when a cell divides it course hero

Why do cells divide in the body?

Cell Division Signaling Most cells in the body are not actively dividing, but are carrying out their normal functions. Cells divide in response to external signals in the form of protein or steroid growth factors. Cells stop dividing for several reasons, including: A lack of positive external signals

How is cell division controlled?

Cell Division Control Cell division is a normal process. Mechanisms exist to ensure DNA replication occurs correctly and the environmental conditions are favorable for cell division. Normal cells stop dividing when there is genetic damage or conditions are not favorable.

How do cells know when to stop dividing?

For instance, if a cell senses that it is surrounded on all sides by other cells, it will stop dividing. In this way, cells will grow when needed but stop when their goal has been met.

Is cell division a normal process?

1 Cell division is a normal process. 2 Mechanisms exist to ensure DNA replication occurs correctly and the environmental conditions are favorable for cell division. Replication errors may also be corrected after they occur. 3 Normal cells stop dividing when there is genetic damage or conditions are not favorable. ...

When a cell is not dividing, the chromatin is enclosed within a clearly defined nuclear envelope?

When a cell is not dividing, the chromatin is enclosed within a clearly defined nuclear envelope, one or more nucleoli are visible within the nucleus, and two centrosomes (each containing two centrioles) lie adjacent to one another outside the nuclear envelope.

Why does DNA control the cell?

DNA controls the cell in this manner because it contains codes for polypeptides. Many polypeptides are enzymes that regulate chemical reactions and influence the resulting characteristics of the cell. Thus, from the molecular viewpoint, traits are the end products of metabolic processes regulated by enzymes.

How does Anaphase II start?

Anaphase II begins as each chromosome is pulled apart into two chromatids by the microtubules of the spindle apparatus. The chromatids (now chromosomes) migrate to their respective poles. Again, this is exactly what happens in mitosis—except now there is only half the number of chromosomes.

What is the name of the chromosomes that separate into a chromosome?

Each chromatid is complete with a centromere and kinetochores. Once separated from its sister chromatid, each chromatid is called a chromosome. (To count the number of chromosomes at any one time, count the number of centromeres.) Anaphase begins after the chromosomes are separated into individual chromatids.

What happens at the end of anaphase?

At the end of anaphase, each pole has a complete set of chromosomes, the same number of chromosomes as the original cell. (Since it consists of only one chromatid, each chromosome contains only a single copy of the DNA molecule.) Telophase concludes the nuclear division.

What is the first step in mitosis?

The first step in either mitosis or meiosis begins with the condensation of the genetic material, chromatin, into tightly coiled bodies, the chromosomes. Each chromosome is made of two identical halves called sister chromatids, which are joined at the centromere.

What is the difference between nuclear division and cytokinesis?

Nuclear division divides the genetic material in the nucleus, while cytokinesis divides the cytoplasm. There are two kinds of nuclear division—mitosis and meiosis. Mitosis divides the nucleus so that both daughter cells are genetically identical. In contrast, meiosis is a reduction division, producing daughter cells that contain half ...

Why are there safeguards built into the cell division process?

There are several safeguards built into the cell division process to assure that cells do not divide unless they have completed the replication process correctly and that the environmental conditions in which the cells exist are favorable for cell division. Among others, there are systems to determine the following:

What is the process by which a cell reproduces to create two identical copies of itself?

The process by which a cell reproduces to create two identical copies of itself is known as mitosis. The portion of the cell cycle (M stage) during which a cell divides into two (usually identical) daughter cells. . The goal of mitosis is the formation of two identical cells from a single parent cell.

What happens to telomerase during DNA replication?

Normally, during DNA replication, chromosome ends are shortened by a small amount. Telomerase is turned off in most adult tissues, a process that limits the number of cell divisions that can be completed by those cells. In cancer cells, telomerase is often reactivated, allowing the cells to divide indefinitely.

What is the cytoplasm?

The portion of a cell that is located outside the nucleus. This includes many organelles such as ribosomes and mitochondria. The cytoplasm also contains many fibers of the cytoskeleton. of the cell must be physically separated into two different cells.

What is the term for the round containers in which cells are depicted in the animations?

The round containers in which the cells are depicted in the animations are called petri dishes. In the laboratory, cells are often grown in these, covered with a nutrient-rich liquid. Cellular Senescence. In the context of cell division, the term refers to the aging and death of a culture of cells.

What is the name of the cell that is formed from DNA?

The cells formed are known as daughter cells. In order for this to happen, the following must occur: The genetic material, the DNA. Abbreviation for deoxyribonucleic acid. Composed of very long strings of nucleotides, which are abbreviated as A, C, G and T. DNA is the storage form of our genetic material.

What is the role of nuclear pores in cell division?

The nuclear pores allow for the import and export of materials. . The result is that the genes responsible for cell division are turned on and the cell divides. For example, a cut in the skin leads certain blood cells, platelets, to produce a growth factor (that causes the skin cells to reproduce and fill the wound.