Exchange And Transport Systems Flashcards
Tidal volume is
The volume of air in each breath
Ventilation rate is
The number of breaths per minute
Forced expiratory volume
The maximum volume of air that can be breathed out in one second
Forced vital capacity
The maximum volume of air it is possible to breathe forcefully out of the lungs after a really deep breath in
How is TB caused
Bacteria
How does TB affect the body
When someone’s becomes infected with tuberculosis bacteria, immune system cells build a wall around the bacteria in the lungs. This forms small, hard lumps known as tubercles. Infected tissue within the tubercles died and the gaseous exchange surface is damaged, so tidal volume is decreased.
Symptoms of TB
Persistent cough Coughing up blood Mucus Chest pains Shortness of breath (increased ventilation rate) Fatigue
What is fibrosis
The formation of scar tissue in the lungs
Structure of gills
Water containing oxygen enters the fish through its mouth and passes through the gills. Each gill js made of lots of thin plates called gill filaments which give a large surface area for exchange of gases. The gill filaments are covered in lots of lamallae which increase the surface area even more. The lamallae have lots of blood capillaries and a thin surface layer of cells to speed of diffusion between water and the blood
Counter current system
In the gills of a fish, blood flows through the lamellae in one direction and water flows over them in the opposite direction. This is called a counter current system. The counter current system means that water with a high oxygen concentration always flows next to blood with a lower concentration of oxygen. This in turn means that a concentration gradient between water and blood is maintained over the whole length of the gill. So as much oxygen diffuses from the water into the blood as possible
Main gas exchange surface in a lead
Mesophyll layer
Gas exchange in insects
Air moves into the trachea from the spiracles. Oxygen travels down the concentration gradient towards cells. The trachea branch off into tracheoles which go into individual cells. Oxygen diffuses directly into resourcing cells. Carbon dioxide moves down the concentration gradient towards the spiracles where it’s released into the atmosphere. Insects use rhythmic abdominal movements to move air in and out of the spiracles
Lung structure
Trachea
Bronchus
Bronchioles
Alveoli
What happens during inspiration
External intercostal and diaphragm contract. Ribcage moves up and out. Diaphragm flattens Increases volume in thorax Lung pressure decreases Air is drawn in
What happens in expiration
External intercostal muscles and diaphragm relax Ribcage moves in and down Diaphragm curves upwards Volume in thorax decreases Air pressure in thorax increases Air is forced out
Movement of oxygen through the lungs
Trachea Bronchi Bronchioles Alveoli Alveolar epithelium Capillary endothelium Blood
How is fibrosis caused
Infection or exposure to dust
How does fibrosis affect the lungs
Scar tissue is thick and less elastic than normal long tissue so the lungs cannot expand as much - they can’t hold as much air. Tidal volume reduce and forced vital capacity is reduced
Symptoms of fibrosis
Faster ventilation rate Shortness of breath Dry couch Chest pain Fatigue Weakness
Asthma is caused by
Allergic reaction
What happens to the lungs during asthma attacks
Smooth muscle lining the bronchioles contract and large amount of mucus is produced. Causes constriction of the airways. Oxygen in lungs is reduced so reduced forces expiratory volume
Asthma symptoms
Wheezing
Tight chest
Shortness of breath