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CLASS 8 SCIENCE TERM 2 LESSONS ONE MARK QUESTIONS AND ANSWERS
STANDARD - VIII
SCIENCE
Term - II Lessons - One Mark Questions & Answers
Choose the best answer.
1. Sound waves travel very fast in
Ans: b) metals
2. Which of the following are the characteristics of vibrations?
i. Frequency ii. Time period iii. Pitch iv. Loudness
Ans: a) i and ii
3. The amplitude of the sound wave decides its
Ans: c) loudness
4. What kind of musical instrument is a sitar?
Ans: a) String instrument
5. Find the odd one out.
a) Harmonium
b) Flute
c) Nadaswaram
d) Violin
Ans: d) Violin
6. Noise is produced by
Ans: d) irregular and non-periodic vibrations.
7. The range of audible frequency for the human ear is
Ans: c) 20 Hz to 20000 Hz
8. If the amplitude and frequency of a sound wave are increased, which of the following is true?
Ans: a) Loudness increases and pitch is higher.
9. Which of the following may be caused by noise?
a) Irritation
b) Stress
c) Nervousness
d) All the above
Ans: d) All the above
1. When an ebonite rod is rubbed with fur, the charge acquired by the fur is
Ans: b) positive
2. The electrification of two different bodies on rubbing is because of the transfer of
Ans: c) electrons
3. Which of the following a simple circuit must have?
Ans: d) Battery, Wire, Switch
4. An electroscope has been charged by induction with the help of charged glass rod. The charge on the electroscope is
Ans: b) positive
5. Fuse is
Ans: d) a protective device for breaking an electric circuit
1. The same proportion of carbon and oxygen in the carbon dioxide obtained from different sources proves the law of __________
Ans: b) definite proportion
2. Cathode rays are made up of
Ans: c) negatively charged particles
3. In water, hydrogen and oxygen are combined in the ratio of _______by mass.
Ans: a) 1:8
4. Which of the following statements made by Dalton has not undergone any change?
Ans: c) Elements are made up of atoms.
5. In all atoms of an element
Ans: c) the atomic number is same and the mass number is different
1. Water changes to ice at __________________
Ans: a) 00C
2. Solubility of carbon dioxide in water is high when the ____________
Ans: b) pressure is high
3. The gas collected at the cathode on electrolysis of water is
Ans: b) hydrogen
4. Which of the following is a water pollutant?
Ans: a) Lead
5. Permanent hardness of water is due to the presence of __________
Ans: a) sulphates and chlorides
1. Acids are ________ in taste.
Ans: a) sour
2. Aqueous solutions of _________ conduct electricity.
Ans: c) salt
3. In acidic solutions blue litmus changes into ______ colour.
Ans: c) red
4. Base is a substance that gives _____ on dissolving in water.
Ans: a) OH-
5. Sodium hydroxide is a ____________
Ans: b) base
6. Red ant sting contains __________
Ans: d) formic acid
7. Magnesium hydroxides are used for treating_______
Ans: a) acidity
8. Acid mixed with base forms ________
Ans: a) salt and water
9. We brush our teeth with toothpaste because it is __________ in nature.
Ans: a) basic
10. In basic solution turmeric indicator paper changes from yellow to __________
Ans: d) red
1. Which of the following parts of our body help us in movement?
(i) Bones (ii) Skin (iii) Muscles (iv) Organs
Choose the correct answer from the options below.
(a) (i) and (iii)
(b) (ii) and (iv)
(c) (i) and (iv)
(d) (iii) and (ii)
Ans: (a) (i) and (iii)
2. Which one of the following organisms lack muscles and skeleton for movement?
Ans: (c) Earthworm
3. __________ joints are immovable.
Ans: (c) Upper jaw and skull
4. Why do underwater divers wear fin-like flippers on their feet ?
Ans: (a) To swim easily in water
5. External ear (pinna )is supported by
Ans: (b) cartilage
6. Cockroach moves with the help of its
Ans: (a) leg
7. Which one of the following categories of vertebrae are correctly numbered?
Ans: (a) Cervical-7
1. Adolescence is the period of life between _____________ years of age.
Ans: c) 11 to 19
2. The period at which an organism attains sexual maturity is called _____________
Ans: a) puberty
3. During puberty, the region below the waist become wider in _____________
Ans: b) girls
4. Adam’s apple is the growth of the ________
Ans: c) larynx
5. Many adolescent boys and girls get pimples on face, due to the secretions of _________
Ans: c) sweat and sebaceous
6. The sperm is produced by ____________
Ans: d) testes
7. ___________ are the chemical substances, secreted by endocrine glands.
Ans: a) Hormones
8. Androgen production is regulated by ___________
Ans: b) LH hormone
9. During menstruation, the progesterone level is ___________
Ans: c) ceased
10. ___________ intake needs to be increased to prevent osteoporosis in later life.
Ans: d) Calcium
Fill in the blanks.
1. Sound is produced by __________.
Ans: vibrating bodies
2. The vibrations of a simple pendulum are also known as __________.
Ans: oscillation
3. Sound travels in the form of _________.
Ans: mechanical wave
4. High frequency sounds that cannot be heard by you are called _________.
Ans: ultrasonics
5. Pitch of a sound depends on the ________ vibration.
Ans: frequency of the
6. If the thickness of a vibrating string is increased, its pitch __________.
Ans: decreases
1. _____takes place by rubbing objects together.
Ans: charging
2. The body which has lost electrons becomes ________.
Ans: positively charged
3. ________ is a device that protects building from lightning strike.
Ans: Lightning arrester
4. ________ has a thin metallic filament that melts and breaks the connection when the circuit is overheated.
Ans: A fuse wire
5. Three bulbs are connected end to end from the battery. This connection is called ________.
Ans: series circuit
1. ____________ is the smallest particle of an element.
Ans: Atom
2. An element is composed of ____________ atoms.
Ans: only one type of
3. An atom is made up of ____________, ____________ and ____________.
Ans: electrons, protons and neutrons
4. A negatively charged ion is called ____________, while positively charged ion is called ____________.
Ans: anion, cation
5. ____________ is a negatively charged particle (Electron/Proton).
Ans: Electron
6. Proton is deflected towards the _________ charged plate (positively, negatively).
Ans: negatively
1. Water is colourless, odourless and __________.
Ans: tasteless
2. The boiling point of water is __________
Ans: 100°C
3. Temporary hardness of water can be removed by __________ of water.
Ans: boiling
4. The density of water is maximum at __________.
Ans: 4°C
5. Loading speeds up the process of __________.
Ans: sedimentaion
1. Benzoic acids are used for ___________
Ans: food preservation.
2. The word sour refers to __________ in Latin.
Ans: acidus
3. Bases are _____________ in taste.
Ans: bitter
4. Chemical formula of calcium oxide is _______
Ans: CaO
5. Wasp sting contains __________
Ans: formic acid.
6. Turmeric is used as a__________
Ans: natural indicator.
7. In acidic solution the colour of the hibiscus indicator paper will change to _____
Ans: pink
1. Movement of organisms from place to place is called __________.
Ans: locomotion
2. __________ refers to change in position of the part of an organism’s body.
Ans: Movement
3. A structure which provides rigid frame work to the body is called __________
Ans: skeleton
4. Axil skeleton in human consists of __________, __________, __________ and __________.
Ans: skull, ribs, sternum, and vertebral column
5. Appendicular skeleton in human consists of __________ and __________.
Ans: Pectoral Girdle and Pelvic Girdle
6. The place where two bones meet is termed as __________.
Ans: Joint
7. __________ is attached to soft parts of the body like blood vessels, iris, bronchi and the skin
Ans: Non striated muscle
8. __________ muscle makes pupil of eyes wider.
Ans: Radial
1. ____________ is secreted by the ovaries of females.
Ans: Estrogen
2. The hormones secreted by the gonads are controlled by __________.
Ans: anterior pituitary
3. Milk secretion during lactation is controlled by ____________ hormone.
Ans: Prolactin
4. The male and the female gamete fuse together and form ____________.
Ans: zygote
5. The first menstrual flow begins at puberty and it is termed as ______________.
Ans: menarche
6. _____________ usually occurs 14 days after ovulation.
Ans: Mensuration
7. _____________ includes protein, carbohydrates, fats and vitamins in requisite proportion.
Ans: Balanced diet
8. ____________ helps to prevent thyroid gland related diseases.
Ans: Iodine
9. Iron deficiency leads to ____________.
Ans: anemia
10. In women fertilization takes place at ___________.
Ans: fallopian tube
True or False. If False, give the correct statement
1. The charge acquired by an ebonite rod rubbed with a piece of flannel is negative.
Ans: True
2. A charged body induces an opposite charge on an uncharged body when they are brought near.
Ans: False
Correct Statement: An uncharged body acquires an opposite charge at the near end and similar charge at the farther end.
3. Electroscope is a device used to charge a body by induction.
Ans: True
4. Water can conduct electricity.
Ans: True
5. In parallel circuit, current remains the same in all components.
Ans: False.
Correct Statement: In parallel circuit, voltage across the resistors remains the same but the current flowing through the circuit gets divided across each resistor.
1. Sewage should be treated well before being discharged into water bodies.
Ans: True
2. Sea water is suitable for irrigation as it contains dissolved salts.
Ans: False.
Sea water is not suitable for irrigation as it contains dissolved salts.
3. Excessive use of chemical fertilizers depletes the soil and causes water pollution.
Ans: True
4. The density of water will not change at all temperatures?
Ans: False.
Density of water varies at different temperatures.
5. Soap lathers well in hard water.
Ans: False.
Soap lathers well in soft water.
1. Most of the acids are not soluble in water.
Ans: False
Most of the acids are soluble in water.
2. Acids are bitter in taste.
Ans: False
Acids are sour in taste.
3. Bases are soapy to touch when they are dry.
Ans: False
Bases are soapy to touch only in aqueous medium.
4. Acids are corrosive in nature.
Ans: True
5. All bases are alkalis.
Ans: False
All alkalis are bases but all bases are not alkalis.
6. Hibiscus flower is an example for natural indicator.
Ans: True
1. Skull in humans consists of 22 bones.
Ans: True
2. There are 12 pairs of ribs in human body.
Ans: True
3. Pelvic girdle is a part of axial skeleton.
Ans: False
Pelvic girdle is a part of appendicular skeleton.
4. Hinge joint is slightly movable joint.
Ans: False
Hinge joint is freely movable joint.
5. Cardiac muscle is a voluntary muscle.
Ans: False
Cardiac muscle is an involuntary muscle.
6. The flexor and extensor muscle of the arm are antagonistic muscles.
Ans: True
1. There is a sudden increase in the height of both boys and girls during puberty.
Ans: True
2. The release of ovum from the uterus is called ovulation.
Ans: False
The release of ovum from one of the ovaries is called ovulation.
3. During pregnancy, the corpus luteum continues to grow and produces large
amount of estrogen and progesterone.
Ans: True
4. Making use of disposable napkins or tampons may increase the chances of
infections.
Ans: False
Making use of disposable napkins or tampons may reduce the chances of infections.
5. Using clean toilets for defecation is a good practice.
Ans: True
Match the following:
