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Do Hydra his blood

Posted by Rbj Superstar 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Chinmay Sharma 6 years, 10 months ago

No hydra has no blood . They live and reproduce by the process of fragmentation.

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What are decomposers?

Posted by Rajeshree Pasalkar 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Sandhya Tandon 6 years, 10 months ago

Organism which decompose the Dead remain plant and animal to simple compound

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ANSWER

Suggest an experimental set up to illustrate the action of an electric fuse ?

Posted by Vansh Sinha 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

There is a maximum limit on the current which can safely flow through a circuit. If by accident the current exceeds this safe limit, the wires may become overheated and may cause fire. If a proper fuse is there in the circuit, it will blow off and break the circuit. A fuse is thus a safety device which prevents damages to electrical circuits.

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Write the function of bar screen in wastewater treatment plant ?

Posted by Nabajit Paul 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Madhav Paliwal 6 years, 10 months ago

The function of bar screen is to stop the large objects such as rags,plastic bag etc

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Write some disadvantage of deforestation?

Posted by Nabajit Paul 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Rohit Dhiman 6 years, 10 months ago

There is many disadvantage of deforestation like it can cause flood increase the temperature and soil erosion and decrease the habitats of animals.

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Suppose the two photographs, shown in Fig.13.1and Fig 13.2 . Had beeen taken at an interval of 10 sec . If adistance of 100 metreas is shown by 1 cm in these photographs ,calculate the speed of the fastest car

Posted by Karan The Great (Gryphon 6 years, 10 months ago

CBSE > Class 07 > Science

2 answers

Sapna Alageshan 5 years ago

200/10=20

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Rohit Dhiman 6 years, 10 months ago

I am so sorry the key paid write this

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Describe the steps involved in getting clarified water from wastewater?

Posted by Rohit Dhiman 6 years, 10 months ago

CBSE > Class 07 > Science

2 answers

Naitik Aggarwal 6 years, 10 months ago

1. Waste water is passed through screen bars . Large objects like rags , pastics , and napkins are separated by passing of warer through it. 2. Water is then passed thriugh grit and sand removal tank. 3. Water is then allowed to settle in a larger tank. Afrer removing the sludge from large tank , water is then passed through warer clarifier

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Harshita Singh 6 years, 10 months ago

Read page no 223 n 224 all the 4 points

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What is refraction?

Posted by Rohit Dhiman 6 years, 10 months ago

CBSE > Class 07 > Science

2 answers

Banawari Lal Yadav Yadav 6 years, 10 months ago

when the light passes through a spherical surface of the lens , it changes its path . This deviation in the path of light is called refaction of light

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Sandhya Tandon 6 years, 10 months ago

In physics refraction is the change in direction of a wave passing from one medium

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How can we take the speed from the graph give answer with a example.

Posted by Rohit Dhiman 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Meghna Thapar 5 years, 10 months ago

Distance-Time graph for uniform speed:

When an object moves with uniform speed it travels equal distances in equal intervals of time. The distance travelled is directly proportional to time. The Distance-Time graph for uniform speed is a straight line.
Distance-Time graph for Non-uniform speed: When an object moves with a non-uniform speed it travels unequal distances in equal intervals of time. In this case the distance travelled is not directly proportional to time and hence the graph is not a straight line.
Distance-Time graph when the object is stationery: The distance-time graph for an object which stops moving is a straight line parallel to the time axis. When an object becomes stationery its speed is zero.

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Calcium hydroxide reacts with nitric acid

Posted by Bread Jam 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Rohit Dhiman 6 years, 10 months ago

As the reaction between acid and base,salt and water are formed. HNO3+Ca(OH) -----Ca(NO3)2+H2O. The balance equation is :2HNO3+Ca(OH)2-----Ca(NO3)2+2H2O.

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What is xylem and phloem?

Posted by Aditya Chauhan 6 years, 10 months ago

CBSE > Class 07 > Science

2 answers

Riya Jain 6 years, 10 months ago

Xylem is a vascular tissue for the transport of water and minerals in the plant Phloem is a vascular tissue for the transport of food in the plant

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Rohit Dhiman 6 years, 10 months ago

The vascular cell which transfer water and nutrients to plants are called xylem. And the vacular cell which transfer food to the plant are called phloem.

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What is parasite and saprophyte?

Posted by Aditya Chauhan 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Yogita Ingle 6 years, 9 months ago

Parasite is the organism that lives inside the body of another organism (host) and derives the food from it. They harm the body of host. Cuscuta plant is a parasite.
Saprotroph is the organism that feeds on dead and decaying organic matter. They do not require any host. They are cleaning agents. Fungi is a saprotroph.

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What is aerator?

Posted by Rohit Dhiman 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Meghna Thapar 5 years, 11 months ago

Aerators are various mechanical devices used for aeration, or mixing air with another substance, such as soil or water. These devices are used to add oxygen to the water.

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Explain how animals dwelling in the forest help it grow and regenarate

Posted by Himen Bhuyan 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Rohit Dhiman 6 years, 10 months ago

1-animal in dispersal of seeed from one part of forest to another part, 2-Decomposer convert all the dead plants and animals into humus which is rich in nutrients and provide necessary minerals to the plant

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Explain reflection of light

Posted by Rohit Dhiman 6 years, 10 months ago

CBSE > Class 07 > Science

3 answers

Anik Kumar 6 years, 10 months ago

Reflection is the process by which light's rays change their direction when it strick on any shiny surface.

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Santosh Kumar Deo 6 years, 10 months ago

Phenomina in change in direction of in same median after stricking the surface of any object is called reflection of light

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Khushi Arora 6 years, 10 months ago

When the light falls on a shining surface(miror/natural mirrors) the light bonces back(reflects).This is called reflection.

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Dispersal of seeds

Posted by Sh ~?Shrawni 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Yogita Ingle 6 years, 10 months ago

Seeds of a plant get dispersed to different places and form different plants at different places.
Seeds are dispersed by water, wind and animals.
Wind blow off the winged seeds of drumsticks, light seeds of grasses, hairy seeds of oak and hairy fruit of sunflower.

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A convex lens is said to have a real focus and a concave lens a Virtual Focus .why?

Posted by Saloni Dholpuriya 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Yogita Ingle 6 years, 10 months ago

In a convex lens, the parallel rays of light passing through the lens actually meet at the focus in front of the lens. This is why it is called real focus. But in a concave lens, the rays of light passing through the lens diverge and when these diverging rays are produced backward, they appear to meet at a point behind the lens. This point is the focus of the lens. Because the light rays do not actually meet at the focus, it is called virtual or imaginary focus.

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What is the difference between water table, groundwater and aquifer?

Posted by Anik Kumar 6 years, 10 months ago

CBSE > Class 07 > Science

2 answers

R A 6 years, 10 months ago

The upper layer of water is known as water table. Water which seeps under the ground is known as groun water

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Sarthak Halder 6 years, 10 months ago

Water table and groundwater are same but the aquifer is different from them. We can take water from water table but we can't take water from aquifer. The water of aquifer is more clean and pure than the water of water table

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What is a range of clinical thermometer in celsius and fahrenheit

Posted by Kaashvi Jain 6 years, 10 months ago

CBSE > Class 07 > Science

2 answers

Sarthak Halder 6 years, 10 months ago

94to108 degree farhenheit

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Sarthak Halder 6 years, 10 months ago

35to45 degree celsius

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Explain why there is a need of variety of animals and plants in a forest

Posted by Prem Kishor 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Gaurav Seth 6 years, 10 months ago

A greater variety of plants and animals in the forests helps it to regenerate and grow. Greater variety of plants means more food and habitat for the herbivores. An increase in herbivores means more food for carnivores. Decomposers help to maintain the supply of nutrients to the soil and to the growing plants.

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Write 4 major part of forest

Posted by Sandhya Tandon 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Meghna Thapar 5 years, 11 months ago

Forests are an important renewable natural resource. They are useful in the following ways:

Plants purify air by utilizing carbon dioxide in the atmosphere. They also maintain a balance between oxygen and carbon dioxide and prevent global warming on earth.
They provide food to wild animals directly or indirectly. Herbivores eat plants and carnivores prey upon herbivores.
They provide useful materials like firewood, timber, bamboo, wood for paper, gum, resin, fibre, honey, bee wax, bidi leaf, etc. They also provide spices like black pepper, cardamom, cinchona, cinnamon, etc.
Plants are a source of many medicines. Ayurvedic medicines are prepared from medicinal plants like tulsi, neem, jamun, turmeric, ginger, etc.

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Which component of food changes into amino acids after digestion??

Posted by Ananya Pandey 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Niyati Niyati 6 years, 10 months ago

Protein

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When the amount of water is 2.5 and the time is 4 hours and the percolation rate is 10.4 guess the type of soil

Posted by Shravan Mehndiratta 6 years, 10 months ago

CBSE > Class 07 > Science

0 answers

ANSWER

What is nitric acid

Posted by Shivam Yadav Yadav 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Sarthak Halder 6 years, 10 months ago

Nitric acid is the most dangerous acid in the world, where it drops it makes a hole there

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ANSWER

Explain concave and convex lens

Posted by Raviraj Ghatage 6 years, 10 months ago

CBSE > Class 07 > Science

1 answers

Yogita Ingle 6 years, 10 months ago

A convex lens or converging lens focuses the light rays to a specific point whereas a concave lens or diverging lens diverges the light rays. A concave lens is thinner in the middle and thicker at the edges. A convex lens is thicker in the middle and thinner at the edges.

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Equatation of photosynthesis

Posted by Raviraj Ghatage 6 years, 10 months ago

CBSE > Class 07 > Science