Unit 19       

     Materials used in Agriculture

On the basis of fulfillment of food requirements, living creatures are divided into two types:

i) Autotrophs

ii) Heterotrophs

- Autotrophs: The organisms which can synthesize their own food from carbon dioxide, water and sunlight are called autotrophs. All green plants are autotrophs.

- Heterotrophs: The organisms which cannot synthesize their own food are called heterotrophs. Human beings, animals are heterotrophs.

How do we get food?

1. Agriculture: The growing of plants or crops to obtain food is called agriculture.

2. Animal Husbandry: The branch of agriculture concerned with animals that are raised for meat, milk, fiber and other products is called animal husbandry. 

- Crops: The plants grown and cared in the field for getting food are known as crops. Eg: Grains, vegetables, fruits etc.

- Plant Nutrients: The minerals required by plants for its growth and survival are called plant nutrients. There are two types of plant nutrients:

i) Macronutrients

ii) Micronutrients

- Macronutrients: The mineral element needed by the plants in large amounts are called macronutrients. Eg: Carbon, Hydrogen, Oxygen, Nitrogen, Phosphorous, Potassium, Calcium, Magnesium, Sulphur etc.

- Micronutrients: The mineral element needed by the plants in very small amounts are called micronutrients. Eg: Manganese, Iron, Copper, Zinc, Boron, Chlorine, Molybdenum etc.

- Soil: The upper layer of the earth crust in which plants are grown is called soil.

Function of soil for the growth of plant

• It provides plant nutrients.
• It provides water through the roots.
• It provides oxygen to the roots through aeration.
• It holds or supports the plant.
• It provides humus.

Agricultural Practices

1. Preparation of Soil: Soil is prepared in three steps viz. Ploughing, levelling and manuring.
2. Sowing: Sowing is process of scattering or putting seeds in the soil for growing crop plants. It can be done either by hand or using seed drill. Also, the seedlings are transferred from nursery to main field in this process which is known as transplantation.
3. Use of Fertilizer : Organic and chemical fertilizers are used.
4. Irrigation: Irrigation is process of supplying water to crops. Water is supplied by canals, reservoir etc.
5. Control of weed: Unwanted plants from crop field are removed here.
6. Use of pesticides: They are used to control pests in crops.
7. Harvesting: Cutting and gathering of matured food crops is harvesting.
8. Threshing and Winnowing: Threshing means beating grains out of harvested crops. Winnowing is separation of grain from chaff and hey with the help of wind.
   
   
   

Fertilizer

- Fertilizers are the substances which are used to increase the fertility of soil for the good growth of plants. There are two types of fertilizer in general:

i) Organic fertilizer

ii) Chemical fertilizer

- Organic fertilizer: The fertilizer made by the action of bacteria and fungi over the animal wastes and plant buried into the soil is called organic fertilizer. Eg: Powder of mustard cake, bone meal, ash etc. Organic fertilizer are also of two types:

• Compost fertilizer: It is natural substance obtained by the decomposition of animal waste like animal dung, human wastes and plant residue, which supplies plant nutrients and humus to the soil.
  Advantages of compost fertilizer:

  1. It doesn’t change the acidity and alkalinity of soil.
  2. It consists of organic substance which helps in good growth of plant.
  3. It preserves water in the soil.
  4. It prevents erosion and leaching.
  5. It is biodegradable and doesn’t pollute the environment.

• Green fertilizer: Fertilizer obtained by decomposition of green plants in the soil of the field is called Green fertilizer. Eg: leaves of Adhatoda (asuro), Mugwort (Tite-pati), Marijuana (Ganja) etc.

- Chemical fertilizer: A salt or an organic compound containing necessary plant nutrients like nitrogen, phosphorous or potassium is called chemical fertilizer.

- Difference between Compost fertilizer and Chemical fertilizer:

Compost Fertilizer	Chemical Fertilizer
1. Compost fertilizer is prepared from decomposed organic waste.	1. Chemical fertilizer is manufactured using chemical processes.
2. It improves soil structure and fertility.	2. It increases crop yield quickly.
3. Nutrients are released slowly.	3. Nutrients are released quickly.
4. It is environment-friendly.	4. Excessive use may harm the environment.
5. It is cheaper and can be prepared at home.	5. It is costlier and must be purchased.
6. Example: Farmyard manure, vermicompost.	6. Example: Urea, DAP, NPK.

NPK Fertilizer

- NPK fertilizers are three component fertilizers providing nitogen, phosphorous and potassium. There are two types of NPK fertilizers- Compound NPK fertilizers & Blended NPK fertilizers.

🌱 Nitrogenous Fertilizers

• Urea — NH₂–CO–NH₂
• Ammonium Nitrate — (NH₄)NO₃
• Ammonium Sulfate — (NH₄)₂SO₄

🌿 Importance of Nitrogen in Plants

• Essential for the manufacture of proteins, protoplasm, and chlorophyll.
• Increases the rate of plant growth.
• Helps in storage of proteins and synthesis of large amounts of chlorophyll.

⚠️ Effects of Nitrogen Deficiency

• Plant growth stops and crop production decreases.
• Leaves turn yellow.
• Flowers do not bloom properly.
• Fruits and seeds become small.

🧬 Phosphorus Fertilizers

• Single Super Phosphate (SSP) — Ca(H₂PO₄)₂
• Triple Super Phosphate (TSP) — 3Ca(H₂PO₄)₂
• Ammonium Phosphate (DAP) — (NH₄)₃PO₄

⚡ Importance of Phosphorus in Plants

• Essential for root development and early plant growth.
• Helps in energy transfer and storage (ATP formation).
• Promotes flowering, fruiting, and seed formation.

⚠️ Effects of Phosphorus Deficiency

• Poor root growth and delayed maturity.
• Leaves may turn dark green or purplish.
• Reduced flowering and fruit formation.
• Low crop yield.

🛡️ Potassium Fertilizers

• Muriate of Potash (MOP) — KCl
• Sulfate of Potash (SOP) — K₂SO₄
• Potassium Nitrate — KNO₃

💧 Importance of Potassium in Plants

• Regulates water balance and opening–closing of stomata.
• Improves disease resistance and stress tolerance.
• Enhances quality of fruits, grains, and seeds.

⚠️ Effects of Potassium Deficiency

• Yellowing or scorching of leaf margins.
• Weak stems and lodging of plants.
• Poor fruit quality and reduced yield.
• Reduces immune power of plant.

Disadvantages of Overuse of Chemical Fertilizer

• Overuse of chemical fertilizer changes nature of soil. Either the soil becomes too acidic or too alkaline.
• Overuse of chemical fertilizer pollutes the water and make unfit for human consumption.
• Overuse of chemical fertilizer kills the aquatic animals like fish.

Pesticides

- The poisonous substance used to remove, destroy, kill or control harmful pest like rodents, insects, mites, fungi, bacteria, virus is called pesticides.

- Pesticides are of different types - Insecticides, fungicide, rodenticide, herbicide etc.

- Insecticides: The chemical compounds that are used to kill or control harmful insects are called insecticides. They are of two types: 

i) Bio-Insecticides 

ii) Chemical Insecticides

- Bio-Insecticides: The insecticides made from natural substances to kill or control insects are called bioinsecticides. Eg: Ash, Adhatoda, Neem leaves etc. 

- Chemical Insecticides: Man made chemical compounds used to kill or control harmful insects are called chemical insecticides. eg: DDT, BHC etc.

- Advantages of Bioinsecticides:

• It is pollution free.
• It has no harmful effect on human and crop.
• It is biodegradable.

- Disadvantages of Chemical insecticides:

• It pollutes water which harms aquatic organisms.
• Contact with chemical insecticide effects the nervous system and glandular system in human,
• Effects growth and reproductive capacity of birds and fishes.
• Promotes respiratory diseases.
• It not only kill harmful insects but also kill useful insect.

- Precautions while using chemical insecticides:

1. Manual for using insecticide should be studied properly. 

2. Suitable cloth, mask and gloves should be used while spraying the insecticide. 

3. Insecticide should not come in contact with eye and mouth. 

4. Insecticide should be spread in the direction of air. 

5. The equipment used to spray insecticide should be washed properly after its use. 

6. Hand should be washed properly after handling the equipment. 

- Conservation of soil quality:

1. Frequent test of quality of soil. 

2. Use of suitable farming technology like: 

    (i) Crop rotation 

    (ii) Multiple cropping 

    (iii) Maximum use of organic fertilizer 

    (iv) Minimum use of chemical fertilizer 

    (v) Suitable irrigation technology 

3. Proper use of land

Activities

1. Chemical fertilizers and pesticides used in farming have caused negative effects on human health. Write any five slogans to create awareness about this issue.

2. Farmers are confused about whether to use chemical fertilizers to increase crop production or not. What suggestions would you give to them?

 SEE 2080 Questions

1. Which of the following is netizen?

    i) Who supplies internet

    ii) who uses internet

    iii) who loves internet

    iv) who repairs internet

2. Which one is correct for A in given diagram?

    i) Modulated signal

    ii) Modulating signal

    iii) Carrier Signal

    iv) Electrical Signal

3. What are the people called who use networks or internet actively?

    i) citizens

    ii) online manager

    iii) audio video editors

    iv) Netizens

4. which one is correct for P in given diagram?

    i) Modulated signal

    ii) Modulating signal

    iii) Carrier Signal

    iv) Electrical Signal

5. What is smallest unit of computer memory?

→ The smallest unit of computer memory is bit.

6. What is purpose of using DAC in computer system?

→ The purpose of using DAC in computer system is to convert digital signal to analogue signal.

7. At which point of graph of digital signal, switch is off?

→ At point 'C'

8. For what purpose is digital signal changed into analogue signal?

→ The real world is analogue and don't understand the digital codes in 0's and 1's. Thus the digital signal is changed into analogue signal so that we people can perceive it and understand it.

9. Define Netizenship.

→ Netizenship is defined as the appropriate and responsible use of technology among internet users (netizens).

10. A late childhood stage student is using cell phone excessively since 4 years. Which type of effect of digital well being does the child have? Write any two.

→ The student will have following negative effects:

- poor eyesight

- insomnia

- lack of concentration in study etc.

11. Why is digital well being necessary? mention any two points.

→ Digital Wellbeing is necessary for following reasons:

• To reduce stress and addiction due to unnecessary use of digital technology.
• To maintain balance between online and offline life.

12. In what aspect does netizenship help your study? Mention any two points.

→ Netizenship helps our study in following ways:

• It helps us get information and study materials easily from the internet.
• It helps us communicate with teachers and classmates online for learning.

13. If you are reducing a video of 6 minutes to 4 minutes, how do you complete the task? Write any four steps to be followed.

→ In order to reduce a video of 6 minutes to 4 minutes, we should first launch the Video Editor, click on new video project and type project name after which following steps should be followed:

• Select the 6 minutes video from computer memory and drag it to the editing panel.
• Select the video and click on trim. Then play the video to chose the place where video is to be cut.
• Separate the start time and end time using two blue drag bars making clip length 4 minutes and click on done.
• Select the cut clip in the editing panel and click finish video at the end. Click on export and save the file in desired location of computer memory.

14. Write two differences between each of the following:

    i) Baseband transmission & Broadband transmission

 →

Baseband Transmission	Broadband Transmission
1. Baseband transmission uses the entire bandwidth of the medium to send a single signal.	1. Broadband transmission divides the bandwidth into multiple channels to send multiple signals.
2. Signals are transmitted in digital form.	2. Signals are transmitted in analog form.
3. Only one signal is transmitted at a time.	3. Multiple signals can be transmitted simultaneously.
4. It is commonly used in LANs such as Ethernet.	4. It is commonly used in cable TV and internet services.
5. The transmission distance is usually short.	5. The transmission distance is usually long.
6. Example: Ethernet network.	6. Example: Cable television network.

   ii) Digital communication & Analogue Communication

→

Digital Communication	Analogue Communication
1. Information is transmitted in the form of binary digits (0 and 1).	1. Information is transmitted in the form of continuous signals.
2. It is less affected by noise and interference.	2. It is more affected by noise and interference.
3. Signals can be easily stored, processed, and regenerated.	3. Signals are difficult to store and process.
4. Error detection and correction are possible.	4. Error detection and correction are difficult.
5. Quality of signal remains almost constant.	5. Signal quality decreases with distance.
6. Examples: Computer networks, mobile communication, digital TV.	6. Examples: Radio broadcasting, landline telephone, analogue TV.

 

15. Explain the concept of analogue signal with concept map and its application.

→ Analogue Signal:

Analogue signal is a signal that indicates the constantly changing physical quantity with time. It communicates the data within transmitter and receiver. This signal is highly affected from outer factors. Bandwidth is less for this transmission.

Fig: Block diagram/Concept Map 

    

Application:

- Microphone

- Vehicle Speedometer

16. Explain the transmission of digital signal and its application.

The steps involved in transmission of digital signal are as follows:

- Source: For digital communication, Source is analog signal.

- Input transducer: It converts input signal to electric signal.

- Encoder: It compresses data into minimum number of bits. It helps in easy transmission of signals. [Converts analog signal to digital.]

- Modulator: It convert digital signal into analog signal and then gives direction to pass into medium or channel.

- Channel: It is a medium which provides path for analog signal from transmitter to receiver.

- Demodulator: It demodulates the signal obtained from receiver. [converts analog to digital.]

- Decoder: It digitizes the demodulated signal so that there will be less error in output signals. [converts digital into analog.]

- Output transducer: It converts decoded signal to original physical quantity.

- Output Signal: It is the result of signal transmission process.

SEE 2081 Questions

1. Which of the following unit is used for measuring the capacity of computer memory?

    i) Hz

    ii) KHz

    iii) MHz

    iv) GB

2. Which of the following activity uses digital signal?

    i) Speaking through loudspeaker

    ii) Face to face chatting together

    iii) Chatting in internet

    iv) Watching antenna TV

3. Which one of the following is the correct relation between nibble and byte?

    i) 1 nibble = 4 byte

    ii) 2 nibble = 1 byte

    iii) 4 nibble = 1 byte

    iv) 8 nibble = 1 byte

4. Which of the following is audio file format?

    i) SVI

    ii) WAV

    iii) MOV

    iv) 3GP

5. How many bits are there in 1 byte?

    i) 2

    ii) 4

    iii) 6

    iv) 8

6. Write a precaution to be taken by good netizen.

→ Good netizen should communicate by using polite and civilized language while sending email and social media comments.

7. Write a precaution to be taken for digital well being.

→ For digital well being, one should take some time away from digital devices every once in a while.

8. Identify the transmission channel communication shown in given figure. Write any two characteristics of transmission channel shown in figure. Give one example of the use of this transmission channel.

→

9. Mention any four ways of gaining digital wellbeing.

→ We can gain digital well being in following ways: 

• By allocating time for physical and offline activities.
• By turning off notifications in public place.
• By installing digital well being application on mobile phone.
• By limiting use of Social media until certain age.

10. Write any four advantages of using digital communication in daily life.

→ Following are the advantages of using digital communication in daily life:

• We can send messages and talk to others in seconds.
• We can use mobile banking instead of cash transactions.
• We can talk to people living in other cities or countries.
• Photos, videos, and documents can be shared easily.

11. Write any two positive and two negative impacts of digital technology.

→ Positive impacts:

• Digital technology helps us learn new things easily.
• It helps us talk to people quickly.

    Negative impacts:

• Too much use can harm our eyes.
• It can make us lazy if we use it too much.

12. Write any two positive and two negative effects of using online social media.

→ Positive effects:

• Social media helps us stay in touch with friends and family.
• It helps us share ideas, photos, and information easily.

    Negative effects:

• Using social media too much can waste time.
• It can expose children to bad or unsafe content.

13. How can a short video clip be made by trimming a long video? Write in four points.

→ In order to reduce a long video to short video, we should first launch the Video Editor, click on new video project and type project name after which following steps should be followed:

• Select the long video from computer memory and drag it to the editing panel.
• Select the video and click on trim. Then play the video to chose the place where video is to be cut.
• Separate the start time and end time using two blue drag bars making desired clip length and click on done.
• Select the cut clip in the editing panel and click finish video at the end. Click on export and save the file in desired location of computer memory.

The Ultimate List of Educational Websites

The internet is the library of the 21st century. Below is a clean, categorized list of high-quality educational websites — free and paid — that will help you learn anything: courses, videos, languages, music, programming, books and more. Click any link to visit the site.

Tip: Bookmark this post and come back whenever you want to learn something new. Links open in a new tab.

Educational resources by category

Category	Sites (click to open)
Courses	Coursera Udacity edX Udemy (large catalog of paid & free courses)
Video Lessons & Lectures	Khan Academy TED Academic Earth TheNewBoston (tutorials) YouTube (educational channels: CrashCourse, MinutePhysics, CGP Grey)
Music & Theory	JustinGuitar MusicTheory.net Ultimate Guitar Teoria
Language Learning	Duolingo Memrise BBC Languages Busuu Verbling (live tutors)
Books & Audio	Project Gutenberg (free eBooks) LibriVox (free audiobooks) Bartleby
Programming & Computer Science	Codecademy Learn Code the Hard Way HTML Dog CodingBat Project Euler (math & programming)
DIY / How-to	Instructables WikiHow WonderHowTo HowStuffWorks
Documentaries & Deep Dives	Top Documentary Films Documentary Heaven
Random Knowledge & Reference	Mental Floss Snopes (fact-checking) Now I Know Sporcle (quizzes) Wikipedia
Cooking	Cooking for Engineers Reluctant Gourmet Cooklet
Lifehacks & Personal Growth	Zen Habits Lifehacker Art of Manliness
Math & Problem Solving	WolframAlpha Project Euler Math is Fun
Other Useful Sites	Etymonline (word origins) Photo.net - Learn Investopedia - University

If you want more such websites or if you have any queries, please tell us in the Comment Section!