Question

what is the primary role of the cell membrane in an animal cell?
a. producing energy for the cell.
b. acting as a semi - permeable barrier to control what enters and exits the cell.
c. housing the cells dna.
d. synthesizing proteins.
which of the following organelles is responsible for energy production in the cell?
a. mitochondria
b. nucleus
c. ribosomes
d. golgi apparatus

Explanation:

• For the first question: The cell membrane is a semi - permeable barrier. It controls the movement of substances (such as ions, nutrients, and waste) in and out of the cell. Mitochondria produce energy (so option a in the first question is wrong), the nucleus houses DNA (option c in the first question is wrong), and ribosomes synthesize proteins (option d in the first question is wrong).
• For the second question: Mitochondria are known as the "powerhouses" of the cell. They generate adenosine triphosphate (ATP) through cellular respiration. The nucleus contains the cell's genetic material (so option b is wrong), ribosomes are involved in protein synthesis (option c is wrong), and the Golgi Apparatus modifies, sorts, and packages proteins and lipids (option d is wrong).

Answer:

1. B. Acting as a semi - permeable barrier to control what enters and exits the cell.
2. A. Mitochondria