CBSE Class 11 Biology Breathing and Exchange of Gases MCQs Set D

Question: Which of the following statements is incorrect for ECG of the human heart?
a) It is graphical representation of the electrical activity of the heart during a cardiac cycle.
b) The ECG of a person is obtained by using a machine called electrocardiogram.
c) To obtain a standard ECG, a patient is connected to the machine with three electrical leads.
d) Each peak in the ECG is identified with a letter from P to T that corresponds to a specific electrical activity of the heart.
Answer: b

Question: The nephridia of earthworm are related with —
a) Locomotion
b) Excretion of nitrogenous wastes
c) Digestion
d) Respiration
Answer: b

Question: The path that leads from the throat to the lungs is known as —
a) trachea
b) oesophagus
c) epiglottis
d) larynx
Answer: a

Question: Which of these statements about sphincters of urethra is correct?
a) Internal urethral sphincter is made up of smooth muscles while external urethral sphincter is made up of striated muscles.
b) Internal urethral sphincter is made up of striated muscles while external urethral sphincter is made up of smooth muscles.
c) Both internal and external urethral sphincters are made up of smooth muscles.
d) Both internal and external urethral sphincters are made up of striated muscles.
Answer: a

Question: Which of the following substances are secreted by tubular cells into the filtrate during urine formation?
a) Glucose, amino acid, Na+
b) H+, K+, amino acid
c) Na+, K+, amino acids
d) K+, H+, ammonia
Answer: d

Question: The total lung capacity is represented by —
a) Tidal volume + Vital capacity
b) Tidal volume + Residual volume
c) Vital capacity + Residual volume
d) Inspiratory + Expiratory reserve volumes
Answer: c

Question: Asthma is caused due to —
a) infection of lungs
b) spasm in bronchial muscles
c) bleeding into pleural cavity
d) infection of trachea
Answer: b

Question: Angiotensin–II will lead to all of the following except —
a) Vasoconstriction
b) Hypernatremia
c) Increasing GFR
d) Excretion of Na+ in urine
Answer: d

Question: The structure which prevents the entry of food into the windpipe is —
a) gullet
b) glottis
c) tonsil
d) epiglottis
Answer: d

Question: The net pressure gradient that causes the fluid to filter out from the glomeruli into the capsule is —
a) 50 mm Hg
b) 75 mm Hg
c) 10 mm Hg
d) 30 mm Hg
Answer: c

Question: The blood stem cells are related to which among the following options?
a) Liver
b) Spleen
c) Kidney
d) Bone marrow
Answer: d

Question: Which of the following is incorrect match about the human excretory system?
a) Columns of Bertini: extension of cortex in between the renal pyramids
b) Renal corpuscle: Bowman’s capsule plus glomerulus
c) Cortical nephrons: Vasa recta is absent or highly reduced
d) Podocytes: Cuboidal epithelium of Bowman’s capsule
Answer: d

Question: Membrane separating air in pulmonary alveoli from blood capillaries is —
a) alveolar epithelium
b) cardiac epithelium
c) endothelium of blood capillaries
d) both (a) and (c)
Answer: d

Question: Identify the correct statements regarding urine formation.
a) Countercurrent mechanism works around the PCT and glomerulus.
b) To prevent diuresis, ADH facilitates water reabsorption from the latter parts of the tubule.
c) Maximum reabsorption of electrolytes occurs in the Henle’s loop.
d) A decrease in blood pressure can increase the GFR.
Answer: b

Question: Intercostal muscles are found attached with —
a) diaphragm
b) ribs
c) pleura
d) lungs
Answer: b

Question: Identify the correct statement with reference to transport of respiratory gases by blood.
a) Haemoglobin is necessary for transport of carbon dioxide and carbonic anhydrase for transport of oxygen.
b) Haemoglobin is necessary for transport of oxygen and carbonic anhydrase for transport of carbon dioxide.
c) Only oxygen is transported by blood.
d) Only carbon dioxide is transported by blood.
Answer: b

Question: The correct order of duration of various phases of the cardiac cycle is —
a) Atrial systole < Ventricular systole < Joint diastole < Ventricular diastole < Atrial diastole
b) Atrial systole < Ventricular diastole < Joint diastole < Ventricular systole < Atrial diastole
c) Atrial diastole < Ventricular diastole < Joint diastole < Ventricular systole < Atrial systole
d) All of the above
Answer: a

Question: Select the correct statement.
a) Inter-atrial septum is a thick partition while atrio-ventricular partitions are thin.
b) Mitral valve is having 2 fibrous nonmuscular cusps.
c) Size of heart is equivalent to the size of clenched fist.
d) All of the above.
Answer: c

Question: Which one of the following is the correct statement for respiration in humans?
a) Workers in grinding and stone-breaking industries may suffer from lung fibrosis.
b) About 90% of carbon dioxide (CO2) is carried by haemoglobin as carbaminohaemoglobin.
c) Cigarette smoking may lead to inflammation of bronchi.
d) Neural signals from pneumotaxic centre in pons region of brain can increase the duration of inspiration.
Answer: a

Question: Which of the following has no specialized respiratory structures?
a) Crab
b) Earthworm
c) Salmon
d) Ant
Answer: b

Question: Functional residual capacity can be represented as
a) TV + ERV
b) ERV + RV
c) RV + IRV
d) ERV + TV + IRV
Answer: b

Question: The respiratory mechanism is controlled by
a) Central nervous system
b) Sympathetic nervous system
c) Parasympathetic nervous system
d) Autonomic nervous system
Answer: a

Question: The total volume of air a person can expire after normal inspiration is called
a) Residual volume
b) Vital capacity
c) Expiratory capacity
d) Functional residual capacity
Answer: c

Question: When 1200 mL air is left in the lungs, it is called
a) Vital capacity
b) Tidal volume
c) Residual volume
d) Inspiratory reserve volume
Answer: c

Question: The respiratory centre which regulates respiration is located in
a) Cerebral peduncle
b) Vagus nerve
c) Pons varolii
d) Medulla oblongata
Answer: d

Question: The nose produces ____________ to put moisture in the air and catch dust and bacteria.
a) Mucus
b) Bronchi
c) Cilia
d) Oxygen
Answer: a

Question: What percentage of oxygen is carried by haemoglobin?
a) 90
b) 98
c) 23
d) 73
Answer: b

Question: Which of the following statement is correct?
a) Tracheal rings are of hyaline cartilage.
b) Dorsal side of thoracic chamber is formed by sternum.
c) Expiration occurs when there is negative pressure in lungs.
d) All of the above
Answer: a

Question: The structure which does not contribute to the breathing movements in mammals is
a) Larynx
b) Ribs
c) Diaphragm
d) Intercostal muscles
Answer: a

Question: In mammals, carbon dioxide is transported from tissues to respiratory surface by
a) Plasma
b) R.B.C.
c) W.B.C.
d) Both (a) and (b)
Answer: d

Question: Most oxygen is carried by the blood (i). Most carbon dioxide is carried by the blood (ii).
a) (i) Attached to haemoglobin, (ii) in the form of bicarbonate ions
b) (i) Dissolved in plasma, (ii) dissolved in plasma
c) (i) In the form of H+ ions, (ii) in the form of bicarbonate ions
d) (i) Attached to haemoglobin, (ii) attached to haemoglobin
Answer: a

Question: Mark the correct statement.
a) Volume of residual air is higher than tidal volume
b) Volume of complementary air is higher than tidal volume
c) Volume of supplementary air is lower than residual capacity
d) All of the above
Answer: d

Question: Which of the following gases makes the most stable combination with the haemoglobin of RBCs?
a) CO₂
b) CO
c) O₂
d) N
Answer: b

Question: The volume of air breathed in and out during normal breathing is called
a) Vital capacity
b) Inspiratory reserve volume
c) Expiratory reserve volume
d) Tidal volume
Answer: d

Question: Partial pressure of oxygen in inspired and expired air is ……. and ……. mm of Hg.
a) 100, 46
b) 158, 40
c) 158, 90
d) 100, 95
Answer: b

Question: Which of the following group are supported by incomplete cartilaginous rings?
a) Pharynx, primary & tertiary bronchi and initial bronchioles
b) Trachea, primary & secondary bronchi, and initial bronchioles
c) Larynx, primary, secondary and tertiary bronchi, and initial bronchioles
d) Trachea, primary, secondary and tertiary bronchi, and initial bronchioles
Answer: d

Question: Every 100 ml of oxygenated blood delivers following amount of O₂ to the tissues under normal physiological condition.
a) 5 ml
b) 25 ml
c) 50 ml
d) More than 50 ml
Answer: a

Question: In anaerobic respiration
a) O₂ is taken in
b) CO₂ is taken in
c) O₂ is given out
d) CO₂ is given out
Answer: d

Question: Which one of the following statement is correct?
a) All animals require a medium for cellular respiration
b) In all animals oxygen is transported by blood
c) All animals need oxygen for respiration
d) All of the above
Answer: a

Question: Which of the following statement correctly defines Bohr effect?
a) Rise in p50 with a decrease in CO2 conc.
b) Rise in p50 with decrease in pH.
c) Rise in p50 with increase in O2.
d) Fall in p50 with decrease in pH.
Answer: b

Question: The volume of the air that leaves the lungs in humans is measured by
a) Respirometer
b) Spirometer
c) Sphygmomanometer
d) Monometer
Answer: b

Question: Dissociation of oxyhaemoglobin can be promoted by
a) Low pCO2
b) High pCO2
c) Low body temperature
d) High blood pH
Answer: b

Question: The pneumotaxic centre that can moderate the function of respiratory rhythm centre is located in
a) Dorsal side of medulla
b) Ventral side of medulla
c) Aortic arch and carotid artery
d) Pons varolii
Answer: d

Question: The amount of air remaining in the air passages and alveoli at the end of quiet respiration is called
a) Tidal volume
b) Inspiratory reserve volume
c) Inspiratory capacity
d) Functional residual capacity
Answer: d

Question: Which of the following structure is the actual gas exchange surface in the mammalian respiratory system?
a) Bronchus
b) Alveolus
c) Bronchiole
d) Trachea
Answer: b

Question: With reference to human respiration, which is correct?
a) Pulmonary ventilation is equal to alveolar ventilation
b) Alveolar ventilation is more than pulmonary ventilation
c) Alveolar ventilation is less than pulmonary ventilation
d) Pulmonary ventilation is less than alveolar ventilation
Answer: b

Question: Lungs are present in
a) Mediastinum
b) Pleural cavity
c) Pericardial cavity
d) Thoracic cavity
Answer: d

Question: The smallest and thinnest tube in the lung is
a) Trachea
b) Larynx
c) Bronchi
d) Bronchiole
Answer: d

Question: As blood becomes fully O₂ saturated, haemoglobin combines with ____ molecule(s) of oxygen.
a) 1
b) 2
c) 4
d) 8
Answer: c

Question: Carbonic anhydrase is found in high concentration in
a) Leucocytes
b) Blood plasma
c) Erythrocytes
d) Lymphocytes
Answer: c

Question: p50 value denotes
a) Percentage of oxygen
b) Partial pressure of O₂
c) Percentage of haemoglobin
d) Percentage of oxyhaemoglobin
Answer: b

Question: Residual air mostly occurs in
a) Alveoli
b) Bronchus
c) Nostrils
d) Trachea
Answer: a

Question: Which of the following organ receives electrical messages from the brain for breathing in and out?
a) Diaphragm
b) Bronchi
c) Bronchioles
d) Alveoli
Answer: a

Question: Every 100 ml of deoxygenated blood delivers approximately ________________.
a) 5 ml of CO to the alveoli
b) 6 ml of CO₂ to the plasma
c) 4 ml of CO₂ to the alveoli
d) 7 ml of CO to the plasma
Answer: c

Question: What will be the pO₂ and pCO₂ in the atmospheric air as compared to that of alveolar air?
a) pO₂ lesser and pCO₂ higher
b) pO₂ higher and pCO₂ lesser
c) Both pO₂ and pCO₂ lesser
d) Both pO₂ and pCO₂ higher
Answer: b

Question: Emphysema develops mainly because of
a) Allergy or hypersensitization
b) Spasm of the smooth muscles of bronchioles
c) Cigarette smoking
d) Inflammation of the alveoli
Answer: c

Question: Thoracic chamber is formed (A) by the vertebral column, (B) by the sternum, (C) by the ribs and on the (D) side by the dome-shaped diaphragm. Identify A, B, C and D.
a) A – dorsally, B – ventrally, C – laterally, D – lower
b) A – ventrally, B – laterally, C – dorsally, D – upper
c) A – laterally, B – ventrally, C – dorsally, D – lower
d) A – dorsally, B – laterally, C – ventrally, D – upper
Answer: a

Question: (i) in CO₂ in your blood, which causes (ii) in pH, would cause your breathing to speed up.
a) (i) An increase, (ii) a rise
b) (i) An increase, (ii) a drop
c) (i) A decrease, (ii) a rise
d) (i) A decrease, (ii) a drop
Answer: b

Question: Which of the following statement is incorrect?
a) Diffusion membrane is made up of 3-major layers
b) Solubility of CO₂ is higher than O₂ by 25 times
c) Breathing volumes are estimated by spirometer
d) High conc. of hydrogen ions favours oxyhaemoglobin formation
Answer: d

Question: Which of the following normally contains the highest concentration of oxygen?
a) Body cells
b) Inhaled air
c) Air in the pulmonary trunk
d) Blood entering the lungs
Answer: b

Question: Which of the following statements is correct?
a) Inspiration is a passive process whereas expiration is active.
b) Inspiration is an active process whereas expiration is passive.
c) Inspiration and expiration are active processes.
d) Inspiration and expiration are passive processes.
Answer: b

Question: The correct statement in respect of protein haemoglobin is that it
a) Maintains blood sugar level.
b) Acts as an oxygen carrier in the blood.
c) Functions as a catalyst for biological reactions.
d) Forms antibodies and offers resistance to diseases.
Answer: b

Question: Which of the following statements about the functioning of the kidney is correct?
I. On an average 1100-1200ml of blood is filtered by the kidneys per minute which constitute roughly 1/5th of the blood pumped out by each ventricle of the heart in a minute.
II. JGA is a special sensitive region formed by cellular modification in the distal convoluted tubule and the glomerulus at the location of their contact.
III. The ascending limb of Henle’s loop is impermeable to water but allows transport of electrolytes.
IV. The collecting duct allows passage of small amounts of urea into the medullary interstitium to keep up the osmolarity.
(a) I and II
(b) I, III and IV
(c) I, II, and III
(d) II, III, and IV
Answer: b