Answer:
Explanation:
Gas exchange occurs at the alveoli in the lungs and takes place by diffusion. The alveoli are surrounded by capillaries so oxygen and carbon dioxide diffuse between the air in the alveoli and the blood in the capillaries.
Answer:
Explanation:
Sister chromatids are regarded as replicated chromosomes. Sister chromatids are two identical copies of chromosomes held at the centromere that are formed as a result of replication. They are identical in the sense that they contain same alleles/gene sequence of the same genes.
Homologous chromosomes, on the other hand, are similar (in length, centromere position) but non-identical chromosomes. Homologous are non-identical in the sense that they may contain different alleles of a gene and are received from each parent. homologous chromosome contain four chromatids; two of which are sister chromatids and non-sister to the other two.
Both undergo meiosis where homologous chromosomes separate in meiosis I while sister chromatids separate in meiosis II but only sister chromatids undergo mitosis.