Why Are Damaged Cells Replaced

Words: 1191
Pages: 5
Open Document
To understand how the damaged cells are replaced and how a 2n becomes n first we have to understand about the cell cycle.
Cell Cycle
Cell cycle is a cycle where all the cells passes a series of process in which a cell grows and divides. So this cell cycle is comprised of two periods
1. Interphase
2. The period of division
During interphase there are 3 stages that occur
1. G1- it is a stage where the cell grows. And also it is a period between the end of mitosis and start of DNA synthesis
2. S phase- it is a stage where the DNA replicates.
3. G2 phase- it is a stage where again the cell grows and it is a period between the end of DNA replication and start of mitosis.
Cell Cycle Checkpoint
Cell cycle contain check points. As we know the cell …show more content…
As same as G1 checkpoint, if there is any problem regarding the DNA then the cell cycle is stopped and the problem is solved either by completing the DNA replication or else repair the damaged DNA. But if everything is correctly replicated then CDKs signals the starting of mitotic division.
M Checkpoint
The M checkpoint happens close to the end of the metaphase of mitosis. The other name for M checkpoint is spindle checkpoint in light of the fact that it figures out if all the chromatids are accurately joined to the spindle microtubules. Since the partition of the chromatids during anaphase is an irreversible step, the cycle won't continue until the kinetochores of every pair of chromatids are immovably moored to no less than two spindle fiber emerging from inverse posts of the cell.
Now let's look at the M phase
"Mitosis and meiosis are the two ways in which the cell divide and reproduce. Meiosis is a process of cell division that result in producing 4 daughter cells, each possessing half the number of chromosomes of the original cell. And mitosis is a process of cell division that result in two genetically identical daughter cells developing from a single parent …show more content…
prophase 2
2. metaphase 2
3. anaphase 2
4. telophase 2
Meiosis 2 process is similar to mitosis.
First prophase 2 takes place where nuclear membrane disappears, centrioles moves to the each end of the pole. Then metaphase 2 occurs where spindle fiber joins to the centromeres and the chromosomes line up along the center of the cell. In anaphase 2 the centromeres splits and the fiber pulls the chromatids to each end of the pole. Finally the last step occurs that is telophase 2 where the nuclear envelop reappears and the cells gets separated. Therefore resulting in four haploid cells.
And again the process continues from interphase.
Cell Regulation
There are four types of cell regulations
• There are two major control switches for cell cycle which causes the cell to move from G1 to S or G2 to M. They are Cyclin Dependent Kinase (CDKs) and cyclin
• The progression through the cell cycle is triggered by MPF ( Maturation Promoting Factor)
• If the DNA is damaged then the cell cycle is stopped until it is repaired. So this is done by a protein called
Show More

Related Documents: Why Are Damaged Cells Replaced

Tissues to Tattoos Essay

external surfaces, line cavities and tubular structures, and serve essential fuctions (Martini & Bartholomew, 2012). Connective tissue provides a protective structural framework for other tissue types. It has three basic components, including specialized cells, extracellular protein fibers, and ground substance (Martini & Bartholomew, 2012). Muscle tissue is designed for contraction. The three types of muscle tissue are skeletal, cardiac, and smooth. Neural tissue responds to stimuli and conducts electrical…

Words 779 - Pages 4

Essay about Embryonic Stem Cell Research

1 28 October 2011 Embryonic Stem Cell Research The history of stem cell research had an embryonic beginning in the mid 1800’s with the discovery that some cells could generate other cells. An embryo is an organism in the early stages of development that cannot survive on its own because it lacks tissues, organs, and body structure. Today, stem cell research is a focus of a controversy over the use of embryonic stem cells for research. This is why we have chosen this topic to provide information…

Words 1015 - Pages 5

Cancer and Heart Disease: the Who, Why, and What of It Essay

Cancer and Heart Disease: The who, why, and what of it Com/155 Instructor: Janet Ward June 10, 2012 By: Brooke Bowman Cancer and Heart Disease: The who, why, and what of it Cancer and heart disease are the top two killers of Americans, but who is at the greatest risk; men or women and why? The first thing we must do to prevent ourselves from developing either of these deadly diseases,…

Words 1108 - Pages 5

Stem Cell Research Benefits

Embryonic stem cells may lead to a scientific breakthrough. Stem cell researchers should be able to use stem cells from aborted babies to cure diseases. More specifically, researchers should be allowed to use aborted babies that are within a certain week of development for stem cell research. Aborted babies are unwanted by the mother and father. Instead of killing the developing embryo and disposing them, we could use them to help other people. Embryonic stem cells are astonishing. They can help…

Words 690 - Pages 3

Essay on Stem Cells

Stem cells are the basic building blocks of life. They have the most amazing abilities and qualities, with the potential to become different types of cell in our bodies. That's why they offer us the greatest potential to treat conditions that affect us all. For many people in the general public, however, the topic is a confusing one and it can be difficult to understand and interpret information about stem cells. You may still be unsure just what stem cells are or what relevance they have to your…

Words 1002 - Pages 5

Chapter 3 Study Guide Essay

abundant and the most widely distributed of the tissues. Muscle tissue: skeletal, smooth, and cardiac. Nerve tissue is composed of specialized cells which not only receive stimuli but also conduct impulses to and from all parts of the body. 2. How are epithelial tissues classified? Epithelia are classified on the basis of cell shape and arrangement. 3. How does the type of epithelial tissue relate to its function? Give at least 1 example of where you would find each type…

Words 1253 - Pages 6

Extraarticular Ligament Healing Case Study

(Last paragraph from page156 of Fundamental Orthopedic Management book.) Compare intraarticular and extraarticular ligament healing. Intraarticular ligament does not healing naturally; it requires to dissolve hematoma formation at the ends of the damaged ligaments. While extraarticular ligaments enclose a highly structure in heal. How are the grades of ligament tears determined? Grade I: Microscopic ripping of the ligament which does not produce joint laxity. Grade II: Ligaments that present a moderate…

Words 1576 - Pages 7

Research Paper 4 24

others, mainly because of money. There are natural and proven ways to cure cancer and there are also ways that can be harmful. In the 1950s, Dr. Johanna Budwig presented a non-harmful, natural way to cure cancer cells with her diet protocol. Chemotherapy is another way to kill out cancer cells, but can be destructive on one’s body. Keeping a healthy lifestyle, unlike the majority of Americans today, is very important when it comes to battling and fighting cancer. There are alternative diets that have…

Words 961 - Pages 4

Pros And Cons Of Embryonic Stem Cells

could completely remap healthcare, or even cure cancer. Stem cells are the controversial talk of the town with super powers derived from morally ambiguous sources. Many points in this conversation explain the differnce between adult and embryonic stem cells, the widely debated moral status of the embryo, and most importantly, the changes gene therapy could potentially make in nearly every…

Words 1010 - Pages 5

Stem Cell Paralysis

Stem Cell Treatment Curing Paralysis Can improvements in stem cells lead to the cure of paralysis? Millions suffer from paralysis and are forced to live their lives suffering from not fitting in with other and being impaired from physical activity like those who are not paralyzed. We are trying to solve paralysis. We are doing this because this is an imminent problem. Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling (sensory loss)…

Words 1075 - Pages 5