Answer:
Species separated by a physical barrier for a long time, suffer allopatric speciation, so they can not interbreed anymore.
Explanation:
Allopatric speciation consists of the geographic separation of a continuous genetic background giving place to two or more new geographically isolated populations. These separations might be due to migration, extinction of geographically intermediate populations, or geological events. In this speciation, some barriers impede genetic interchange, or genetic flow, as the two new populations that are separated can not get together and mate anymore. These barriers might be geographical or ecological.
Vicariance is the geographical separation of an original population into two or more new groups. Discontinuities in the physical environment like rivers, mountains, water, etc., are physical barriers that impede genetic flow between the separated groups.
The process of allopatric speciation involves different steps:
- The emergence of the barrier.
- Interruption in the genetic interchange
- The occurrence of new mutations and their accumulation in time in each population. Slow and gradual differentiation.
- Genetic divergence by natural selection and reproductive isolation makes it impossible for the two groups to mate even if the barrier disappears.
- Prezigotic isolation mechanisms favored by selection once occurs a secondary contact between the new species in formation.
Answer:
hypha
mycelium
fruiting body
spores
Explanation:
<em>A typical fungi thallus includes many filamentous hypha that combine to form mycelium that grows underground, and produce a fruiting body reproductive structure that produce spores that disperse on the wind to new habitat.</em>
Fungi body are generally made up of hypha, a network of which forms the mycelium. The mycelium grows underground within the substrate and occasionally bring out fruiting bodies which bear the sporangium containing the spores. The spores act as agent of dispersal and are used to form new organisms when the conditions are right.
The answer is through the placenta. The placenta is formed in the uterus of the pregnant woman. Its role is in the nourishment of the fetus. The placenta provides the fetus with nutrients and removes waste. The umbilical cord connects the placenta to the fetus and it serves as the transporting passageway.
Cancer is basically a disease of uncontrolled cell division.
The first is A second is C