The movement by diffusion of charged ions such as Na+ and Cl- across the plasma membrane is blocked by the lipid bilayer in the middle of the plasma membrane. true of false?

True.

Explanation:

As we know, the plasma membrane of the cells is semi-impermeable, that is, it only allows the passage of some molecules in sizes and specific burning nature. Although the Na + and Cl- molecules are very small, they are polar, electrically charged molecules. These molecules are not well seen by the membrane, which does not allow them to pass into the intracellular medium.

organisms that lack symmetry are called asymmetrical and belong to phylum porifera/sponges.

organisms with specialized stinging cells belong to phylum cnidaria. stinging cells are called cnidoblast cells.

cnidarians show two morphological forms : polyp (sessile) and medusa (mobile)

filter feeding is observed in porifera members.  

alternation of generation is observed in coelenterata or cnidaria. there is alternation of asexual polyp form and sexual medusoid form. it is also referred as metagenesis.

the answer is z.

the human body has five levels of organization. level 1: cells. cells are the basic units of life and form the first level of organization. cells in the human body have specific functions. examples include nerve cells, blood cells, liver cells, and so on.