T2.1-Exercise physiology:Ventilatory system

Top to bottom composition of the respiratory system

Nose

Mouth

Pharynx

Larynx

Trachea

Lungs

Bronchi

Bronchioles

Nose function/characteristics

Take in / out air, can warm up the air

Hairs to trap foreign pathogens/dust

Mouth function/characteristics

Breathing, hydration, communication

Mouth inhaled hair hits the bronchi, often drier+ colder causing constriction

Pharynx function/characteristics

Carry’s air, food+ fluid down from the nose and mouth. Pushes food into the espophpgus so it’s not breathed in

Larynx function/characteristics

Contains vocal chords, let’s air pass from you pharynx to trachea

Trachea

Passage for air which moistens and warms it before it passes into the lungs. Prevents bronchi constructing allowing more air through

Bronchi

Main passageways into the lungs, lined with mucus to trap pathogens

3 functions of the conducting airways

Low resistance pathway for air flow eg. Trachea solid open structure

Defense against chemicals and other harmful inhaled substances

Warming and moistening the air to prevent lung constriction

Pulmonary ventilation (VE)

(Breathing)Inflow and outflow of air between the atmosphere and lings

Total lung capacity

Volume of air in the lungs after maximum inhalation(everything)

Vital capacity

total amount of exchangeable air)

Tidal volume

Volume of air breathed in and our

Expiratory reserve volume

Volume of air in excess of tidal volume that can be exhaled forcibly

Inspiratory reserve volume

Additional inspired air over and above tidal volume

Residual volume

Volume of air still contained in the lungs after a maximum exhalation

Mechanics of breathing in

Diaphragm and external intercostals contract so rinçage rises up and outwards. Diaphragm lowers and becomes flatter. Volume of chest cavity increases therefore pressure decreases, air moves into the lungs from the atmosphere. Active process

Mechanics of breathing out

Diaphragm and external intercostals relax, rob cage is lowered. Diaphragm raises due to a push from abdominal organs, volume of chest cavity decreases and therefore pressure increases so air is forced out of lungs into the atmosphere. Passive process

Lung stretch receptor

Increased exercise triggers lsr when the lungs expand and initiate a signal (sent to the CNS) which co- ordinates a response; the rate of breathing increases

Muscle proprioreceptors

. sense when tissues are stretched or experience tension and pressure. Sends signal to CNS to increases rate of ventilation

Chemoreceptors

Sense changes in the chemical composition of the blood. sends a signal to the CBS to increase rate of ventilation for removal of Lactic acid and CO2

Hemoglobin

The iron containing oxygen transport proteins in red blood cells

How much oxygen can harm oblivion carry

Binds to 4 oxygen molecules in humans (oxyhemoglobin)

How do the mechanics of breathing change during exercise

Muscle proprioreceptors, chemoreceptors lung stretch. Receptors

Additional muscle use eg the abdominals

explaion the process of oxygen exchange at the alveoli

high concentrations of oxygen in the alveoli compared to the blood leads to a concentration gradient. o2 diffuses from a high concentration to a low concentration via the capillaries. Exercise exaccerbates the demand for oxygen as muscles require more oxygen for respiration