Respiration in Humans

Q. The trachea do not collapse even when there is not much air in the lungs because they are:

1. made of smooth involuntary muscles.
2. supported by valves.
3. supported by rings of cartilage.
4. supported by larynx.

Q.

Question 56
Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms?

Q.

The correct sequence of anaerobic reactions in yeast is

1. $\mathrm{Glucose}\stackrel{\mathrm{cytoplasm}}{\to }\mathrm{Pyruvate}\stackrel{\mathrm{mitochondria}}{\to }\mathrm{Ethanol}+\mathrm{Carbon}\mathrm{dioxide}$

2. $\mathrm{Glucose}\stackrel{\mathrm{cytoplasm}}{\to }\mathrm{Pyruvate}\stackrel{\mathrm{cytoplasm}}{\to }\mathrm{Lactic}\mathrm{acid}.$

3. $\mathrm{Glucose}\stackrel{\mathrm{cytoplasm}}{\to }\mathrm{Pyruvate}\stackrel{\mathrm{mitochondria}}{\to }\mathrm{Lactic}\mathrm{acid}.$

4. $\mathrm{Glucose}\stackrel{\mathrm{cytoplasm}}{\to }\mathrm{Pyruvate}\stackrel{\mathrm{cytoplasm}}{\to }\mathrm{Ethanol}+\mathrm{carbon}\mathrm{dioxide}.$

Q.

When we blow exhaled air into the solution of lime water, it turns milky. What actually happens in the solution?

Q.

Why do cells need oxygen?

Q.

If epiglottis is not present what happens to passage of food and air

Q.

What are the by-products of respiration?

Q. What will happen to the rate of photosynthesis in a plant under the following circumstances ?
(i) cloudy day in morning but bright sunshine in the afternoon.
(ii) no rainfall in the area for a considerable time.
(iii) gathering of dust on the leaves.

Q.

Give two examples where anaerobic respiration takes place.

Q. What type of respiration takes place in human muscles during vigorous physical exercise? Give reason for your answer.

Q.

Write the overall equation for anaerobic respiration in yeast and muscle cells.

Q.

Write the events that takes place during inhalation and exhalation.

Q.

Explain why, it is dangerous to inhale air containing carbon monoxide.

Q. Fill in the blanks :​​
(ii) is a common opening of a food pipe and windpipe.

Q.

Answer in one word:
The process of converting food into simpler and soluble form.

Q. (b) (i) Which simple food is prepared first in the process of photosynthesis ?
(ii) Name the food which gets stored in plant leaves.

Q.

The breathing rate in humans under normal condition is

1. 16 - 18 times

2. 20 - 25 times

3. 39 - 32 times

4. 18 - 20 times

Q. Answer the following in "Yes" or "No".

(ii) Photosynthesis is the only biological process that releases oxygen into the air.
Yes
No

Q.

Are the Uvulla and the epiglottis the same thing? Or do they do the same work? If not, then what are their respective functions!

Q.

Question 14
Which of the following statement(s) is (are) true about respiration?

(i) During inhalation, ribs move inward and the diaphragm is raised.
(ii) In the alveoli, exchange of gases takes place i.e., oxygen from alveolar air diffuses into blood and carbon dioxide from the blood into the alveolar air.
(iii) Haemoglobin has a greater affinity for carbon dioxide than oxygen.
(iv) Alveoli increase surface area for exchange of gases.

(a) (i) and (iv)
(b) (ii) and(iii)
(c) (i) and (iii)
(d) (ii) and (iv)

Q. What happens to the diaphragm during exhalation?

1. Relaxes
2. Flattens
3. Contracts
4. No change

Q.

Question 77
Draw the diagram of the alimentary canal of man and label the following parts.
Mouth, Oesophagus, Stomach, Intestine

Q. The pharynx opens into the larynx by a slit-like aperture called _______.

1. bronchus
2. glottis
3. trachea
4. epiglottis

Q.

Question 4
How are the lungs designed in human beings to maximise the area for exchange of gases?

Q.

Smelling salts have ammonium carbonate as their chief constituent. When sniffed, the salts react with the basic lining of the nostrils to release ${\mathrm{NH}}_3$ gas, which irritates membranes, thereby causing the person to inhale deeply resulting in improved alertness.

1. Write the balanced equation for ${\mathrm{NH}}_3$ evolution inside the nostrils.
2. Unconscious boxer can be brought back to their senses using smelling salts. Do you agree?

Q. Which of the following is true for inspiration?

1. Thoracic chamber volume increases
2. Diaphragm contracts
3. Pulmonary volume increases
4. All of these

Q. Which of the following events does not occur during exhalation in human beings?

1. The intercostal muscles pull the ribs inwardly.
2. The volume of thoracic cavity increases.
3. High pressure area is created inside the thoracic cavity.
4. Diaphragm becomes dome-shaped.

Q. Air always moves from a region of low pressure to high pressure.

1. True
2. False

Q. Opening to the trachea is covered by a small flap of tissues termed as the ____.

1. tongue
2. larynx
3. diaphragm
4. epiglottis

Q. Arrange the following activities in the order of increasing breathing rates and give reason for your answer.

(i) Sleeping
(ii) Watching T.V.
(iii) Brisk walk
(iv) Cycling