Tag: human respiratory system

Questions Related to human respiratory system

Descending aorta and pulmonary trunks are

  1. Muscular arteries

  2. Medium arteries

  3. Elastic arteries

  4. Arterioles major


Correct Option: C
Explanation:

Descending aorta and pulmonary trunks are elastic arteries and are quite distensible.

The respiratory centers, which control inspiration and expiration, are located in?

  1. Diencephalon

  2. Medulla oblongata

  3. Cerebellum

  4. Spinal cord


Correct Option: A

Air is breathed through

  1. Trachea $\rightarrow$ lungs $\rightarrow$ larynx $\rightarrow$ pharynx $\rightarrow$ alveoli

  2. Nose $\rightarrow$ larynx $\rightarrow$ pharynx $\rightarrow$ bronchus $\rightarrow$ alveoli $\rightarrow$ bronchioles

  3. Nostril $\rightarrow$ pharynx $\rightarrow$ larynx $\rightarrow$ trachea $\rightarrow$ bronchi $\rightarrow$ bronchioles $\rightarrow$ alveoli

  4. Nose $\rightarrow$ mouth $\rightarrow$ lungs


Correct Option: C
Explanation:

In humans respiratory system consists of respiratory tract (conducting zone) and lungs (exchange zone). The respiratory tract is the passage from external nostrils to lungs or a passage by which air enters into lungs. The respiratory passage starting from external nostrils is nasal chamber --> internal nares --> nasopharynx -->pharynx --> glottis --> larynx --> trachea --> bronchial tree (bronchi and bronchioles) --> alveoli.

In fever breathing rate

  1. Increase

  2. Decrease

  3. Stop

  4. None of the above


Correct Option: A
Explanation:

Normal body temperature is around $37^0$C. Fever happens when the body's temperature is higher than normal because of an infection. Fever causes an increase in the heart rate, breathing rate and blood circulation to the skin. This is how the body tries to reduce the heat caused by fever. 

Which energy is consumed in breathing?

  1. Mechanical

  2. Chemical

  3. Bioelectricity

  4. Physical energy


Correct Option: B
Explanation:

In breathing or cellular respiration, a set of metabolic reactions and processes take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products. The reactions involved in respiration are catabolic reactions, which break large molecules into smaller ones, releasing energy. Respiration is one of the key ways a cell gains useful energy to fuel cellular activity. Cellular respiration is considered an exothermic redox reaction which releases heat. The overall reaction occurs in a series of biochemical steps, most of which are redox reactions themselves.

Therefore, the correct answer is option B.

Breathing by ribs is more pronounced in

  1. Male

  2. Female

  3. Pregnant female

  4. None of the above


Correct Option: C
Explanation:

During the third trimester, as the uterus continues to grow, it puts pressure on the internal organs and the diaphragm, which in turns restricts the amount of room available for lungs and leads to shortness of breath. So breathing by ribs is more pronounced during pregnancy, as it slightly raises the rib cage and temporarily gives more breathing space to lungs making breathing little easier.

Amount of $O _2$ normally carried by 100 ml of pure blood, is

  1. 40 ml

  2. 10 ml

  3. 20 ml

  4. 30 ml


Correct Option: C
Explanation:
Oxygen is carried in the blood either in dissolved form or in association with  hemoglobin.
However, to calculate the concentration of oxygen transported in the blood, one need to understand the amount of oxygen carried by each gram of hemoglobin. In a saturated condition, one gram of hemoglobin  carries 1.34 ml of oxygen. Normally 100 ml of blood has  around 15 gm of hemoglobin in it.
Thus, the amount of oxygen carried in 100 ml of pure blood can be calculated as 15 * 1.34 ml = 20 ml

Cutaneous respiration takes place through

  1. Gills

  2. Lungs

  3. Skin

  4. Cell membrane


Correct Option: C
Explanation:

Cutaneous respiration or cutaneous gas exchange, is a form of respiration in which gas exchange occurs across the skin or outer integument of an organism rather than gills or lungs. Cutaneous respiration may be the sole method of gas exchange, or may accompany other forms, such as ventilation. Cutaneous respiration occurs in a wide variety of organisms, including insects, amphibians, fish, sea snakes, turtles, and to a lesser extent in mammals, including humans. 

Therefore, the correct answer is option C.

Which of the following features do all gas exchange have in common?

  1. They are enclosed within ribs.

  2. They are maintained at constant temperature.

  3. The exchange surfaces are moist.

  4. They are exposed to air.


Correct Option: C
Explanation:

Gas exchange and respiration are essential if cells are to stay active, grow and divide. All the structures for gas exchange have common as follows:

  • They have a large surface area relative to the volume of the organism. 
  • They are thin and so have a short diffusion pathway. 
  • They have a moist surface where gases can dissolve first before they diffuse in or out. 
  • They are able to maintain the diffusion gradient down which the gases can diffuse.
Therefore, the correct answer is option C.

Full name of NADP is

  1. Nicotinamide dinucleotide phosphate

  2. Nicotine adenine dinucleotide phosphate

  3. Nicotinamide adenine dinucleotide phosphate

  4. None of the above


Correct Option: C
Explanation:

Nicotinamide adenine dinucleotide phosphate, abbreviated NADP is a cofactor used in anabolic reactions, such as lipid and nucleic acid synthesis, which require NADPH as a reducing agent.