Question

1. what is the definition of selective permeability?

it is the property of the plasma membrane that allows it to control movement of substances
into or out of the cell.
it moves needed substances or waste materials through the plasma membrane.
it is the process of maintaining balance in an organisms internal environment.
it is layers composed of phospholipid molecules arranged with polar heads facing outside
and non - polar tails facing the inside.

1. describe the movement of oxygen molecules if there were more oxygen molecules outside the cell.

explain your answer.

Explanation:

• Question 7:
• Selective permeability is a property of the plasma membrane. The plasma membrane controls the movement of substances into or out of the cell.
• Option 2 describes the movement of substances (needed substances or waste materials) through the plasma membrane, which is related to the function enabled by selective permeability. But the key is that selective permeability is the property that allows this control.
• Option 3 is about homeostasis (maintaining internal balance), Option 4 is about the structure of the phospholipid bilayer.
• Question 8:
• Oxygen molecules move by simple diffusion. Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration.
• If there are more oxygen molecules outside the cell (higher concentration outside), oxygen will move into the cell (down its concentration gradient) until equilibrium (equal concentration inside and outside, or until other factors like cellular respiration consume the oxygen inside the cell and maintain a concentration gradient) is reached.

Answer:

• Question 7: The first option "It is the property of the plasma membrane that allows it to control movement of substances into or out of the cell" is the correct definition of selective permeability.
• Question 8: Oxygen molecules would move into the cell. Because of simple diffusion (movement from high - concentration area (outside the cell) to low - concentration area (inside the cell)).