LO2 Flashcards
what does the respiratory system consist of?
•larynx
•trachea
•bronchi
•bronchioles
•alveoli
•diaphragm
•intercostal muscles
•pleural membrane
what is the function of the larynx?
connects to the back of the nose and the trachea, forming an air passage to the lungs
allows us to produce vocal sounds
what is the function of the trachea?
known as the windpipe
it starts are the back of the throat (pharynx) and divides into 2 bronchi
has C-shaped rings of cartilage in its structure to prevent it collapsing so that an open air passage is maintained even when lying down
made of bone, cartilage rings joined by ligaments
produces mucus
what is the function of the bronchi?
made of bone to help the trachea stay strong and continue transporting oxygen even when lying down
what is the function of the bronchioles?
branch off the bronchi
to deliver air to a diffuse network of alveoli in the lungs
what is the function of alveoli?
sacs found in clusters at the end of the bronchioles
microscopic
each alveolus is surrounded by a capillary network where gaseous exchange of Oxygen and Carbon dioxide takes place through the alveolar membrane
what is the function of the diaphragm?
thin dome-shaped muscle
anchored to the lower ribs that separate the chest from the abdomen
helps with inspiration and expiration
flattens - inspiration
lifts back into dome shape - expiration
what is the function of the intercostal muscles?
muscles found between ribs
help the diaphragm with expanding and compressing
pull the rib cage upwards and outwards and diaphragm flattens inwards - inspiration
opposite for expiration
what is the function of the pleural membrane?
2 layers of thin membrane that covers the outside of the lungs and lines the inside of the chest wall
film of liquid between layers makes it moist and slippery which lubricates the surface to allow layers to slide over each other and the lungs to move easily within the chest cavity
reduces friction between lungs and chest wall when breathing
what happens during inspiration?
it is a process that required energy
diaphragm and intercostal muscles contract
ribs move up and out
diaphragm flattens
volume in thorax increases and pressure decreases
air rushes into lungs and down pressure gradient
elastic tissue of alveoli stretches
lungs inflate
what happens during expiration?
the diaphragm lifts back into dome shape
intercostal muscles pull the ribcage inwards and downwards.
forces carbon dioxide out of the lungs and they deflate.
What is gaseous exchange?
A process that involves the exchange of oxygen and carbon dioxide between capillaries and alveoli
Structure of alveoli
The walls of the alveoli are very thin (one cell thick) for a shorter diffusion distance of exchanging carbon dioxide and oxygen.
Each alveoli is surrounded by capillaries to make gaseous exchange easier
In groups like bunches of grapes which increases their surface area to allow the maximum diffusion - makes process more efficient
Diffusion gradients
Diffusion is the movement of gas molecules from an area of high concentration to an area of low concentration.
Particles diffuse down a concentration gradient
The capillaries have a lower concentration of oxygen than the alveoli. This means the oxygen diffuses from the alveoli into the bloodstream.
What is cellular respiration?
A complex set of chemical reactions and processes that take place in the mitochondria to convert biochemical energy from nutrients into ATP and then release waste products
role of glucose
serves as a primary reactant in aerobic respiration.
role of oxygen
required for aerobic respiration
the electron transport chain takes place in the mitochondria if oxygen is available.
function of ATP
ATP is produced and used to provide energy for cell activities such as muscle contraction.
Aerobic respiration
- requires oxygen
- glycolysis takes place in cytoplasm
- electron transfer chain takes place in the mitochondria
- Pyruvate enters the Krebs Cycle
- Glucose and oxygen react to produce water and carbon dioxide as waste products
- Produces more ATP
Anaerobic respiration
- lack of oxygen needed
- also used glucose
- Produces less ATP
- Converts pyruvate into lactate
- Takes place in cytoplasm
- Lactic acid can build up in muscles and is toxic to the body. Anaerobic respiration only occurs for a short period until oxygen becomes available and lactic acid is then broken down.
*lactic acid is a waste product - occurs in muscles during exercise
*less ATP produced because the pyruvate is converted to lactate