymes that direct materials so the epithelia cells can then absorb breakdown products
duodenum
closet to stomach. mixing bowl, it receives chyme from stomach and digestive secretions from liver, gallbladder and pancreas. duodenal glands produce mucous. has few circular folds and small villi. main function: neutralize acidic chyme.
jejunum
middle segment. peritoneal cavity. numerous circular folds, long villi. has majority of chemical digestion and nutrient absorption
ileum
ends at ileocecal valve which is a sphincter controlling flow from the ileum into the cecum of large intestine. has few circular folds and villi are stumpy.
gas exchange
- breathing moves air in/out of lungs
- oxygen diffuses from alveoli in lungs into capillaries
- oxygen enters red blood cells, where it binds to protein hemoglobin.
- oxygen diffuses from blood to body’s tissues, and carbon dioxide diffuses from the
tissues to the blood. - carbon dioxide leaves the body when we exhale
Carbon dioxide transport
- Carbon dioxide is released from mitochondria
- Carbon dioxide diffuses into a capillary
- Carbon dioxide Is carried to the lungs
- Carbon dioxide diffuses into a alveolus
- Air exits through the nose or mouth
Oxygen transport
- Oxygen diffuses from the alveoli into surrounding capillaries
- Oxygen enters a red blood cell
- Oxygen binds to a molecule of hemoglobin
- Oxygen carried through blood vessels to a capillary
- Oxygen diffuse from the blood to the body’s tissues
