A. umbilical cord is the answer
Oxygen-16 and Carbon-12 are stableisotopes of elements O and C respectively. Hence, they do not have half-lives. But Carbon-14 andUranium-238 are radioactive isotopes. Among them Carbon-14 has relatively short half-life as about 5730 years while Uranium-238 has a long half-life as about 4.5 billion years.
Answer is. uranium-238
Answer:
Hey there the answer would be D. Keratin is the pigment responsable for skin color.
Explanation:
A. The top layer of the epidermus is made of dead skin cells. The inner player has to be constatnly making more cells
B.The body procudes more melanin with stronger sunlight exposure. This results because the UV of the sun causes T-T dimers which is a type of DNA damage.
C. UV causes genetic mutation which can result in cancer if not fixed by the cell
D.Keratin is found in the epidermis and with thick layer of skin found in the hands and feet. Melainin is responsible for skin color.
To answer this we would the answer choices.
The difference between sharks and bony fish is that sharks have skeletons made up of cartilage and dont have bones, while bony fish have bones
