Science (Bio, Chem, Physics) Flashcards
These features allows what
All gas exchange surfaces have features in common
These features allow the maximum amount of gases to be exchanged across the surface in the smallest amount of time
Features on breathing organism
Large surface area to allow faster diffusion of gases across the surface
Thin walls to ensure diffusion distances remain short
Good ventilation with air so that diffusion gradients can be maintained
Good blood supply to maintain a high concentration gradient so diffusion occurs faster
The passages down to the lungs are lined with
ciliated epithelial cells
Function of Cilia
have tiny hairs on the end of them that beat and push mucus up the passages towards the nose and throat where it can be removed
Mucus is made by
by special mucus-producing cells called goblet cells
Mucus function
traps particles, pathogens like bacteria or viruses, and dust and prevents them getting into the lungs and damaging the cells there
Cilia and Mucus functions
Mucus traps particles, dust and pathogens and cilia beat and push it up and away from the lungs
The function of the cartilage
The function of the cartilage is to support the airways and keep them open during breathing
What if the cartilage isn’t present?
If they were not present then the sides could collapse inwards when the air pressure inside the tubes drops
When you breathe in, air reaches millions of tiny structures in the lungs called alveoli through this pathway:
nose/mouth → larynx → trachea → bronchi → bronchioles → alveoli
Intercostal muscles function
two sets of intercostal muscles; one to pull the rib cage up and another set to pull it down
Intercostal muscles located at
One set of intercostal muscles is found on the outside of the ribcage (the external intercostal muscles)
The other set is found on the inside of the rib cage (the internal intercostal muscles)
detecting chemical changes
a. A colour change
b. A gas is given off
c. Heat is produced
d. A change in pH
d. A precipitate is formed
