Answer:
Genetic drift is a mechanism of evolution in which allele frequencies of a population change over generations due to chance (sampling error).
Genetic drift occurs in all populations of non-infinite size, but its effects are strongest in small populations.
Genetic drift may result in the loss of some alleles (including beneficial ones) and the fixation.
Genetic drift can have major effects when a population is sharply reduced in size by a natural disaster (bottleneck effect) or when a small group splits off from the main population to found a colony (founder effect).
Answer: elastic fibers
Explanation:
Elastic fibres are the essential durable component present in mammalian connective tissueand functions to provide proper pulmonary, cardiovascular and intestinal system structure and function. Their structural function is to provide elastic recoil and resilience for the tissues.
Elastin fibers ahve two main including microfibrils and elastin containing fibrillin play a mechanical and structural role in the arteries, and their important function is to provide the tissues with resilience and elasticity.
Hence, elastic fibers helps arteries to adapt to changes in blood pressures that accompany the heartbeat.
Answer:
Homology is a study of similar characters found in two species because of common ancestry.
Explanation:
1.Morphological homology: Species placed under same taxonomic category exhibit similar anatomical structures.
2.Ontogenetic homology: Species belongs to same taxonomic category embryological similarities
3.Molecular homology: Species show molecular similarities such as DNA,RNA and protein
An example of homology is seen in the skeletal strycture of vertebrates. That is arm of a human,leg of a cat,fin of a whale and wing of a bat.