7th Science First Term Summative Assessment Question Paper with Answers 2024-25 | Villupuram District

7th Science First Term Summative Assessment Question Paper with Answers 2024-25 | Villupuram District

7th Science First Term Summative Assessment Question Paper with Answers 2024-25 | Villupuram District

7th Science First Term Exam Paper
FIRST TERM - SUMMATIVE ASSESSMENT(SA) - 2024-25

Class: 7

Subject: SCIENCE

Time Allowed: 2.00 Hours

Max. Marks: 60

I. Choose the correct answer. 10x1=10

1.Light year is the unit of

  • a) Distance
  • b) Time
  • c) Density
  • d) Both Length and Time
Answer: a) Distance

2.An element which is always Lustrous, Malleable and Ductile is

  • a) Non-metal
  • b) Metal
  • c) Metalloid
  • d) Gas
Answer: b) Metal

3.Which one of the following is an example for a metal.

  • a) Iron
  • b) Oxygen
  • c) Helium
  • d) Water
Answer: a) Iron

4.Oxygen, Hydrogen and Sulphur are examples for

  • a) Metals
  • b) Non-metals
  • c) Metalloids
  • d) Inert Gas
Answer: b) Non-metals

5.The metal which is liquid at room temperature is

  • a) Chlorine
  • b) Sulphur
  • c) Mercury
  • d) Silver
Answer: c) Mercury

6.The basic unit of Matter is __________

  • a) Element
  • b) Atom
  • c) Molecule
  • d) Electron
Answer: b) Atom

7.__________ is positively charged.

  • a) Proton
  • b) Electron
  • c) Molecule
  • d) Neutron
Answer: a) Proton

8.Vegetative Propagation by leaves takes place in

  • a) Bryophyllum
  • b) Fungi
  • c) Virus
  • d) Bacteria
Answer: a) Bryophyllum

9.Reproductive part of a Plant is

  • a) Root
  • b) Stem
  • c) Leaf
  • d) Flower
Answer: d) Flower

10.Climbing roots are seen in

  • a) Betel
  • b) Black pepper
  • c) Both of them
  • d) None of them
Answer: c) Both of them
II. Fill in the blanks: 10x1=10

11.Eyes are considered as windows to the world.

12.Tuberculosis is caused by the Bacterium Mycobacterium tuberculosis.

13.The male Reproductive part of a Flower is Androecium / Stamen.

14.After Fertilization the ovules becomes seeds.

15.Breathing Roots are seen in mangrove plants.

16.The smaller particles found in the atom are called sub-atomic particles.

17.Graphite is the only Non - metal which conducts electricity.

18.The smallest particle of matter that can exist by itself is molecule.

19.There are 118 number of known elements.

20.The Rate of Change of velocity is acceleration.

III. Match the following: 5x1=5
Question Correct Match
21. Displacement Metre
22. Light travelling through vacuum Uniform Velocity
23. Speed of Ship Knot
24. Centre of gravity of geometrical shaped objects Geometric centre
25. Stability Larger base area
IV. Answer any Ten questions: 10x2=20

26.What is One light year?

A light year is the distance that light travels in one year in a vacuum. It is equal to 9.46 x 1012 km.

27.Define - Astronomical Unit.

An astronomical unit (AU) is defined as the mean distance between the center of the Earth and the center of the Sun. 1 AU is approximately 149.6 million kilometers.

28.Length of Scale : metre :: Speed of Aeroplane : ?

Speed of Aeroplane : Knot

29.Define Molecule.

A molecule is the smallest particle of an element or a compound that can exist on its own and shows all the properties of that substance. It is formed when two or more atoms are chemically bonded together.

30.Write the Chemical formula for the following elements.

a) Hydrogen - H₂

b) Nitrogen - N₂

c) Ozone - O₃

d) Sulphur - S₈

31.Name the Sub - atomic particles.

The sub-atomic particles are:
  • Protons
  • Neutrons
  • Electrons

32.What are the Characteristics of Proton?

  • It is a positively charged particle.
  • It is located in the nucleus of an atom.
  • Its mass is approximately 1.672 x 10-27 kg.

33.What are the two important parts of a Flower.

The two important (essential) parts of a flower are:
  1. Androecium: The male reproductive part.
  2. Gynoecium: The female reproductive part.

34.Define Pollination.

Pollination is the process of transferring pollen grains from the anther (male part) of a flower to the stigma (female part) of the same or another flower.

35.What is Hygiene?

Hygiene refers to a set of practices performed to preserve health and prevent the spread of diseases. It includes personal hygiene (e.g., hand washing, bathing) and environmental hygiene.

36.Give any two Communicable diseases, which spread in your locality during Monsoon.

Two communicable diseases that commonly spread during monsoon are:
  1. Cholera
  2. Typhoid
(Other examples: Dengue, Malaria, Common Cold)

37.What first aid will you provide in the case of Bruises?

For a bruise, apply an ice pack or a cold compress wrapped in a cloth to the affected area for 15-20 minutes. This helps to reduce swelling, pain, and bleeding under the skin.
V. Answer briefly: (Any 3) 3x5=15

38.Write about any three Communicable diseases in detail.

1. Cholera:

  • Causative agent: Bacterium (Vibrio cholerae).
  • Mode of transmission: Spreads through contaminated food and water.
  • Symptoms: Severe diarrhoea, vomiting, and dehydration.
  • Prevention: Drinking boiled water, maintaining proper sanitation, and vaccination.

2. Tuberculosis (TB):

  • Causative agent: Bacterium (Mycobacterium tuberculosis).
  • Mode of transmission: Spreads through the air when an infected person coughs or sneezes (droplet infection).
  • Symptoms: Persistent cough, fever, weight loss, and night sweats.
  • Prevention: BCG vaccination, avoiding contact with infected persons, and maintaining good hygiene.

3. Common Cold:

  • Causative agent: Virus (Rhinovirus).
  • Mode of transmission: Spreads through droplets from coughing or sneezing and by touching contaminated surfaces.
  • Symptoms: Runny nose, sore throat, sneezing, and cough.
  • Prevention: Frequent hand washing, avoiding touching the face, and covering the mouth and nose while coughing or sneezing.

39.Write a brief account on Pollination.

Pollination is the act of transferring pollen grains from the male anther of a flower to the female stigma. The goal of every living organism, including plants, is to create offspring for the next generation. Pollination is the first step in this process for flowering plants.

Types of Pollination:

  1. Self-Pollination: The transfer of pollen grains from the anther to the stigma of the same flower or another flower on the same plant.
  2. Cross-Pollination: The transfer of pollen grains from the anther of one flower to the stigma of a flower on another plant of the same species.

Agents of Pollination:

Pollination is carried out by various agents:

  • Wind (Anemophily): Pollen is light and non-sticky, produced in large quantities (e.g., maize, pine).
  • Water (Hydrophily): Occurs in aquatic plants (e.g., Vallisneria, Hydrilla).
  • Insects (Entomophily): Flowers are often large, colourful, fragrant, and rich in nectar to attract insects like bees and butterflies.
  • Animals (Zoophily): Birds, bats, and other animals help in pollination.

40.Draw the Structure of an Atom and Explain the position of the sub - atomic particles.

Structure of an Atom:

Structure of an Atom

Position of Sub-atomic Particles:

An atom consists of a central nucleus and surrounding electrons. The positions are as follows:

  • Nucleus: This is the dense, central core of the atom. It contains two types of sub-atomic particles:
    • Protons: They are positively charged particles.
    • Neutrons: They have no charge (they are neutral).
    The nucleus holds almost the entire mass of the atom and has an overall positive charge.
  • Electron Shells/Orbits:
    • Electrons: They are negatively charged particles that revolve around the nucleus in fixed, circular paths called orbits or shells. Electrons are very light compared to protons and neutrons. The number of electrons is equal to the number of protons in a neutral atom.

41.Differentiate Metals and Non - Metals.

Property Metals Non-Metals
Lustre They have a shiny surface (lustrous). They have a dull appearance (non-lustrous), except for iodine and graphite.
Hardness Generally hard and strong (except sodium, potassium). Generally soft (except diamond).
State Solid at room temperature (except mercury). Exist as solids, liquids, or gases at room temperature.
Malleability Can be beaten into thin sheets. Cannot be beaten into thin sheets (brittle).
Ductility Can be drawn into thin wires. Cannot be drawn into wires (non-ductile).
Conduction Good conductors of heat and electricity. Poor conductors of heat and electricity (except graphite).

42.Write about the experiment to find the Centre of Gravity of the irregularly shaped plate.

Aim: To find the centre of gravity of an irregularly shaped lamina using a plumb line.

Materials Required: Irregularly shaped lamina (cardboard), retort stand, plumb line, pin, and pencil.

Procedure:

  1. Make three small holes near the edge of the lamina and label them A, B, and C.
  2. Suspend the lamina freely from hole A using the pin from the retort stand.
  3. Hang the plumb line from the same pin and wait for it to come to rest.
  4. Draw a straight line (AD) on the lamina along the thread of the plumb line.
  5. Repeat the experiment by suspending the lamina from hole B. Draw another line (BE) along the plumb line.
  6. Again, repeat the process by suspending the lamina from hole C and draw a third line (CF).

Observation: You will observe that all three lines (AD, BE, and CF) intersect at a common point.

Conclusion: The point of intersection, G, is the centre of gravity of the irregularly shaped lamina.