Video Transcript
Which of the following statements
correctly describes what parts of the human body can be damaged by absorbing nuclear
radiation? (A) Only skin, hair, eyes, and
other external body parts can be damaged. (B) Only blood cells can be
damaged. (C) All parts of the body can be
damaged.
This question is asking us to
identify what parts of the human body can be damaged by nuclear radiation that is
absorbed by the body.
Recall that there are different
categories of nuclear radiation and that these different categories can enter the
human body in different ways. Some types of nuclear radiation can
penetrate the skin. When this occurs, the nuclear
radiation can be directly absorbed by internal organs. Some types of nuclear radiation
cannot penetrate the skin. When this occurs, the nuclear
radiation is instead absorbed by the skin. A source of nuclear radiation may
be unintentionally swallowed or inhaled. This allows nuclear radiation to be
absorbed inside the body even if it cannot penetrate the skin. This is very dangerous as internal
organs can be fatally damaged by nuclear radiation.
All living organisms, including
humans, are made of cells. These cells can be in the skin or
in internal organs. Nuclear radiation can transfer
energy to the cells of a living organism. The two main energy transfers to
cells that have absorbed nuclear radiation are thermal energy and chemical
energy.
Chemical energy transferred to a
cell by nuclear radiation causes chemical reactions. These chemical reactions change the
normal function of cells and can cause the following symptoms: blindness, hair
falling out, internal bleeding, organ failure.
When thermal energy is transferred
to a cell by nuclear radiation, energy is dissipated in the cell. If this energy dissipation occurs
in cells of the skin, the effect is similar to sunburn. When going outside without
protection, our skin will absorb the Sun’s radiation and can become red and
burnt. The Sun, a source of nuclear
radiation, has transferred thermal energy to the cells in our skin. Different categories of nuclear
radiation can transfer thermal energy to cells beneath the skin.
We have stated that when chemical
energy is transferred to cells, blindness and hair loss can occur. Hence, hair and eyes are damaged by
absorbing nuclear radiation. We have also stated that cells in
skin can absorb nuclear radiation and that thermal energy transferred to the cell
causes burns. Hence, option (B), which states
that only blood cells can be damaged, cannot be the correct answer. Blood cells are under our skin in
different parts of the body.
We have said that some categories
of nuclear radiation can penetrate the skin. We have also said that nuclear
radiation can transfer energy to cells. Option (A) cannot be the correct
answer as blood cells are a type of cell, so they can be damaged by this penetrating
radiation.
Therefore, the correct answer must
be (C). All parts of the body can be
damaged.
