Over the last several decades, the scientific community has gathered a large amount of information regarding genetics and genetic variation. what are two main sources that lead to increased genetic variation? . selective breeding . gamete mutations . recombination . genetic drift . i have looked all in my notes and can't find anything on this topic.

The right answer is Recombination AND Genetic drift

Recombination is an exchange of genetic information (strand of DNA) between two different sectors of the genome. A frequent example is the meiosis between homologous chromosomes (crossing over).

Genetic drift is the evolution of a population or species caused by random phenomena, impossible to predict. From the genetic point of view, it is the modification of the frequency of an allele, or of a genotype, within a population, independently of the mutations, the natural selection and the migrations. Genetic drift is caused by random and unpredictable phenomena, such as the chance of sperm and egg encounters, in the case of sexual reproduction.

the answer to this predicament is false, by friend, i had this on a quiz, and i got it wrong, so i learned it, cos i was gonna have it on a test, and i got it right

i think it would be b. tissue because an organ system is a group of organs that work together to perform one or more functions. each does a particular job in the body, and is made up of certain tissues.