CBSE 12TH BIOLOGY - Online Test
Q1. When we will move away from the equator towards poles, we will find
Answer : Option C
Explaination / Solution:
When we will move away from the equator towards poles there is a gradual decrease in the species diversity. This is because climatic condition becomes gradually adverse as we move from equator to poles.
Q2. Monoecious flowers contain
Answer : Option D
Explaination / Solution:
Monoecious flowers contain both male and female reproductive parts that are androecium and gynoecium. Androecium produce male gametes and gynoecium produce female gametes.
Q3. Which of the followings are called dual gland?
Answer : Option A
Explaination / Solution:
Testis and ovary are called as dual gland as they perform two functions. They release gametes and also secretes hormone.
Q4. The alternate forms of a gene is called
Answer : Option B
Explaination / Solution:
The alternate forms of a gene are called alleles. Each trait is controlled by a pair of alleles.
Q5. Humulin is a
Answer : Option B
Explaination / Solution:
Humulin is protein that contains insulin isophane and insulin regular. It’s a manmade hormone that lowers the blood sugar level in blood.
Q6. Match the following:
Pollutant
a) nitrogen oxides
b) fluorides
c) PCBs
d) Chlorofluorocarbons
Source
i) jet aeroplane emissions
ii) coal burning
iii) lightening
iv) burning plastics
Pollutant
a) nitrogen oxides
b) fluorides
c) PCBs
d) Chlorofluorocarbons
Source
i) jet aeroplane emissions
ii) coal burning
iii) lightening
iv) burning plastics
Answer : Option B
Explaination / Solution:
Nitrogen oxides is released by lightening, fluorides from coal burning, PCBs from burning plastics and chlorofluorocarbons from jet aeroplanes emissions.
Q7. Genetic variation is created and inherited during
Answer : Option C
Explaination / Solution:
During sexual reproduction, gamete carrying different genetic combination unit together and variation in offspring is created that is inherited from generation to next generation.
Q8. The goi is able to multiply in the bacterial cell because of
Answer : Option A
Explaination / Solution:
The goi (gene of interest) is able to multiply in bacterial cell because of Ori (Origin of replication)in the plasmid of bacterial cell. Ori is a particular sequence in a genome at which replication is initiated.
Q9. Which one of the following is present today but was absent about 3.5 billion years ago?
Answer : Option B
Explaination / Solution:
Oxygen is present today in atmosphere but it was absent in atmosphere about 3.5 billion ago when origin of life begun on earth surface.
Q10. Biofortification is done to
Answer : Option D
Explaination / Solution:
Biofortification is the method to enhance the nutritional value of seeds by changing the gene of the crop that produces more protein, vitamins or other nutrient.
