Answer: option A
Explanation: As demonstrated by the Hardy-Weinberg principle, the dominance or recessiveness of an allele does not determine its frequency in a population.
C. punctuated equilibrium. Scientists believe in two evolutionary theories: gradualism and punctuated equilibrium. If punctuated equilibrium suggests species can rapidly evolve into a new species, gradualism suggests that these changes (selection and variation) happen more gradually.
Answer:
Exercise
Explanation:
Cognitive impairment is the condition where a person has difficulty in recalling or remembering things. They also find it difficult to perform daily tasks and make decisions. They are not able to concentrate hence also have trouble learning new things. Cognitive impairment can be present genetically although it is observed almost in a large number of ageing people.
Exercise has been proven to help in cases of mild to severe cognitive impairment. In an experiment it was proven that 6 months of aerobic exercise reversed cognitive impairment symptoms in ageing people. It particularly benefits people carrying the APOE4 gene variant responsible for making people susceptible to Alzheimer's.
Answer:
Bluish-purple color
Explanation:
It is given that the bacterium is susceptible to penicillin family of antibiotics. Penicillin only kills gram positive bacteria. It destroys them by inhibiting the peptidoglycan cell wall synthesis. Gram negative bacteria is not affected by penicillin because it has an outer membrane covering the cell wall. The lipopolysaccharide outer membrane does not allow penicillin to reach the cell wall. Hence, the bacteria in question is gram positive.
Gram positive bacteria is stained bluish-purple on gram staining because it retains the primary dye crystal violet after washing with alcohol. Whereas gram negative bacteria loses its outer membrane on washing with alcohol and picks up the secondary dye safranin, giving red color.
Hence, color of this bacterium will be bluish-purple after using gram staining technique.