INTRODUCTION
CELL ORGANELLES
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Yes, all cells have a nucleus.
|
|
|
No, only eukaryotes have a nucleus.
|
|
|
No, only prokaryotes have a nucleus.
|
|
|
No, none of the types of cells contain a nucleus.
|
Detailed explanation-1: -While eukaryotic and prokaryotic cells both contain cytoplasm and a membrane that encloses the contents of the cell, only eukaryotes possess a membrane-bound nucleus. Prokaryotes, by contrast, have cells without a nucleus.
Detailed explanation-2: -No, the nucleus is not the only site of DNA in a eukaryotic cell. Certain organelles, including the mitochondrion and chloroplast, contain their own DNA. The DNA found in these organelles is smaller than genomic chromosomes and it is circular as opposed to linear.
Detailed explanation-3: -Eukaryotic cells are found in plants, animals, fungi, and protists. They generally have a nucleus-an organelle surrounded by a membrane called the nuclear envelope-where DNA is stored. There are a few exceptions to this generalization, such as human red blood cells, which don’t have a nucleus when mature.
Detailed explanation-4: -Not every cell in the human body contains DNA bundled in a cell nucleus. Specifically, mature red blood cells and cornified cells in the skin, hair, and nails contain no nucleus.