Q.4 Long Answer Questions.
1. Explain the process of sewage water
treatment before it can be discharged
into natural bodies. Why this treatment is
essential?
2. Write a note on lac culture.
3. Describe various methods of fish
preservation
4. Give an account of poultry diseases.
5. Give an account of mutation breeding
with examples.
6. Describe briefly various steps of plant
breeding methods.
( PLEASE FAST)
Answers
Answer:
1.Sewage mainly includes human excreta and contains large amounts of organic waste and pathogenic microbes. Thus it is necessary that waste should be made less polluted before discharging into water bodies. ... The sewage is then passed into the settling tank where bacteria settle and now it is known as activated sludge.
2.Lac is the scarlet resinous secretion of a number of species of lac insects, of which the most commonly cultivated is Kerria lacca. Thousands of lac insects colonize the branches of the host trees and secrete the resinous pigment. The coated branches of the host trees are cut and harvested as sticklac.
3.The fovation ur most popular methods of fish preservation are freezing, canning, smoking and pickling. Top quality fresh fish are essential for fish preservation. Of all flesh foods, fish is the most susceptible to tissue decomposition, development of rancidity and microbial spoilage.
4.These include Avian Encephalomyelitis, Avian Influenza, Avian Tuberculosis, Chicken Anaemia Virus Infection (or CAV), Chlamydiosis, Egg Drop Syndrome (or EDS), Fowl Cholera (or Pasteurellosis), Fowl Pox, Infectious Bronchitis, Infectious Bursal Disease (or Gumboro), Infectious Coryza, Infectious Laryngotracheitis.
5.Henong series soybean mutants.
Jiahezazhan and Jiafuzhan rice (mutations obtained by pollen irradiation; high yield and quality, very adaptable, resistant to plant hopper and blast)
Lumian Number 1 cotton.
Purple Orchard 3 Sweet potato.
Tiefeng 18 soybean.
Yangdao Number 6 rice.
Yangmai 156 wheat.
6.Plant breeding is the process where two genetically dissimilar varieties are purposely crossed to produce a new hybrid variety to improve the quality of food. The various steps involved in plant breeding are as follows:
(a). Collection of genetic variability: At this step, different types of genes from wild varieties are collected to maintain genetic diversity. It is also called as germplasm collection.
(b). Evaluation of germplasm and selection of parents: At this step, evaluation of the desired gene from germplasm for breeding is done.
(c). Cross-hybridization between selected parents: In this step, plants with the desirable characters are crossed to produce hybrids.
(d). Selection of superior hybrids: The progenies of the hybrids having the desired characteristics are selected through scientific evaluation.
(e). Testing, release, and commercialization of new cultivars: The selected progenies are evaluated for characters such as yield, resistance to diseases, performance, etc. by growing them in research fields. After selection and testing of seed, they are distributed to market.
Answer:
hus it is necessary that waste should be made less polluted before discharging ... The process of sewage treatment is explained in the following ... This effluent can then be released into natural water bodies. ... Type your question. ... water treatment before it can be discharged into natural water bodies. Step 1: Screening and Pumping. ...
Step 2: Grit Removal. ...
Step 3: Primary Settling. ...
Step 4: Aeration / Activated Sludge. ...
Step 5: Secondary Settling. ...
Step 6: Filtration. ...
Step 7: Disinfection. ...
Step 8: Oxygen Uptake. Primary treatment : These treatment steps involve physical removal of particles from the sewage through filtration and sedimntation. These are removed in stages; initially, floating debris is removed by sequential filtration. Then the grit are removed by sedimentation. All solids that settle form the primary sludge, and the supernatant forms the effluent. The effluent from the primary settling tank is taken for secondary treatment.
During secondary treatment, the primary effluent is passed into large aeration tanks. Air is also passed into these tanks and agitated. This enables the growth of aerobic microbes into flocs. While growing, the bacteria consume majority of the organic matter present in the effluent. This causes a significant reduction in the biochemical oxygen demand BOD of the effluent.
Essential to control pollution in natural water bodies, to check water borne diseases / pathogenic organism.
Explanation: