Home | | Science 9th std | Answer the following questions

Economic Biology | Biology | Science - Answer the following questions | 9th Science : Biology : Economic Biology

Chapter: 9th Science : Biology : Economic Biology

Answer the following questions

Science : Biology : Economic Biology : Book Back Important Questions, Answers, Solutions : Answer briefly, Answer in detail, Exercise Numerical Problems, Intext Activities




IV. Differentiate the following :


(a) Exotic breed and Indigenoos breed.


Exotic Breed

1. The exotic breeds are imported from foreign countries.

2. They include Jersey, Brown Swiss, Holstein - Friesian.

Indigenous Breed

1. Indigenous Breeds are native of India.

2. They include Sahiwal, Red Sindhi, Deoni and Gir.


(b) Pollen and Nectar



It is fine powder of microscopic particles from the male flower.

Pollen is produced by anther, male reproductive organ.


It is a sweet substance, produced by plants to attract pollinators such as bee, butterfly.

Nectar is converted into Honey.


(c) Shrimp and Prawn



Marine inhibited prawns are called Shrimps, which breed in deep sea.


Prawn are crustaceans inhibited in fresh water, marine water, estuaries, etc


(d) Farmyard manure and Sheep manure


Farmyard manure

• It is a mixture of cattle dung, urine, litter material, and other dairy wastes.

• 0.5% Nitrogen, 0.2% Phosphate, 0.5% potash.

• Less compared to sheep manure

Sheep manure

• This is the manure of sheep or Goat

• 3% Nitrogen, 1% phosphorus pentoxide 2% potassium oxide.

• High nutrients.


VI. Answer briefly:


1. What are secondary metabolites?

Answer: Secondary metabolites are organic compounds produced by bacteria, fungi, (or) plants which are not directly involved in the normal growth, development or reproduction of the organism.


2. What are the types of vegetable garden?

Answer: Types of vegetable gardens are

(1) Kitchen or Nutrition gardening

(2) Commercial gardening

(3) Vegetable forcing

(4) Green house (or) Poly House

(5) Organic Vegetable Gardening.


3. Mention any two mushroom preservation methods.

Answer: We can preserve mushrooms in any of the following methods:

(i) Freezing

(ii) Drying

(iii) Canning

(iv) Vacuum Cooling

(v) Gamma radiation and storing at 15°C.


4. Enumerate the advantages of vermicompost over chemical fertiliser.

Answer: (1) Vermicompost is free from pathogens and toxic elements.

(2) It enhances decomposition of organic matter in soil.

(3) It is rich in beneficial microflora.

(4) It contains valuable vitamins, enzymes and growth regulator substances.


5. What are the species of earthworm used for vermiculture?

Answer: Earthworms for vermicompost:

(1) Indian blueworm (Perionyx excavatus)

(2) Red worms (Eisenia fetida)

(3) African night crawler (Eudrilus eugeniae)


6. List the medicinal importance of honey.

Answer: (l) Honey has an antiseptic and antibacterial property.

(2) It is blood purifier.

(3) It helps in building up of haemoglobin content in the blood.

(4) It prevents cough, cold, fever and relieves sore throat.

(5) It is a remedy for ulcers of tongue, stomach and intestine.

(6) It enhances digestion and appetite.


VII.Answer in detail:


1. Enumerate the advantage of hydroponics.

Answer: Hydroponics is the method of growing plants without soil, using mineral nutrient solutions in water.

 The Advantages of Hydroponics:

(1) Conservation of water and nutrients.

(2) Controlled plant growth.

(3) In deserts and Arctic regions, hydroponics can be an effective alternative method.


2. Define Mushroom culture. Explain the mushroom cultivation methods.

Answer: Mushroom cultivation: It is a technology of growing mushrooms using plant, animal and Industrial waste.

Major stages of Mushroom cultivation:

(1) Composting:


(1) Mix paddy straw with cow dung and inorganic fertilizers.

(2) Keep at 50°C for one week.

(2) Spawning: Spawn is mushroom seed

Preparation: Growing fungal mycelium in graisn under sterile conditions. Spawn is sown on compost.

(3) Casing:

Compost is covered with thin layer of soil to support the growth of mushroom through humidity and helps temperature regulation.

(4) Pinning:

(1) Mycelium starts to form little buds (pins)

(2) These little white buds develop into mushroom.

(5) Harvesting:

(1) Temperature: 15°C - 23°C.

(2) Mushroom grow 3cm in a week.

(3) After 3 weeks, they can be harvested.


3. What are the sources of organic resources for vermicomposting?

Answer: Biologically degradable organic wastes are used as potential organic resources for vermicomposting.

They are:

(1) Agricultural wastes (Crop residue, Vegetables waste, Sugarcane trash).

(2) Crop residues (rice straw, tea wastes, cereal and pulse residues, rice husk, tobacco wastes, coir wastes).

(3) Leaf litter.

(4) Fruit and vegetable wastes.

(5) Animal wastes (cattle dung, poultry droppings, pig slurry, goat and sheep droppings).

(6) Biogas slurry.


4. Give an account of different types of fish ponds used for rearing fishes.

Answer: Different types of Ponds

(1) Breeding ponds:

Healthy and sexually mature male and female fishes are collected and introduced in the pond for breeding.

(2) Hatchling ponds:

The fertilized eggs are transferred from breeding ponds to hatchling pits for hatching.

Two types of pits: (1) Hatcheries (2) Hatching hapas.

(3) Nursery ponds:

(1) Hatchings are transferred from hatching pits after 2 to 7days.

(2) The hatchings grow into fry and are cultured for about 60 days with proper feeding till they reach 2 - 2.5cm in length.

(4) Rearing ponds:

The fish fry are transferred from nursery pond to rearing ponds and are maintained for about three months till they reach 10 to 15 cm in length.

(5) Stocking pond (or Culture pond or Production pond)

These ponds are used to rear fingerlings upto marketable size.

Pond is manured with organic manure and inorganic fertilizers.


5. Classify the different breeds of the cattle with suitable examples.



VIII. Higher Order Thinking Skills:


l. Biomanuring plays an important role in agriculture. Justify.

Answer: (1) Biomanuring reduces soil pollution, water pollution and air pollution, etc.

(2) It protects soil health and promotes soil fertility. 

(3) It provides healthy production of vegetables, fruits etc.

(4) It makes the soil fertile by adding nutrients like nitrogen.


2. Each bee hive consists of hexagonal cells. Name the material in which the cell is formed and mention the significance of the hexagonal cells.

Answer: (1) The comb of the bees is formed mainly by the secretion of the wax glands present in the abdomen of the worker bee.

(2) A comb is a vertical sheet of wax with double layer of hexagonal / cells.

(3) Hexagonal cells serve as storage vessels for honey as well as homes to raise the young bees.


Tags : Economic Biology | Biology | Science , 9th Science : Biology : Economic Biology
Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail
9th Science : Biology : Economic Biology : Answer the following questions | Economic Biology | Biology | Science

Privacy Policy, Terms and Conditions, DMCA Policy and Compliant

Copyright © 2018-2023 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.