respiratory system

list the passage of air in order to reach the alveoli

mouth and nose, pharynx, epiglottis, larynx, trachea, bronchi, bronchioles, alveoli

mouth and nose

air enters and small hairs in the nose filter the air and mucus warms and moistens the air

pharynx

 tube at the back of the nasal cavities and mouth and is passageway for air and food

epiglottis

flap of cartilage that covers the opening to air passage

trachea

air passageway made of cartilage which contain cilia and mucus to trap particles

larynx

upper end of trachea that contains the vocal cords

bronchi

two branches that lead from trachea to the lungs

bronchioles

smaller tubes into the lungs

alveoli

clusters of tiny air sacs surrounded by capillaries

gas exchange in the lungs

1. Oxygen crosses two cells: alveolus cell and capillary wall cell and enters the blood

2. Carbon dioxide crosses capillary wall cell and  alveolus cell and enters the alveoli

3. Concentration gradient of these two gases will ensure diffusion of each gas in the correct direction

type I and II pneumocytes

type I

• very thin, large membrane surface area, if damaged cannot be replaced by mitosis

type II

• cuboidal, little membrane surface area, can be replaced by mitosis if damaged

label the alveoli and surrounding capillaries

a- fluid and surfactant

b- air

c- type 1 pneumocytes

d- erythrocytes

e- blood capillary

f- type 2 pneumocytes

define breathing

process of moving air into and out of the lungs. inverse relationship between pressure and volume. one increases, the other decreases

define ventilation

: repeated process of filling our lungs with air and then expelling that air     

define inspiration

inhaling, is the process of taking air into the lungs. used external intercostal muscles

define expiration

exhaling, passive process of expelling air from lungs. uses internal intercostal muscles

the steps involved with inspiration

1. Diaphragm contracts and external intercostal muscles and one set of abdominal muscles raise the rib cage: Increases the volume of the thoracic cavity 

2. Increased volume in chest cavity results in the pressure inside the cavity to decrease: leads to less pressure “pushing on” the passive lung tissue

3. Lung tissue increases its volume because there is less pressure exerted on it

4. Leads to a decrease in pressure inside the lungs: known as partial vacuum 

5. Air comes in through your open mouth or nasal passages to counter the partial vacuum within the lungs and fills the alveoli 

the steps involved with expiration

1. Diaphragm relaxes and rib cage goes down

2. Volume in chest cavity decreases and air pressure is greater so air rushes out

emphysema

the alveoli in the lungs are progressively destroyed. it can be prevented by not smoking and wearing a mask when working around dust or chemical fumes

lung cancer

cancerous growth in the lungs take over healthy tissues that were bronchioles and alveoli

caused by carcinogens entering the lung tissue and mutates into a cancerous growth

asthma

episodes of coughing, wheezing, chest tightness and difficulty breathing.

caused by airways thickening and bronchospasm magnifying and air flow being reduced.

chronic bronchitis

inhaled irritants can lead to an excessive production of mucus and obstruct airways. caused by smocking and air pollution

tuberculosis

infectious disease caused by bacteria. spread by coughing and enters the body through air and affects the lungs. symptoms are fevers, weight loss, racking cough, and coughing up blood.

the function and location of hemoglobin

protein molecule found within erythrocytes that carries most of the oxygen in the bloodstream

the number of oxygen molecules hemoglobin can carry

it can carry up to 4 oxygen molecules

describe the 3 ways that CO2 is transported in the blood

• Carbon dioxide dissolved in the blood plasma

• Carbon dioxide can bind to hemoglobin

• Carbon dioxide combines with water to form carbonic acid which breaks down into HCO₃^- and H+ by using the enzyme carbonic anhydrase inside the red blood cell

state the function of carbonic anhydrase

it is an enzyme in the cytoplasm of erythrocytes that catalyzes the reaction of CO2 and water to form carbonic acid

the process of how hydrogen carbonate ion is formed including the chloride shift

1. enzyme in the cytoplasm of erythrocytes that catalyzes the reaction of CO₂ and water to form carbonic acid

2. Carbonic acid then dissociates into H⁺ and hydrogen carbonate ion (HCO₃^-)

3. HCO₃^- exits cell through protein channel in erythrocyte membrane by facilitated diffusion

• One HCO₃^- moves out and one Cl^- moves in

• Chloride shift:  movement of ions to keep the charges balanced

what range does the pH of blood plasma need to stay within

pH of 7.35-7.45

explain the way blood buffers to maintain its pH

• H+ binds to hemoglobin

• H+ binds to plasma proteins

• Carbon dioxide is converted to HCO₃

Why does the blood require a buffering system to maintain its pH range during exercise?

Due to more H+ when exercising due to an increased production of CO2

Which part of the brain controls the rate of ventilation (breathing)?

It is controlled by the respiratory control center in the medulla oblongata

How does the respiratory system adjust during exercise to manage increased metabolism?

during exercise the rate of ventilation changes in response to the amount of CO₂ in the blood

how does air pressure change at higher altitudes and how this affects your breathing

air at higher altitudes is at a lower pressure . it affects your breathing because diffusion of oxygen across the alveoli into the bloodstream is less efficient and less oxygen enters the blood

the symptoms experienced at high altitudes

physical activity leads to immediate fatigue, vision problems, nausea, high pulse rate, difficulty in thinking clearly, severe altitude sickness

the ways your body can compensate at high altitudes

• Increasing ventilation rate and heart rate

• Increase in the capillaries in both the lungs and muscles