Answer:
Explanation:
The main function of the plasma membrane is to protect the cell from its surroundings. Made of a phospholipid bilayer with embedded proteins, the plasma membrane is selectively permeable to ions and organic molecules it also regulates the movement of substances in and out of cells. Plasma membranes must be very flexible in order to allow certain cells, such as red blood cells and white blood cells, to change shape as they pass through narrow capillaries. Membrane receptors provide extracellular attachment sites for effectors like hormones and growth factors, which then trigger intracellular responses. Some viruses, such as Human Immunodeficiency Virus (HIV), can intercept these receptors to get into the cells, causing infections.
Answer:Oxygen
Explanation: During cellular respiration, glucose is broken down in the presence of oxygen to form carbon dioxide, water and energy. Glucose + oxygen --> carbon dioxide + water + energy.
The balanced chemical equation for cellular respiration is C6H12O2 + 6O2 --> 6CO2+ 6H2O + Energy
Thin, flexible barrier around a cell; regulates what enters and leaves the cell
- contains the cytoplasm (all interior cell organelles and the cytosol) - allowing the chemical reactions in the cell to occur
<span>- semipermeable (or selectively permeable) - allows certain substances in, keeps others out </span>
<span>- offers limited protection</span>
