The structure of plasma membrane makes it selectively permeable allowing it to regulate the passage of substances into and out of the cell. Small nonpolar molecules can easily across the phospholipid bilayer of plasma membrane because it is hydrophobic. Polar molecules and ion cannot easily across the hydrophobic portion of plasma membrane because it is hydrophilic. Polar molecules and ions usually across the plasma membrane with the help of transport proteins.
The answer to 3 is B. Moon
Answer: cellular metabolism
Explanation:
Cellular metabolism is chemical reactions that takes place in living organisms so that they will be able to maintain life. Cellular metabolism is made up of thousands of genes, metabolites and proteins.
Cellular metabolism is affected by the sympathetic nervous system but is not affected by the parasympathetic nervous system.
Answer:
Chromosomes become visible, crossing-over occurs, the nucleolus disappears, the meiotic spindle forms, and the nuclear envelope disappears.
Explanation:
The duplicated homologous chromosomes pair, and crossing-over (the physical exchange of chromosome parts) occurs.
