|In dividing? OR non-dividing cells?||IN NON-DIVIDING CELLS||IN DIVIDING CELLS|
|Easy to read & copy? OR Easy to move?||EASY TO READ & COPY||EASY TO MOVE|
What are chromosomes made of?
Chromosomes are made up of a DNA-protein complex called chromatin that is organized into subunits called nucleosomes.
How do genes copy?
How is DNA replicated? Replication occurs in three major steps: the opening of the double helix and separation of the DNA strands, the priming of the template strand, and the assembly of the new DNA segment. During separation, the two strands of the DNA double helix uncoil at a specific location called the origin.
Why can chromosomes be seen only when a cell is dividing?
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.
Why are chromosomes visible during mitosis?
Chromosomes become visible during mitosis because they condense themselves to thick, visible strands. Regularly, they are more spread out as thin strands and therefore invisible to the eye even with a microscope.
How many DNA is in a chromosome?
One chromosome has 2 strands of DNA in a double helix. But the 2 DNA strands in chromosomes are very, very long. One strand of DNA can be very short – much shorter than even a small chromosome. Strands of DNA are made by joining together the 4 DNA bases in strings.
What happens when three genes are missing?
The deletion occurs at the end of the short (p) arm of the chromosome. This chromosomal change often leads to intellectual disability, developmental delay, and abnormal physical features. Individuals with 3p deletion syndrome typically have severe to profound intellectual disability.
What is gene example?
For example, if both of your parents have green eyes, you might inherit the trait for green eyes from them. Or if your mom has freckles, you might have freckles too because you inherited the trait for freckles. Genes aren’t just found in humans — all animals and plants have genes, too.
What three phases are individual chromosomes no longer visible?
It is during interphase, telophase, and cytokinesis that the chromosomes are no longer visible.