Biology Today — January 2018

1. Which of the following is responsible for initiating the
   rhythmic activity of heart?
   (a) Atrio-ventricular node (b) Sinoatrial node
   (c) Bundle of His
   (d) Pulmonary semilunar valves


2. Select the correct statements for atherosclerosis.
   I. High blood plasma concentration of cholesterol in the
   form of low density lipoprotein (LDL) is responsible
   for atherosclerosis.
   II. Calcification of the plaques makes the walls of the
   arteries stiff and rigid.
   III. Blood leaks from the ruptured wall of arteries may
   clot and block the pathway of blood flow.
   I V. Lumen of the artery decreases and the flow of blood
   is reduced.
   (a) I only (b) II and III
   (c) III and IV (d) I and IV


3. Pick the odd ones in each of the following groups and select
   the correct option.
   (i) Renal pelvis, Medullary pyramid, Renal cortex, Renal
   papilla
   (ii) Afferent arteriole, Glomerulus, Vasa recta, Efferent
   arteriole
   (iii) Glomerular filtration, Antidiuretic hormone,
   Hypertonic urine, Collecting duct
   (iv) Trigone, Urinary bladder, Detrusor muscle, Urethral orifice
   (i) (ii) (iii) (iv)
   (a) Renal Henle’s Collecting Urinary
   pelvis loop duct tubule bladder
   (b) Renal Afferent Antidiuretic Urinary
   papilla arteriole hormone bladder
   (c) Medullary Efferent Hypertonic Detrusor
   pyramid arteriole urine muscle
   (d) Renal Vasa recta Glomerular Urethral
   cortex filtration orifice

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.

Class XI

• Body Fluids and Circulation


• Excretory Products and Their Elimination
  4. Select the incorrect statement.
  (a) Tubular reabsorption takes place by passive and
  active transport.
  (b) ADH decreases the reabsorption of water in the DCT
  and collecting duct.
  (c) Cortical nephrons control plasma volume under
  normal water supply.
  (d) A normal adult person secretes about 1.5 litres of
  urine in 24 hours.
  5. Clotting factors III, VIII, IX and XII respectively are
  (a) Thromboplastin, antihaemophilic factor A, Stuart
  Prower factor and antihaemophilic factor C
  (b) Prothrombin, Calcium, Christmas factor, Glass factor
  (c) Fibrinogen, antihaemophilic factor B, Hageman factor,
  Fibrin-stabilising factor
  (d) Thromboplastin, Antihaemophilic factor A, Christmas
  factor, Glass factor.
  6. Atrial Natriuretic Factor hinders the regulation of kidney by
  (a) renin-angiotensin aldosterone system
  (b) stimulating release of antidiuretic hormone
  (c) inhibiting aldosterone synthesis
  (d) increasing H+ reabsorption in PCT.
  7. Identify A, B, C and D in the given table.
  Leucocytes Percentage of
  leucocyte

Shape of

nucleus

Monocytes 2-10 A

B 0-1 3 lobed

Neutrophils C Many lobed

D 1-6 Bilobed

A B C D

(a) Large rounded Eosinophils 20-45 Lymphocytes

(b) Bean shaped Basophils 40-70 Eosinophils

(c) 5-7 lobed Basophils 40-70 Lymphocytes

(d) S-shaped Lymphocytes 20-45 Basophils