Evolution used to be an argument against evolution and Darwin's theory was important for convincing people otherwise. He made five observations and three inferences regarding natural selection which helped his theory become widely accepted.
Answer:
Ozone (O₃) gas
Explanation:
In the Earth's stratosphere, oxygen gas (O₂) is combined with atomic oxygen (O) to form ozone gas (O₃). This is very important because ozone protects the life on Earth from ultraviolet (UV) radiation from the Sun. UV radiation is high-energy radiation, and it is very dangerous for living organisms. Ozone molecule (O₃) absorbs UV radiation and it breaks down by forming O₂ and atomic oxygen (O) again. In this way, it protects the Earth from nocive radiation.
B. Arteries have a thicker tunica media than veins
The statements are true.
Hemoglobin (Hb), is the oxygen-transport metalloprotein which contains iron in the centre of its structure. This metalloprotein is found in the red blood cells (erythrocytes). The function of hemoglobin is to transport the oxygen through the blood carries from the lungs to the rest of the tissues. Oxygen is necessary for the aerobic respiration in order to provide energy for the functions of the organism (metabolism).