Assertion : Chlorofluorocarbons are responsible for ozone depletion.
Reason : Ozone level decreases by as much as 67% every year.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
B.
If both assertion and reason are true but reason is not the correct explanation of assertion
A slight thinning of ozone layer occurs naturally for a few months every year over Antarctica. It decreases by 67% every year.
The primary chemicals responsible for ozone depletion are a group of chlorine containing compounds called Chloroflurocarbons (CFCs), used as coolants in air conditioners and refrigerators and propellants for aerosol cans and form blowing agents for insulation and packaging and also as solvents.
Besides halons, methyl bromide, methyl chloroform, carbon tetrachloride and nitrous oxide are also responsible for O3 loss. After their release into troposphere, CFCs and other chlorine containing compounds go to stratosphere where these are broken down by UV-radiations releasing chlorine. Similarly, Bromine (Br) is released by breakdown of halons and methyl bromide. The sunlight catalyzes the chemical reaction by which chlorine or bromine break O3 molecules and convert them into O2 molecules. This chemical reaction does not change Cl or Br and thus single chlorine or bromine atom can breakdown many thousands of O3 molecules.
Gene which suppresses other gene's activity but does not lie on the same locus is called as
epistatic
supplementary
hypostatic
codominant
Assertion : Antigen can be easily recognized because it has antigenic determinants.
Reason : The recognition ability is innate.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion : The earliest fossil form in the phylogeny of horse is eohippus.
Reason : Eohippus lived during the early pliocene epoch.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Which part of the world has a high density of organism?
Deciduous forests
Grasslands
Tropical rain forests
Savannahs
Assertion : Pollution is always caused by human activities.
Reason : Pollution is not different from contamination.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
If a homozygous red-flowered plant is crossed with a homozygous white-flowered plant, the offsprings will be
half- white flowered
half- red flowered
all white flowered
all red flowered
Assertion : Haemophilia is a recessive sex linked disease.
Reason : Haemophilia occurs due to mutation of a structural gene on chromosome 15.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Assertion : Vegetable oils are fats which are present in plant cells in soluble form.
Reason : Vegetable oils occur only in cells of embryo.
If both assertion and reason are true and reason is the correct explanation of assertion
If both assertion and reason are true but reason is not the correct explanation of assertion
If assertion is true but reason is false
If both assertion and reason are false
Pure line breed refers to
heterozygosity only
heterozygosity and linkage
homozygosity only
homozygosity and self assortment
