Which of the following choices gives the correct cell structure from outermost to innermost layer?
A. Cytoplasm, nucleus, nucleolus, cell membrane
B. Nucleolus, nucleus, cytoplasm, cell membrane
C. Cell membrane, cytoplasm, nucleus, nucleolus
D. Cell membrane, nucleolus, nucleus, cytoplasm
To determine the correct answer, we need to understand the structure of a typical eukaryotic cell. Here's an explanation on how to get the answer:
A eukaryotic cell is composed of several structures organized in a particular order. Let's go through each choice one by one:
A. Cytoplasm, nucleus, nucleolus, cell membrane
The cytoplasm is the jelly-like substance that fills the cell. It is located between the nucleus and the cell membrane. The nucleus is the central organelle that holds the cell's genetic material. Inside the nucleus, there is a smaller structure called the nucleolus, which is involved in the production of ribosomes. Cell membrane forms the outer boundary of the cell.
B. Nucleolus, nucleus, cytoplasm, cell membrane
This choice is incorrect because the nucleolus is a structure found inside the nucleus. So, it cannot come before the nucleus in the sequence.
C. Cell membrane, cytoplasm, nucleus, nucleolus
According to this choice, the cell membrane forms the outermost layer. Next comes the cytoplasm, followed by the nucleus, and finally the nucleolus. This sequence is correct because the cell membrane surrounds the entire cell, the cytoplasm fills the area inside the cell membrane, the nucleus is suspended in the cytoplasm, and the nucleolus is found within the nucleus. Therefore, option C is the correct answer.
D. Cell membrane, nucleolus, nucleus, cytoplasm
This choice is incorrect because the nucleolus is located within the nucleus. So, it cannot come before the nucleus in the sequence.
Therefore, the correct answer is C. Cell membrane, cytoplasm, nucleus, nucleolus.