Regulation of Respiration

Q. The part of the brain 'X' contains a special neural centre that moderates the cardiac function through ANS as well as regulates the respiratory rhythm according to the need of the body. Identify 'X'.

1. Pons
2. Hypothalamus
3. Cerebellum
4. Medulla oblongata

Q. Which of the following helps prevent the lungs from over expanding during inspiration?

1. Medullary centre
2. Pneumotaxic centre
3. Apneustic centre
4. None of the above

Q. The amount of radiation emitted by a body depends on its temperature.

1. False
2. True

Q. Oxygen has a major role in regulation of respiration.

1. True
2. False

Q. Match the following
$\begin{array}{cc}\text{1. Carotid Body}& \text{i) Lower part of pons}\\ \text{2. Pneumotaxic centre}& \text{ii) Superior part of pons}\\ \text{3. Apneustic centre}& \text{iii) Bifurcation of artery located in neck}\\ \text{4. Chemosensitive area}& \text{iv) Adjacent to rhythm centre}\end{array}$

1. 1-ii, 2-iii, 3-iv, 4-i
2. 1-iv, 2-iii 3-i, 4-ii
3. 1-iv, 2-ii, 3-i, 4-iii
4. 1-iii, 2-ii, 3-i, 4-iv

Q.

Which of the following is not possible when pneumotaxiccentre is sending a strong signal?

1. Decreased duration of inspiration

2. Complete filling of lungs

3. Decreased duration of expiration.

4. Increase in rate of breathing

Q. Which of the following leads to negligible or no stimulation of receptors located in the aortic arch and carotid artery?

1. High oxygen concentration
2. Low carbon dioxide concentration
3. Low pH
4. None of the above

Q. A body cools from ${60}^{\circ }\text{C}$ to ${50}^{\circ }\text{C}$ in $10$ minutes. If the room temperature is ${25}^{\circ }\text{C}$ and assuming that Newton's law of cooling holds good, the temperature of the body at the end of the next $10$ minutes will be:

1. ${38.5}^{\circ }\text{C}$
2. ${40}^{\circ }\text{C}$
3. ${37.5}^{\circ }\text{C}$
4. ${42.9}^{\circ }\text{C}$

Q. A solid sphere, a cube and a plate, are made of the same material and all have same mass. These are heated to a temperature ${100}^{\circ }\text{C}$ and then allowed to cool at the temperature of the room. Which of these will cool down first –

1. Cube
2. Plate
3. Sphere
4. All will cool down simultaneously

Q. All of the following situations are possible when pneumotoxic centre is sending a strong signal, except

1. Decrease in duration of expiration
2. Increase in rate of breathing
3. Complete filling of lungs
4. Decrease in duration of inspiration

Q. Where is the pneumotaxic centre located?

1. Medulla
2. Pons
3. Cerebrum
4. Cerebellum

Q.

Fill in the blanks:

The inspiratory and expiratory centres are present in the___(i)____. The Pneumotaxic and the Apneustic centres are present in the___(ii)___. The inspiratory system is basically responsible for___(iii).___ The expiratory system become activated during forced ___(iv)___.

1. i).$\to$Medulla ii).$\to$Pons iii).$\to$Inspiration) iv). $\to$Expiration.

2. i).$\to$Pons ii).$\to$Medulla iii).$\to$Expiration iv).$\to$ Inspiration.

3. i).$\to$Medulla ii).$\to$ Pons iii).$\to$ Inspiration iv). $\to$Inspiration.

4. i).$\to$Medulla ii).$\to$ Pons iii).$\to$Expiration iv).$\to$ Expiration

Q. When $C{O}_2$ concentration decreases, the rhythm centre of the brain is signalled to make the necessary changes.

1. False
2. True

Q.

The apneusticcentre increases the depth of___(i)____ by acting directly on the ___(ii)____ centre. The pneumotaxiccentre inhibits the ___(iii)____ centre, thus increasing the respiratory rate i.e the duration of inspiration and expiration___(iv)____.

1. i).➡Expiration ii).➡Expiratory, iii).➡Inspiratory iv).➡Increases.

2. i).➡Inspiration ii).➡Inspiratory, iii).➡Expiratory iv).➡Decreases.

3. i).➡Expiratory ii).➡Inspiratory , iii).➡Expiration iv).➡Increases.

4. i).➡Inspiration ii).➡Inspiratory, iii).➡Expiration iv).➡Decreases.

Q.

The apneustic centre increases the depth of___(i)____ by acting directly on the ___(ii)____ centre. The pneumotaxic centre inhibits the ___(iii)____ centre, thus increasing the respiratory rate i.e the duration of inspiration and expiration___(iv)____.

1. i) $\to$ Expiration, ii) $\to$ Expiratory, iii) $\to$ Inspiratory, iv) $\to$ Increases

2. i) $\to$ Inspiration, ii) $\to$ Inspiratory, iii) $\to$ Expiration, iv) $\to$ Decreases

3. i) $\to$ Inspiration, ii) $\to$ Inspiratory, iii) $\to$ Expiratory, iv) $\to$ Decreases

4. i) $\to$ Expiratory, ii) $\to$ Inspiratory, iii) $\to$ Expiration, iv) $\to$ Increases

Q. A liquid having mass $m=250\text{g}$ is kept warm in a vessel by using an electric heater. The liquid is maintained at ${50}^{\circ }\text{C}$ when the power supplied by the heater is $30\text{W}$ and the surrounding temperature is ${20}^{\circ }\text{C}$. As the heater is switched off, the liquid starts cooling and it was observed that it takes $10\text{sec}$ for temperature to fall from ${40}^{\circ }\text{C}$ to ${39.9}^{\circ }\text{C}$. Calculate the specific heat capacity of the liquid. Assume Newton's law of cooling to be applicable.

1. $6500{\text{J/kg}}^{\circ }\text{C}$
2. $7473{\text{J/kg}}^{\circ }\text{C}$
3. $7980{\text{J/kg}}^{\circ }\text{C}$
4. $8493{\text{J/kg}}^{\circ }\text{C}$

Q.

Fill in the blanks.

The inspiratory and expiratory centres are present in the___(i)____. The Pneumotaxic and the Apneusticcentres are present in the___(ii)___. The inspiratory system is basically responsible for___(iii).___ The expiratory system become activated during forced ___(iv)___.

1. i).➡Medulla ii).➡Pons iii).➡Inspiration) iv). ➡Expiration.

2. i).➡Pons ii).➡Medulla iii).➡Expiration iv).➡ Inspiration.

3. i).➡Medulla ii).➡ Pons iii).➡Expiration iv).➡ Expiration

4. i).➡Medulla ii).➡ Pons iii).➡Inspiration iv). ➡Inspiration.

Q. A copper sphere is suspended in an evacuated chamber maintained at $300\text{K}$. The sphere is maintained at a constant temperature of $500\text{K}$ by heating it electrically. A total of $300\text{W}$ of electric power is needed to do it. When half of the surface of the copper sphere is completely blackened, $600\text{W}$ is needed to maintain the same temperature of the sphere. Calculate the emissivity of copper.

1. $e=\frac{1}{2}$
2. $e=\frac{1}{3}$
3. $e=\frac{1}{4}$
4. $e=\frac{1}{5}$

Q.

Which of the following is not possible when the pneumotaxic centre is sending a strong signal?

1. Increase in rate of breathing

2. Complete filling of lungs

3. Decreased duration of inspiration

4. Decreased duration of expiration

Q. A planet is at an average distance $d$ from the sun and its average surface temperature is $T$. Assume that the planet receives energy only from the sun, and loses energy only through radiation from its surface. Neglect atmospheric effects. If $T\propto d^{-n}$, the value of $n$

1. $2$
2. $1$
3. $1/2$
4. $1/4$

Q.

A sphere and a cube of same material and same volume are heated upto same temperature and allowed to cool in the same surroundings. The ratio of the amounts of radiations emitted will be

1. 1 : 1

2. $\frac{4\pi }{3}:1$

3. ${\left(\frac{\pi }{6}\right)}^{\frac{1}{3}}:1$

4. $\frac{1}{2}{\left(\frac{4\pi }{3}\right)}^{\frac{2}{3}}:1$

Q. Two metallic spheres $S_1$ and $S_2$ are made of the same material and have got identical surface finish. The mass of $S_1$ is thrice that of $S_2$. Both the spheres are heated to same high temperature and placed in the same room having lower temperature but are thermally insulated from each other. The ratio of the initial rate of cooling of $S_1$ to that $S_2$ is

1. $\frac{1}{3}$
2. $\frac{1}{\sqrt{3}}$
3. $\frac{\sqrt{3}}{1}$
4. ${\left(\frac{1}{3}\right)}^{1/3}$

Q.

what happen to the respiratory process in a man going up a hill?

Q.

Assume that the total surface area of a human body is 1.6 $m^2$ and that it radiates like an ideal radiator. Calculate the amount of energy radiated per second by the body if the body temperature is 37${}^{\circ }$ C.Stefan constant $\sigma$ is $6.0\times {10}^{-8}W/m^2-K^4$.

1. 608 J

2. 887 J

3. 1026 J

4. 902 J

Q.

How is respiration regulated?

Q.

Each square metre of sun’s surface radiates energy at the rate of $6.27\times {10}^{7}W{m}^{-2}$. Assuming that Stefan’s law applies to the radiation, the temperature of sun’s surface is (Stefan’s constant $\sigma =5.7\times {10}^{7}W{m}^{-2}{K}^{-4}$)

1. $(1.1\times {10}^{15})K$

2. $(1.1\times {10}^{15}{)}^{\frac{1}{2}}K$

3. $(1.1\times {10}^{15}{)}^{\frac{1}{3}}K$

4. $(1.1\times {10}^{15}{)}^{\frac{1}{4}}K$

Q.

A spherical black body of radius 12 cm radiates 450 W power at 500 K. If the radius were halved and the temperature doubled, the power radiated would be

1. 225 W

2. 450 W

3. 900 W

4. 1800 W