Unit E - respiratory system Flashcards
What parts of the body are used for breathing
The diaphragm (which pushes up) and intercoastal muscles
What does breathing supply the body with
Supplies the body with oxygen so that ATP can be formed by cellular respiration
What is respiration
The process by which oxygen is obtained from the environment and delivered to the cells
What is breathing
The process that brings oxygen into the lungs and expels carbon dioxide
How many types of respiration are there and what are they
Two types: internal respiration (occurs in the lungs) and external respiration (Occurs within the body)
What is the tongue
What is the pharynx
What is the larynx
Part of the oral cavity
Throat; collect air from mouth and nose and passes it to the trachea
Voicebox; contains the vocal chords
What is the epiglottis
Small flap of tissue that guards the entrance to the trachea; closes when food is swallowed
What is the trachea
Windpipe; passage leading from pharynx to lungs
What is the cilia
Very small hairlike structures that moves mucus containing dust, debris, etc. up into the throat where it can be removed or swallowed
What are bronchi
What are bronchiole
What are Alveoli
Main branches of the trachea; tubes that lead into the lungs
Smallest subdivisions of the bronchi
Small air sacs where gas exchange occurs
What are Capillaries
Microscopic blood vessels that are embedded in the walls of the alveoli; site of gas exchange
What is the pleural membrane
What is pleural space
Thin membrane that surrounds the outer surface of the lungs
Space between the membrane surrounding the lungs, and lines the inner wall of the chest
What is the diaphragm
What are ribs
Strong wall of muscle separating the chest cavity from the abdominal cavity
Bones that support and protect the chest cavity; move to a limited degree and help the lungs expand and contract
Describe the path of air
Nasal activity, then pharynx, then larynx, then trachea, then bronchi, then bronchioles, then alveoli
What happens to air when it enters through the nasal cavity?
Air is warmed, moistened, And cleaned
Hairs filter and trap dust, mucus traps particles
What is the trachea protected by
What is the trachea covered with
What else does the trachea also contain
Trachea is protected by the epiglottis
Covered with cilia
Also contains mucus which traps debris
What are bronchioles composed of
Smooth muscles which can decrease in diameter
What are alveoli covered in
Capillaries
What happens to air after the alveoli
The pulmonary vein transports gas in the blood to the heart
Why does pressure in your chest vary
Because of the movement of your thoracic cavity
What happens to pressure when your thoracic cavity expands or compresses
Expands: pressure drops
Compresses: pressure rises
Gases move from a high area pressure to an area of low pressure
Why do inhaling and exhaling occur
Because of the differences between atmospheric pressure and pleural pressure
What is inspiration? When does it occur
Inhaling
Occurs when the pressure inside the lungs is less than it is in the atmosphere
What is expiration? When does it occur
Exhaling
Occurs when the pressure inside the lungs is greater than it is in the atmosphere
What is the diaphragm
A dome shaped sheet of muscle that separates the thoracic cavity from the abdominal cavity
What causes pressure changes in the chest
The intercostal muscles and diaphragm contracting and relaxing
Describe the process of inspiration
The diaphragm contracts and moves down
The intercostal muscles contract and move ribs up and out
The chest cavity become bigger and as a result, pleural pressure is less than atmospheric pressure
Air moves in
Describe the process of expiration
Diaphragm relaxes and moves up
Intercostal muscles relax and move ribs down and in
Chest cavity is smaller as a result of pleural pressure being higher than atmospheric pressure
Air moves out
What does Dalton’s law of pressure state?
each gas in a mixture exerts its own pressure independently of all other gases in the mixture.
Why does oxygen diffuse in (rather than out?)
Very high outside (atmosphere) High in alveoli Medium in blood Low in tissues Therefore O2 diffuses IN
Why does carbon dioxide diffuse out
Very high in tissues High in blood Medium in alveoli Low outside (atmosphere) Therefore CO2diffuses OUT
Describe the process of oxygen exchange
- diffuses into blood through capillaries in the alveoli
- combines with hemoglobin on red blood cells to form oxyhemoglobin
- diffuses into cells (used in cellular respiration)
- Or it dissolves in plasma
Describe the process of carbon dioxide exchange
Diffuses out of cells and into blood, where it will either:
combine with hemoglobin to form carbaminohemoglobin or dissolve in plasma, combine with water, and form carbonic acid.
then, it diffuses out of blood through capillaries
What do carbon dioxide and oxygen transport rely on?
Hemoglobin
What is hemoglobin
What does it consist of?
Is a molecule on the surface of RBCs
It consists of polypeptides that are composed of heme, and globin
What is heme? What is globin?
Heme: is the iron-containing pigment… oxygen or carbon dioxide binds to this
Globin: is the protein component
Describe the process of oxygen transport
In the lungs, oxygen attaches itself to hemoglobin to form oxyhemoglobin
Oxygen travels as oxyhemoglobin to the capillaries
At the capillaries, hydrogen ions dislodge oxygen
Oxygen diffuses into the extra cellular space and then into the cells
How many methods of carbon dioxide transport are there? What are they?
Two methods
- It can combine with hemoglobin
- Dissolve in the plasma
Describe how carbon dioxide is transported by combining with hemoglobin
27% of carbon dioxide combines with hemoglobin on the red blood cells to form carbaminohemoglobin
It is then transported to the lungs
Describe how carbon dioxide is transported by dissolving in plasma
64% of carbon dioxide combines with the water in plasma to form carbonic acid
CO2 + H2O = H2CO3
Carbonic acid disassociates to form a hydrogen ion and bicarbonate ion
Bicarbonate ions are transported to the lungs in the plasma
Hydrogen ions dislodge oxygen from hemoglobin
Hydrogen ions then combines with hemoglobin, forming reduced hemoglobin which returns to the lungs in venous blood
In the blood, the reduced hemoglobin acts as a buffer
At the lungs, hydrogen dislodge is from hemoglobin and combines with bicarbonate ions to form water and carbon dioxide
Carbon dioxide diffuses from the capillaries in the alveoli into the lungs and is exhaled
What do carbonic acid to do to the blood? What about its stability?
Lowers the pH of the blood
Unstable and disassociate to form a hydrogen ion and bicarbonate ion
H2CO3 = HCO3- + H+
What is a buffer
A substance that is able to neutralize acids and bases
What is breathing regulated by
The medulla oblongata
What are factors that influence breathing rate
Carbon dioxide levels in blood
Stretching of lung tissue
Emotional state
Serious injury
How do chemicals in blood affect breathing rate
Receptors
What are receptors used for?
Used to detect changes in the environment
Where is the information gathered by receptors sent to?
Your central nervous system (brain and spinal cord)
What do chemoreceptors do
What types of chemoreceptors are there
Detect changes in chemicals in the blood
Carbon dioxide receptors and oxygen receptors (oxygen receptors use as a backup only)
Are carbon dioxide receptors sensitive or insensitive? What do they regulate and where are they located
Most sensitive receptors
Main regulators of breathing rate
Located in the medulla oblongata
How do carbon dioxide receptors work
CO2 dissolved in blood forms carbonic acid
High levels of carbonic acid stimulate receptors in the medulla oblongata
Medulla oblongata send signal to the intercoastal muscles and the diaphragm to increase breathing rate
One CO2 levels return to normal, chemoreceptors become inactive and breathing rate returns to normal
When are O2 receptors stimulated
Where are they located
Only stimulated when O2 levels drop and CO2 levels remain constant
Located in the carotid artery and aortic arteries
How do oxygen receptors work
If O2 levels are low, receptors send a signal to the medulla oblongata to stimulate the intercoastal muscles and the diaphragm to increase in breathing rate
What happens to breathing at high altitudes
What happens to breathing if you have asphyxiation
What happens to breathing if you have hypoxia
High altitudes – less O2 molecules, breathing increased
Asphyxiation – too much CO2, breathing increased
Hypoxia – not enough O2, no warning
How does the stretching of lung tissue affect breathing rate
Stretch receptors in pleura, bronchioles, and alveoli are stimulated
Nerve impulses sent to medulla oblongata
Breathing rate drops
How does emotional state affect breathing rate
Fear and pain increase in breathing rate due to the increased need for oxygen
How does an injury to the stomach affect breathing rates
Bronchitis: the narrowing of the bronchi or bronchioles due to inflammation of the mucous lining
Excess mucus is produced and tissues swell, which reduces the diameter of the bronchi or bronchioles
What is emphysema?
What is a cause?
Inflammation of the alveoli which causes air sucks to lose their elasticity, stretch, and then rupture
It becomes difficult to exhale. Air becomes trapped in the lungs. With less alveoli there is decreased oxygen levels
Cause: smoking
What is bronchial asthma
Inflammation of the bronchioles as a result of particulates in the air or allergens
The bronchioles constrict and a greater effort is required to exhale
CO2 pressure builds in the lungs
What does the cilia in your bronchioles do
Sweep debris away from your lungs… Protecting them from bacteria and pollutants
What do the chemicals in tobacco smoke do to cilia
Kill cells that contain cilia… More debris enters your lungs
What does the tar in tobacco smoke do to the cilia
Coats the cilia, disabling them from keeping degree from your lungs
What does the carbon monoxide smoke do to you
Starve cells of oxygen… They can’t make ATP
What does the cyanide in cigarettes do to you
Stops the electron transport chain… Prevents ATP being made… Without energy the cells die
What is total lung capacity (TLC)
Total air held in lungs
Approximately 5800 mL
What is tidal volume (TV)
Air entering and leaving during normal inhale and exhale
Approximately 500 mL
What is inspiratory reserve volume (IRV)
Additional air that can be taken into lungs
Approximately 3000 mL
What is expiatory reserve volume (ERV)
Extra air that can be expelled from lungs
Approximately 1100 mL
What is residual volume (RV)
There always left in your lungs (otherwise there would be no pressure in them and they wouldn’t inflate)
Approximately 1200 mL
What is vital capacity (VC)
TV + IRV + ERV (total lung capacity minus the residual volume)
Approximately 4600 mL
What are the dangers of carbon monoxide
Finds to hemoglobin faster than O2 and prevents O2 from binding
If no oxygen gets to the tissues, you die
How are muscles attached the skeleton
What kind of energy conversions go on in muscles
When is the work that muscles do done
What triggers contraction
Attached to the skeleton by tendons
Convert chemical energy into kinetic
Done when they shorten; during contraction
Contraction triggered by a nerve signal
What are antagonistic muscles
Muscles that have the opposite reaction
For example, when your bicep is flexed your tricep muscle is relaxed
What is a flexor
What is an extensor
The muscle that contracts to bend a joint
The muscle that must contract to straighten a joint
How many types of muscles are there and what are they
Three types of muscles
Smooth, cardiac, skeletal
Describe smooth muscle
Lines the digestive tract, uterus, and arteries
Does not fatigue easily
Contraction occurs without conscious
Describe cardiac muscle
Unique to the heart which is part of the cardiovascular system
Contraction is involuntary
Describe skeletal muscles
Used for locomotion
Contraction is voluntary
Attached to bone by tendons
Explain skeletal muscle structure
Muscle –> Muscle–fiber bundle -> Muscle fiber -> Myofibrils -> Myofilaments
What does each muscle fiber bundle consist of
Many muscle fibers that are surrounded by connective tissue
What do muscle fibers consist of
Myofibrils
What are myofibrils
Hundreds of thousands of centrical subunits
What are the cylindrical subunits of myofibrils made of?
Protein structures called myofilaments
What are myofilaments responsible for
Muscle contraction
How many types of microfilaments are there and what are they
Two types: actin and myosin
What is the sliding filament theory
Theory that provides a model that helps explain how muscles contract
How do myofilaments contract
Muscles cause movement by shortening
Actin filaments slides over the myosin filaments
What are the steps to muscle contraction (Using actin and myosin)
Head of myosin moves… Like flexing your wrist
Actin filaments is chemically bonded to myosin and gets pulled along with it when it flexes
Actin filaments then slides pass the myosin filament in the direction of the flex
This continues, each time requiring ATP to provide energy
ATP is needed to repositioned myosin head before each new flex
After contraction, Acton and myosin filament disengage and the muscle begins to relax
What causes muscle fatigue
Very little ATP can be stored in muscle tissue
What is creatine phosphate and what does it do
High-energy compound found in muscles that ensures that ATP supplies remain high
How does create time phosphate ensure ATP supplies remain high
Supplies a phosphate to adenosine diphosphate
What happens if the energy demand is higher during muscle contraction
Lactic acid fermentation results, Causing pain and the muscle eventually fails to contract
What is a muscle contraction caused by
What does the strength of a contraction depend on
Caused by a nerve impulse
Strength depends on the frequency of the stimulus
How does muscle contraction occur? (4steps)
- Nerve cells stimulates muscle cell
- Pause called the latent period
- Muscle contracts/shortens… actin slides over myosin
- Muscle begins to relax and then returns to its original size
What does the speed of your muscle contractions depend on
Myosin
How many forms of myosin are there and what are they
Three types: Type I, Type IIa, Type IIx
What type of muscle twitches does type I myosin cause
What does it do to ATP
Where is it found in greater abundance
Causes slow muscle twitches
Breaks down ATP slowly
Found in greater abundance in long-distance runners
What type of muscle twitches does type IIa and IIx myosin cause
What do they do to ATP
What type of respiration does it rely on
Where is it found in greater abundance
Causes faster twitch
Breaks down ATP faster… Are less efficient
Anaerobic respiration
Greater abundance in sprinters
What is tendonitis
Inflammation of tendons due to overuse or injury stretched tendons
What are some examples of injuries
Torn muscles/sprains, tendonitis, torn ligaments, joint dislocations
What is anthroscopic surgery
Needle is inserted into the knee, lens provides a picture of the damage within
Image is projected onto a screen
At the scope is fitted with an surgical tools that can snip away unhealthy tissue
