Gas exchange - humans Flashcards
(26 cards)
What is the function of the trachea
it carries air to and from the lungs
What are bronchi
they are two tubes that branch from the trachea into each lung
What are bronchioles
they are smaller branches of the bronchi within the lungs
What is the function of alveoli
they are tiny air sacs where gas exchange occurs
What is the diaphragm
a muscle that helps with breathing by contracting and relaxing
What is the function of the ribs
they protect the lungs and help with breathing movements
What is the pleural membrane
it surrounds the lungs and reduces friction during breathing
What happens during inhalation
the diaphragm contracts and the intercostal muscles contract
ribs move up and out
What happens during exhalation
the diaphragm relaxes and the ribs move down and in
What is the role of the cilia in the trachea
they trap and move particles and mucus out of the lungs
What are the ribs
they protect the lungs and heart and help with breathing movements
What are intercostal muscles
muscles between the ribs that help with breathing by moving the ribs
What is the larynx
also known as the voice box
What is the sternum
the breastbone that protects the heart and lungs
What is the thorax
the chest region that contains the lungs heart and other vital organs
What are alveoli
Tiny air sacs in the lungs where gas exchange occurs
How are the alveoli adapted for gas exchange (3)
Large SA
Short diffusion distance
Moist surface helps gases dissolve
What can smoking cause?
Diseases in lungs
Coronary heart disease
Cancer
What are the harmful chemicals in cigarettes?
nicotine
carbon monoxide
tar
What are the effects of nicotine?
Narrows blood vessels
Increases heart rate
Increases blood pressure
high blood pressure -> blood clots -> heart attack/stroke
What are the effects of carbon monoxide?
Binds irreversible to haemoglobin in red blood cells -> breathing rate/depth increase -> blood pumped faster -> blood pressure raised -> risk of coronary heart disease/stroke
What are the effects of tar?
Carcinogen
Contributes to COPD (chronic bronchitis + emphysema occur together)
What is chronic bronchitis?
Tar stimulates goblet cells and mucus glands to enlarge and produce more mucus -> mucus builds up, blocks smallest bronchioles -> damage to cilia -> no removal of mucus -> smoker’s cough
