The document contains questions about the respiratory system and respiration. It asks about the differences between breathing through the nose versus the mouth, the muscles involved in inspiration and expiration, why blood in the lungs contains high CO2, and how oxygen levels change in the blood after it passes through active versus resting muscles. It also includes questions about lung volumes and air flow, the functions of different organ systems, labeling anatomy and processes, and identifying true and false statements about respiratory system functions and structures.

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RESPIRATORY SYSTEM AND RESPIRATION
1. Why do you think breathing through the nose is better than through the
mouth? Give reasons.
2. Which muscles are involved in the respiratory stages (inspiration and
expiration)?
3. Why does the blood that arrives in the lungs contain a high proportion of
CO2?
4. The air we inhale contains a certain amount of CO2, why does this gas not
pass to the capillary in the alveoli?
5. The following table shows the amount of oxygen (O2) found in 100ml of
blood: when the blood stream reaches the muscle and when it leaves it:
Resting muscle Active muscle
Bloodstream reaching 21 ml 21 ml
Bloodstream leaving 12 ml 3 ml
a. How does the blood change when passing through the muscle?
Why?
b. What are the differences between the resting and active muscle?
What are these differences due to?
c. Imagine the type of changes (in the same blood) if we measure the
carbon dioxide (CO2) amount, instead of the oxygen amount.
6. As an average, humans do 12 inspirations per minute. The mean volume of
air that we intake is 500 ml. Using this data, calculate the volume of air that
your lungs can move during one minute.
7. Remember we do about 12 inspirations per minute.
a. How many inspirations do you do a day?
b. What is the volume of air that has reached your lungs in one day?
c. Air contains 21% oxygen (O2) (in volume). Of this, only a quarter (¼)
is captured by blood in the alveoli. Using previous data, what is the
quantity of oxygen that your cells receive in a day? Would it be
different if you do intense physical effort such as sports?

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8. Complete the following table:
ORGAN SYSTEM FUNCTION
Pharynx
Nutrients absorption
Food digestion
Nostril
Phonation (talk)
Bile storage
Large intestine
Respiration movements
Salivary glands
Gas exchange
9. Complete the following sentences:
a. The process of pulmonary ventilation that permits air renovation in the
lungs is called.......................................
b. The process of air entrance in the lungs is called.................................
c. Respiratory and digestive systems present one organ in common
called ...............................
d. Oxygen-rich air arrives in the..........................that are covered by a
vast network of.............that facilitate the exchange of gases between
the air and the blood.
10.Discuss if the following statements are true or false:
a. The respiratory system captures oxygen from the air, which is then
used by cells.
b. Pylorus connects small intestine with large intestine.
c. Pulmonary ventilation is gas exchange.
d. Pancreas receives nutrients absorbed by the small intestine.
e. The respiratory system makes gas exchange between the blood and
the environment possible.