Common Physical Biological Sciences Practice Test 3

Question – 1

1. A vector of magnitude 100 makes

3.3i??? an angle of 60o with the positive x-axis. What is the horizontal component of the vector?

  • A. 50

  • B. 76.6

  • C. 119.2

  • D. 115

  • E. 0

  • Answer:A

  • Answer Explanation:
    Horizontal component of the vector is given as
    x = A cos ??
    A = 100
    ?? = 60 0

    Hence, x = 100 cos600
    Or, x = 50
    Hence, a is the correct answer option.

Question – 2

2. In which part of the human body are Nissl’s granules present?

  • A. Osteoblasts

  • B. Neuron

  • C. Chondroblasts

  • D. Goblet cell

  • E. All of the above

  • Answer:B

  • Answer Explanation:
    Nissl’s granules are present in the cell body of neuron. These are the site of protein synthesis in neurons and are made of rough endoplasmic reticulum and ribosome. It was named after Franz Nissl.

Question – 3

3. Predict whether the following half cell reactions are Oxidation or Reduction.(i) Cu2+(aq) + 2e ????????? Cu(s)(ii) Cu(s) ????????? Cu2+ (aq) + 2e

  • A. I- Oxidation reaction, II- Reduction reaction

  • B. I- Reduction reaction, II- Oxidation reaction

  • C. Both I and II are Oxidation reactions

  • D. Both I and II are Reduction reactions

  • E. None of the above

  • Answer:B

  • Answer Explanation:
    Reduction reaction is one in which, an atom or an ion accepts an electron. Oxidation reaction is one in which, an atom or an ion releases an electron. In the first reaction, Cu2+ion accepts two electrons. Therefore, it undergoes reduction. In the second reaction, Cu atom releases two electrons. Therefore, it undergoes oxidation.

Question – 4

4. Inhibition of lateral buds by the terminal bud is called

  • A. Apical impulse

  • B. Apical hindrance

  • C. Apical resistance

  • D. Apical dominance

  • E. None of these

  • Answer:D

  • Answer Explanation:
    Apical dominance is the phenomenon in which the terminal (apical) buds suppress the growth of lateral or axillary buds. Apical impulse is the pulse over the apex of the heart.

Question – 5

5. What is the angle between the vectors,



  • A. 400

  • B. 350

  • C. 300

  • D. 38.340

  • E. 450

  • Answer:E

  • Answer Explanation:
    To find the angle between the two vectors we need to use dot product. According to dot product
    A – B = |A| |B| cos ??
    A and B are two vectors;
    |A| is the magnitude of vector A;
    |B| is the magnitude of vector B;
    ?? is the angle between the two;
    A =
    i???+k??? and B =

    k???|A| =

    1+0+1 Or, |A| = ???2
    |B| =

    0+0+1 (Since coefficients of x and y are qual to zero
    Or, |B| = 1


    k??? = ???2 x 1 x cos??
    Dot product between two orthogonal vectors is always zero. For example, dot product between the coefficients of x and y axis will result zero. Coefficients along the same axis provide non-zero result for dot product.




    k??? = ???2cos??————-(1)


    k??? = |i| x |k| cos900


    k??? = 0
    Where as


    k??? = |k| |k| cos0(lying on the same axis)
    Unit vector has magnitude of one, |k| = 1. Therefore,


    k??? = 1 cos0??


    k??? = 1 —————–(2)
    Putting the equation 2 in 1 we get,
    1 = ???2cos&theta
    Or, cos ?? =

    12 Or, ?? = 450
    Hence, e is the correct answer option.

Question – 6

6. Choose the octet structure of carbon monoxide

  • A. ??????C

  • B.

  • C.

  • D.

  • E.

  • Answer:A

  • Answer Explanation:
    In carbon monoxide, carbon is connected with oxygen by a triple bond. In that two are sigma bonds and another one is dative bond. Therefore, both carbon and oxygen contain only one lone pair each.

Question – 7

7. What is the unit vector along 3.3




  • A. 0.6i^+0.67j^+0.44k^

  • B. 0.6i^+0.67j^+k^

  • C. i^+0.67j^+k^

  • D. i^+j^+k^

  • E. i^+k^

  • Answer:A

  • Answer Explanation:
    Unit vector has magnitude of one and points in the direction along the vector concerned. Unit vector can be given as
    a??? =


    A??? is any vector;
    |A| is the magnitude of


    a??? is the unit vector a long


    A??? = 3.3



    k???|A| =

    3.32+3.72+2.42|A| =

    30.34|A| = 5.5

    a??? =


    a??? = 0.6



    k???Unit vector along 3.3



    k??? is 0.6



    k???Therefore, a is the correct answer option.

Question – 8

8. The volume of air inspired or expired during one respiratory cycle is known as

  • A. Inspiratory reserve volume

  • B. Expiratory reserve volume

  • C. Tidal volume

  • D. Residual volume

  • E. None of the above

  • Answer:C

  • Answer Explanation:
    Tidal volume represents the lung volume. Tidal volume is the total volume of air inspired or expired during one respiratory cycle. Inspiratory reserve volume is the additional volume of air a person can inspire by a forcible inspiration. Expiratory reserve volume refers to the additional volume of air a person can expire forcibly. Residual volume is the volume of air present in lungs even after forcible exhalation.

Question – 9

9. Consider


B??? two vectors given

A??? =



k??? and

B??? = 3



k??? Whice of the following statement is correct for

A??? and


  • A. |A| = 1

  • B. |B| = 1

  • C. Angle between A and B is cos-1(0.78)

  • D. Vector A and B are perpendicular to each other

  • E. A^B^ = 0

  • Answer:C

  • Answer Explanation:
    Magnitude of A and B is given as
    |A| =
    12+2.22+1.52 Or, |A| = 2.84
    Hence, option A is incorrect.
    |B| =

    32+12+2.62 Or, |B| = 4.1






    k???) = 2.84 ?? 4.1 cos??
    or, (


    i???) + (2.2


    j???) + (1.5


    k??? = 2.84 ?? 4.1 cos??
    Dot product between the coefficients of orthogonal axes vanishes.
    Hence, 3+2.2+3.9 = 2.84 ?? 4.1cos??
    Or, 9.1 = 11.64 ?? cos?? ————(1)
    Options d and e are incorrect since, dot product between a and b is not zero. If two vectors are perpendicular to each other, then the angle between them is 90ohence,
    A-B = |A| |B| cos??
    Here ?? = 900
    Therefore, A-B = |A| |B| cos900
    Or, A – B = 0
    Since, dot product between A and B here is not zero so, they are not perpendicular to each other.
    From equation (1)
    Or, cos?? = 0.78
    Or, ?? = cos-1(0.78)
    Hence, the c is the correct answer option.

Question – 10

10. Glucocorticoid is produced by

  • A. Adrenal medulla

  • B. Adrenal cortex

  • C. Pancreas

  • D. Pineal gland

  • E. Pituitary gland

  • Answer:B

  • Answer Explanation:
    Glucocorticoids are produced by the adrenal cortex. Glucocorticoids are a class of steroid hormones that bind to the glucocorticoid receptor. They stimulate gluconeogenesis andincrease the blood glucose level.

Question – 11

11. Which of following is required to keep a body in static equilibrium?

  • A. Unbalanced force

  • B. Balanced force

  • C. Acceleration

  • D. Non-zero resultant force

  • E. Non-zero tension

  • Answer:B

  • Answer Explanation:
    To keep body in static equilibrium we require either balanced force or body should be moving with uniform velocity (not accelerating). For example, a body kept on horizontal plane is in static equilibrium because weight (acting downwards) being balanced by the normal force acting upwards. Hence, b is correct answer option. If an unbalanced force acts on a body it starts accelerating and hence ais incorrect. For a body to be in equilibrium, it should have zero acceleration hence c is incorrect. For non-zero resultant force, unbalanced force results and hence d is incorrect as well. Tension is nothing but force, hence non-zero tension results in unbalanced force which does not result in equilibrium state of the body therefore, e is incorrect as well.

Question – 12

12. Conjunctivitis also known as

  • A. Black eye

  • B. Blue eye

  • C. Pink eye

  • D. Brown eye

  • E. All the above

  • Answer:C

  • Answer Explanation:
    Conjunctivitis also known as pink eye. Inflammation of conjunctiva is known as conjunctivitis. The symptoms are swelling and watering of the eyes. This type of infection spreads easily from one person to another.

Question – 13

13. Two elements are said to be isotones, if they have

  • A. Same atomic number and different mass number

  • B. Same number of nucleons

  • C. Same atomic number as well as mass number

  • D. Same neutron number and different proton number

  • E. Same number of protons

  • Answer:B

  • Answer Explanation:
    Two elements are said to be isotones, if they have same neutron number and different proton number. Example:7N15,8O15

Question – 14

14. Consider the given figure in static equilibrium. What is the value of tension T1?

  • A. 70.70 N

  • B. 50.70 N

  • C. 141.42 N

  • D. 35.35 N

  • E. 30 N

  • Answer:A

  • Answer Explanation:
    To find tension in the wire we need to resolve the forces along x and y direction.

    Since body is in equilibrium, total force along x-axis, Fx and total force along y-axis,
    Fy = 0. Total force acting along x-axis becomes
    T1cos45 = T2cos45
    T1 = T2
    And, total force for y-axis becomes
    T1sin45 + T2sin45 = 100N
    2 ?? T1sin45 = 100N
    T12  = 50N
    T1 = 70.7N
    Hence, option a is the correct answer

Question – 15

15. In which of the following organisms does fertilization occur externally?

  • A. Hydra

  • B. Frogs

  • C. Birds

  • D. Mammals

  • E. Both a and b

  • Answer:D

  • Answer Explanation:
    In hydra and frogs the fertilization occurs outside the body. Fertilization occurs internally in case of birds and mammals.

Score: 0/10

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