Variations in species help them to adapt themselves to that particular environment and give them a chance of survival. For example, thermophilic bacteria are variants that are resistant to extreme temperature. They have a chance of survival in high temperate zones while others die.
In population genetics, directional selection is a mode of natural selection in which an extreme phenotype is favored over other phenotype, causing the allele frequency to shift over time in the direction of that phenotype
Answer:
The graph shows that the population of bacteria is increasing with the passage of time. During 1st hour, the population of bacteria is 50 per ml. In second hour, the population is doubled i. e. 100 per ml. In the 3rd hour, the population reaches to 200 per ml and in 3 and half hours, the population touches the value of 300 per ml. So the graph clearly shows that population is double with each hour.
A MYSTERIOUS ailment has been devastating the much studied lions of the Serengeti National Park in Tanzania, and scientists said yesterday that it had been identified as canine distemper, a viral disease that causes severe neurological symptoms and death.
Because carbohydrates can be converted into energy but can not store energy.