Mitosis and the Cell Cycle
| Question | Answer |
|---|---|
| (mitosis) kinetochores are motionless in relation to poles of cell | metaphase |
| (mitosis) spindle microtubules disassemble | telophase |
| (mitosis) kinetochores move toward poles of cell | anaphase |
| (mitosis) cohesins break down | anaphase |
People also ask, where do the spindle microtubules attach?
Centrioles begin moving to opposite ends of the cell, and microtubules extend from the centrioles and begin to attach to the centromeres of chromosomes. Eventually, the microtubules extending from centrioles on opposite poles of the cell attach to every centromere and develop into spindle fibers.
Likewise, during what phase does the spindle form? prophase
Hereof, in which phase of mitosis do spindle microtubules shorten?
anaphase
In which phase of mitosis does spindle microtubules attach to kinetochores quizlet?
1. During prophase, microtubules of the miotic spindle lenghten. 2. During anaphase, the nonkinetochore microtubules lengthen and move fast past each other,and the kinetochore microtubules shorten.
14 Related Question Answers Found
What are spindle microtubules?
The spindle microtubules are protein fibers made up of as many as 45 different proteins that grow from the centrioles. They form a polymer, which is a large molecule made up of many similar molecules linked together.
What does a spindle do?
Spindle fibers form a protein structure that divides the genetic material in a cell. The spindle is necessary to equally divide the chromosomes in a parental cell into two daughter cells during both types of nuclear division: mitosis and meiosis. During mitosis, the spindle fibers are called the mitotic spindle.
How does the spindle apparatus form?
The structure of the spindle apparatus is mainly formed by the polar microtubules. During metaphase, the kinetochore microtubules align the chromosomes in the middle of the cell. During anaphase, the kinetochore microtubules pull the sister chromatids to opposite ends of the spindle poles.
What phase do spindle fibers disappear?
telophase
What anchors the spindle?
The centriole is an organelle that forms during interphase (growth period) and is that anchor for the spindle fibers and helps shorten the spindle during anaphase to pull apart chromosomes and move them to the opposite ends of the cell.
When and how is the spindle formed?
PROPHASE: During the prophase the nucleoli in the nucleus disappear. The chromatin fibers become tightly ccoiled and condense into chromosomes. Chromosomes line up in pairs and are joined at the centromere. In the cytoplasm, the spindle fibers begin to form and are made of microtubules.
What is the difference between microtubules and spindle fibers?
Long protein fibers called microtubules extend from the centrioles in all possible directions, forming what is called a spindle. Other microtubules bind to the chromosome arms or extend to the opposite end of the cell.
What would happen without spindle fibers?
What would happen if spindle fibers failed to form in a cell during mitosis? The cell would not be able to separate the chromosomes into two sets. If cytokinesis occured, the result would be one cell with two sets of chromosomes and one cell with none.
What is the process of meiosis?
Meiosis is a process where a single cell divides twice to produce four cells containing half the original amount of genetic information. These cells are our sex cells – sperm in males, eggs in females.
What is the purpose of meiosis?
Meiosis, on the other hand, is used for just one purpose in the human body: the production of gametes—sex cells, or sperm and eggs. Its goal is to make daughter cells with exactly half as many chromosomes as the starting cell.
Why is Prometaphase important?
prometaphase. During prometaphase, the physical barrier that encloses the nucleus, called the nuclear envelope, breaks down. The breakdown of the nuclear envelope frees the sister chromatids from the nucleus, which is necessary for separating the nuclear material into two cells.
What is the longest phase of the cell cycle?
G1 is typically the longest phase of the cell cycle. This can be explained by the fact that G1 follows cell division in mitosis; G1 represents the first chance for new cells have to grow. Cells usually remain in G1 for about 10 hours of the 24 total hours of the cell cycle.
What are the steps in mitosis?
Stages of mitosis: prophase, metaphase, anaphase, telophase. Cytokinesis typically overlaps with anaphase and/or telophase. You can remember the order of the phases with the famous mnemonic: [Please] Pee on the MAT.
What do spindle fibers attach to?
Spindle fibers move chromosomes during cell division by attaching to chromosome arms and centromeres. A centromere is the specific region of a chromosome where duplicates are linked. Identical, joined copies of a single chromosome are known as sister chromatids.