The processes of and generate variation within the species, and ___ produces adaption to the environment.

1. mutation 2. sexual reproduction 3. natural selection

Explanation:

The process of mutation is responsible for genetic variation in which entirely new alleles is created in a population due to random fertilization, recombination and random mating between homologous chromosomes during meiosis that allows the shuffeling of alleles within offspring.

Sexual reproduction also contribute to variation in species as it may include mating of two different species producing a new species having cgaracteristic two different organisms.

Natural selection is the process that produces adapation to the environment. Natural selection over generationsallows changes in traits by which species change over time in response to changes in environmental conditions and support adaptation.

Hence, the correct answers for the balnks in sequential order are 1. mutation 2. sexual reproduction 3. natural selection.

the oxygenated blood then leaves the lungs through pulmonary veins, which return it to the left heart, completing the pulmonary cycle. this blood then enters the left atrium, which pumps it through the mitral valve into the left ventricle. from the left ventricle, the blood passes through the aortic valve to the aorta.

deoxygenated blood leaves through the right ventricle through the pulmonary artery. from the right atrium, the blood is pumped through the tricuspid valve (or right atrioventricular valve), into the right ventricle.