Science Olympiad 2023 Anatomy and Physiology (Respiratory System)

Functions of the respiratory system

Functions of the respiratory system

protection, ventilation, respiration, regulating blood pH, speech

Diaphragm

a powerful muscle fixed to the lower ribs, sternum, and lumbar vertebrae that controls the respiratory system

intercostal muscles

Muscles that move the rib cage during breathing

quiet breathing

muscles contract to let air in and relax to let air out

forced breathing

muscles contract to let air in and out

upper respiratory system

nostrils, nasal cavity, mouth, pharynx, larynx

lower respiratory system

trachea, bronchi, bronchioles, alveoli

nostrils

where air enters and exits the respiratory system

respiratory mucosa

tiny cilia in the nasal cavity that move dirty mucus towards the outside of the nostrils

Sinuses

air-filled spaces in the skull that open into the nasal cavity to receive air

Pharynx

throat; passageway for food to the esophagus and air to the larynx

nasopharynx

top part of the throat where the nasal cavities drain

hard palate

bony plate that separates the oral cavity from the nasal cavities

soft palate

soft part on the roof of the mouth

oropharynx

extends from the uvula to the hyoid bone

Epiglottis

a flap of cartilage that guides air to the trachea or food to the esophagus

laryngopharynx

lower part of the throat adjacent to the larynx

Larynx

voice box

Trachea

a tube that runs from the larynx to just above the lungs

primary bronchi

branches of the trachea behind the sternum that enter each lung

Lungs

large paired organs on either side of the heart

heart

A hollow, muscular organ that pumps blood throughout the body.

Mediastinum

cavity between lungs

visceral plurae

cover the outer surface of the lung

parietal pluerae

cover the inside surface of the thoracic cavity

pleural cavity

contains the lungs

intrapleural fluid

lubricates the pleural surfaces

Bronchi

secondary and tertiary branches

Bronchioles

smallest branches of the bronchi

alveolar sacs

grape cluster-like structures at the end of the smallest bronchioles

Alveoli

tiny sacs of lung tissue specialized for the movement of gases between air and blood

respiratory membrane

the single layer of cells that makes up the wall of the alveoli

spirometer

instrument used to measure breathing

normal breathing rate

12-20 breaths per minute

Tidal Volume (TV)

Amount of air that moves in and out of the lungs during a normal breath

Normal tidal volume

500 mL

Inspiratory Reserve Volume (IRV)

maximum amount of air that can be inhaled after a normal inhalation

normal inspiratory reserve volume

3000 mL for males; 1900 mL for females

Expiratory Reserve Volume (ERV)

the volume of additional air that can be forcibly exhaled after a normal exhalation

normal expiratory reserve volume

1200 mL for males; 700 mL for females

Residual Volume (RV)

Amount of air remaining in the lungs after a forced exhalation

normal residual volume

1200 mL for males; 1100 mL for females

Functional Residual Capacity (FRC)

ERV + RV

normal functional residual capacity

2400 mL for males; 1800 mL for females

Inspiratory Capacity (IC)

TV + IRV

normal inspiratory capacity

3600 mL for males; 2400 mL for females

Vital Capacity (VC)

TV + IRV + ERV

normal vital capacity

4800 mL for males; 3100 mL for females

Total Lung Capacity (TLC)

IRV + TV + ERV + RV

normal total lung capacity

6000 mL for males; 4200 mL for females

pulmonary ventilation

movement of air into and out of the lungs

alveolar ventilation

the amount of air that reaches the alveoli

gas exchange step 1

Oxygen in air dissolves into fluid lining alveoli and diffuses through alveolar wall and capillary wall

gas exchange step 2

Oxygen enters blood plasma inside capillary. Gas exchange occurs in capillary beds

gas exchange step 3

Oxygen binds to oxyhemoglobin in red blood cells

gas exchange step 4

Carbon dioxide diffuses out of blood plasma and into air in alveolus

gas exchange step 5

Oxygenated blood leaves heart and circulates through capillaries to tissue

gas exchange step 6

Red blood cells arrive at tissue, rich in oxygen that binds to the hemoglobin in the tissue

gas exchange step 7

Oxygen leaves hemoglobin in red blood cells and diffuses across blood capillary walls and into tissue cells

gas exchange step 8

Carbon dioxide diffuses out of tissue into blood plasma, which carries red blood cells into lungs. Completely dissociated hemoglobin enters lung in red blood cells ready to be oxygenated

How are gases carried in the blood?

In the blood plasma or combined with hemoglobin

Asthma

inflammatory disorder of the airway walls associated with a varying amount of airway obstruction

Does childhood asthma occur more frequently in males or females? Why?

More common in males because the airway is smaller than females until the age of 20

Asthma triggers

Animals, dust, changes in weather, chemicals in the air or in food, exercise, mold, pollen, respiratory infections, stress, tobacco smoke, aspirin & other nonsteroidal anti-inflammatory drugs (NSAIDs)

Asthma symptoms

cough with or without mucus, shortness of breath, wheezing, and chest pain

chronic obstructive pulmonary disease (COPD) types

chronic bronchitis and emphysema

COPD

gradual decrease in the ability to push air out of the lungs

COPD causes

smoking, genetic mutation, and exposure to airborne irritants

COPD symptoms

severe coughing, shortness of breathe, sputum production, fatigue.

Emphysema

A serious disease that destroys lung tissue and causes breathing difficulties.

Emphysema causes

long term exposure to airborne irritants

Emphysema symptoms

shortness of breath, chronic cough, fatigue, barrel chest

cystic fibrosis

a genetic disorder that causes thick, sticky mucus to build up in the lungs, digestive tract, and other areas of the body

cystic fibrosis cause

genetic mutation

cystic fibrosis symptoms

fever, increased coughing and shortness of breath, loss of appetite, increased sputum, and sinus pain/pressure caused by infection or polyps

pneumonia

infection of the lungs

Pneumonia causes

bacteria, viruses, fungi

Pneumonia symptoms

cough, chills, shortness of breath, confusion, excess sweating, clammy skin, headache, loss of appetite, low energy, fatigue, chest pains

sleep apnea types

obstructive, central, complex

obstructive sleep apnea

the muscles that support the soft tissues in the throat, such as the tongue and soft palate, temporarily relax during sleep, constricting the airway

central sleep apnea

disruption in signals sent from the brain that regulate breathing cause periods of interrupted breathing during sleep

Complex Sleep Apnea

a combination of obstructive and central sleep apnea

sleep apnea symptoms

daytime hypersomnia, loud snoring, observed episodes of breathing cessation during sleep, abrupt awakenings accompanied by shortness of breath, awakening with a dry mouth or sore throat, morning headache, insomnia

chronic bronchitis

inflammation of bronchi persisting over a long time; type of chronic obstructive pulmonary disease (COPD)

acute bronchitis

a temporary inflammation of the bronchi

bronchitis

inflammation of the bronchi, which carry air to and from the lungs; can be either acute or chronic

bronchitis causes

viruses (acute bronchitis), cigarette smoke (chronic bronchitis)

bronchitis symptoms

cough, production of mucus/sputum (can be clear, white, yellowish-gray or green in color — rarely, it may be streaked with blood), fatigue, shortness of breath, slight fever and chills, chest discomfort