Answer:
Kettlewell thought that if natural selection caused the change in the moth population, the following must be true: Heavily polluted forests will have mostly dark peppered moths. Clean forests will have mostly light peppered moths. Dark moths resting on light trees are more likely than light moths to be eaten by birds.
A pedigree is a symbolic diagram that is used to show the presence and presentation of specific alleles in the families of both parents. This is used mostly for genetically controlled diseases and conditions. If a couple is in genetic counseling a pedigree is valuable in helping to determine the risk of that couple having a child that will either present with the condition or be a carrier for the condition. A pedigree is also composed in a way, with shapes and colors, that is an easy to understand visual representation of the inheritance patterns.
Nematodes are wormlike organisms which can be seen with naked eye, live in water-filled pore spaces in the soil. Nematodes are in large number in the upper soil layers where organic matter, plant roots, and other resources are most abundant.
The functions of nematodes:
- Free-living nematodes decompose organic material into nutrients and cycled them in the soil by feeding on some bacteria and fungi.
- Nematodes help in distributing bacteria and fungi through the soil and along roots by carrying live and dormant microbes.
- They used as food for higher predators, soil microorthropodes.
- They eat disease-causing organisms, thus suppress their growth.
- They acts as potential bio- control agents.
