Physiology - lecture 1 Flashcards
(43 cards)
What are the functions of the respiratory system?
Gas exchange, acid base balance, protection from infection and communication via speech
How is it involved in gas exchange?
Add O2 to blood from air and removes CO2 from blood into air
How is it involved in acid base balance?
Maintains pH of extracellular fluid
How is it involved in protection from infection?
Upper respiratory tract is the first point of contact so pathogens can get in easily so it is lined with macrophages and lymphocytes to scan the air we breathe.
Mucus traps any particles and prevents it from going further in and damaging delicate parts of the tract like the alveoli
The cilia helps beat mucus up form the delicate tissue
How is it involved in communication via speech?
Air moves across vocal chords on expiration
Why is oxygen needed?
To produce energy (ATP) to power cells
How is oxygen used as energy?
oxygen is burned to release energy and produces Co2 as a waste product
What is the respiratory system responsible for?
Acquiring O2 and removing CO2
What is external respiration, what does it require and where does it occur?
Movement of gases between the air and body cells. It requires the Respiratory system and the CVS integrating. It takes place outside of cells.
what is systemic circulation?
Delivers O2 from blood to cells/tissue and moves Co2 from cells to blood. Arterial blood is rich in O2 and venous blood is rich in CO2
What is pulmonary circulation?
Delivers CO2 to lungs an picks up O2 from them. Pulmonary artery is the only artery in the body which carries deoxygenated blood and the pulmonary vein is the only one to carry oxygenated blood.
Only goes form heart to lungs and back again to heart
What does an inc energy demand of muscles lead to in the respiratory system?
An increase in rate and depth of breathing which speeds up:-
substrate (O2) acquisition
waste disposal (CO2)
What does an inc energy demand of muscles lead to in the cardiovascular system?
An increase in heart rate and force of contraction which speeds up:-
substrate delivery to muscle via the blood
waste removal via blood (CO2)
where does gas exchange occur in the respiratory and cardiovascular systems?
Resp- alveoli
CVS - capillaries
What are the average volumes exchanged per minute for O2 and CO2?
O2 - 250ml (consumed)
CO2 - 200ml (produced)
this increases during exercise
What is the average breathing rate at 1) rest and 2) at maximum exercise for adults?
1) rest - 10-20 breaths per minute
2) exercise - 40-45
Which has less resistance to airflow mouth or nose?
Mouth
Why is the nose the preferred way of breathing? (rather than mouth)
mouth is uncomfortable as mouth begins to go very dry
Nose warms and moisten up the air which helps maintain core body temperature without causing the body to work harder and also prevents cold air from hitting he lungs
What is contained in the upper respiratory tract?
Nasal cavity, pharynx, tongue, vocal chords,oesophagus and larynx
What is in the lower respiratory tract?
trachea, left lung, left bronchus, right lung, right bronchus and diaphragm
How do the left and right bronchi compare in shape?
The right main bronchus s more vertical as well as wider than the left - causes foreign bodies to be lodged there as it has least resistance
What is patency?
Airways are open and unobstructed
How is potency maintained?
C-shaped rings of cartilage in the semi-rigid tubes
How is potency maintained in the bronchiole as it has no cartilage?
By physical forces in the thorax
