Answer:
You can measure mineral hardness with The Mohs' Scale.
Hope this helped :)
Answer:
They help to stop harmful germs from entering the body
Explanation:
- The skin can prevent bacteria and microorganisms from entering the body (unless it is damaged)
- Mucous membranes line the mouth and nose and are coated with secretions that fight microorganisms and harmful bacteria
- Tears help to clear debris from the eye to prevent infection
Answer:
Yes. Cells have 'cell receptors' that are used to receive messengers like hormones to communicate. Cell receptors have specific shapes that fit the shape of the messenger that they want to receive. Organs like the pancreas send our these messengers to the cells to order them to do different functions.
Answer:
The first bullet point is correct
Explanation:
The cell membrane controls what comes in and out of the cell, it needs minerals so would not block them completely, and water does not enter cells so it is clearly the first one.
A) 100% red pigment
b) 75% black pigment
c) 25% of offspring is expected to lack both red and black pigments in their skin