Board Paper of Class 10 2017 Biology - Solutions

• Question 16
  The inheritable characters vary in different species and within the same species. Name the variation in the following cases.
  
  (i) The eye colour among the human beings are varied as blue, black, brown, green etc. This is called as __________ variation.
  
  (ii) The dentition in the rabbit and the elephant are not the same. This is called as __________ variation. VIEW SOLUTION

• Question 17
  What is Genetic Engineering ? VIEW SOLUTION

• Question 18
  Match the following by identifying the pair :
  
  (medicines, fuel, microbes, metabolism, organic acids)
  
  (i) Vaccine, (ii) Natural gas, (iii) Citric acid, (iv) Vitamins VIEW SOLUTION

• Question 19
  Marasmus and Kwashiorkar are both protein deficiency defects. Marasmus differs from Kwashiorkar in enlarged belly and swelling in the face. Are these symptoms for the above diseases correct ? If not, correct it. VIEW SOLUTION

• Question 20
  Copy the diagram and label the parts with the help of the clues given :
  
  
  
  
  (i) It is otherwise called supra renal gland.
  
  (ii) It secretes two hormones, namely aldosterone and cortisone. VIEW SOLUTION

• Question 21
  Draw the given diagram and label the following parts.
  
  (i) Exine
  
  (ii) Tube nucleus
  
  VIEW SOLUTION

• Question 22
  Mention any four adaptations seen in the camel so that it can live successfully in deserts. VIEW SOLUTION

• Question 23
  Pick out the odd one out.
  
  (i) globulin, glomerulus, fibrinogen, albumin
  
  (ii) mountain goat, big horned sheep, grizzly bear, seal VIEW SOLUTION

• Question 24
  Complete the table given below :
   

  Excretory organ	Disposed as	Excretory products
  Kidneys	Urine	Nitrogenous waste products - Urea, Uric acid, Creatinine etc.
  Lungs	Exhaled/Expired air	__________
  Skin	__________	Excess water and salts

  VIEW SOLUTION

• Question 25
  Observe the diagram.
  
  
  
  
  (i) Mention the type of movements shown in figure A and B.
  
  (ii) How does this movement differ from the movement of mimosa ? VIEW SOLUTION

• Question 26
  Sugar solution is converted into alcohol.
  
  (i) In the above reaction what kind of process takes place?
  
  (ii) Which micro - organism is involved ? VIEW SOLUTION

• Question 27
  Match the following :

  	A		B
  (a)	Ammonotelic	(i)	annelids
  (b)	Ureotelic	(ii)	fish
  (c)	Uricotelic	(iii)	mammal
  (d)	Nephridia	(iv)	birds

  VIEW SOLUTION

• Question 28
  Depict a food chain by placing the following organisms in the correct trophic levels.
  
  (Snake, Grass, Eagle, Frog, Grasshopper) VIEW SOLUTION

• Question 29
  What are the various liquid biofuels for transportation ?   (Any four) VIEW SOLUTION

• Question 30
  Match the suitable renewable and non-renewable sources.
   

  Sources	A	B	C
  Renewable	Coal	Wind	Petroleum
  Non - Renewable	Hydrogen	Natural gas	Solar energy

  VIEW SOLUTION

• Question 31
  Fossil fuels are formed by decomposition of biomass buried under the earth over millions of years ago. Name any two fossil fuels. VIEW SOLUTION

• Question 32
  What is Brownian movement ? VIEW SOLUTION

• Question 33
  Find the concentration of solution in terms of weight percent if 20 g of common salt is dissolved in 50 g of water. VIEW SOLUTION

• Question 34
  Calculate the number of moles in 12.046 × 10²² atoms of copper. VIEW SOLUTION

• Question 35
  Two acids ‘A’ and ‘B’ were kept in beakers. Acid ‘A’ undergoes partial dissociation in water, whereas acid ‘B’ undergoes complete dissociation in water.
  
  (i) Of the two acids ‘A’ and ‘B’. Which is weak acid and which is strong acid ?
  
  (ii) Give one example for weak acid and strong acid. VIEW SOLUTION

• Question 36
  Pick the odd one out :
  
  (i) Inorganic acids : HCl, HNO₃, H₂SO₄, HCOOH
  
  (ii) Basic Nature : Blood, Baking Soda, Vinegar, Household ammonia VIEW SOLUTION

• Question 37
  Correct the mistakes, if any in the following statement.
  
  (i) Second period is a short period. It contains only two elements.
  
  (ii) Group 18 elements are called Halogen family. VIEW SOLUTION

• Question 38
  Assertion : A greenish layer appears on copper vessels, if left uncleaned.
  Reason : It is due to the formation of a layer of basic copper carbonate.
  (a) Assertion and reason are correct and relevant to each other.
  (b) Assertion is true but reason is not relevant to the assertion. VIEW SOLUTION

• Question 39
  An organic compound (A) is widely used as a preservative in pickle and has a molecular formula C₂H₄O₂. This compound reacts with ethanol to form a sweet smelling compound (B).
  
  (i) Identify the compounds A and B.
  
  (ii) Name the process and write the corresponding chemical equation. VIEW SOLUTION

• Question 40
  Assertion (A) : MRI is used to scan the inner organs of human body by penetrating very intense magnetic field.
  Reason (R) : By use of very intense magnetic field, very high resolution images can be obtained.
  (a) (A) is incorrect and (R) is correct.
  (b) (A) is correct and (R) is incorrect.
  (c) Both (A) and (R) are incorrect.
  (d) (A) is correct and (R) supports (A). VIEW SOLUTION

• Question 41
  An object of mass 1 kg is dropped from a height of 20 m. It hits the ground and rebounds with the same speed. Find the change in momentum
  (Take g = 10 m/s²) VIEW SOLUTION

• Question 42
  Match the following :

  	COMPONENTS		SYMBOLS
  (a)	An electric cell	(i)
  (b)	Plug key (or) switch (closed)	(ii)
  (c)	A wire joint	(iii)
  (d)	A resistor of resistance R	(iv)

  VIEW SOLUTION

• Question 43
  Fill in the blanks :
  
  (i) Potential difference : Voltmeter ; then Current : ___________
  
  (ii) Hydro power plant : Conventional source of energy ; then Solar energy : __________ VIEW SOLUTION

• Question 44
  Write about ocean thermal energy. VIEW SOLUTION

• Question 45
  The ray diagram shown below is introduced to show how a concave mirror forms the image of an object.
  
  (a) Identify the mistake and draw the correct ray diagram.
  
  (b) Write the justifications for your corrections.
  
  VIEW SOLUTION

• Question 46
  Define Fleming’s right hand rule. VIEW SOLUTION

• Question 47
  If an object is placed 25 cm in front of the converging lens forms an image 20 cm behind the lens, then what is the focal length of the lens? VIEW SOLUTION

• Question 48
  There is a widespread outbreak of malaria in your area.
  
  (a) Suggest some controlling measures to the local authorities concerned.
  
  (b) Write the symptoms for malaria. VIEW SOLUTION

• Question 49
  (a) Use words from the given list to complete the following paragraph.

  (Vertebral column, Piamater, Arachnoid membrane, Meninges, Duramater)
  The central nervous system is covered by three protective coverings collectively called   (1)  . The outermost cover lying below the skull and   (2)   is double thick and is called    (3)   . The middle covering is thin and vascularised and is called   (4)   . The innermost cover is a very thin delicate membrane and is closely stretched over the outer surface of Brain and Spinal Cord and is called   (5)   .

  
  (b) Name any 5 types of nerve cells. VIEW SOLUTION

• Question 50
  Describe the structure of a dicot seed with a neat diagram. VIEW SOLUTION

• Question 51
  (a) What is Green Chemistry ?
  
  (b) Write the future products of Green Chemistry. VIEW SOLUTION

• Question 52
  Modern atomic theory takes up the wave concept, principle of uncertainty and other latest discoveries to give a clear cut picture about an atom. State the findings of modern atomic theory. VIEW SOLUTION

• Question 53
  Explain the manufacturing of Ethanol from Molasses. VIEW SOLUTION

• Question 54
  (a) Newton’s first law of motion gives a qualitative definition of force. Justify.
  
  (b) The figure represents two bodies of masses 10 kg and 15 kg, moving with an initial velocity of 10 ms⁻¹ and 5 ms⁻¹ respectively. They collide with each other. After collision, they move with velocities 4 ms⁻¹ and 9 ms⁻¹ respectively. The time of collision is 2 s. Now calculate F₁ and F₂.
  
  VIEW SOLUTION

• Question 55
  State and explain the defects of vision. How can these defects be rectified ? VIEW SOLUTION