Answer: The Answers are, A: happens all the time, D: can be caused by genetic drift, and E: can be caused by natural selection.
In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.
Chromosomes are not visible in the cell’s nucleus—not even under a microscope—when the cell is not dividing. However, the DNA that makes up chromosomes becomes more tightly packed during cell division and is then visible under a microscope. Most of what researchers know about chromosomes was learned by observing chromosomes during cell division.
The right answer is Ribosomes
The ribosome is a complex composed of RNA and ribosomal proteins, associated with a membrane (in the granular endoplasmic reticulum) or free in the cytoplasm. Common to all cells (prokaryotes and eukaryotes), the ribosome (and especially its composition) varies according to the organisms, even if it is always composed of two distinct subunits.
The ribosome is a huge ribonucleoprotein complex that allows the translation of mRNAs into proteins.
It gives birds a place to live because they create wholes. They also keep black cherry from proliferating.