Question
Microbes can be used to decrease the use of chemical fertilizers and pesticides. Explain how this can be accomplished.###How biofertilizers increase fertility of soil?
✓
Answer
→ Due to our present day life styles, environmental pollution is a major cause of concern.
→ The use of chemical fertilizers to meet the ever-increasing demand of agricultural produce has contributed significantly to this pollution.
→ There are problems associated with the overuse of chemical fertilizers and there is a large pressure to switch to organic farming the use of biofertilizers.
→ Biofertilizers are organisms that enrich the nutrient quality of the soil.
→ The main sources of biofertilizers are bacteria, fungi and cyanobacteria.
→ The nodules on the roots of leguminous plants are formed by the symbiotic association of Rhizobium.
→ These bacteria fix atmospheric nitrogen into organic forms, which is used by the plant as nutrient.
→ Other bacteria can fix atmospheric nitrogen while free-living in the soil Azospirillum and Azotobacter, enriching the nitrogen content of the soil.
→ Fungi are also known to form symbiotic associations with plants(mycorrhiza).
→ Many members of the genus Glomus form mycorrhiza.
→ The fungal symbiont in these associations absorbs phosphorus from soil and passes it to the plant.
→ In paddy fields, cyanobacteria serve as an important biofertilizer.
→ Currently, in our country, a number of biofertilizers are available commercially in the market and farmers use these regularly in their fields to replenish soil nutrients and to reduce dependence on chemical fertilizers.
→ In agriculture, there is a method of controlling pests that relies on natural predation rather than introduced chemicals.
→ The use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides.
→ A biological control being developed for use in the treatment of plant disease is the fungus Trichoderma. Trichoderma species are free-living fungi.
→ Trichoderma is a biocontrol agent of several plant pathogens.
→ The use of chemical fertilizers to meet the ever-increasing demand of agricultural produce has contributed significantly to this pollution.
→ There are problems associated with the overuse of chemical fertilizers and there is a large pressure to switch to organic farming the use of biofertilizers.
→ Biofertilizers are organisms that enrich the nutrient quality of the soil.
→ The main sources of biofertilizers are bacteria, fungi and cyanobacteria.
→ The nodules on the roots of leguminous plants are formed by the symbiotic association of Rhizobium.
→ These bacteria fix atmospheric nitrogen into organic forms, which is used by the plant as nutrient.
→ Other bacteria can fix atmospheric nitrogen while free-living in the soil Azospirillum and Azotobacter, enriching the nitrogen content of the soil.
→ Fungi are also known to form symbiotic associations with plants(mycorrhiza).
→ Many members of the genus Glomus form mycorrhiza.
→ The fungal symbiont in these associations absorbs phosphorus from soil and passes it to the plant.
→ In paddy fields, cyanobacteria serve as an important biofertilizer.
→ Currently, in our country, a number of biofertilizers are available commercially in the market and farmers use these regularly in their fields to replenish soil nutrients and to reduce dependence on chemical fertilizers.
→ In agriculture, there is a method of controlling pests that relies on natural predation rather than introduced chemicals.
→ The use of biocontrol measures will greatly reduce our dependence on toxic chemicals and pesticides.
→ A biological control being developed for use in the treatment of plant disease is the fungus Trichoderma. Trichoderma species are free-living fungi.
→ Trichoderma is a biocontrol agent of several plant pathogens.
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Read the following and answer any four questions from (i) to (v) given below:
The anther is a four-sided structure consisting of four microsporangia located at the corners, two in each lobe. TI1e microsporangia develop further and become pollen sacs. In a transverse section, a typical microsporangium appears near circular in outline. It is generally surrounded by four wall layers-the epidermis, endothecium, middle layers and the tapetum.
The anther is a four-sided structure consisting of four microsporangia located at the corners, two in each lobe. TI1e microsporangia develop further and become pollen sacs. In a transverse section, a typical microsporangium appears near circular in outline. It is generally surrounded by four wall layers-the epidermis, endothecium, middle layers and the tapetum.
- A dithecous another consists of (A) microsporangia, (B) in each lobe.
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S. No
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A
|
B
|
|
(a)
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Four
|
Two
|
|
(b)
|
Two
|
One
|
|
(c)
|
Two
|
Two
|
|
(d)
|
Four
|
One
|
- The given diagram shows microsporangium of a mature anther. Identify A, B and C.
|
(a)
|
A-Middle layer
|
B-Endothecium
|
C-Tapetum
|
|
(b)
|
A-Endothecium
|
B-Tapetum
|
C- Middle layer
|
|
(c)
|
A-Endothecium
|
B-Middle layer
|
C-Tapetum
|
|
(d)
|
A-Tapetum
|
B-Middle layer
|
C-Endothecium
|
- The function of labelled part X is:
- Dehiscence.
- Mechanical.
- Nutrition.
- Protection.
- Select the incorrect statement.
- Microsporangium is generally surrounded by four wall layers-epidermis, endothecium, middle layers and tapetum.
- Outer three layers perform functions of protection and dehiscence of anthers.
- Cells of tapetum possess dense cytoplasm and generally have more than one nucleus.
- Cells of tapetum undergo meiosis and produce microspore tetrads.
- Which function oftapetum is correct?
- Helps in pollen wall formation.
- Transportation of nutrients to inner side of another.
- Synthesis of callase enzyme for separation of microspore tetrads.
- All of these.
Read the following and answer any four questions from (i) to (v) given below:
Enzymes are best known for their ability to catalise biochemical reactions without undergoing any change. A large number of enzymes are being used in biotechnological industry. Most of them are obtained from microbes. Proteases degrade proteins and polypeptides. Most of the commercially applicable proteases are alkaline and are biosynthesised mainly by bacteria such as Pseudomonas, Bacillus and some fungi like, Aspergillus. These enzymes are used in clearing beer, softening of bread and meat, degumming of silk, etc. Alkaline serine proteases have the largest applications in bio-industry. Alkaline proteases have shown their capability to work under high pH, temperature and in presence of inhibitory compounds. Another important group of enzymes is amylases. Amylolytic enzymes act on starch. These are obtained from Aspergillus, Rhizopus and Bacillus sp. These are used in softening and sweetening of bread, production of alcoholic beverages from starchy materials, clearing of turbidity in juices caused by starch, etc.
Enzymes are best known for their ability to catalise biochemical reactions without undergoing any change. A large number of enzymes are being used in biotechnological industry. Most of them are obtained from microbes. Proteases degrade proteins and polypeptides. Most of the commercially applicable proteases are alkaline and are biosynthesised mainly by bacteria such as Pseudomonas, Bacillus and some fungi like, Aspergillus. These enzymes are used in clearing beer, softening of bread and meat, degumming of silk, etc. Alkaline serine proteases have the largest applications in bio-industry. Alkaline proteases have shown their capability to work under high pH, temperature and in presence of inhibitory compounds. Another important group of enzymes is amylases. Amylolytic enzymes act on starch. These are obtained from Aspergillus, Rhizopus and Bacillus sp. These are used in softening and sweetening of bread, production of alcoholic beverages from starchy materials, clearing of turbidity in juices caused by starch, etc.
- Polypeptides are degraded by:
- Amylases.
- Proteases.
- Pectinases.
- Lipases.
- Amylolytic enzymes are not obtained from:
- Aspergillus.
- Aspergillus.
- Mucor.
- Bacillus.
- Clearing of turbidity in juices caused by starch is achieved by:
- Amylases.
- Proteases.
- Rennet.
- Both (a) and (b).
- Select the incorrect option from the following.
- Enzymes are proteinaceous substances.
- Enzymes are substrate specific.
- Enzymes are large sized molecules.
- Microbial enzymes can work only in normal temperature and pH.
- A farmer harvests corns and prepares corn starch. He wants to prepare some corn syrup from this. for the conversion he needs to use enzyme ______.
- Amylase.
- Glucoamylases.
- Glucoisomerases.
- All of these.
Read the following text carefully and answer the questions that follow:
When a microorganism invades a host, a definite sequence of events usually occur leading to infection and disease, causing suffering to the host. This process is called pathogenesis. Once a microorganism overcomes the defense system of the host, development of the disease follows a certain sequence of events as shown in the graph. Study the graph given below for the sequence of events leading to appearance of a disease and answer the questions that follow:
i. In which period, according to the graph there are maximum chances of a person transmitting a disease/infection and why? (1)
ii. Study the graph and write what is an incubation period. Name a sexually transmitted disease that can be easily transmitted during this period. Name the specific type of lymphocytes that are attacked by the pathogen of this disease. (1)
iii. Draw a schematic labelled diagram of an antibody. (2)
OR
In which period, the number of immune cells forming antibodies will be the highest in a person suffering from pneumonia?
Name the immune cells that produce antibodies. (2)
When a microorganism invades a host, a definite sequence of events usually occur leading to infection and disease, causing suffering to the host. This process is called pathogenesis. Once a microorganism overcomes the defense system of the host, development of the disease follows a certain sequence of events as shown in the graph. Study the graph given below for the sequence of events leading to appearance of a disease and answer the questions that follow:
i. In which period, according to the graph there are maximum chances of a person transmitting a disease/infection and why? (1)
ii. Study the graph and write what is an incubation period. Name a sexually transmitted disease that can be easily transmitted during this period. Name the specific type of lymphocytes that are attacked by the pathogen of this disease. (1)
iii. Draw a schematic labelled diagram of an antibody. (2)
OR
In which period, the number of immune cells forming antibodies will be the highest in a person suffering from pneumonia?
Name the immune cells that produce antibodies. (2)
Explain Species-Area relationships graph.
For food related services, granting patent for transgenic organisms is becoming complicated. Explain with example.
How interesingly Gene is amplified by using PCR? Explain with diagram.
Describe tissue culture.
Read the following text carefully and answer the questions that follow:
When a microorganism invades a host, a definite sequence of events usually occur leading to infection and disease, causing suffering to the host. This process is called pathogenesis. Once a microorganism overcomes the defense system of the host, development of the disease follows a certain sequence of events as shown in the graph. Study the graph given below for the sequence of events leading to appearance of a disease and answer the questions that follow:
i. In which period, according to the graph there are maximum chances of a person transmitting a disease/infection and why? (1)
ii. Study the graph and write what is an incubation period. Name a sexually transmitted disease that can be easily transmitted during this period. Name the specific type of lymphocytes that are attacked by the pathogen of this disease. (1)
iii. Draw a schematic labelled diagram of an antibody. (2)
OR
In which period, the number of immune cells forming antibodies will be the highest in a person suffering from pneumonia?
Name the immune cells that produce antibodies. (2)
When a microorganism invades a host, a definite sequence of events usually occur leading to infection and disease, causing suffering to the host. This process is called pathogenesis. Once a microorganism overcomes the defense system of the host, development of the disease follows a certain sequence of events as shown in the graph. Study the graph given below for the sequence of events leading to appearance of a disease and answer the questions that follow:
i. In which period, according to the graph there are maximum chances of a person transmitting a disease/infection and why? (1)
ii. Study the graph and write what is an incubation period. Name a sexually transmitted disease that can be easily transmitted during this period. Name the specific type of lymphocytes that are attacked by the pathogen of this disease. (1)
iii. Draw a schematic labelled diagram of an antibody. (2)
OR
In which period, the number of immune cells forming antibodies will be the highest in a person suffering from pneumonia?
Name the immune cells that produce antibodies. (2)
Read the following and answer any four questions from (i) to (v) given below:
Age sex structure of a population can be depicted in the form of a pyramid by plotting the percentage of population of each sex in each age class. Two age sex pyramids are as follows.
Age sex structure of a population can be depicted in the form of a pyramid by plotting the percentage of population of each sex in each age class. Two age sex pyramids are as follows.
- Which of the following is correct regarding pyramid B?
- It represents stable population.
- It represents expanding population.
- It represents declining population.
- Both (a) and (b).
- Total number of individuals of a species per unit area per unit time is called.
- Population size.
- Population density.
- Demography.
- Population dynamics.
- Which of the following is correct regarding age sex pyramid A and B?
- A represents the age sex pyramid of developed country.
- B represents the age sex pyramid of developing country.
- A represents rapidly growing population.
- Both (a) and (b).
- A population with a large proportion of older individuals than younger ones will likely to:
- Grow larger first and then decline.
- Continue to grow indefinitely.
- Decline.
- None of these.
- Assertion: Bell shaped age pyramid represents a stable population.
- Both assertion and reason are true and reason is the correct explanation of assertion.
- Both assertion and reason are true but reason is not the correct explanation of assertion.
- Assertion is true but reason is false.
- Both assertion and reason are false.
Read the following and answer any four questions from (i) to (v) given below:
Priya was 4 years old when she contracted chicken pox. It took her around 15 days to recover completely. Now Priya is 5 years old, so her mother got her vaccinated few days back for DPT ($5^{th}$ dose) as per immunisation program. Recently she was playing with her friend in the park when her friend accidently fell on iron pipe and badly bruised her knee. She was taken to the hospital where doctor gave her ATS injection and painkillers. Based on the above information, answer the following questions.
→Priya was 4 years old when she contracted chicken pox. It took her around 15 days to recover completely. Now Priya is 5 years old, so her mother got her vaccinated few days back for DPT ($5^{th}$ dose) as per immunisation program. Recently she was playing with her friend in the park when her friend accidently fell on iron pipe and badly bruised her knee. She was taken to the hospital where doctor gave her ATS injection and painkillers. Based on the above information, answer the following questions.
- Select the correct statement.
- Priya has developed natural active immunity against chicken pox.
- Priya has developed artificial active immunity against DPT.
- Priya's friend has developed artificial passive immunity against tetanus.
- All of these
- Which of the following do you think is an example of natural passive immunity?
- Administration of AGS (anti gas gangrene serum) in a person.
- Transfer of IgA antibodies from mother to baby through mother's milk.
- A person recovered from viral infection.
- A child vaccinated for polio.
- Which of the following is true for active immunity?
- It provides immediate relief.
- It is temporary, not long lasting
- It has no side effects.
- None of these
- Select the incorrect match.
- Passive immunity-IgG antibodies crossing placental barrier to reach fetus.
- Active immunity-Vaccination against corona virus.
- Active immunity-Administration of antidiphtheria serum in patient.
- Passive immunity-Fetus having mother's milk.
- Assertion: A person recovered from measles develops an active immunity against this infection.
- Both assertion and reason are true and reason is the correct explanation of assertion.
- Both assertion and reason are true, but reason is not the correct explanation of assertion.
- Assertion is true, but reason is false.
- Both assertion and reason are false.