2 RESPIRATION, LUNGS + DIFFUSION Flashcards
Define diffusion
The random movement of particles from an area of high concentration to an area of low concentration
How does an increased temperature affect diffusion
Molecules have more kinetic energy so move faster - diffusion occurs faster
How does increasing concentration gradient affect diffusion
Large concentration gradient will make particles move from high to low quicker
How does increasing the surface area and surface area : volume ration affect diffusion
- Larger SA increases diffusion as particles can move over a larger area
- Small structures have large SA:V ratios, so diffusion occurs quicker
Function of the trachea
- Allows air into lungs
- Surrounded by C-shaped rings of cartilage to keep trachea open under pressure, and allow swallowing easier
Function of the bronchi
2 tubes that lead air to the lungs, that are also surrounded by cartilage rings
Function of the bronchi
2 tubes that lead air to the lungs, that are also surrounded by cartilage rings
Function of bronchioles
Branch of bronchi that carry air deep into the thorax
Function of alveoli
At the end of bronchiels. Carry out gas exchange
Function of pleural membrane
- Forms a layer between lungs and thorax walls
- Prevent lungs sticking to the thorax wall when they inflate and deflate
Function of ribs
Protect the organs in thorax
Function of intercoastal muscles
Connect ribs and control ventilation
Function of intercoastal muscles
Connect ribs and control ventilation
Function of diaphragm
Controls ventilation
Function of diaphragm
Controls ventilation
Describe what happens upon inhalation
- Diaphragm contracts, moving down and flattening
- Intercostal muscles contract, moving rib cage up and out
- Volume of thorax to increase, and pressure to fall
- Air pressure is less than atmospheric, so air moves in
Describe what happens upon exhalation
- Diaphragm relaxes, moving up and doming
- Intercostal muscles relax, moving rib cage down and in
- Volume of thorax to decrease and air pressure to rise
- Air pressure is more than atmospheric pressure, so air moves out lungs
How is Co2 carried around the body
Dissolved in plasma of blood
How are capillaries large surface area efficent for gas exchange
Large surface area, which increases rate of diffusion of oxygen in, and carbon dioxide out
How does each alveolus being currounded by a network of capillareis make it effecient for gas exchange
- Constantly carrry deoxygenated blood to alveolus and oxygenated blood away
- Maintains high concentration gradient and speeds up diffusion
How do the alveoli only being one cell thick, being right next to capillary walls (and them being only one cell thick), increase gas exhange
- Gases only need to move a very small distance, speeding up diffusion
High Co2 levels in hydrocarbonate indicator
Yellow
High Co2 levels in hydrocarbonate indicator
Yellow
Atmospheric Co2 levels in hydrocarbonate indicator
Red
Low Co2 levels in hydrocarbonate indicator
Purple
Why does breating rate increase during exercise
- Co2 is excreted more rapidly
- Oxygen can diffuse into blood at higher rate
- Heart rate increases, and supplies more oxygen to muscles for aerobic respiration
- Extra oxygen is supplied to oxidise lactic acid produced by muslces respiring anaerobically
Why is nicotine harmful
Highly addictive in tobacco
What biological effect do carcinogens in tobacco smoke have
Alter DNA and increase the risk of cancer
What biological effect do carcinogens in tobacco smoke have
Alter DNA and increase the risk of cancer
What are the biological effects of carbon monoxide when smoking
- Irreversibly binds to haemoglobin forming carboxyhaemoglobin
- Reduced amount of oxygen transported in blood
What are the biological effects of carbon monoxide when smoking (in pregnancy)
Baby gets less oxygen, and will weigh less at birth
What is the biological effect of smoking on cilia
- Goblet cells (on lining of trachea and bronchi) produce mucas trapping dust and pathogens, which is then moved by cilia up the airway
- Chemicals in tobacco smoke destroy cilia reducing there number and mucas production increases
- Mucas cannot be moved away so builds up
- Causes smokers cough, infection and bronchitis
How does smoking effect the alveoli
The walls break down and fuse together forming larger irregualr air spaces - decreases SA so less gas exchange (enphysema)
How does smoking increase the risk of CHD
Increases blood pressure, and risk of fatty deposits forming
How is energy released from respiration
As ATP
Aerobic respiration word equation
Glucose + Oxygen –> Carbon Dioxide + Water
Aerobic respiration word equation
Glucose + Oxygen –> Carbon Dioxide + Water
Difference in respiration - glucose
Aerobic fully oxidises it, therfore releasing lots of ATP, whereas anaerobic it doesn’t so less ATP is released
Animal anaerobic respiration equation
Glucose –> Lactic Acid
Plant and fungi anaerobic respiration equation
Glucose –> Ethanol + Carbon Dioxide
When does anaerobic respiration occur
Conditions of no oxygen
Where is lactic acid oxidised
Liver
How do the alveoli only being one cell thick, being right next to capillary walls (and them being only one cell thick), increase gas exhange
- Gases only need to move a very small distance, speeding up diffusion
Describe what happens upon inhalation
- Diaphragm contracts, moving down and flattening
- Intercostal muscles contract, moving rib cage up and out
- Volume of thorax to increase, and pressure to fall
- Air pressure is less than atmospheric, so air moves in
