Answer:
Graph A: Directional Selection
Graph B: Stabilizing Selection
Graph C: Disruptive Selection
Explanation:
Natural selection as a driving force of evolution cam be defined as a process that a population of organisms undergo in other to become adapted to an environment and survive to produce offspring that are fitter.
Thus, the following graphs represents the three types of natural selection:
Graph A: Directional Selection
Directional selection occurs when one extreme trait is favoured over others by selective pressures.
The graph shows that only one extreme trait is favoured as the population that survives seem to have majorly a particular extreme trait.
Graph B: Stabilizing Selection
In this type of natural selection, neither of the extreme traits are favoured by selective pressures. Therefore, intermediate trait become favoured over the other extreme traits.
Graph C: Disruptive Selection
Selective pressures works against the intermediate trait while both extreme trait at the spectrum are well favoured, which become more established in a population against the intermediate trait.
Answer:
The correct option is 'd': Loss of blood brain barrier.
Explanation:
Astrocytes are star shaped cells in the brain and the spinal chord and are estimated to be about 20-30% of the tissue gila.
The functions of astrocytes are as follows:
1) Maintenance of blood brain barrier.
2) Provision of nutrients to brain tissue.
3) maintain the extracellular ion balance.
4) Regulate neuronal signalling.
thus among all the options the correct answer is option B.
Answer:
many breast cancers have no obvious symptoms at all. When there are no symptoms, breast cancer can be found through a screening mammogram. The most important thing is to bring any unusual signs to your doctor's attention, and to talk to your doctor about a breast screening plan that is appropriate for you
Explanation:
Answer:
The mitotic spindle is a microtubules-based bipolar structure that segregates the chromosomes in mitosis
Answer
The ability of some fish, like clownfish, to detect predators is decreased in more acidic waters. A sudden drop in pH can as cause medical issues, such as comas and seizures in oceanic life. Fish's skeletons are also sensitive to acidity, so their development may be impacted as well.