Schwann stated that all animals are made of cells, but animals are made of many different types of cells. For example, there are three different types of cells that make up three different types of muscle tissue in humans. How could you prove these were all “cells” even though they look different and make different tissues? Please help!

In biology, cell theory is the historic scientific theory, now universally accepted, that living organisms are made up of cells, that they are the basic structural/organizational unit of all organisms, and that all cells come from pre-existing cells. Cells are the basic unit of structure in all organisms and also the basic unit of reproduction

option a is correct i.e.

explanation:

in context to the membrane of nerve impulse, the outer membrane of neuron is semi permeable that is only sodium ions can pass through the membrane i.e. smaller ions can pass through the membrane while larger ions cannot pass through it.

that scientist would be robert hooke