Mitosis

Cell Theory

All cellular life is made of one or more cells; cells are the smallest unit of life; all cells come from other cells.

Terminally Differentiated Cells

Cells that do not divide, such as erythrocytes and neurons.

Cell Division

The process of reproduction in living cells; in unicellular organisms, it is solely for reproduction, while in multicellular organisms it supports growth, development, renewal, and repair.

Genome

A cell's total genetic material, predominantly found in the nucleus.

Prokaryotes

Cells that typically have one circular DNA molecule.

Eukaryotes

Cells that generally contain multiple linear DNA molecules.

Chromosome

A molecule of DNA in a cell; found in both eukaryotic and prokaryotic cells.

Nucleosomes

DNA-wrapped structures consisting of eight histones.

Chromatin

DNA/protein complex in a dispersed state; the lowest density form of DNA packaging.

Gene

An informational unit of DNA that contains the information to make proteins.

Locus

The specific location of a gene on a chromosome.

Haploid (n)

Having one complete set of chromosomes, typical of gametes.

Diploid (2n)

Having two complete sets of chromosomes; somatic cells in humans are diploid.

M Phase

The phase of the cell cycle where cell division occurs.

Interphase

The phase of the cell cycle where cells grow and conduct metabolic functions; accounts for 90% of the cell cycle.

G1 Phase

The first gap phase of interphase where the cell grows and prepares for DNA synthesis.

S Phase

The phase of the cell cycle where DNA synthesis occurs and chromosomes are duplicated.

G2 Phase

The second gap phase, where the cell prepares for mitosis and high metabolic activities occur.

Sister Chromatids

Identical copies of DNA connected at the centromere after DNA replication.

Kinetochore

A protein structure that attaches to the centromere of chromosomes and interacts with microtubules during cell division.

Mitosis

The process of nuclear division in somatic cells, comprising four stages: prophase, metaphase, anaphase, and telophase.

Prophase

The first stage of mitosis where chromosomes condense, the mitotic spindle forms, and the nuclear envelope breaks down.

Metaphase

The stage of mitosis where chromosomes align at the metaphase plate.

Anaphase

The stage of mitosis where sister chromatids separate and move to opposite poles of the cell.

Telophase

The final stage of mitosis where chromosomes de-condense and the nuclear envelope reforms.

Cytokinesis

The process of cytoplasmic division that typically overlaps with telophase to form two daughter cells.

What is the order of the steps in Mitosis?

The order of mitosis is Prophase, Metaphase, Anaphase, and Telophase.

Why is Prophase important in Mitosis?

Prophase is important because it prepares the chromosomes for separation, condenses them, and disassembles the nuclear envelope.

What role does the Mitotic Spindle play during Metaphase?

The Mitotic Spindle helps to align the chromosomes at the metaphase plate, ensuring even distribution to the daughter cells.

What happens to sister chromatids during Anaphase?

During Anaphase, sister chromatids are pulled apart to opposite sides of the cell by the spindle fibers.

How does Telophase differ from other stages?

Telophase differs as it is characterized by the reformation of the nuclear envelope around each set of separated chromosomes, signaling the end of mitosis.