What is the half life of U²³⁸, the radioactive isotope of uranium?

(1) 4500 years

(2) 4.5 million years

(3) 45 million years

(4) 4.6 billion years

The earliest known members of the horse family belong to the genus:

1. Hyracotherium                                                             

2. Equus

3. Mesohippus                                                                  

4. Merychippus

In a population of red (dominant) and white flowers, the frequency of red flowers is 91 %. What is the frequency of the red allele?

 ............... operates to eliminate intermediate phenotypes.

Many bacteria are now resistant to penicillin, because:

A change in allele frequency within a population, over a succession of generations, is called:

A plant population that reproduces by self - pollination is an extreme example of :

People who carry an allele for normal hemoglobin and an allele for sickle cell are resistant to malaria. They are examples of:

1. heteozygote advantage

2. extreme diploidy

3. outbreeding

4. recessive superiority

A deleterious allele decreases more rapidly in frequency if it is:

A population of an animal is hunted down to only 20 organisms. Later the number is restored to 10,000 organisms, but the variations in this population are highly reduced. This is called:

1. Founder Effect

2. Bottleneck effect

3. Edge effect

4. Heterosis