Ras is a GTP-binding protein involved in cell proliferation (division). In its active form, with GTP bound, Ras activates cell s
ignaling pathways that promote cell division. Mutations in the gene that encodes Ras can lead to cancer. How might mutations in the gene encoding Ras lead to the uncontrolled proliferation characteristic of cancer cells
Mutations in the active site induce a continue 'switch-on state' of the Ras proteins
Explanation:
Ras is a family of GDP/GTP-binding proteins expressed in all animal cells. Ras proteins play roles in signal transduction pathways, where they are activated to subsequently 'switched on' other proteins involved in diverse cellular processes including cell growth, cell differentiation and survival. In consequence, the Ras genes are considered to be oncogenes because when they are overexpressed in cells their encoded proteins produce uncontrolled cell proliferation, thereby leading to cancer progression.
Larger organism increases more in volume than area. That's why larger organism uses respiratory systems or organs and systems instead of simple diffusion for removal of waste and absorption of nutrients.
