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The collection of lac from the host plant is known as harvesting. Harvesting may be done before swarming (immature) or after swarming (mature). Immature harvesting produces ‘Ari lac’ whereas mature harvesting produces the mature lac. Lac cut from the host plant is called ‘Stick lac’.

The lac present on the twig is scraped and collected. After grinding, the unnecessary materials like dusts and fine particles are removed. The resultant lac is called ‘seed lac’. The seed lac is sun dried and then melted to produce ‘shellac’.

The correct answer is B) 30 – 35 days.

1. c) Silkmoth

2. c) Larva

3. c) Removing wool with a thin outer layer of skin

4. d) Mulberry tree

5. c) Mulberry

Culturing of animals in the water salinity ranges from 36 – 40% is called Metahaline culture. Eg, Brine shrimp (Artemia salina).

(a) Deep water culture

Artemia is commonly known as the brine shrimp.

Artemia is commonly known as the brine shrimp. It is a crustacean and lives in high saline waters because of its high osmoregulatory capacity.

Cultivable fishes like tilapia, trout, koi, gold fish, bass etc., are cultured in aquaponics. Common cultivable plants like tomato, pepper, lettuce, cucumber, and rose are co-cultivated in this method.

(a) Indigenous fresh water

Droppings of poultry can be used as in Manure fields.

1. When the eggs are hatched the larvae come out, these are kept in chandrikalu. 

2. Chandrikalu are specialized cane structures where mulberry leaves are also kept for larval feeding. 

3. This larva forms the cocoon. These are used for obtaining silk fibres. 

4. After 2 – 3 days cocoons formation, farmers remove them from chandrikalu and treat them under steam for 10 to 15 minutes. 

5. The process of killing larvae inside the cocoon by putting them in steam is called stifling.

Importance of stifling:

The larvae in the cocoons have to be killed by stifling otherwise larvae inside cocoons will come out by breaking open the cocoons.

1. Hence, we can not derive continuous thread of silk This will reduce the quality of silk fibre. 

2. Stiffled cocoons can be stored for a long time and can be sold in market.

Characteristics of cultivable fishes. The special characteristic features of cultivable fishes are:

1. Fishes should have high growth rate in short period of culture. 

2. They should accept supplementary diet. ‘ 

3. They should be hardy enough to resist some common diseases and infection of parasites.

4. Fishes proposed for poly culture should be able to live together without interfering or attacking other fishes. 

5. They should have high conversion efficiency so that they can effectively utilize the food.

pH of the freshwater should be around neutral and salinity below 5ppt.

1. Cultivation of food plants for the silkworms, 

2. Rearing of silkworms, and

3. Reeling and spinning of silk.

The first two are agricultural and the last one is an industrial component. Only felt species of silkworms are used in the sericulture industry.

(b) A combination of aquaculture and hydroponics

Aquaculture is a branch of science that deals with the farming of aquatic organisms such as fish, molluscs, crustaceans and aquatic plants.

During the breeding season in winter, a unique flight taken by the queen bee followed by , several drones is called nuptial flight.

Prawn is rich in Glycogen protein with low fat content.

Culturing of animals in the salinity ranges from 36- 40% is called Metahaline culture.

(c) Brackish water aquaculture

The droppings of poultry are rich in nitrogen, potash and Phosphates.

(b) Mariculture

Types of cultivable fish: 

Cultivable fish are of 3 types:- 

1. Indigenous or native fresh water fishes (Major carps, Catla, Labeo, Clarias).

2. Salt water fishes acclimatized for fresh water (Chanos, Mullet). 

3. Exotic fishes are imported from other counties (Common carps).

The process of killing the cocoons is called stifling.

(c) Assertion and reason is correct but related

On the basis of source, aquaculture can be classified into three categories. 

They are 

1. Freshwater aquaculture 

2. Brackish water aquaculture 

3. Marine water aquaculture.

Correct Answer is: (b) Stifling

The flesh of prawn is palatable and rich in glycogen, protein with low fat content.

Economic zoology is a branch of Science that deals with economically useful animals. It involves the study of application of animals for human welfare.

Major carps have proved to be best suited for culture in India, because the carps 

1. Feed on zooplanktons and phytoplanktons, decaying weeds, debris and other aquatic plants. 

2. They can survive in turbid water with slightly higher temperature. 

3. Can tolerate O variations in water. 

4. Can be transported from one place to other easily. 

5. They are highly nutritive and palatable

On the basis of the moults they undergo in the larval stage, B. mori is divided into three races. 

They are:

1. Tri moulters – 3 moults 

2. Tetra moulters – 4 moults 

3. Penta moulters – 5 moults

• On the basis of voltinism (the number of broods raised per year), three kinds of races are recognised. They are:
• Univoltines – one brood only
• Bivoltines – two broods only
• Multivoltines – more than two broods

Grasserie is the viral disease of Bombyx mori caused by BmNPV.

Victory 1, S3 6, G2 and G4

June, July, November and December

Correct Answer is: (d) Eri

(c) Attacus ricini

1. Animals for food and food products 

2. Economically beneficial animals

3. Animals of aesthetic importance 

4. Animals for scientific research

Fish oil is derived from the Liver of fish.

External factors affecting fish culture. The factors that affect fish culture are temperature, light rain, water, flood, water current, turbidity of water, pH hardness, salinity and dissolved O₂ . Light and temperature also play an important role in fish breeding.

Bombyx mori produces large amount of silk in India and Antheraea assamensis produces least amount of silk in India.

Correct Answer is: (c) 3 – c – III

Applications of earthworm in technology of composting and bioremediation of soils and other activities is called Vermitech.

Vermiculture is the process of using earthworms to decompose organic food waste, into a nutrientrich material capable of supplying necessary nutrients which helps to sustain plant growth.

Fish is more efficient in converting a greater proportion of feed they receive into flesh because as fish live in water they expend less energy to maintain internal body temperature and also by excreting a more simple form of urine (ammonia).

Correct Answer is: (c) Eudrillus

(a) Eudrilus eugeniae

Earthworms play a vital role in maintaining soil fertility. Hence, they are called as ‘friends of farmers’.

(c) They make the soil porous

(d) Synthesis of organic substances