Biology Today — December 2017

1. Which of the following are present in the filiform papillae of
   the tongue?
   (a) Chemoreceptors (b) Thermoreceptors
   (c) Tactile receptors (d) Taste buds


2. Brown colour of faeces is due to
   (a) sodium glycocholate (b) biliverdin
   (c) sodium taurocholate (d) stercobilin.


3. The chemosensitive area of respiratory centre in medulla is
   stimulated by
   (a) excess CO 2 and H+ ions
   (b) less O 2 and H+ ions
   (c) less CO 2 and H+ ions
   (d) excess O 2 and H+ ions.


4. Read the following statements and select the correct option
   stating which ones are true (T) or false (F).
   I. Gluconeogenesis is the formation of glucose from lipid.
   II. Bohr effect has a more enhanced effect on promoting O 2
   transport than Haldane effect has on CO 2 transport.
   III. Pneumotaxic centre’s main function is to control depth of
   expiration.
   IV. Paneth cells present in crypts of Lieberkuhn synthesise
   secretin hormone.
   I II III IV
   (a) T T F F
   (b) T F F F
   (c) T F T T
   (d) F T F T


5. What is the approximate normal composition of alveolar air?
   (a) 14% oxygen, 6% carbon dioxide, 80% nitrogen
   (b) 21% oxygen, 2% carbon dioxide, 77% nitrogen
   (c) 16% oxygen, 3% carbon dioxide, 81% nitrogen
   (d) 10% oxygen, 8% carbon dioxide, 82% nitrogen


6. Observe a section of small intestinal mucosa showing villi.
   Select the option that correctly identifies A, B, C and D.

A

B

D

C

(a) A-Lacteal, B-Villus, C-Capillary, D-Crypts of Lieberkuhn

(b) A-Villus, B-Lacteal, C-Blood vessel, D-Crypts of Lieberkuhn

(c) A-Artery, B-Lacteal, C-Crypts of Lieberkuhn, D-Villus

(d) A-Crypts of Lieberkuhn, B-Lacteal, C-Vein, D-Villus

7. Accessory pancreatic duct is called
   (a) ampulla of Vater (b) duct of Santorini
   (c) duct of Wirsung (d) duct of Rivinus.


8. The partial pressure of O 2 when blood enters and leaves the
   alveolar capillaries are respectively
   (a) 86 mmHg, 35 mmHg (b) 45 mmHg, 80 mmHg
   (c) 75 mmHg, 40 mmHg (d) 40 mmHg, 95 mmHg.


9. The volume of air that always remains inside the human lungs
   is described as
   (a) residual volume
   (b) expiratory reserve volume
   (c) inspiratory reserve volume
   (d) tidal volume.


10. Select the mismatched pair from the following options.
    (a) Peyer’s patches – Produce lymphocytes
    (b) Pleural fluid – Lubricate pleurae to reduce friction
    (c) Lecithin – Lines trachea to prevent collapsing
    (d) Castle’s intrinsic factor – Vitamin B 12 absorption


11. To maintain the ionic balance during the transportation of
    gases, chloride ions shift from
    (a) lungs to blood (b) plasma to RBCs
    (c) RBCs to plasma (d) blood to lungs.

Total Marks : 160 Time Taken : 40 Min.

T

his specially designed column enables students to self analyse their

extent of understanding of specified chapters. Give yourself four

marks for correct answer and deduct one mark for wrong answer.

Self check table given at the end will help you to check your

readiness.

-8 Practice Problems

Class XI

• Digestion and Absorption


• Breathing and Exchange of Gases