Question

Which of the following statements about organelles is true?

1) Organelles contain their own DNA.
2) Organelles resemble present-day prokaryotes.
3) Organelle genomic sequences resemble those of present-day prokaryotes.
4) Organelles can divide independently from the cell nucleus.
5) Organelles are enclosed by double membranes.

Answer 1

Certain organelles, like mitochondria and chloroplasts, contain their own DNA, replicate independently, and some are enclosed by double membranes, supporting the endosymbiotic theory of eukaryotic cell evolution.

Step-by-step explanation:

True statements about organelles are:

1. Organelles contain their own DNA.
2. Organelle genomic sequences resemble those of present-day prokaryotes.
3. Organelles can divide independently from the cell nucleus.
4. Some organelles are enclosed by double membranes.

In eukaryotic cells, certain organelles such as mitochondria and chloroplasts contain their own DNA, which is distinct from the nuclear DNA. This DNA is often circular and shares similarities with the DNA of prokaryotes, which supports the endosymbiotic theory suggesting these organelles originated from prokaryotic cells that were engulfed by ancestral eukaryotic cells. Moreover, these organelles can replicate independently of the cell's nucleus, further resembling the autonomous nature of prokaryotes. While not all organelles have double membranes, the mitochondrion and chloroplast are examples of organelles that do. The double membrane structure is another characteristic shared with prokaryotic ancestors; it includes an outer membrane and an inner membrane, each with different functions and molecular compositions.