CTET July 2013 Question Paper2 with Answer  
Child Development  Math and Science  Social Science  LanguageI (Eng)  LanguageII (Hindi) 
Candidate have to do questions number 31 to 90 either from PartII ( Mathematics and Science ) or from PartIII ( Social Studies/ Social Science):
PartII: Math and Science
Directions: (Q. 3190) Answer the following questions by selecting the most appropriate option.
Q31. The number of integers less than –3 but greater than –8 is
(a) 2
(b) 3
(c) 4
(d) 6
Answer: (c) 4 Explain: Integers that are less than –3 but greater than –8 are –7, –6, –5, –4 which are total 4 in number. 
Q32. The distance between two places is 12 km. A map scale is 1:25000. The distance between the two places on the map, in cm, is
(a) 24
(b) 48
(c) 36
(d) 60
Answer: (b) 48 Explain: Distance between the two places on the map = $\frac{12}{25000}$km = $\frac{12\times 1000\times 100}{25000}=48cm$ 
Q33. The reciprocal of $\frac{3}{7}\times \left( \frac{7}{13} \right)$ is
(a) 104/21
(c) 21/104
(b) –104/21
(d) –21/104
Answer: (a) 104/21 Explain: $\frac{3}{8}\times \frac{7}{13}\,\,=\frac{21}{104}$ ∴ Reciprocal of given expression = $\frac{104}{21}$ 
Q34. The number of vertices in a polyhedron that has 30 edges and 12 faces is
(a) 12
(b) 20
(c) 15
(d) 24
Answer: (b) 20 Explain: We know that F + V = E + 2 ( where F = faces, V = Vertices, E = Edge ) ⇒ V = 30 + 2 – 12 = 20 
Q35. When half of a number is increased by 15, the result is 39. The sum of digits of the original number is
(a) 6
(c) 9
(b) 7
(d) 12
Answer: (d) 12 Explain: Let the number = x Then x/2 + 15 = 39 ⇒ x/2 = 24 ⇒ x = 48 
Q36. In ΔPQT, PQ = PT. The points R and S are on QT such that PR PS. If ∠PTS = 62° and ∠RPS = 34°, then find the measure of ∠QPR.
(a) 11°
(c) 15°
(b) 13°
(d) 17°
Answer: (a) 11° Explain: In ΔPQT, PQ = PT ∴ ∠PQT = ∠PTQ = 62° Now, ∠PQT + ∠PTQ + ∠QPT = 180 ⇒ 62° + 62° + ∠QPR + ∠RPS + ∠SPT = 180° ⇒ ∠QPR + ∠SPT = 180° – 124° – 34° = 22° ……….(i) And ∠PRQ + ∠PRS = ∠PSR + ∠PST = 180° ∴ ∠PRQ = ∠PST In ΔPQR and ΔPST, PQ = PT, ∠PRQ = ∠PST and PR = PS ∴ ΔPQR ≅ ΔPST ∠QPR = ∠SPT ……. (ii) From (i) and (ii) ∠QPR = ∠SPT = 11° 
Q37. If for ΔABC and ΔDEF, the correspondence CAB ↔ EDF gives a congruence, then which of the following is not true?
(a) AC = DE
(b) ∠A = ∠D
(c) AB = EF
(d) ∠B = ∠F
Q38. 40% of (100 20% of 300) is equal to
(a) 16
(c) 64
(b) 20
(d) 140
Answer: (a) 16 Explain: 40% of (100 20% of 300) $ 
Q39. HCF of two numbers is 28 and their LCM is 336. If one number is 112, then the other number is
(a) 56
(b) 84
(c) 70
(d) 98
Answer: (b) 84 Explain: Product of two number = Product of LCM and HCF ∴ Required number = $\frac{28\times 336}{112}=84$ 
Q40. If $\frac{2}{3}$x=0.6 and 0.02y =1, then the value of x +y^{–1} is
(a) 0.92
(b) 49.1
(c) 1.1
(d) 50.9
Answer: (a) 0.92 Explain: $\frac{2}{3}$x=0.6 ⇒ x = 0.9 and 0.02y =1 ⇒ $\frac{1}{y}$ = 0.02 x +y^{–1} = $x+\frac{1}{y}$ = 0.9 + 0.02 = 0.92 
Q41. If $y=\frac{x2}{x+1}$where y ≠ , then x equals
(a) $\,\,\frac{y+2}{1y}$
(b) $\frac{y+2}{y1}$
(c) $\frac{y2}{y+1}$
(d) $\frac{2y}{1y}$
Answer: (a) $\,\,\frac{y+2}{1y}$ Explain: We have $ 
Q42. A square and a circle have equal perimeters. The ratio of the area of the square to the area of the circle is
(a) 1 : 1
(c) π : 2
(b) 1 : 4
(d) π : 4
Answer: (d) π : 4 Explain: side of the square = b and radius of the area = r Now 4b = 2πr ⇒ $\frac{b}{r}=\frac{2\pi}{4}=\frac{\pi}{2}$ ratio of the area of the square to the area of the circle $=\,\,\frac{b^2}{\pi r^2}\,\,=\,\,\frac{1}{\pi}\times \left( \frac{\pi}{2} \right) ^2=\frac{\pi}{4}$ 
Q43. ABCD is a square with AB = (x +16) cm and BC = (3x). The perimeter (in cm) of the square is
(a) 16
(b) 24
(c) 32
(d) 96
Answer: (c) 32 Explain: 3x = x + 16 ⇒ x = 8 ( all side of square are equal) ∴ perimeter of the square = 4 × 8 = 32 
Q44. The mean of 10 numbers is 0. If 72 and –12 are included in these numbers, the new mean will be
(a) 0
(b) 6
(c) 5
(d) 60
Answer: (c) 5 Explain: mean of 10 numbers is 0 Then sum of 10 numbers is also 0 If two number included then total number = 12 Sum of 12 number = 0 + 72 – 12 = 60 New mean = 60/12 = 5 
Q45. The circumference of the base of a right circular cylinder is 44 cm and its height is 15 cm. Find the volume (in cm^{3}) of the cylinder. (Use π = 22/7)
(a) 770
(c) 1540
(b) 1155
(d) 2310
Answer: (d) 2310 Explain: Let radius = r ∴circumference = 2πr = 44 r = $\frac{44}{2\pi}=7$ volume = πr^{2}h = $\frac{22}{7}\times 7^2\times 15=2310$ 
Q46. A Class VII teacher wants to discuss the following problem in the class:
“A square is divided into four congruent rectangles. The perimeter of each rectangle is 40 units. What is the perimeter of the given square?
Key mathematical concepts required to solve this problem are
(a) area of square and rectangle and perimeter, and definition of square and rectangle
(b) meaning of the terms square, rectangle, congruent, perimeter, etc.
(c) area of a rectangle, the perimeter of a square
(d) formation of the algebraic equation to solve the problem
Answer: (b) meaning of the terms square, rectangle, congruent, perimeter, etc. Explain: The students should be clear about the termssquare, rectangle,. congruent, perimeter, etcthen only can they efficiently take part in the related discussions. 
Q47. Algebra is introduced in the middle classes. According to Piaget’s theory of cognitive development, it is appropriate to introduce algebra at this stage a
(a) the child is at sensorymotor stage and can understand with the help of lots of manipulative
(b) the child is at preoperational stage and can understand abstract concepts
(c) the child is at the concreteoperational stage and can understand and conceptualize concrete experiences by creating logical structure
(d) the child is at formal operational stage and is fully mature to grasp the abstract concepts.
Answer: (c) the child is at the concreteoperational stage and can understand and conceptualize concrete experiences by creating a logical structure Explain: Children at the concreteoperational stage are aged between 7 and 11 years. This period marks the beginning of logical thinking in them. Therefore, it is the best time to introduce algebra to them, as this field of mathematics is more advanced than arithmetic. Apart from numbers, It also includes variables, which are denoted by letters. 
Q48. Mr. Sharma was assessing the students’ work on exponents. One of the response sheets was as follows:
(I) 23 x 25 = 28
(II) 32 x 42= (12)^{4}
(III) 33 ÷ 35 = 3^{–2}
(IV) 720 ÷ 714 = 7^{6}
(V) 93 ÷ 186 = (1/2)^{3}
On the basis of this response sheet,
Mr. Sharma can make the following observations:
(a) Child has understood the laws of exponents and can apply them well.
(b) Child has understood the laws of exponents but has made clerical errors.
(c) Child has understood the laws of exponents but has not practiced the questions involving division of two numbers.
(d) Child has understood the law of exponents for the cases where the base is same and has missed the concept for the case where the base is different.
Answer: (d) Child has understood the law of exponents for the cases where the base is same and has missed the concept for the case where the base is different. Explain: The child is unclear about the rules of simplifying exponential expressions when the bases are different or both bases and their exponents are different. In the former case, the bases should e multiplied or divided first. In the latter case, each exponent should be resolved apart and their multiplied or divided. 
Q49. According to Van Hiele levels of geometric thought, the five levels of geometric understanding are visualization, analysis, informal deduction, formal deduction and rigor. Students of class VIII are asked to classify the quadrilaterals according to their properties. These students are at …………. level of Van Hiele geometrical thought.
(a) visualization
(b) analysis
(c) informal deduction
(d) formal deduction
Answer: (b) analysis Explain: The students are at analysis level of Van Hiele model of geometric thinking. They classify shapes on the bases of their properties at this stage. 
Q50. A task assigned to a class VIII student is as follows:
An open box is to be made out of a metallic sheet of 50 cm x 65 cm. Length and breadth of the box are 30 cm and 15 cm respectively. What is the possible height of the box? Also find the volume of this box. This task refers to
(a) lower level of cognitive demand as it requires the knowledge of formulae of volume of cuboids
(b) lower level of cognitive demand as there is no connection between concepts involved and procedure required
(c) higher level of cognitive demand as the problem can be solved by making diagrams and connections between many possible situations
(d) higher level of cognitive demand as it requires the use of conceptual understanding that underlines the procedure to complete the task
Answer: (d) higher level of cognitive demand as it requires the use of conceptual understanding that underlines the procedure to complete the task Explain: Such types of mathematical tasks cal for higher level of cognitive demand, in order to analyze, think laterally, initiate, reason logically and persist until he problem is solved. 
Q51. Mr. Nadeem gave the following task to his class, after completing the topic on lines and angles:
Speak for 2 minutes on the following figures using your knowledge about lines and angles:
This task is
(a) reflective in nature, can be used to pass time
(b) exploratory in nature, can be used for summative assessments
(c) reflective as well as can be used for formative assessment
(d) communicative and can encourage mathematical talk in the classroom during tree time
Answer: (c) reflective as well as can be used for formative assessment Explain: It is a reflective task in which the students have been asked to think, analyze and say anything about lines and angles. The responses of the students can be used for formative assessment. 
Q52. A child of class VII defined the rectangle as follows:
“Rectangle is a quadrilateral whose opposite sides are parallel and equal”
The definition reflects that the child
(a) cannot recognize the shape
(b) does not know the correct properties of the shape
(c) knows the properties of the shape, but repeated some properties in definition
(d) knows some properties, but missed some other important properties to complete the definition
Answer: (d) knows some properties but missed some other important properties to complete the definition Explain: The child is not aware of all the important properties of a rectangle, Such as all its angles are right angles. 
Q53. A very common error observed in addition of linear expression is
5y +3 = 8y.
This type of error is termed as
(a) clerical error
(b) procedural error
(c) conceptual error
(d) careless error
Answer: (c) conceptual error Explain: It Is a conceptual error. The student does not know how to solve linear expressions. He/she simply adds a variable to a constant. 
Q54. Read the following question from class VI textbook:
“Prabal deposited Rs 5,000 in a bank at the rate of 5% interest per annum. After 2 years, he withdrew the money to purchase the study table for Rs 3,500. He deposited the money left with him again at the rate of 5% interest per annum for another two years. How much amount will he receive after two years?”
What values can be inculcated in students through this question?
(a) Honesty
(b) Habit of saving money and spending it wisely
(c) Sincerity
(d) Simplicity and helping others
Answer: (b) Habit of saving money and spending it wisely Explain: The question reflects that Prabal is saving money in the bank. So, it helps to inculcate the value of saving money in the students. 
Q55. Following is a problem from textbook of class V:
“Express the following statement through linear expression:
Neha has 7 more toffees than Megha. If Megha has x toffees, how many toffees does Neha have?” which competence of Bloom’s cognitive domain is referred to in the above question?
(a) Comprehension
(b) Synthesis
(c) Knowledge
(d) Analysis
Answer: (a) Comprehension Explain: The question refers to the comprehension competence of Bloom’s cognitive domain. The students need to comprehend the language of the problem and then convert it into a mathematical equation to get answer. All this requires proper comprehensions. 
Q56. If p = 3^{2000} + 3^{–2000} and q = 3^{2000} – 3^{–2000}, then the value of p^{2} – q^{2} is
(a) 1
(c) 3
(b) 2
(d) 4
Answer: (d) 4 Explain: p^{2} – q^{2} = (p +q)(p – q) = (3^{2000} + 3^{–2000} + 3^{2000} – 3^{–2000}) (3^{2000} + 3^{–2000} – 3^{2000} + 3^{–2000}) = 2.3^{2000} ×2.3^{2000} = 4.3^{20002000} = 4 
Q57. The square of 9 is divided by the cube root of 125. The remainder is
(a) 1
(b) 2
(c) 3
(d) 4
Answer: (a) 1 Explain: square of 9 = 81 and cube root of 125 = 5 Remainder if 81 divided by 5 = 1 
Q58. The value of $\sqrt{16\sqrt{8\sqrt{4}}}$ is
(a) 16
(b) 8
(c) $8\sqrt[3]{2}$
(d) $16\sqrt{2}$
Answer: (b) 8 Explain: $\sqrt{16\sqrt{8\sqrt{4}}}$ $=\sqrt{16\sqrt{16}}$ $=\sqrt{64}=8$ 
Q59. Onehalf of 1.2 x 10^{30} is
(a) 6.0 x 10^{30}
(b) 6.0x 10^{29}
(c) 0.6 x 5^{30}
(d) 1.2 x 10^{15}
Answer: (b) 6.0x 10^{29} Explain: Onehalf of 1.2 x 10^{30} = 0.6 x 10^{30} = 6 x 10^{29} 
Q60. 2/3, 23/30, 9/10, 11/15 and 4/5 are written in ascending order, then the fraction in the middle most will be
(a) 23/30
(b) 4/5
(c) 2/3
(d) 11/15
Answer: (a) 23/30 Explain: multiplying with LCM of denominator are
ascending order = 20, 22, 23, 24, 27 the middlemost = 23 = 23/30 
Q61. The steps required for the conversion of kitchen garbage into manure are given below in a jumbled form.
(A) Put the garbage in the pit.
(B) Cover the bottom of the pit with sand.
(C) Cover the pit loosely with grass or a gunny bag.
(D) Add worms.
The correct sequence of these steps is:
(a) (B), (A), (C), (D)
(b) (B), (C), (A), (D)
(c) (B), (A), (D), (C)
(d) (B), (D), (A), (C)
Answer: (c) (B), (A), (D), (C) Explain: Manure is the organic matter, formed by the which decomposition of plants and animal waste. To prepare manure, the first step is to prepare a pit by covering it with sand. The garbage (plant and animal waste) is then put into the pit along with the worms that help in decomposition. Now the pit is covered for some time with gunny bags or grass. The process may take around 30 days or more to complete. 
Q62. Two organisms are best friends and live together. One provides shelter, water and nutrients while the other prepares and provides food. Such an association of organisms is termed as
(a) autotrophy
(b) parasitism
(c) heterotrophy
(d) symbiosis
Answer: (d) symbiosis Explain: In symbiotic association, two organisms live together to obtain benefits from one another. 
Q63. In the alimentary canal, the swallowed food moves downwards because of
(a) the contraction of muscles in the wall of food pipe
(b) the flow of fluid material taken with the food
(c) gravitational pull
(d) the force provided by the muscular tongue
Answer: (a) the contraction of muscles in the wall of food pipe Explain: Peristalsis is the process that occurs in the esophagus (food pipe), pushing the food into the stomach. In this process, the wall of esophagus contracts in order to push the food downward. 
Q64. Frogs and earthworms breathe through their skin because of which the skin of both the organisms is
(a) dry and rough
(b) dry and slimy
(c) moist and rough
(d) moist and slimy
Answer: (d) moist and slimy Explain: Cutaneous respiration is the process in which the exchange of gases occurs through the skin of the animals. Frogs and earthworms are examples of animals that perform this type of respiration. The skin of these animals needs to be moist so that oxygen and carbon dioxide can easily pass through it. 
Q65. While going for a picnic, a student noted the reading on the odometer on the bus every 10 minutes until the end of the journey. Later on, he recorded in a table shown below:
Time (AM)  Odometer Reading (km) 
8.00  78752 
8.10  78758 
8.20  78768 
8.30  78780 
8.40  78791 
8.50  78800 
9.00  78806 
The average speed of the bus in the entire journey in meters per second was
(a) 15
(b) 18
(c) 30
(d) 54
Answer: (a) 15 Explain: The average distance can be calculated by the following formula: Average speed = Total Distance/ Total Time Total distance travelled by the bus = 78,806 km – 78,752 km = 54 km Total time taken by the bus 1 h Average speed = 54/ 1= 54 km/h, In m/s (54 x1000)/3600 = 15 m/s 
Q66. You are provided with a concave mirror, a concave lens, a convex mirror and a convex lens. To obtain an enlarged image of an object, you can use either
(a) concave lens or convex lens
(b) concave mirror or convex mirror
(c) concave mirror or concave lens
(d) concave mirror or convex lens
Answer: (d) concave mirror or convex lens Explain: The images formed by the convex mirror and concave lens are always reduced in size, virtual and erect. The images formed by the concave mirror and convex lens depend upon the distance of the object from the mirror and lens, respectively. So, an enlarged image of the object can be obtained by using the concave mirror or convex lens. 
Q67. Select from the following a set of Kharif Crops:
(a) Cotton, paddy, pea, linseed
(b) Paddy, maize, cotton, soyabean
(c) Gram, mustard, groundnut, wheat
(d) Maize, paddy, linseed, soyabean
Answer: (b) Paddy, maize, cotton, soyabean Explain: Kharif crops are the crops that are planted during June or July and harvested after the monsoon, i.e. September or October. This is because they require a large amount of water. Examples of kharif crops are paddy, maize, soya bean, cotton and millet 
Q68. Study the following statements about the effects of weeds on the crop plants:
(A) They help crop plants to grow healthily.
(B) They interfere in harvesting
(C)They affect plant growth.
(D) They compete with crop plants for water, nutrients, space, and light.
The correct statements are:
(a) (C) and (D) only
(b) (D) only
(c) (B), (C) and (D)
(d) (A), (B) and (D)
Answer: (c) (B), (C) and (D) Explain: Weeds are the unwanted plants that grow with the crop plants and affect their growth by competing with them for food, water, light and space. Weeds are removed from the fields either manually or by applying weedicides. 
Q69. When we add aluminum foil to freshly prepared sodium hydroxide solution gas is produced. Which of the following correctly states three properties of this gas?
(a) Colorless and odorless gas which extinguishes a burning match stick.
(b) Colorless and Odorless gas promotes the burning of a candle.
(c) Brown colored pungentsmelling gas.
(d) Colorless and odorless gas which produces a pop’ sound when a burning match stick Is brought near it
Answer: (d) Colorless and odorless gas which produces a pop’ sound when a burning match stick Is brought near it Explain: Aluminum is a metal; so when it reacts with sodium hydroxide, hydrogen gas is produced. The following reaction takes place. 2 Al +2 NaOH + 6H_{2}O →(Heat) 2NaAl(OH)_{4} + 3H_{2} A pop sound is produced due to the release of odorless and colorless hydrogen gas. 
Q70. An aqueous solution of which of the following oxides will change the color of blue litmus to red?
(a) Copper oxide
(c) Magnesium oxide
(b) Iron oxide
(d) Sulfur dioxide
Answer: (d) Sulfur dioxide Explain: Litmus paper is used for testing the acidic or basic nature of a substance. There are two color litmus papers, i.e. red and blue. If red litmus turns blue on dipping in a solution, it shows the given solution is basic. If blue litmus turns red on dipping in a solution, it shows the given solution is acidic. Sulfur dioxide is produced from sulfuric acid. It Is volatile and acidic in nature. So, it will turn the blue litmus red. Other solutions, copper Oxide, iron oxide, and magnesium oxide are basic in nature. 
Q71. Which of the following is a pair of exhaustible natural resources?
(a) Coal and soil
(b) Petroleum and water
(c) Minerals and wildlife
(d) Natural gas and sunlight
Answer: (c) Minerals and wildlife Explain: Natural resources are either exhaustible or inexhaustible. Exhaustible natural resources are those which cannot be recycled in nature, so they need to be used judiciously to be preserved for future generations. Examples include coal, petroleum, minerals, and wildlife. Inexhaustible natural resources are those which are present in nature in unlimited quantity and can be recycled by nature. Examples include solar energy, water, and wind energy. 
Q72. Which of the following statements is true about endemic species?
(a) They are not affected by the destruction of their habitat.
(b) They are found only in zoos and botanical gardens.
(c) They are found exclusively in a specific habitat.
(d) Endemic species can never become endangered.
Answer: (c) They are found exclusively in a specific habitat. Explain: Endemic species are those species of living organisms that are found in a specific area exclusively. They are not present anywhere else in the world. Example: The Indian rhinoceros found in the Kaziranga National Park is an endemic species of India. 
Q73. Which of the following pairs is related to the inheritance of characters?
(a) Chromosomes and genes
(b) Chromosomes and mitochondria
(c) Cell membrane and cell wall
(d) Cell membrane and chloroplast
Answer: (a) Chromosomes and genes Explain: The hereditary units of organisms are genes. They carry the hereditary information from the parents to their offspring. Genes are condensed in the chromosomes that are located in the nucleus of the cell. Cell wall and cell membranes are the outer coverings of the plant cell and animal cell, respectively. Mitochondria are the cell organelle responsible for energy production in the cell. A chloroplast is a cell organelle found in the plant. It carries out photosynthesis. 
Q74. Out of the different combinations of terms given below, the correct combination of terms with reference to an animal cell is
(a) Nucleus, plastid, cell membrane, cell wall
(b) Nucleus, chromosome, ribosome, cell wall
(c) The cell membrane, chromosome, ribosome, mitochondria
(d) The cell membrane, ribosome, chloroplast, mitochondria
Answer: (c) Cell membrane, chromosome, ribosome, mitochondria Explain: The difference between plant and animal cells is that the animal cells do not possess plastids and cell walls. Also, vacuoles in animal cells are smaller in size. A typical animal cell is composed of the cell membrane, nucleus, ribosome, mitochondria, Golgi apparatus, endoplasmic reticulum, vacuoles and lissome. 
Q75. Consider the following sets of reproductive terms
(A) Sperm, oviduct, egg, uterus
(B) Ovulation, egg, oviduct, uterus
(C) Sperm, testis, sperm duct, penis
(D) Menstruation, egg, oviduct, uterus
The sets of a correct combination are:
(a) (A), (B) and (C)
(b) (B), (C) and (D)
(c) (C), (D) and (A)
(d) (A), (B) and (D)
Answer: (b) (B), (C) and (D) Explain: Sperm, testis, sperm duct and penis are parts of the male reproductive system. Oviduct, ovaries, egg, and uterus are parts of the system. Menstruation is the process in which the unfertilized egg along with the broken lining of the uterus is removed from the body through the female reproductive vagina. 
Q76. Which of the following elements must be available in the water for the metamorphosis of tadpoles?
(a) Chlorine
(b) Bromine
(c) Sulfur
(d) Iodine
Answer: (d) Iodine Explain: Iodine is an important element that plays a vital role in the process of metamorphosis. he process or changes by which the tadpole is converted into an adult frog is known as metamorphosis. 
Q77. Which one of the following is not the objective of teaching of Science at upper primary stage?
(a) Developing questioning and enquiring skills
(b) Acquiring technological sills
(c) Acquiring process skills
(d) Acquiring scientific literacy
Answer: (b) Acquiring technological sills Explain: Acquiring technological skills is not an objective of teaching science at upper primary level. 
Q78. National Curriculum Framework (NCF) strongly recommends that Science education at upper primary stage should
(a) prepare students for competitive examinations
(b) help students to be emotionally balanced
(c) help students to acquire computational skills
(d) follow constructivistic approach for teaching and learning of the subject
Answer: (d) follow constructivistic approach for teaching and learning of the subject Explain: Science education at upper primary level should follow a constructivist approach wherein the students are provided a favorable environment in which they explore and construct their own knowledge. 
Q79. “Cognitive validity of Science curriculum at upper primary stage requires that it should
(a) be age appropriate and within the reach of students understanding level
(b) convey scientifically correct content
(c) nurture the natural curiosity and creativity of the learners
(d) enable the students to appreciate how the concepts of Science evolve with time
Answer: (a) be age appropriate and within the reach of students understanding level Explain: Cognitive validity requires an age appropriate science curriculum, that is within the reach of students understanding level. 
Q80. Which of the following does not reflect the personality attribute of a person having scientific temper?
(a) Seeking evidence
(b) Biased opinion
(c) Rational thinking
(d) Open mindedness
Answer: (b) Biased opinion Explain: A person having scientific temper does not have biased opinion about anything/person. 
Q81. NCERT Science textbooks for upper primary classes include large number of daily life related questions that have been left unanswered. This has been done that
(a) teachers have a good p0ol of questions for assessment purpose
(b) students can send these questions to scientists to get the answer
(c) teachers can use these questions for home assignment
(d) students can seek answer to these questions by exploring different resources
Answer: (d) students can seek answer to these questions by exploring different resources Explain: The daily life related questions have been left unanswered so that the students think, explore their environment, and seek examples from their environment to answer the questions. This will help them realize the utility of science in their everyday life and also sharpen their reasoning and analytical competence. 
Q82. While teaching the correct method of reading a clinical thermometer to class VIII students, Neha mentions the following necessary precautions to be taken:
Which one of the below precautions has been mentioned wrongly by the teacher?
(a) Thermometer should be washed with hot water before and after use.
(b) Do not hold the thermometer by the bulb while taking the reading.
(c) Ensure that before use, the mercury level in the thermometer is below 35 C.
(d) Read the thermometer keeping the level of mercury along the line of sight
Answer: (a) Thermometer should be washed with hot water before and after use. Explain: Washing the thermometer with hot water will make the temperature in the thermometer rise beforehand. And if the temperature of hot water is above 42°C, the thermometer is prone to break. 
Q83. The section on ‘activities and projects’ included in the exercises of NCERT. Science textbooks for class VI primarily aims at
(a) enhancing in depth understanding of the basic concepts
(b) keeping the students engaged during vacations
(c) assessing the students on practical skills
(d) providing opportunity to students for extended learning
Answer: (a) enhancing in depth understanding of the basic concepts Explain: The section on activities and projects included in the exercises of Science textbooks primarily aims at enhancing in depth understanding of the basic concepts. Their understanding of the concepts learnt in the chapter becomes deeper and clearer and they feel a sense of achievement after completion of each activity or project. 
Q84. Major objective of organizing Science Exhibitions is
(a) grade students on practical skills
(b) provide opportunity to students to compete with others
(c) provide opportunity to students to showcase their creative ideas
(d) provide opportunity to students to enhance their academic performance
Answer: (c) provide opportunity to students to showcase their creative ideas Explain: Science exhibitions provide an opportunity to the students to showcase their creative ideas. They try to make something new and useful which in the long run motivates them to innovate new things. Improvement in academic and practical skills Is a byproduct of their involvement in creative activities. 
Q85. Four candidates appearing in an interview for the post of science teacher were asked to give a demonstration lesson to class VIII students on the topic Pressure exerted by liquids and gases. Following different approaches were followed by different candidates
(a) Detailed explanation of related concepts with the help of diagram on the blackboard
(b) Use of charts for explanation of different concepts
(c) Organization of handson student activities followed by discussions
(d) Greater focus on classroom questions during the lecture
Which one of the above approaches will be most effective for teaching of the topic?
Answer: (c) Organization of handson student activities followed by discussions Explain: Organization of handson student activities followed by discussions will keep the class actively involved in the learning process and give students clear and practical understanding of the concept of pressure exerted by liquids and gases. This is the way science should be taught. 
Q86. The technique of ‘classroom questioning’ in teaching of Science can be more effectively used for
(a) ensuring levels of learning
(b) developing problem solving skills
(c) maintaining discipline in the class
(d) promoting creativity and innovativeness
Answer: (b) developing problem solving skills Explain: Classroom questioning can be used for developing problem solving skil in students. Well framed questions make the students think and present their ideas to solve the problem being discussed in the class. Sometimes, instead of explaining or answering a question, teacher asks another question which serves as a hint to the answer of the previous question. 
Q87. Given below are the steps to test the presence of proteins in a food item. These steps are not in correct sequence.
(A) Take a small quantity of food item in a test tube, add 10 drops of water to it and shake it.
(B) Make the paste or powder of the food to be tested.
(C) Add 10 drops of caustic soda solution to the test tube and shake well.
(D) Add 2 drops of copper sulfate to it.
The correct sequence of these steps is
(a) (A), (B), (D), (C)
(b) (8), (A), (D), (C)
(c) (B), (A), (C), (D)
(d) (D), (B), (A), (C)
Answer: (b) (8), (A), (D), (C) Explain: The steps for testing the presence of proteins in the food are as follows:

Q88. Which of the following terms constitute the female part of a flower?
(a) Stigma, ovary and stamen
(b) Stigma, ovary and style
(c) Stamen, ovary and style
(d) Stamen, petals and sepals
Answer: (b) Stigma, ovary and style Explain: Flower is the reproductive organ of the plants. It may contain either male or female reproductive part or both. Stamen and pistil represent male and female reproductive organs of a flower, respectively. Stamen contains a filament and anther (contain pollens). Pistil consists of three parts, i.e. stigma (receives pollens), style (carries the pollen to ovule) and ovary (contains ovule). 
Q89. How many muscles work together to move a bone?
(a) Two
(b) Four
(c) Six
(d) Number is not fixed.
Answer: (a) Two Explain: Bones move by the working of and two muscles, i.e. agonist and antagonist’s muscles. The agonist’s muscles are the acting muscle while the antagonist muscle works opposite the agonist muscle to prevent the injury and control the movement of bones. 
Q90. Choose the set that represents only the biotic component of a habitat.
(a) Sand, turtle, crab, rocks
(b) Insects, frog, fish, aquatic plants
(c) Tiger, deer, grass, soil
(d) Insects, water, aquatic plants, fish
Answer: (b) Insects, frog, fish, aquatic plants Explain: There are two components of habitat, i.e. biotic and abiotic. The abiotic components include all the nonliving things like water, air, rocks, soil, and sand. The biotic components include all the living things like animals, plants, insects, and microorganisms. 