Long Answer TypeGive reasons why:
a. Most zygotes in angiosperms divide only after certain amount of endosperm is formed.
b. Groundnut seeds are exalbuminous and castor seeds are albuminous.
c. Micropyle remains as a small pore in the seed coat of a seed.
d. Integuments of an ovule harden and the water content is highly reduced, as the seed matures.
e. Apple and cashew are not called true fruits.
Short Answer TypePlenty of algal bloom is observed in a pond in your locality.
(a) Write what has caused this bloom and how does it affect the quality of water.
(b) Suggest a preventive measure.
(a) List the three states the annuals and biennial angiosperms have to pass through during their life cycle.
(b) List and describe any two vegetative propagules in flowering plants.
Explain the role(s) of the following in biotechnology.
(a) Restriction endonuclease
(b) Gel-electrophoresis
(c) Selectable markers in pBR322
Long Answer TypePublic all over India is very much concerned about the deteriorating air quality in large parts of North India. Alarmed by this situation the Resident’s Welfare Association of your locality organised an awareness programme entitled ‘Bury not burn’. They invited you, being a biology student to participate.
(a) How would you justify your arguments that promote burying and discourage burning?
(Give two reasons)
(b) With the help of flow charts, one for each practice, depict the chain of events that follow.
(a) Following arguments can be put forward to promote burying and discourage burning:
(i) When we burn wastes, pollutants such as carbon dioxide,NO2 , SO2 , etc. are released in the atmosphere. These
pollutants damage the environment. Due to burning, smoke is released into atmosphere which causes
problems like asthma, emphysema, etc.
(ii) Burying the waste does not have any harmful effect in fact when we bury organic wastes, the soil becomes
enriched with nutrients.
(b) The solid wastes are of two types:
Biodegradable wastes These can be degraded by the microbes, e.g. organic waster paper, etc.
Non-biodegradable wastes These cannot be degraded by the microbes and can remain as such for long periods,
e.g. plastic.
Flow charts depicting effects of burying and burning are:
Short Answer TypeSecondary treatment of the sewage is also called Biological treatment. Justify this statement and explain the process
How did a citizen group called Friends of Arcata Marsh, Arcata, California, USA, help to improve water quality of the marshland using Integrated Waste Water Treatment ? Explain in four steps.
Looking at the deteriorating air quality because of air pollution in many cities of the country, the citizens are very much worried and concerned about their health. The doctors have declared a health emergency in the cities where the air quality is very severely poor.
(a) Mention any two major causes of air pollution.
(b) Write the two harmful effects of air pollution on plants and humans.
(c) As a captain of your school Eco-club, suggest any two programmes you would plan to organise in the school so as to bring awareness among the students on how to check air pollution in and around the school
Switch
