Respiratory System Flashcards
Why does the esophagus have multiple layers of cells?
For protection against harsh foods
What is peristalsis?
The smooth muscles in the small intestine that work like a marble in a hose, pinching it forward.
Also found in the esophagus to help food move through.
What is segmentation?
The smooth muscles in the small intestine pinch food back and forth to mix them up. This helps more if it come in contact with the surface for absorption.
What is the purpose of bile salts?
They are inserted to fat to prevent the fat all coming together. Lipids with bile salts attached are called micelles, which are something that we can absorb.
What is the role of bile?
To emuslify
What are three main functions of respiration?
Supply body with oxygen, move carbon dioxide outside, provide acid base buffering
Does exchange happen in conducting zones?
No!
What happens in respiratory zones?
Oxygen is moved into the blood.
What are the 5 steps of respiration?
- Pulmonary ventilation
- External respiration
- Transport of respiratory gasses
- Internal respiration
- Cellular respiration
What happens during pulmonary ventilation?
Air moves in and out of the lungs
What happens during external respiration?
Gas exchange in lungs
What happens during transport of respiratory gases?
Gases in blood transported from lungs to body cells and back to lungs
What happens during internal respiration?
Exchange of gases at body capillaries and cells (O2 unload, CO2 load)
What happens during cellular respiration?
Use of oxygen by cells to produce energy (production of CO2)
If Atmospheric pressure is 760 mm Hg, what would intrapulmonary pressure be?
760 mmHg
At rest, what is the relationship between Ppulm and Pplur?
At rest, intrapulmonary pressure is always going to be greater than intrapleural pressure.
What is Boyle’s Law?
Pressure and volume are inversely related
P1V1 = P2V2
What are the forces acting to make lungs collapse?
Elasticity and surface tension
What is transpulmonary pressure?
The difference between Ppulm and Pplur. Transpulmonary pressure keeps the lungs inflated, prevents them from collapsing
Explain how air moves into the lungs.
When we breathe we lower our diaphragm which increases volume in the lungs so pressure in lungs decreases. When this pressure decreases, air moves in the lungs until equilibrium.
Explain how air moves out of the lungs.
Diaphragm goes back up when we relax which decreases volume in the lungs which increases the pulmonary pressure. When Ppulm is greater than Patm, the air moves out.
What is Ohm’s law?
Flow = Change of pressure / Resistance
What is the difference between obstructive and restrictive disorders?
Anything that slows down air movement is obstructive disorder, like asthma
Anything that restricts movement is a restrictive disease
What is lung compliance? Give examples.
Lung compliance means how easily the lungs expand.
Lungs with a lot of scar tissue have low compliance
Too elastic lungs have too high compliance
What is carbon dioxide once it enters the blood?
Carbonic acid
Why do alveoli have thin walls?
Thin walls of alveoli allows for quick diffusion of oxygen and carbon dioxide. Alveoli are very small for higher surface volume.
What is anatomic dead space?
Anatomic dead space is the conducting zone that we have to move air in and out with, but it doesn’t actually do anything. About 150mL with each breath.
What is physiologic dead space?
Physiologic dead space is loss of exchange capacity due to pathology, like if you lose a lung or have a tumor taking up space.
What is the majority of oxygen in the blood bound to when transporting?
98.5% of the oxygen that is transported in the blood in bound to hemoglobin. Only 1.5% is dissolved into plasma.
How many oxygen atoms are bound to a single hemogloben?
4!
Is oxygen binding the Hb a reversible process?
YES! If oxygen cannot fall off then it can’t do anything.
What is Hb called when is has all four oxygen atoms bound to the heme?
Saturated Hb
What is Hb called when only 1-3 oxygen atoms are attached to the hemes?
Partially saturated hemoglobin
When blood circulates and leaves the lungs it is 100% saturated. Why would it be 60% when it returns?
If they are working out or have a need for more oxygen
What are some factors that affect Hb saturation?
Temp, oxygen level, ph of the blood, CO2 content, BPG (waste product)
When CO2 diffuses into bloodstream, what percent remains dissolved in plasma?
Only 7%
What percent of CO2 diffused in the bloodstream diffuses into RBCs?
93% diffuses into RBCs
After 93% of CO2 is diffused into the RBCs, what percent of that is carried as carbonic acid?
70%
What happens to 23% of the CO2 that is diffused into RBCs?
23% binds to Hb, forming carbaminohemoglobin
What does Dorsal Respiratory Group do?
Sends the signal to the diaphragm to contract
What does Ventral Respiratory Group do?
Forced inspiration and expiration to help with deeper breathing
What do Pons centers do?
Plays a role in smoothing the breathing system.
What are the five basic processes to accomplish digestive system function?
- Mechanical processing and movement
- Secretion of fluid, digestive enzymes and hormones, and bile, acid, alkali, and mucus.
- Digestion
- Absorption
- Elimination
What is the cephalic phase in the digestive system?
Sense- sound, sight, and smell
What is the Pharynx?
Common passageway for air and food
What does the epiglottis do?
Closes the airway temporarily so food will not enter the trachea
What is chyme?
Chyme is a water mixture of partially digested food and gastric juice that is delivered to the small intestine
Does the stomach absorb nutrients?
No!
What percent of food is absorbed in the small intestine?
90%
What is the muscle that helps hold food in the stomach at the top?
Cardiac sphincter
What is the muscle that helps hold food in the stomach at the bottom?
Pyloric sphincter
What does the pyloric muscle do?
It regulates chyme leaving the stomach
What is the food you swallow called?
Bolus
What is the slurry of food and acid in your stomach called?
Chyme
What does the pancreas do?
Secretes bicarb which neutralizes the acid in chyme.
What are the 3 enzymes that the pancreas secretes to aid in digestion?
Lipase- breaks down lipids
Protease- breaks down proteins
Amylase- breaks down carbs
Where is amylase found?
Saliva and pancreas
What do we add in the stomach to aid in breakdown?
Acid and pepsin
What is the exocrine function of the pancreas?
Releases enzymes
What is the endocrine function of the pancreas?
Insulin/glucagon, which are hormones
What duct does bile go through immediately after exiting the liver?
Hepatic duct
What duct leads from the liver to the gallbladder?
Cystic duct
What duct releases bile down to the small intestine?
Common bile duct
Is the pancreas a gland?
Yes because it can secrete
Is the gallbladder a gland?
No because it doesn’t secrete, it is just a storage space for bile.
What does the hepatic portal vein do?
It brings back all nutrients to be processed in the liver before blood go back to the inferior vena cava.
Is blood that enters the liver the same when exiting?
No, because it filters it a lot.
What hormone is released from the stomach and what does it do?
Gastrin, signals the stomach to squeeze to begin digestion
What are the two hormones from the duodenum?
Secretin and CCK
What does secretin do?
Signals to release bicarb and slows down stomach contraction
What does CCK do?
Sends a signal to the liver to secrete bile
Bile from the liver and digestive juices from the pancreas enter which section of the small intestine?
The duodenum
Structurally, the human liver is divided into how many lobes?
4
