respiratory system

Respiratory system

• meant to regulate the pH of your blood

• based off of CO2

Pulmonary Ventilator

• moving air in and out of the lungs

Boyles Law

• pressure increases, volume decreases

• pressure decrease, volume increases

Types of Respiration

• External Respiration

  • diffusion of gases between lungs and blood

    • oxygen and carbon dioxide

    • diffusion of both gases occur at the same time

• Internal Respiration

  • diffusion of gases between blood and tissues

• Cellular Respiration

  • sugar (C6H12O6) + 6O2 →6CO2 + 6H2O + ATP

CO2 + H2O →H2CO3 (carbonic acid)

• if you can’t make enough carbonic acid your pH goes up

Breath in 20% of oxygen, 80% nitrogen

• breathe out the nitrogen

Vibrissae (nose hairs)

• filters coarse materials

Conchae (parts in the nosal cavity)

• mixes incoming air

Pharyngotympanic Tube

Uvula

• flattens so food and liquid don’t go upto into your nose when you swallow

Hard Palate

• divides nasal and oral cvity

Pharynx

• common pathway for food and air

  • nasophayrnx - back of throat

  • orophyarynx -

  • laryngopharynx

Larynx

• voice box / adam’s apple

  • epiglottis - cartilage

  • hyoid bone

  • thryoid cartilage(1)

  • cricoid cartilage(2)

  • tracheal cartilage

• vocal chords - can stretch or go slack to change voice tone

Trachea

• 1-12 cartilaginous rings

• Trachea split into

  • primary bronchus

  • secondary bronchi

  • tertiary bronchi

Lungs

• The left lung is smaller because it gets crowded by the heart

  • 2 lobes & 1 fissure

• right lung

  • 3 lobes & 2 fissures

• lobes are connected by fissures

• Cilitated to move the bad things away from the lungs

Collapsed Lung

• when the lung rips away from the rib cage

Pleura

• pleura → pleural cavity →muscle →rib →skin → fat

• visceral pleura →serous fluid →parietal pleura → ribs & intercostal muscles

  • attaches to rib and diaphragm

Bronchioles & Alveoli

• Bronchioles - end of the airway

• Alveoli - where O2 and CO2 exchange

  • no cartilage (smooth muscle to keep airways open)

  • wrapped up by thousands of capillaries

  • the more membrane there are the more gases can be exchanged

  • Type 1 cells : alveolar wall, simple squamos epithelium

  • Type 2 cells : secrete surfactant (detergent that breaks up water cohesion)

• Respiratory membrane - thinnest tissue possible for the quickest diffusion

Henry’s Law

• when a mixture of gases is in contact with a liquid, each gas will dissolve in the liquid in proportion to its partial pressure

• the amount of gas that will dissolve in a liquid also depends upon its solubility

• various gases in air have different solubility

  • carbon dioxide is the most soluble

  • oxygen is 1/20th as soluble as carbon dioxide

  • nitrogen is practically insoluble in plasma

    • can’t get into blood stream, only way to get it in is through eating, breathe in 80%

Oxygen Transport

• molecular oxygen is carried in the blood

  • bound to hemoglobin within rbcs (~98%)

  • disolved in plasma (~2%)

• Role of hemoglobin

  • each Hb molecule binds 4 oxygen atoms in a rapid and reversible process

  • the hemoglobin-oxygen combination is called (HbO2)

  • hemoglobin that has released oxygen is called reduced / deoxyhemoglobin (HHb)

  • Heat weakens hemoglobin and oxygen bond

    • regions of the body that work the hardest get the most oxygen

• Hemoglobin

  • rate that hemoglobin bins and releases oxygen is regulated by

    • Po2, temperature, blood ph, and Pco2 (P = partial pressure)

      • ensure adequate delivery of oxygen to tissue cells

Carbon Dioxide Transport

• carbon dioxide is transported in the blood in three forms

  • dissolved in plasma - 7 to 10%

  • chemically bound to hemoglobin - 20% is carried in RBCs as carbaminohemogolbin

  • Bicarbonate ion - 70% is transported as bicarbonate (HCO-3)

    • almost immediately taken by the RBCs

    • helps with regulating pH

98% of oxygen is carried in RBCs, 90% of carbon dioxide is carried in RBCs

Chemoreceptors - primary

• sense high CO2

• can tell the brain to breathe out CO2

  • the CO2 mixes with the water and can make the blood acidic → makes the brain irritated so it wants the body to breathe it out

  • need carbonic acid to let the receptor breathe to breathe in CO2

  • aortic / charotic body - receptors that can detect less O2

Peripheral chemoreceptors - secondary

• sense low O2 levels

Two parts of medulla control inner breathing

• Dorsal respiratory group - INVOLUNTARY

  • tells diaphragm to contract

  • increase chest volume → breathe in

  • passive breathing

• Ventral - VOLUNTARY

  • can control your breathing

  • breathe in

PRG - regulates how deep you breathe

DRG - how often you breathe in

No part of your brain says breathe out

Lung Volumes

• Tidal volume - breathe in / out

  • ½ a liter of air - saturates 98%-99%

• Expiratory Reserve - left over air from tidal volume

• Inspiratory - added air that can be taken in before a full breath

• Vital Capacity - most amount of air that can be taken in

• Residual - left over air after a whole breath which keeps lungs and alveoli from collapsing

Lung Cancers

• squamous cell carcinoma

  • can come from breathing in pollution

  • these cells come in contact with the pollution

• adenocarcinoma

  • cancer of cells that make the fluids of the respiratory system

  • almost always found from second hand smoke

  • usually easy to remove

  • deforms the chest

• small cell carcinoma

  • found in smokers

  • deforms the chest