Check for Understanding

Answer the following questions to see how much you know about radiation.

1. What is DNA, and what does it do?
   
   DNA stands for deoxyribonucleic acid. It is your genetic code and is responsible for instructing or programming every cell function.
   
   
2. What is the difference between a gene and a chromosome?
   
   A gene is a segment of a DNA strand that programs a cell for a specific job or characteristic. Some genes determine your hair color, eye color, the length of your bones (height), etc. A chromosome is a structure in the cell nucleus that is made up of genes.
   
   
3. What is a mutation?
   
   A mutation is any change, in this case a change in DNA structure in the cell. This would cause a change in cell function and that change would be passed along to the new cell when the mutated cell reproduces.
   
   
4. What is the danger to the astronauts of receiving too much radiation during a solar storm?
   
   Radiation can change, or mutate, the DNA in the astronaut’s cells. This could disrupt cell function, cause more mutated cells to be reproduced, and possibly lead to cancer.
   
   
5. What types of body cells are particularly susceptible to harmful radiation?
   
   Cells found in the spleen, liver, and lymph nodes, bone marrow, skin, and kidney.