Q.41. Which is the correct sequence of air passage during inhalation?
(a) Nostrils →larynx →pharynx →trachea →lungs
(b) Nasal passage →trachea →pharynx →larynx →alveoli
(c) larynx →nostrils →pharynx →lungs
(d) Nostrils →pharynx →larynx →trachea →alveoli
Q.42. During respiration exchange of gases take place in
(a) trachea and larynx (b) alveoli of lungs
(c) alveoli and throat (d) throat and larynx
Q.43. Which of the following statement (s) is (are) true about heart?
(i) Left atrium receives oxygenated blood from different parts of body while right atrium receives deoxygenated blood from lungs
(ii) Left ventricle pumps oxygenated blood to different body parts while right ventricle pumps deoxygenated blood to lungs
(iii) Left atrium transfers oxygenated blood to right ventricle which sends it to different body parts
(iv) Right atrium receives deoxygenated blood from different parts of the body while left ventricle pumps oxygenated blood to different parts of the body
(a) (i) (b) (ii)
(c) (ii) and (iv) (d) (i) and (iii)
Q.44. What prevents backflow of blood inside the heart during contraction?
(a) Valves in heart
(b) Thick muscular walls of ventricles
(c) Thin walls of atria
(d) All of the above
Q.45. Single circulation i.e., blood flows through the heart only once during one cycle of passage
through the body, is exhibited by
(a) Labeo, Chameleon, Salamander
(b) Hippocampus, Exocoetus, Anabas
(c) Hyla, Rana, Draco
(d) Whale, Dolphin, Turtle
Q.46. In which of the following vertebrate group/groups, heart does not pump oxygenated blood to
different parts of the body?
(a) Pisces and amphibians
(b) Amphibians and reptiles
(c) Amphibians only
(d) Pisces only
Q.47. Choose the correct statement that describes arteries.
(a) They have thick elastic walls, blood flows under high pressure; collect blood from different organs and bring it back to the heart
(b) They have thin walls with valves inside, blood flows under low pressure and carry blood away from the heart to various organs of the body
(c) They have thick elastic walls, blood flows under low pressure; carry blood from the heart to various organs of the body
(d) They have thick elastic walls without valves inside, blood flows under high pressure and carry blood away from the heart to different parts of the body.
Q.48. The filtration units of kidneys are called
Q.49. Oxygen liberated during photosynthesis comes from
(c) carbon dioxide
Q.50. The blood leaving the tissues becomes richer in
(a) carbon dioxide (b) water
(c) heamoglobin (d) oxygen