Answer:
Each time a cell prepares to divide into 2 new cells, it must make a new copy of the DNA in its chromosomes. This process is not perfect, and errors can occur that may affect genes within the DNA. Cancers can be caused by DNA mutations (changes) that turn on oncogenes or turn off tumor suppressor genes.
Explanation:
Answer:
Competition is an interaction between organisms or species in which both the organisms or species are harmed. Limited supply of at least one resource used by both can be a factor. This example is if two lions get into a fight and they end up hurting each other.
Exploitation competition occurs when individuals interact indirectly as they compete for common resources, like territory, prey or food. An example of this is when people are farming and they are trying to get the best food available but someone else might have already gotten it.
Commensalism is a positive type of ecological interaction between two species in an ecosystem. In commensalism, the association occurs between members of two different species where one species is benefited the other is neither benefited nor harmed. An example of this is tree frogs who use trees as protection.
Explanation:
A mutation that involves one or a few nucleotides is called
a) mutagen
b) inversion
c) point mutation
d) translocation
Answer:
c) point mutation
Explanation:
When only one or a few nucleotides of a gene are changed by mutation, this is called a point mutation. A point mutation can add one additional nucleotide to the wild type gene or may delete or substitute a nucleotide from it. For example, if a wild type gene sequence is "ATATATATA", then the addition of "C" at the position 4 will change it into "ATACTATATA". This addition of new nucleotide is called point mutation since only one nucleotide is added to the gene. Point mutations can cause serious genetic disorders such as sickle cell anemia.
