Biology Chapter 5 Summary

639 Words3 Pages
Chapter 7 study guide Adaptation is a structure, behaviour and phsyclogical process that helps the organism survive and reproduce in a particular environment. Camouflage and mimicry are the examples of structural adaptation. Mimcry is a structural adaptation in which a harmless species resembles a harmful species in the coloration or structure. The changes in characteristics are the result of random, heritable mutations in genetic material that accumulate over generations. Environmental conditions determine whether a variation in an individual has a positive or negative effect, or no effect on the individual’s ability to survive and reproduce. Individuals possessing a helpful variation are more likely to survive and have higher chance of passing this variation on to their offspring. As a…show more content…
Individuals within a population may survive if they have an inherited trait that gives them a selective advantage. They can then go on to reproduce and pass on their advantage to their offspring. Agricultural crops are seletivly bred for different characteristics such as being drought-resistant or pre-resistant. However, selective breeding comes at the expense of decrease variation. Decreased variation leads to a reduced ability to respond to a changing environment. Darwin developed three kinds of theory of natural selection. Those are struggle for existence, variation and role of the environment. Survive of the fittest is the result of differences in rates of survival and reproduction. Darwin reasoned that natural selection could eventually cause isolated populations of the same species to becme separate species as they adopted to their different enviroments. Lamarck thought they stretched and stretched and stretched their necks all their lives, so their necks got longer from the effort of stretching higher and higher to reach leaves in the trees. Then their offspring would be born with longer
Open Document