Darwin's proposed mechanism for evolution is natural selection. Natural selection allows species to respond to their surroundings through time, or to become progressively excellently-suited. Natural selection is environmentally based and involves established heritable variation within a population.
They lead to changes in species over time:
- Darwin suggested species will evolve over time, new species originate from pre-existing species, and all species share a common ancestor with each other.
- In this framework each organism has its own special set of heritable i.e genetic variations from the common ancestor that have slowly developed over very longer periods of time.
- Parroted branching activities that isolate new species from a common ancestor create a multi-level tree that connects all living organisms.
<u>Answer:</u>
Mitochondria, the organelles involved in cellular respiration, can also generate chemicals called reactive oxygen species (ROSs). ROSs can damage mitochondria. Damaged mitochondria generate more ROSs than healthy mitochondria. This is an example of a positive feedback mechanism
The reactive oxygen species that are given out by the mitochondria during cellular respiration are the major cause of aging. Though this has a lot of negative effects but this also has a small amount of positive effects such as the start of angiogenesis or cell proliferation.
<u>Answer;</u>
C) organic matter; rocks.
The uppermost horizon, horizon O, in this profile is composed mostly of <u>organic matter</u>, while the lower horizon, horizon C, is composed mostly of <u>rocks.</u>
<u>Explanation;</u>
-Soil contains the following major horizons, that is A B and C. Some soils may have horizon O, which may be thin or thick or even lack in some soils. This O horizon is found at the surface of many soils and normally contains organic materials at various decomposition stages. these are materials such as plants, leaves and bugs.
-C horizon is the layer that is below the B horizon. It contains larger weathered fragments or broken up-bedrock.
<span>B. A prokaryotic cell does not have nucleus and the other one does. The most defining characteristic of eukaryotic cells is their true nucleus. Prokaryotes lack true nucleus</span> and membrane bound organelles.