Dna is responsible for your phenotype, but to what extent? how much, if at all, do environmental factors play a role? can you find examples (remember keep your sources academic)?

Environment DOES influence gene expression and phenotype of an organism to some extent. If you search google or google scholar for articles with keywords like "Environment affecting phenotype" or similar wording you'll come across many academic studies.

Explanation:

a chair, a bed, and a toothbrush

explanation:

i was told this before by a teacher, so yeah

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.