It’s cell wall and chloroplast. We don’t need chloroplast because we don’t make our own food.
Answer:
Cholesterol is a structural component of the cell membranes of animals. Because of cholesterol that provides cell membrane structural integrity and fluidity, animal cells need not to have cell walls such as that in bacterial and plant cells.Cholesterol reduces permeability of lipid membranes. ... Cholesterol plays has a role in membrane fluidity but it's most important function is in reducing the permeability of the cell membrane. Cholesterol helps to restrict the passage of molecules by increasing the packing of phospholipids.
Explanation:
Answer: By definition, if the atomic number =
7
, then there are 7 protons, 7 electrons, and 8 neutrons!
Explanation:
The atomic number is by definition the number of protons, positively charged particles, contained within the atomic nucleus. So if there are 7 protons, there MUST be 7 electrons, 7 negatively charged particles. Why? Because matter is electrically neutral, and positive and negative particles must be equal.
Electrons have negligible mass; the mass number depends on the number of protons contained within the nucleus, PLUS the number of neutrons. Given that we have 15 N
, there must be 8 neutrons contained within the nucleus. does this help?
Circulatory system.....circulates blood (a vital delivery system of oxygen) throughout the whole body when tissues need it the most and with a constant supply.