Teeth and the World of Microbes
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Types and Structure of Teeth
SubtopicTypes and Structure of Teeth under Teeth and the World of Microbes for Grade 4 CBSE.
Preview questions (no answers)
- 1.
Which of the following describes the function of canines?
A.Biting and cutting
B.Tearing and gripping
C.Grinding and pasting
D.Chewing and crushing
- 2.
Which type of teeth are used for crushing and grinding food?
A.Incisors only
B.Canines and Incisors
C.Premolars and Molars
D.Only Canines
- 3.
Why is it important to rinse your mouth after eating?
A.To make the teeth shine
B.To remove food particles stuck between teeth
C.To change the color of the gums
D.To make the pulp hard
- 4.
Which of these is NOT a type of microbe?
A.Bacteria
B.Fungi
C.Insects
D.Protozoa
- 5.
How often should we ideally visit a dentist for a check-up?
A.Every month
B.Every six months
C.Once in two years
D.Only when we have a toothache
- 6.
Which teeth are known as 'cracking teeth' because they help in cracking hard food like nuts?
A.Incisors
B.Canines
C.Premolars
D.Wisdom teeth
- 7.
What is the main function of the dentine layer in a tooth?
A.To produce blood
B.To act as a support for the enamel
C.To sense the taste of food
D.To hold the tooth in the socket
- 8.
Identify the number of incisors in a child who has just started getting their milk teeth and has only the front bottom and front top teeth.
A.2
B.4
C.8
D.0
- 9.
Which tooth type has a single sharp point or cusp?
A.Incisor
B.Molar
C.Canine
D.Premolar
- 10.
How many teeth in a permanent set of 32 do NOT have a matching milk tooth predecessor (teeth that grow in space where no milk tooth was before)?
A.8 teeth
B.20 teeth
C.12 teeth
D.4 teeth
Download the worksheet for Teeth and the World of Microbes - Types and Structure of Teeth to practice offline. It includes additional chapter-level practice questions.
Dental Care and Hygiene
SubtopicDental Care and Hygiene under Teeth and the World of Microbes for Grade 4 CBSE.
Preview questions (no answers)
- 1.
What should we use to clean our tongue?
A.Toothpick
B.Tongue cleaner
C.Finger nail
D.Hard brush
- 2.
Which disease is caused by bacteria?
A.Flu
B.Tuberculosis
C.Measles
D.Chickenpox
- 3.
Which teeth are mainly used for biting into an apple?
A.Molars
B.Incisors
C.Premolars
D.Wisdom teeth
- 4.
Microbes grow very fast in which of these conditions?
A.Dry and cold
B.Warm and moist
C.Freezing and dark
D.Hot and dry
- 5.
What is the role of bacteria in the large intestine of humans?
A.They cause diseases
B.They help in the digestion of food
C.They weaken the immune system
D.They prevent the absorption of water
- 6.
Which microbe is responsible for causing the disease called 'Flu'?
A.Bacteria
B.Virus
C.Fungi
D.Protozoa
- 7.
Which of the following can lead to the formation of tooth decay?
A.Regular flossing
B.Eating too many sweets and chocolates
C.Rinsing the mouth with water
D.Drinking plenty of water
- 8.
Which type of tooth is specifically shaped like a chisel and is used for cutting food into smaller pieces?
A.Molar
B.Canine
C.Incisor
D.Premolar
- 9.
Which of the following would be the most effective way to prevent the spread of viral diseases like the common cold?
A.Taking calcium supplements.
B.Brushing your teeth three times a day.
C.Washing hands frequently and covering the mouth while sneezing.
D.Eating more sugar for energy.
- 10.
If a dentist finds a 'filling' is necessary, what has happened to the tooth?
A.The tooth has grown too large for the jaw.
B.The enamel and dentin have been destroyed by acid, creating a hole.
C.The milk tooth is refusing to fall out.
D.The tooth has changed from a molar to an incisor.
Download the worksheet for Teeth and the World of Microbes - Dental Care and Hygiene to practice offline. It includes additional chapter-level practice questions.
Microbes: Useful and Harmful
SubtopicMicrobes: Useful and Harmful under Teeth and the World of Microbes for Grade 4 CBSE.
Preview questions (no answers)
- 1.
What gives spoiled food a bad smell and taste?
A.Fresh air
B.Growth of microbes
C.Cold water
D.Clean containers
- 2.
Which of these actions helps to stop microbes from growing on our skin?
A.Not bathing for a week
B.Taking a bath daily
C.Playing in mud all day
D.Wearing dirty clothes
- 3.
Which of these microbes is used to produce bubbles of carbon dioxide that make bread soft?
A.Bacteria
B.Yeast
C.Amoeba
D.Virus
- 4.
If you look at a drop of pond water under a microscope, you might see tiny moving organisms called:
A.Protozoa
B.Trees
C.Fishes
D.Birds
- 5.
Which of these is the most effective way to prevent the spread of water-borne microbes?
A.Leaving water in open containers
B.Drinking filtered or boiled water
C.Adding sugar to the water
D.Storing water in a dark room
- 6.
Dysentery is a condition that causes stomach pain and loose motions. It is primarily caused by which microbe?
A.Bacteria or Protozoa
B.Only Viruses
C.Only Fungi
D.Mushrooms
- 7.
If you look at a drop of stagnant pond water under a microscope, which microbe are you most likely to see moving around?
A.Yeast
B.Protozoa
C.Mushrooms
D.Bread mold
- 8.
Based on the sequence of tooth decay shown in the diagram, why is a person likely to feel no pain during Stage V (Enamel Damage), but experience intense pain at Stage X (Pulp Infection)?
A.The Enamel in Stage V has no nerves, whereas the Pulp in Stage X contains the tooth's nerves and blood vessels.
B.Microbes only produce acid once they reach Stage X, making the infection more painful then.
C.The tooth's nerves are located on the surface of the Enamel and die off before the decay reaches Stage X.
D.Stage V is caused by harmless bacteria, while Stage X is caused by harmful viruses that enter the tooth.
- 9.
In the nutrient cycle shown below, if the organisms at stage C were completely removed from an environment, what would be the most likely long-term consequence for the plants at stage A?
A.The plants would grow much faster because there are no microbes to compete for water.
B.The plants would eventually die because the soil would run out of essential minerals and nutrients.
C.The plants would stop producing waste and dead leaves to prevent the environment from getting dirty.
D.The plants would start absorbing nutrients directly from the air instead of the soil.
- 10.
How do some microbes help in keeping the environment clean apart from decomposing dead matter?
A.By producing plastic
B.By cleaning oil spills in the ocean
C.By turning sunlight into food for all animals
D.By increasing the temperature of the Earth
Download the worksheet for Teeth and the World of Microbes - Microbes: Useful and Harmful to practice offline. It includes additional chapter-level practice questions.