Mitosis

Human cells contain 46 chromosomes before mitosis. How many do they have after mitosis?

46

What are the main events that occur during interphase?

Interphase - growth of cell, preparation for division, and replication of DNA o G1 - growth of cell in size (expansion of cytoplasm); duplication of organelles, lipids, CHOs, proteins G1 checkpoint - (most important checkpoint) cell size is appropriate, sufficient nutrients, no DNA damage, favorable environment to start replicating DNA, presence of growth factors; if not signal, cell enters G0 o S - DNA is replicated (synthesized) o G2 cell gets ready to divide, continues to duplicate organelles, proteins, lipids, etc G2 checkpoint - if DNA replication is complete, no DNA damage identified, and the environmental is favorable, cell can proceed to M phase

Using the first letter of each stage, the correct order of the stages of mitosis are

PMAT

During anaphase, what structures are attached to the centromeres?

Spindle Fibers

Chromatids move to opposite poles of a cell during anaphase and telophase. What appears to be the mechanism for the pulling action?

The spindle fibers, attached to the centromeres, pull the sister chromatids apart. Specifically, motor proteins of the kinetochores (powered by ATP) walk the newly separated daughter chromosomes centromere-first along the microtubules toward opposite poles of the cell.

Describe the function of the centriole in animal cells

To produce spindle fibers and help separate the chromosomes

How can you tell whether cells in mitosis are animal cells or plant cells?

Yes. Look for shape of cell and presence of cell wall

The stage of mitosis where sister chromatids separate is

anaphase

During interphase, when the DNA is in long thin strands and is not yet visible, DNA is

chromatin

The cells that result from mitosis are called

daughter cells

When do chromosomes become visible in mitosis?

early prophase

When does the nuclear membrane dissolve/disappear in mitosis?

end of prophase

The phase of cell cycle where the cell grows is

interphase

The stage during which the chromosomes are replicated/copied is:

interphase

The stage of mitosis where chromosomes line up along the center is

metaphase

Nuclear division is

mitosis

The stage where the nuclear membrane disappears and chromosomes begin to appear is

prophase

The stage of mitosis where the nuclear membrane reappears is

telophase