Science

859 questions

📄 GuideIf many organisms share common features, could they also share a common ancestry? Class 9

If many organisms share common features, could they also share a common ancestry? Class 9Pause and P

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Class 9 Science

📄 GuideOn what basis are plants and animals classified? Class 9

On what basis are plants and animals classified? Class 9Question 1. On what basis are plants and ani

82 views
Class 9 Science

📄 GuideWhat do you understand by biodiversity? Class 9

What do you understand by biodiversity? Class 9Think It Over (Page 228)Question 1. What do you under

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Class 9 Science

📄 GuideActivity 12.9 Let us study the salient features of each plant group. Class 9

Activity 12.9 Let us study the salient features of each plant group. Class 9Activity 12.9 Let us stu

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Class 9 Science

📄 GuideActivity 12.8 Let us discuss to study different leaves, observe their shape and venation. Class 9

Activity 12.8 Let us discuss to study different leaves, observe their shape and venation. Class 9Act

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Class 9 Science

📄 GuideActivity 12.7 Let us compare to compare the cross section of a fern stem. Class 9

Activity 12.7 Let us compare to compare the cross section of a fern stem. Class 9Activity 12.7 Let u

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Class 9 Science

📄 GuideActivity 12.6 Let us explore to observe bryophytes and compare them with the leave. Class 9

Activity 12.6 Let us explore to observe bryophytes and compare them with the leave. Class 9Activity

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Class 9 Science

📄 GuideActivity 12.5 Let us make to prepare a hay infusion and observe microorganisms. Class 9

Activity 12.5 Let us make to prepare a hay infusion and observe microorganisms. Class 9Activity 12.5

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Class 9 Science

📄 GuideActivity 12.4 Let us explore to observe different shapes of bacteria and cyanobacteria. Class 9

Activity 12.4 Let us explore to observe different shapes of bacteria and cyanobacteria. Class 9Activ

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Class 9 Science

📄 GuideActivity 12.3 Let us study the concept map. Class 9

Activity 12.3 Let us study the concept map. Class 9Activity 12.3 Let us StudyQuestion 1. Study the c

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Class 9 Science

📄 GuideActivity 12.2 Let Us Read A Case Study. The Pakke Tiger Reserve in Arunachal Pradesh is a forest. Class 9

Activity 12.2 Let Us Read A Case Study. The Pakke Tiger Reserve in Arunachal Pradesh is a forest. Cl

87 views
Class 9 Science

📄 GuideActivity 12.1 Let us compare and classify Fig. shows the diversity of animals in an ecosystem. Class 9

Activity 12.1 Let us compare and classify Fig. shows the diversity of animals in an ecosystem. Class

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Class 9 Science

📄 GuideA student claims, “In humans, ovulation always happens on day 14 of the menstrual cycle”. Class 9

A student claims, “In humans, ovulation always happens on day 14 of the menstrual cycle”. Class 9Que

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Class 9 Science

📄 GuideIn the lower Himalayan region of northern India, apples are an important cash crop. Class 9

In the lower Himalayan region of northern India, apples are an important cash crop. Class 9Question

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Class 9 Science

📄 GuideLook at the picture given below and think in line with the given prompts. Class 9

Look at the picture given below and think in line with the given prompts. Class 9Question 1. Look at

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Class 9 Science

📄 GuideSuresh prepares slides with pollen grains in different sugar concentrations. Class 9

Suresh prepares slides with pollen grains in different sugar concentrations. Class 9Question 1. Sure

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Class 9 Science

📄 GuideA farmer wants to produce a large number of genetically identical plants quickly. Class 9

A farmer wants to produce a large number of genetically identical plants quickly. Class 9Question 1.

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Class 9 Science

📄 GuideIf all flowers in a type of plant were only capable of self-pollination. Class 9

If all flowers in a type of plant were only capable of self-pollination. Class 9Question 1. If all f

90 views
Class 9 Science

📄 GuideWhy are flowers that bloom at night white or light in colour as compared to flowers. Class 9

Why are flowers that bloom at night white or light in colour as compared to flowers. Class 9Question

87 views
Class 9 Science

📄 GuideWhy does asexual reproduction produce offsprings that are genetically identical to the parent? Class 9

Why does asexual reproduction produce offsprings that are genetically identical to the parent? Class

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Class 9 Science

📄 GuideThe zygote formed after fertilisation immediately attaches to the uterus wall. Class 9

The zygote formed after fertilisation immediately attaches to the uterus wall. Class 9Question 1. As

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Class 9 Science

📄 GuideA flower’s anthers are removed before it matures. Later, pollen from another plant. Class 9

A flower’s anthers are removed before it matures. Later, pollen from another plant. Class 9Revise, R

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Class 9 Science

📄 GuideIn many animals, the young ones can walk or find food soon after birth. Class 9

In many animals, the young ones can walk or find food soon after birth. Class 9(Page 224)Question 1.

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Class 9 Science

📄 GuideIf a couple uses oral contraceptive pills but not condoms, which risks remain and why? Class 9

If a couple uses oral contraceptive pills but not condoms, which risks remain and why? Class 9Questi

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Class 9 Science

📄 GuideWhat protective devices can be used during sexual activity to reduce the spread of STIs? Class 9

What protective devices can be used during sexual activity to reduce the spread of STIs? Class 9(Pag

75 views
Class 9 Science

📄 GuideRavi suddenly notices that he is growing taller rapidly, his shoulders are broadening. Class 9

Ravi suddenly notices that he is growing taller rapidly, his shoulders are broadening. Class 9(Page

80 views
Class 9 Science

📄 GuideA farmer plants two varieties of maize side by side, but notices that seeds. Class 9

A farmer plants two varieties of maize side by side, but notices that seeds. Class 9Question 1. A fa

82 views
Class 9 Science

📄 GuideIn a china-rose (hibiscus or gudhal) plant, a pollen tube grows and continues. Class 9

In a china-rose (hibiscus or gudhal) plant, a pollen tube grows and continues. Class 9Pause and Pond

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Class 9 Science

📄 GuideMoulds on bread may look unpleasant but fungi benefit society greatly. Class 9

Moulds on bread may look unpleasant but fungi benefit society greatly. Class 9Bridging Science and S

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Class 9 Science

📄 GuideWhen does a farmer prefer asexual or sexual methods of reproduction for crops production? Class 9

When does a farmer prefer asexual or sexual methods of reproduction for crops production? Class 9Thi

74 views
Class 9 Science

📄 GuideActivity 11.7 Let us find out to compare different pollination strategies. Class 9

Activity 11.7 Let us find out to compare different pollination strategies. Class 9Activity 11.7 Let

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Class 9 Science

📄 GuideActivity 11.6 Let us investigate to study the role of pollination in fruit. Class 9

Activity 11.6 Let us investigate to study the role of pollination in fruit. Class 9Activity 11.6 Let

73 views
Class 9 Science

📄 GuideActivity 11.5 Let us explore to observe and identify the different parts of flowers. Class 9

Activity 11.5 Let us explore to observe and identify the different parts of flowers. Class 9Activity

86 views
Class 9 Science

📄 GuideHow many combinations can you make with just these three pairs of characters? Class 9

How many combinations can you make with just these three pairs of characters? Class 9Question 1. How

80 views
Class 9 Science

📄 GuideActivity 11.4 Let us explore to determine how many unique combinations of characters. Class 9

Activity 11.4 Let us explore to determine how many unique combinations of characters. Class 9Activit

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Class 9 Science

📄 GuideActivity 11.3 Let us experiment to study growth of bread mould, fungus (Rhizopus). Class 9

Activity 11.3 Let us experiment to study growth of bread mould, fungus (Rhizopus). Class 9Activity 1

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Class 9 Science

📄 GuideActivity 11.2 Let us explore to study the process of budding in yeast. Class 9

Activity 11.2 Let us explore to study the process of budding in yeast. Class 9Activity 11.2 Let us e

115 views
Class 9 Science

📄 GuideActivity 11.1 Let us explore to study and observe the methods of vegetative propagation. Class 9

Activity 11.1 Let us explore to study and observe the methods of vegetative propagation. Class 9Acti

90 views
Class 9 Science

📄 GuideTwo identical sound sources are placed at A and B—one in air and one submerged in water. Class 9

Two identical sound sources are placed at A and B—one in air and one submerged in water. Class 9Ques

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Class 9 Science

📄 GuideThe graphical representation of two sound waves A and B propagating at the same speed. Class 9

The graphical representation of two sound waves A and B propagating at the same speed. Class 9Questi

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Class 9 Science

📄 GuideThe speed of sound in air is about 331 m s-1 at 0 °C and nearly 344 m s-1 at 22 °C. Class 9

The speed of sound in air is about 331 m s-1 at 0 °C and nearly 344 m s-1 at 22 °C. Class 9Question

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Class 9 Science

📄 GuideA ship searching for a sunken ship sent a sonar signal and detected an echo after 5 s. Class 9

A ship searching for a sunken ship sent a sonar signal and detected an echo after 5 s. Class 9Questi

78 views
Class 9 Science

📄 GuideIn a movie, while showing the explosion of a spacecraft in space, a flash of light. Class 9

In a movie, while showing the explosion of a spacecraft in space, a flash of light. Class 9Question

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Class 9 Science

📄 GuideDraw a graph to represent a sound wave for which the density amplitude. Class 9

Draw a graph to represent a sound wave for which the density amplitude. Class 9Question 1.Draw a gra

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Class 9 Science

📄 GuideThe sound waves emitted by three sources A, B and C are represented in Fig. Class 9

The sound waves emitted by three sources A, B and C are represented in Fig. Class 9Question 1. The s

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Class 9 Science

📄 GuideGraphs representing two sound waves are given in Fig. If the scales on the X and Y axes. Class 9

Graphs representing two sound waves are given in Fig. If the scales on the X and Y axes. Class 9Ques

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Class 9 Science

📄 GuideIf 20 compressions pass a point in 4 seconds, the frequency is. Class 9

If 20 compressions pass a point in 4 seconds, the frequency is. Class 9Question 1. If 20 compression

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Class 9 Science

📄 GuideWhich observation best supports the idea that sound is a mechanical wave? Class 9

Which observation best supports the idea that sound is a mechanical wave? Class 9Revise, Reflect, Re

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Class 9 Science

📄 GuideWhat if the speed of sound in air depended on its frequency? Class 9

What if the speed of sound in air depended on its frequency? Class 9What if (Page 196)Question 1. Wh

108 views
Class 9 Science

📄 GuideAn experiment is being set up that requires echoes to arrive at least 0.2 s. Class 9

An experiment is being set up that requires echoes to arrive at least 0.2 s. Class 9Question 1. An e

93 views
Class 9 Science