Exam 3

where does the the respiratory and digestive tract diverge?

larynx

opening of trachea

glottis

vocal chords

ligaments covered in stratified squamous epithelium in inside of larynx- controlled by skeletal muscles

which cranial nerves innervate the throat?

glossopharyngeal and vagus (9+10)

Where are vocal chords anchored?

arytenoids to thyroid cartileges

What is epiglottis attached to and what is it composed of?

attached to thyroid cartilege and composed of elastic cartilege

vocal chords tighten

to make higher pitched sounds

the trachea is lined with

pseudo stratified columnar epithelia

mucociliary escalator

cilia in trachaea are sweeping mucous up towards the larynx

Where does trachea divide at? Where does it enter the lungs at?

divides at carina- enters lungs at hilum

bronchioles are composed of

simple cuboidal epithelium

respiratory zone

where gas exchange occurs- respiratory bronchioles and alveoli

alveoli composed of

simple squamous epithelium with elastic tissue around them

What is the role of alveoli-made surfactant?

it counteracts surface tension of water

How much air can you hold in your lungs

6 Liters (3 in each lung)

heart and lungs have a ____ membrane around them, which allow the lungs to move without creating friction

serous

Which pleura helps inflate our lungs as we inhale

parietal pleura

What is the relationship between the intrapulmonary pressure and the intrapleural pressure? What is the role of intrapleural pressure?

intrapleural pressure is 3-4 less than intrapulomary

to keep the lungs partially open

negative intrapleaural pressure is trying to counteract

1. elastic recoil of lung tissue, alveoli collapse in

2. surface tension created by fluid in alveoli

internal intercostals aid with ___

external intercostals aid with ___

exhalation, inhalation

What is the difference between vital capacity and total lung capacity?

total lung capacity includes vital capacity and residual volume

In alveoli, what is the relative pressures of O2 and CO2

O2 pressure is high in respiratory membrane so oxygen moves into blood

CO2 pressure is high in pulmonary capillaries so CO2 diffuses into alveoli

O2 and CO2 relative pressures in arterial and venous ends of capillaries

O2 greater in arterial

CO2 greater in venous

increased pressure of CO2 means pH….

drops

What percent of Oxygen is offloaded to available tissues?

25%

What could make blood cells release more oxygen?

An increase in temperature (exercise, fever)

when partial pressure of CO2 is too high,

blood drops below 7.35

what enzyme inside the red blood catalyzes CO2 and water to make carbonic acid>

carbonic anhydrase

dorsal respiratory group

uses sensory input to modify basic rate of breathing from VRG

ventral respiratory group

drives respiration

pontine respiratory centers

smooth breathing

What muscle controls breathing and why?

Skeletal because its voluntary

chemoreceptors

respond to CO2 intake, monitoring partial CO2 pressures and blood pH levels

high CO2 levels means, can lower oxygen trigger same response?

more H ions

no

What are afferent responses to partial pressure CO2 increase?

decrease blood pH

chemoreceptors in medulla, carotid, and aortic bodies respond

What are the efferent responses/physiological to partial pressure of CO2 ?

ventilation, increase CO2 exhaled

physical and chemical functions of the digestive system

physical: ingestion
mastication
propulsion/peristalisis
mixing
transport
elimination
chemical: secretion

digestion

absorption

regulation

what are the visceral and parietal layers of the serous membrane of the abdominopelvic cavity seperated by?

peritoneal cavity containing serous fluid

What is the mesentary and what is its role?

2 fused sheets of serous membrane from body wall to digestive organs
route for blood vessels, nerve, lymph vessels

holds organs in space

Organs not suspended by mesentery are ____

retroperitoneal

kidneys, pancreas, colon

Splanchnic circulation

arteries from celiac trunk, venous hepatic portal, and mesenteric arteries

4 layers of digestive tract

mucousa

submucousa

muscularis externa

serousa

mucousa 3 layers

mucousal epithelium

lamina propria

muscularis mucosa

2 major plexuses of digestive system

myenteric and submucousal

How does the enteric nervous system communicate with the CNS and the ANS?

CNS through afferent visceral fibers

enteric nervous system functions with little oversight from CNS

ANS through motor fibers

What are the muscles of mastication?

temporalis

masseter

medial and lateral pterygoids

oropharynx and laryngopharynx are lined with

mucous secreting stratified sqamous epithelium

esophageal hiatus

where the esophagus passes through the diaphragm

Where does the esophagus run to and from?

Runs from the level of the cricoid to stomach and lies posterior to the trachea.

Where does the esophagous join the stomach?

the gastroesophageal junction

2 phases of deglutition and what are the controlled by

buccal by skeletal muscles and pharyngeal by smooth muscle

What part of the body is responsible for GERD?

lower esophageal sphincter

rugae

folds in mucosa and submucosa to increase surface area

what are the pits of mucosa made of and what are they called?

gastric glands - simple columnar cells

endocrine cells

mucous neck cells

parietal cells (secrete intrinsic factor for B12 + HCl to lower pH)

chief cells (secrete pepsinogen)

what do the endocrine cells in the gastric glands secrete?

gastrin, histamine, endorphins, serotonin

3 parts of gastric secretion

1. cephalic

2. gastric

3. intestinal

cephalic phase stimulation and inhibition

1. sensations of taste, smell

2. lack of stimulation to parasympathetic nerves

gastric phase stimulation and inhibition

triggered by gastric distention, amino acids and proteins in the stomach and rising pH→gastrin positive feedback

low pH inhibits

intestinal phase stimulation and inhibition

chyme in duodenum stimulates

secretin, gastric inhibitory peptide, and cholecystokinin inhibits gastric secretions

What digestion finishes in the small intestine and where are products absorbed in the small intestine?

protein and carb digestion finished in SI

absorbed in capillaries in the submucosal layer, pass through hepatic portal vein into liver

what digestion begins and ends in the SI and what is it absorbed by?

lipid digestion

lacteals

How much urine does a person make in a day?

1-2L

primary extracellular cation

sodium

examples of water moving out of intracellular compartment

dehydration

diarrhea

drop in blood volume

common type of acid/base imbalance

respiratory acidosis

dehydration occurs when

fluid moves from the intracellular into the extracellular component

Which of the following buffer systems is most effective at the level of the nephrons?

phosphate buffers

what metabolic and respiratory condition is a person likely to have after vomiting for 12 hours?

metabolic alkalosis

decrease in respiration and rising PCO2 levels

entry of bile and pancreatic enzymes into the duodenum is controlled by

hepatopancreatic sphincter

function of hepatic portal circulation

collect absorbed nutrients for metabolic processing or storage before releasing them to circulation for cellular use

Where do the pancreatic acinar cells secrete digestive enzymes?

Into the pancreatic duct

stimulus for bile secretion by gallbladder

fats in the duodenum

primary cells in liver responsible for filtering and processing nutrient rich blood

hepatocytes

upper esophageal sphincter function

prevents aspiration of gastric contents in trachea

gastric phse of digestion stimulated by

stomach distention

serousa is _____

visceral peritoneum

what do gastric glands produce?

pepsinogen
intrinsic factor

accesory glands