4/22- Respiratory System (Exam 4) Flashcards
What is the respiratory system?
Lungs and pipework into lungs
Gas exchange
System that oxygenated the blood and removes CO2
What are the 2 parts of the respiratory system?
1) respiratory zone- gas exchange
2) conducting zone- all of the pipe work leading into lungs (trachea, bronchi and bronchiole)
What are the 3 functions of the conducting zone?
1) filters the air you inhale (filtration)
2) warms air
3) humidifies the air
What is filtration?
Air is filled with particular matter that cannot get into lungs it will clog them
What are examples of filtration?
1) nose hairs- removes large particles
2) pseudostratified columnar epithelium- have cilia and goblet cells
What do goblet cells secret and explain
Mucus
Lives in most of the respiratory system
Sticky and tough
Mucus goes to back of throat with particles and you either swallow it or spit it out
What is the nasal conchae (concha) or turbinates?
Creates turbulence in the air you inhale in nasal cavity
Air swirls around making particular matter go across mucus surfaces and a lot is trapped
Delays air going to trachea
What is the warming of the air?
Homeostasis
Body temp 98.6 Fahrenheit
To not lose core body temp
What is humidification or moistening of air?
Atmosphere air is dry
Simple squamous epithelium can dry out of air is not humidified
What kind of tissue is the alveoli?
Simple squamous epithelium
What is Boyle’s law?
In a sealed container the pressure of a gas is inversely proportional to the volume
Volume increases pressure decreases
Volume decreases pressure increases
What is a direct consequence of Boyle’s law?
Movement of air in and out of the lungs
What are the muscles used in quiet respiration?
1) diaphragm- thong sheet of muscle separating the thoracic and abdominal cavity
2) external intercostals
When you inhale how is the diaphragm?
Diaphragm drops down
Increases volume of the chest cavity
What happens when the external intercostals when contracted?
Ribs pulls on rib cage and it rises up
Sternum is pushed out when contracted expanding volume of the chest cavity
What happens when the external intercostals are relaxed?
Angle downward
What happens when pressure drops below atmospheric pressure ?
Air forces it’s way down into your lungs and you inhale
When you exhale and rest the diaphragm how is it?
Diaphragm pops back up
Decreases volume of the chest cavity
When you exhale what happens to the external intercostals?
Rib cage drops and sternum comes in
Chest cavity volume decreases
What happens when the pressure is is greater than the atmospheric pressure?
Air comes out
What muscles does forced respiration, inspiration and/ or inhalation use?
Diaphragm
External intercostals
Sternocleidomastoid
Pectoralis minor
How is the sternocleidomastoid used for forced respiration?
Jerks up on the sternum and clavicle
Expands the rib cage
How is the pectoralis minor used for forced respiration?
Jerks up on the ribs
What muscles does forced expiration or exhalation use? And how are these muscles used?
External and internal abdominal obliques
Transverse abdominus
Rectus abdominus
When contracted they compress internal organs and move upward under diaphragm
What are 3 physical factors that affect the functioning of the lungs?
1) compliance- good needs to be maximized
2) elasticity- good needs to be maximized
3) surface tension- bad needs to be minimized
What is compliance?
Stretchability
Needs to expand lungs as much as possible
Lung tissue is 100x more stretchable than rubber
What is elasticity?
Ability to return to ones original size and shape
Ex: rubber bands
Lungs need to be able to return back to normal size for the air to leave
Elastic fibers- composed of elastin that criss cross through lung tissue
What is surface tension?
Needs to be reduced as much as possible
Problem in alveoli/ alveolus
What are alveoli?
Microscopic
Close to one another
Inside moist with sheet of water
Crush shot- no gas exchange
Smaller they become- bigger problem
Do alveoli need to be tiny?
Yes a lot of surface area- tiny alveoli
Increase surface area need to make them as small as possible
However, smaller worse surface tension and likely they will collapse
What is surfactant?
Surface active agent
Gets between water molecules
Prevents water from forming hydrogen bonds
Smaller the alveoli the better it works
Produced during 8 month of pregnancy
What is type 1 cells?
Simple squamous epithelium (thin)
Most alveoli composed of this
What is type 2 cells or septal cells?
Thicker than type 1
Not good for exchange surface
Secret surfactant
What is respiratory distress syndrome?
Premature babies don’t make surfactant
Alveoli collapse
Treated with- mechanical respirators force alveoli to open and to administer surfactant
What is control respiration?
How is breathing controlled
1) local control- within lungs
2) brain- involuntary and voluntary
What is local respiration?
Exerted within lung
Happens in 2 places
1) alveolar capillaries
2) bronchioles
What are alveolar capillaries?
Capillary networks that surround alveoli
Constrict if alveoli doesn’t have enough O2
Prevents blood from entering
Forced blood to go elsewhere
What are bronchioles?
Very small passageways
Most of wall is smooth muscle (allows for constructing and dilation)
Air high CO2 bronchioles dilate to let fresh air in
Where is the brains involuntary control center?
Medulla oblongata
Pons
What is the rhythmicity center?
Sets the basic background pace of breathing
What is tidal breathing?
Basic relaxed breathing in and out
What does the pneumotaxic and ape rustic centers do?
Slows down or speeds up breathing
What are the receptors that signals the brain how to breathe?
Chemoreceptors
Baroreceptors
Stretch receptors in the lungs
What are chemoreceptors?
Measure CO2 and O2
In carotid arteries, aorta and chemosensitive area of the brain (medulla oblongota)
What does the chemosensitive area of the brain measure?
Measure CO2 and O2 in cerebral spinal fluid (CSF)
CO2 high O2 low= breathe more quickly
CO2 low O2 high= rate of breathing slows down
What is hyperventilation?
Breathing more quickly then the physiological situation requires
Caused by fear or caffeine
What is tachypnea?
Fast breathing
Physiologically appropriate
Ex: working out
What is hypoventilation?
Respiratory rate is slower than it should be than the physiological situation requires
Caused by alcohol and morphine
What are baroreceptors?
Measure blood pressure
Bp low- rate of respiration high (breathe more quickly)
Bp high- rate of respiration low (slows down)
What is Hering- Breuer Reflexes?
Stretch receptors are responsible
2 of them
1) inflation reflux
2) deflation reflux
What is inflation reflex?
If you draw in too much air
Inflate lungs where damage can occur
Stretch receptors triggered
Immediately stop inhaling and force you to exhale
What is deflation reflex?
Blowing everything out of lungs
Deflate till damage can occur
Stretch receptors stop you and make you inhale
What is voluntary control and the 2 ways?
Under cerebrum
1) bypass little computers and send instructions consciously down spinal cord and take conscious control of breathing
- done with singing and talking
2) send instructions to the computers and tell them what to do
- when you hold your breath
