Answer:
They look like X's (X shape)
Explanation:
The X shape are replicated chromosomes and are called the sister chromatids.
Robert hook is the one recognized vital role of the in internal environment and observers
Answer:
antibodies are produced in response to infection and that these antibodies are designed to specifically target particular antigens and bind tightly to them.
I'm not positive but i believe it would be a ruler with millimeters and centimeters