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What happens when weak ammonium hydroxide react with metal?

Posted by Rabindra Behera 9 hours ago

CBSE > Class 08 > Science

0 answers

ANSWER

What happens when yeast is added to dough

Posted by Harshit Kumar 1 day, 3 hours ago

CBSE > Class 08 > Science

1 answers

.. . 14 hours ago

As soon as these ingredients are stirred together, enzymes in the yeast and the flour cause large starch molecules to break down into simple sugars. The yeast metabolizes these simple sugars and exudes a liquid that releases carbon dioxide and ethyl alcohol into existing air bubbles in the dough.

ANSWER

Which type of vaccine is given to the new born baby

Posted by Ayush Dwivedi 1 day, 13 hours ago

CBSE > Class 08 > Science

2 answers

Rajni Maheshwari 7 hours ago

Polio is given to the baby because it effects to defeat with diseases

Rohit Kuklare 1 day, 5 hours ago

Polio

ANSWER

What is coal mine?

Posted by Komal Raskar 1 day, 17 hours ago

CBSE > Class 08 > Science

2 answers

Minakshi Vats 1 day, 5 hours ago

Chapter 1 question and answer

Nishid Gahane 1 day, 15 hours ago

Coal mine is a mine where coal is dig out from earth 🌎

ANSWER

What is living.

Posted by Divanshi Bhuriya 2 days, 9 hours ago

CBSE > Class 08 > Science

1 answers

Aafiya Naik 2 days, 7 hours ago

Living’ is something that is alive, something that can grow, move, reproduce, respire and carry out various cellular activities.

ANSWER

Give two examples of gravitational force

Posted by Akash Kumar 3 days, 10 hours ago

CBSE > Class 08 > Science

2 answers

Rajni Maheshwari 7 hours ago

Falling of an apple and falling of a metoride on earth

Disha Dhakad 2 days, 16 hours ago

Aroplane ,our body, by we are saikalling,

ANSWER

Give some use of metals and non metals

Posted by Praval Talwar 3 days, 13 hours ago

CBSE > Class 08 > Science

3 answers

Rajni Maheshwari 3 days, 10 hours ago

Nitrogen hydrogen chlorine

Khushi Rawat 3 days, 13 hours ago

Non metals are nitrogen, hydrogen , chlorine etc

Khushi Rawat 3 days, 13 hours ago

Metals are aluminium, copper, zinc etc

ANSWER

What is AIDS causing virus?

Posted by Aditi Patil 3 days, 18 hours ago

CBSE > Class 08 > Science

1 answers

Khushi Rawat 3 days, 13 hours ago

Aids is caused by the human immunodeficiency virus. You can get HIV from contact with infected blood, semen, or vaginal fluids.

ANSWER

Chapter 2 question answer biology

Posted by *Armaan Siddiqui 4 days, 4 hours ago

CBSE > Class 08 > Science

2 answers

Rajni Maheshwari 6 hours ago

Exercise Questions (1)fill in the blanks (a) Microorganisms can be seen with the help of a ____________. (b)Blue green algae fix __________ directly from air and enhance fertility of soil. (c) Alcohol is produced with the help of _____________. (d)Cholera is caused by ____________. Solutions:a-microscope b-Nitrogen c-yeast d-bacteria

Khushi Rawat 3 days, 13 hours ago

Exercise Questions 1. Fill in the blanks. (a) Microorganisms can be seen with the help of a ____________. (b) Blue green algae fix __________ directly from air and enhance fertility of soil. (c) Alcohol is produced with the help of __________. (d) Cholera is caused by __________. Soln: a) Microscope b) Nitrogen c) Yeast d) Bacteria- Vibrio cholera 2. Tick the correct answer. (a) Yeast is used in the production of (i) sugar (ii) alcohol (iii) hydrochloric acid (iv) oxygen (b) The following is an antibiotic (i) Sodium bicarbonate (ii) Streptomycin (iii) Alcohol (iv) Yeast (c) Carrier of malaria-causing protozoan is (i) female Anopheles mosquito (ii) cockroach (iii) housefly (iv) butterfly (d) The most common carrier of communicable diseases is (i) ant (ii) housefly (iii) dragonfly (iv) spider (e) The bread or idli dough rises because of (i) heat (ii) grinding (iii) growth of yeast cells (iv) kneading (f) The process of conversion of sugar into alcohol is called (i) nitrogen fixation (ii) moulding (iii) fermentation (iv) infection Soln: a) (ii) alcohol b) (ii) Streptomycin c) (i) female Anopheles mosquito d) (ii) housefly e) (iii) growth of yeast cells f) (iii) fermentation 3. Match the organisms in Column A with their action in Column B. AB(i) Bacteria(a) Fixing nitrogen(ii) Rhizobium(b) Setting of curd(iii) Lactobacillus(c) Baking of bread(iv) Yeast(d) Causing malaria(v) A protozoan(e) Causing cholera(vi) A virus(f) Causing AIDS(g) Producing antibodies Sol:- AB(i) Bacteria(e) Causing cholera(ii) Rhizobium(a) Fixing nitrogen(iii) Lactobacillus(b) Setting of curd(iv) Yeast(c) Baking of bread(v) A protozoan(d) Causing malaria(vi) A virus(f) Causing AIDS 4. Can microorganisms be seen with the naked eye? If not, how can they be seen? Soln: Microorganisms cannot be seen by the naked eye because they are very small. They can be seen by using a microscope. 5. What are the major groups of microorganisms? Soln: Major group of microorganisms are as follows Bacteria Fungi Protozoans Algae Viruses 6. Name the microorganisms which can fix atmospheric nitrogen in the soil. Soln: Rhizobium 7. Write 10 lines on the usefulness of microorganisms in our lives. Soln: Uses of microorganisms are listed below They are helpful in cleaning up of the environment. For example, the organic wastes (vegetable peels, remains of animals, faeces, etc.) are broken down into harmless and usable substances by bacteria. Curd contains several microorganisms. Of these, the bacterium, Lactobacillus promotes the formation of curd. It multiplies in milk and converts it into curd. Bacteria are also involved in the making of cheese, pickles and many other food items. Bacteria and yeast are also helpful for fermentation of rice idlis and dosa batter. Yeast reproduces rapidly and produces carbon dioxide during respiration. Bubbles of the gas fill the dough and increase its volume. This is the basis of the use of yeast in the baking industry for making breads, pastries and cakes. Microorganisms are used for the large scale production of alcohol, wine and acetic acid (vinegar). Antibiotics are being produced from bacteria and fungi. Microorganisms are helpful in producing vaccines against disease-causing agents. Some bacteria (Fig. 2.7) are able to fix nitrogen from the atmosphere to enrich the soil with nitrogen and increase its fertility. Microorganisms decompose dead organic waste of plants and animals to convert them into simple substances. These substances are again used by other plants and animals. Thus, microorganisms can be used to degrade the harmful and smelly substances and thereby clean up the environment. 8. Write a short paragraph on the harmful effects of microorganisms. Soln: Microorganisms cause diseases in plants and animals Ex; Cholera in humans is caused by bacteria called Vibrio cholera. In animals, the virus causes foot and mouth diseases. Microorganisms spoil the foods by decomposing the food material. Some microorganisms spoil leather and clothes. Microorganisms are responsible for food poisoning. 9. What are antibiotics? What precautions must be taken while taking antibiotics? Soln: Chemical agents that kill or stop the growth of disease-causing microorganisms are called antibiotics. Antibiotics should be taken only on the advice of a qualified doctor. Also, one must complete the course prescribed by the doctor.

ANSWER

In which direction does the atmospheric pressure acts in the below figure? 1 point downward upward both directions

Posted by Gbs Reddy 4 days, 16 hours ago

CBSE > Class 08 > Science

1 answers

Yuvraj Yadav 4 days, 10 hours ago

I don't the answer

ANSWER

What types of organs

Posted by Sahil Alvi 5 days, 5 hours ago

CBSE > Class 08 > Science

3 answers

Harnoor Singh Kamboj 4 days, 16 hours ago

Ch 2 microorganism all questions answer soluid

Harnoor Singh Kamboj 4 days, 16 hours ago

Microorganisms

Mannat Verma 5 days, 4 hours ago

Igtegumentary Skeletal Muscular Urinary Digestive

ANSWER

What is Irrigation method

Posted by Shreya Bagry 5 days, 5 hours ago

CBSE > Class 08 > Science

1 answers

Mannat Verma 5 days, 4 hours ago

Irrigation is the process of applying water to soil, primarily to meet the water needs of growing plants. Water from rivers, reservoirs, lakes, or aquifers is pumped or flows by gravity through pipes, canals, ditches or even natural streams. ... The three main methods of irrigation are surface, sprinkler and drip/micro.

ANSWER

What are the major grops of microorganisms?

Posted by Khanak Paliwal 6 days, 11 hours ago

CBSE > Class 08 > Science

4 answers

Pavitra Patel 4 days, 6 hours ago

Bacteria, fungi ,algae, protozoa,viruses

Abhijith Reddy 4 days, 14 hours ago

Bacteria. Fungi. Protozoa. Algae

Khushee Bhogayta 6 days, 8 hours ago

Alage Fungi Protozoa Bacteria Viruses

Logith Arun 6 days, 9 hours ago

Algae, fungi, protozoa, bacteria.

ANSWER

What is drip irrigation system?

Posted by Gideon Ganta 6 days, 11 hours ago

CBSE > Class 08 > Science

2 answers

Ayush Dwivedi 1 day, 13 hours ago

In this system, the water falls drop by drop directly near the roots.So it is called drip system

Ronak Choudhary 4 days, 15 hours ago

Dirp irrigation is the process in which water go drop by drop in the roots of the plant

ANSWER

Write different ways of storing crop production?

Posted by Aditi Katre 6 days, 13 hours ago

CBSE > Class 08 > Science

1 answers

Khushee Bhogayta 6 days, 8 hours ago

Storing in mills and silos.

ANSWER

In which season kharif crop is harvested?

Posted by Yashica Shree Shree 6 days, 17 hours ago

CBSE > Class 08 > Science

4 answers

Rajni Maheshwari 4 days, 4 hours ago

Rainy season is most suitable season for harvesting Rabi crops.During this period the crops are ready to cut and then

Pavitra Patel 4 days, 5 hours ago

In rainy season kharif crop is harvested and in the month of june to September

Khushee Bhogayta 6 days, 8 hours ago

June to October

Preetam Lamani 6 days, 16 hours ago

In rainy season kharif crop harvested

ANSWER

How the water get ice

Posted by Yash Shukla 1 week ago

CBSE > Class 08 > Science

3 answers

Khushee Bhogayta 6 days, 8 hours ago

Due to coolnrss

Pratik Rathod 1 week ago

Due to the process of freezing

Vaibhav Parmar 1 week ago

Windowing

ANSWER

For growing crops we need

Posted by Insha Momin 1 week ago

CBSE > Class 08 > Science

3 answers

Sushree Sahoo 1 week ago

For growing crop we need field seed nutrients sunlight temperature and water

Pratik Rathod 1 week ago

A good felid is neccesary

Yash Shukla 1 week ago

All thing that need to grow seed

ANSWER

What is formula of water

Posted by Rajesh Kumar 1 week, 1 day ago

CBSE > Class 08 > Science

5 answers

Sushree Sahoo 1 week ago

H2o is the formula of water

Riya Patel 1 week ago

H2o

Kavya Dixit 1 week, 1 day ago

H2O

Jeevana Dharma 1 week, 1 day ago

H2o

Rajesh Kumar 1 week, 1 day ago

H2o

ANSWER

The charge acquired by a glass rod when it is rubbed with silk is................... A)positive charge B) negative charge C)both

Posted by Anshika Aggarwal 1 week, 1 day ago

CBSE > Class 08 > Science

1 answers

Akanksha Patel 1 week ago

after rubbing, the glass rod becomes positively charged and the silk gets negative charge

ANSWER

What is Cell Meambrane

Posted by Shivam Thakkar 1 week, 2 days ago

CBSE > Class 08 > Science

2 answers

Sia 🤖 1 week, 2 days ago

The cell membrane is a biological membrane that separates the interior of all cells from the outside environment which protects the cell from its environment. The cell membrane consists of a lipid bilayer, including cholesterols that sit between phospholipids to maintain their fluidity at various temperatures.

Vani Thakur 1 week, 1 day ago

The outer covering of cell which protects it from being damaged is known as cell membrane. Cell membrane is also known as plasma membrane

ANSWER

Distinguish between metals and non - metals on the basic of yheir physical properties

Posted by Kusuma S 1 week, 2 days ago

CBSE > Class 08 > Science

1 answers

Sia 🤖 1 week, 2 days ago

Metals	Nonmetals
Metals are very hard except for sodium.	Non metals are soft except for diamonds.
Metals are generally malleable and ductile.	Non metals are generally brittle and can break down into smaller pieces.
They are shiny and lustrous.	They are not shiny and are non lustrous except iodine.
They are electropositive in nature.	They are electronegative in nature.
Metals are good conductors of heat and electricity.	Non metals are generally bad conductors of heat and electricity except graphite.
They are used in machinery. Example: Copper, silver, gold etc.	They have medicinal and chemical uses. Example: carbon, oxygen, sulphur etc.

ANSWER

Under the effect of which hormone does mammary glands develop? (A) testosterone (b)estrogens (c) thyroxine (d) adrenaline

Posted by Saniya Shaikh 1 week, 3 days ago

CBSE > Class 08 > Science

1 answers

Manisha Gundlur 1 week, 1 day ago

Growth hormone, secreted from the pituitary gland, is an important global regulator of mammary gland development, but current evidence suggests that its effect on the mammary gland is mediated largely, or even entirely, through IGF1 whose production it stimulates in the stroma

ANSWER

Which infection is caused by algae

Posted by Aasma Singla 1 week, 4 days ago

CBSE > Class 08 > Science

5 answers

Ramkanya Suthar 1 week, 3 days ago

Systemic chlorellosis,

Aasma Singla 1 week, 4 days ago

Thanks 😊😊😊

Shree Varshita Ainapur 1 week ago

kshitij mahindrakar class

Roshni Gaha 1 week, 4 days ago

Systemic chlorellosis, an emerging infection in humans caused by algae.

Aasma Singla 1 week ago

Pls tell

ANSWER

What is green house gas

Posted by Somya Giri 1 week, 5 days ago

CBSE > Class 08 > Science

2 answers

Priya Siddappa 1 week, 4 days ago

A greenhouse gas is a gas that absorbs and emits radiant energy within the thermal infrared range, causing the greenhouse effect. The primary greenhouse gases in Earth's atmosphere are water vapour, carbon dioxide, methane, nitrous oxide, and ozone.

Manan Gupta 1 week, 2 days ago

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ANSWER

What is meaning of science

Posted by Swarna Kumari 1 week, 5 days ago

CBSE > Class 08 > Science

3 answers

Sia 🤖 1 week, 5 days ago

the intellectual and practical activity encompassing the systematic study of the structure and behaviour of the physical and natural world through observation and experiment.

Yash Shukla 1 week ago

I am science

Manan Gupta 1 week, 2 days ago

This content has been hidden. One or more users have flagged this content as inappropriate. Once content is flagged, it is hidden from users and is reviewed by myCBSEguide team against our Community Guidelines. If content is found in violation, the user posting this content will be banned for 30 days from using Homework help section. Suspended users will receive error while adding question or answer. Question comments have also been disabled. Read community guidelines at https://mycbseguide.com/community-guidelines.html

Few rules to keep homework help section safe, clean and informative.

Don't post personal information, mobile numbers and other details.
Don't use this platform for chatting, social networking and making friends. This platform is meant only for asking subject specific and study related questions.
Be nice and polite and avoid rude and abusive language. Avoid inappropriate language and attention, vulgar terms and anything sexually suggestive. Avoid harassment and bullying.
Ask specific question which are clear and concise.

Remember the goal of this website is to share knowledge and learn from each other. Ask questions and help others by answering questions.

ANSWER

From the given v-t graph it can be inferred that the object is

Posted by J.G.Niveditha2007 J.G.Niveditha 1 week, 5 days ago

CBSE > Class 08 > Science

2 answers

Chandan Pilli 1 week, 5 days ago

Hi

Magesh Kanth 1 week, 5 days ago

What is royan

ANSWER

_ is the process of heat and cold treatment for preserving milk

Posted by B. Parnika B. Parnika 1 week, 6 days ago

CBSE > Class 08 > Science

3 answers

Akanksha Patel 1 week ago

The process is called pesturisation

Aasma Singla 1 week, 4 days ago

Pasteurization

Siriya Palle 1 week, 5 days ago

Pasteurization

ANSWER

_ are preserved by the use of oil and vinegar

Posted by B. Parnika B. Parnika 1 week, 6 days ago

CBSE > Class 08 > Science

2 answers

Aasma Singla 1 week, 4 days ago

Pickling

Siriya Palle 1 week, 5 days ago

Picking

ANSWER

_ are preserved by the use of oil and vinegar.

Posted by B. Parnika B. Parnika 1 week, 2 days ago

CBSE > Class 08 > Science

1 answers

Sia 🤖 1 week, 2 days ago

Use of oil and vinegar prevents spoilage of pickles because bacteria cannot live in such an environment. Vegetables, fruits, fish and meat are often preserved by this method.

ANSWER

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