Breathing and Exchange of Gases · Biology · MHT CET (Biology)
MCQ (Single Correct Answer)
Select INCORRECT statement about the Hering-Breuer reflex.
Given below are two statements.
Statement I -The right lung is larger and divided into two lobes.
Statement II -The left lung is smaller and divided into three lobes.
In the light of above statements, select the correct option given below:
Select the INCORRECT statements.
i. The rate of formation of $\mathrm{H}_2 \mathrm{CO}_3$ is slower in RBCs and faster in plasma.
ii. Dissociation of $\mathrm{H}_2 \mathrm{CO}_3$ into $\mathrm{H}^{+}$and $\mathrm{HCO}_3^{-}$ takes place due to carbonic anhydrase.
iii. The carbonic anhydrase is present in leucocytes,
iv. The prosthetic group of carbonic anhydrase is Mn .
Select the correct option.
Match the Column I and II
| Column (I) | Column (II) | ||
|---|---|---|---|
| i. | $\mathrm{CO}_2$ dissolved in plasma | a. | 23 % |
| ii. | $\mathrm{CO}_2$ transported as bicarbonate ions | b. | 7 % |
| iii. | $\mathrm{CO}_2$ transported by RBC as carbaminohaemoglobin | c. | 70 % |
| iv. | $\mathrm{O}_2$ transportation by RBCs as oxyhaemoglobin | d. | 97 % |
Choose the correct option:
Due to formation of oxyhaemoglobin, the pH of blood decreases due to release of $\mathrm{H}^{+}$ion and the $\mathrm{H}_2 \mathrm{CO}_3$ dissociates into $\mathrm{H}_2 \mathrm{O}$ and $\mathrm{CO}_2$. This is called __________ .
How does the Hb act as buffer?
The partial pressure of carbon dioxide $\left(\mathrm{ppCO}_2\right)$ of blood entering the pulmonary capillaries is_______.
Haemoglobin has maximum affinity for
Select INCORRECT statements with respects transport of $\mathrm{CO}_2$ by RBCs and plasma.
i. $23 \%$ of $\mathrm{CO}_2$ released from tissue cells diffuse into plasma first and then into RBCs.
ii. Within RBCs carbonic acid immediately dissociates into $\mathrm{H}^{+}$and $\mathrm{HCO}_3^{-}$.
iii. In RBCs $\mathrm{CO}_2$ combines with $\mathrm{H}_2 \mathrm{O}$ to form carbonic acid.
iv. $\mathrm{H}^{+}$ions move out of RBCs and combine with $\mathrm{Na}^{+}$to form $\mathrm{NaHCO}_3$.
v. $7 \%$ of $\mathrm{CO}_2$ is transported in dissolved form as carbonic acid in plasma.
In the light of above statements choose the correct answer from option given below.
Respiratory centres that control the rate and depth of breathing are located in __________