The Respiratory System Flashcards
1
Q
Why do we inhale oxygen and exhale carbon dioxide ?
A
Respiration takes place in every cell to supply them with energy. We use oxygen and produce carbon dioxide and water in the process of respiration.
2
Q
Introduction
A
- Pair of lungs are located in the chest(thorax) region known as the thoracic cavity
- Ribs and intercostal muscle surround the thoracic cavity
- Diaphragm muscles form at the bottom of the thoracic cavity
- Air moves in and out of the lungs by the contraction of these muscles
3
Q
Nose
A
- Air is inhaled in through the nose(nostrils)
- Nostrils are separated by a nasal septum(made of cartilage)
4
Q
Benefits of breathing through the nose
A
- Hair and Mucous filters air in the nose and traps dust/bacteria
- Air is moistened
- Air is warmed passing through the nose}Helps oxygen diffuse into the blood more easily
5
Q
Pharynx(known as the throat)
A
- Consists of the epiglottis and larynx
- The epiglottis closes the trachea(windpipe) when we swallow. This prevents food from entering the windpipe and lungs.
- The larynx(voice box) produces vibrations to create sound.
6
Q
Trachea, bronchi and bronchioles
A
- These parts are all made up of muscle and rings of cartilage.
NOTE: - The rings of cartilage prevent these tubes from collapsing.
- Trachea, bronchus and bronchiole are lined with mucous and tiny hairs(cilia).These trap dust ,bacteria or viruses.
- When we clear our throat it helps force mucous up and into the oesophagus
7
Q
Lungs
A
- Spongy material(can expand and contract in size)
- Gas exchange with blood stream occurs here (diffusion)
- The lungs are enclosed by pleura membranes (a double membrane that contains fluid)
- Pleural cavity reduces friction on the lungs as a person inhales and exhales
8
Q
Function of Aveoli
A
- To allow gas exchange
- At the end of each bronchiole you have an air sac called an alveoli (700 million)
9
Q
Adaptations of aveoli
A
- Large surface area for gas exchange as they are so numerous
- Thin walled for easier gas exchange
- Moist surfaces(helps with diffusion)
- Have a rich blood supply from surrounding capillaries
10
Q
Gas exchange
A
- Carbon dioxide and water diffuses out of the cell and into the blood
- The carbon dioxide and water then diffuse out of the blood and into the alveoli of the lungs
- Also, oxygen diffuses from the alveoli into the blood and then into the cells (from a high to low concentration)
11
Q
Name the structures at the end of the breathing tract that are involved in gas exchange ?
A
Alveoli
12
Q
Inhaled and exhaled air
A
%Oxygen: Inhaled 21 Exhaled 14
%Carbon dioxide: Inhaled 0.04 Exhaled 5.6
Water concentration: Inhaled Low Exhaled Haigh
13
Q
Breathing Disorders (Asthma)
A
- Symptoms: Wheezy and breathlessness
- Cause(external): Allergens that might be inhaled(pollen/house dust), stress or anxiety, exercise in cold air
- Cause(internal): Bronchioles become narrower
- Prevention: Avoiding allergens and preventative inhalers
- Treatment: Steroids inhaled
14
Q
Control of human breathing
A
- The levels of carbon dioxide in the blood is detected by the brain which controls breathing rate.
- Carbon dioxide is acidic when it dissolves in blood which lowers its pH
- The brain (medulla oblongata) detects this low pH and sends an electrical message to the diaphragm and intercostal muscles which causes us to breathe faster especially when we exercise.
- NOTE: It is the higher levels of CO2 in our blood (from exercise) and not low levels of oxygen that controls our breathing rate.
- NOTE: Carbon dioxide controls rate of gas exchange in both animals and plants
15
Q
Medulla oblongata
A
The medulla oblongata is the part of brain that controls breathing
