Answer:
Semi-permeable membrane
Explanation:
In semi-permeable membranes, only some substances can pass through. Sometimes, some can also pass through the channel protein molecules or transport proteins on the cell membrane.
Given the age of the meteorite is 4.5 billion years old with 78 atoms of lead-206 the answer should be B. 156. The half-life of uranium-238 in order to decay into lead-206 is 4.46 billion years, which means that the original number of atoms is 156.
There are four main types of tissue: muscle, epithelial, connective and nervous. Each is made of specialized cells that are grouped together according to structure and function. Muscle is found throughout the body and even includes organs such as the heart. Our outer layer of skin is epithelial tissue.