Table of Contents
- 1 What is the form of the chromosomes in prophase?
- 2 What other changes occur during prophase?
- 3 What does a duplicated chromosome mean?
- 4 What does each duplicated chromosome have two of?
- 5 Where are chromosomes duplicated?
- 6 What occurs during chromosome duplication?
- 7 Why are there two copies of each chromosome during prophase?
- 8 Where do chromosomes move in the cell during anaphase?
What is the form of the chromosomes in prophase?
During prophase, the complex of DNA and proteins contained in the nucleus, known as chromatin, condenses. The chromatin coils and becomes increasingly compact, resulting in the formation of visible chromosomes. Chromosomes are made of a single piece of DNA that is highly organized.
What are replicated chromosomes called?
Before anaphase begins, the replicated chromosomes, called sister chromatids, are aligned at along the equator of the cell on the equatorial plane. The sister chromatids are pairs of identical copies of DNA joined at a point called the centromere.
What other changes occur during prophase?
During prophase the nucleoli disappear and the chromatin fibers thicken and shorten to form discrete chromosomes visible with the light microscope. Each replicated chromosome appears as two identical chromatids joined at the centromere.
Which of the following in the cell is duplicated during mitosis?
During interphase, the cell grows and the nuclear DNA is duplicated. Interphase is followed by the mitotic phase. During the mitotic phase, the duplicated chromosomes are segregated and distributed into daughter nuclei. The cytoplasm is usually divided as well, resulting in two daughter cells.
What does a duplicated chromosome mean?
The term “duplication” simply means that a part of a chromosome is duplicated, or present in 2 copies. This results in having extra genetic material, even though the total number of chromosomes is usually normal.
What is a duplicated chromosome made of?
A replicated chromosome (or equivalently, a duplicated chromosome) contains two identical chromatids, also called sister chromatids. A duplicated chromosome therefore includes two identical strands joined along their length at corresponding lengths of DNA.
What does each duplicated chromosome have two of?
each DUPLICATED chromosome has two sister chromatids. The two chromatids each contin an identical DNA molecule and are attached by cohesins which is a protein complex. – also known as sister chromatid cohesion. Before duplication each chromosome has a single DNA molecule.
What is it called when chromosomes appear?
prophase. a cell division begins, the chromatin threads coil and shorten so that visible bar like bodies (chromosomes) appear.
Where are chromosomes duplicated?
Explanation: DNA replication (and thus chromosome duplication) occurs during the interphase , the part of the cell cycle in which the cell is not dividing. It is important to know that the interphase is not part of mitosis.
When chromosomes duplicate the copies are?
Because each chromosome was duplicated during S phase, it now consists of two identical copies called sister chromatids that are attached at a common center point called the centromere.
What occurs during chromosome duplication?
The process of creating two new cells begins once a cell has duplicated its chromosomes. In this state each chromosome consists of a joined pair of identical replicas called chromatids. The chromosomes condense and line up across the center of the nucleus. The membrane surrounding the nucleus fragments and disappears.
What does duplicated chromosomes mean?
Why are there two copies of each chromosome during prophase?
Since each of the parent cell’s chromosomes were replicated during interphase, there are two copies of each chromosome in the cell during prophase. Once the chromatin has condensed into individual chromosomes, the genetically-identical chromosomes come together to form an “X” shape, called sister chromatids.
What kind of DNA is a replicated chromosome made of?
Chromosomes are made of a single piece of DNA that is highly organized. The replicated chromosomes have an X shape and are called sister chromatids. The sister chromatids are pairs of identical copies of DNA joined at a point called the centromere.
Where do chromosomes move in the cell during anaphase?
Spindle fibers (microtubules) are visible. In anaphase, the paired chromosomes (sister chromatids) separate and begin moving to opposite ends (poles) of the cell. Spindle fibers not connected to chromatids lengthen and elongate the cell. At the end of anaphase, each pole contains a complete compilation of chromosomes.
Where does the mitotic spindle form during prophase?
During prophase, the mitotic spindle begins to form outside the nuclear envelope from microtubule organizing centers (MTOCs), which are sometimes called centrosomes or centrospheres (see Chapter 11 ). In the fungi, the centrosomes are known as spindle pole bodies ( Aist and Williams, 1972 ).