The Cell Cycle - Bio

What is the G2 Phase in the cell cycle?

The G2 Phase is the second gap where the cell grows, prepares for mitosis, and checks for DNA errors before division.

What happens during mitosis?

Divides the nucleus into two identical nuclei and consists of four stages: Prophase, Metaphase, Anaphase, and Telophase.

What occurs in Prophase?

Chromosomes condense and become visible, the nuclear envelope breaks down, and spindle fibers begin to form.

What is the function of spindle fibers during Metaphase?

move chromosomes to line up in the middle of the cell.

What happens during Anaphase?

Spindle fibers shorten, separating sister chromatids and moving them to opposite ends of the cell.

What occurs in Telophase?

Nuclear membranes reform around each set of chromosomes, and chromosomes begin to uncoil.

What is Cytokinesis?

the division of the cytoplasm, producing two identical daughter cells.

How does cytokinesis differ in animal and plant cells?

In animal cells, the cell membrane pinches inward, while in plant cells, a cell plate forms.

What causes cancer in relation to the cell cycle?

uncontrolled cell division, where cells ignore regulatory signals of the cell cycle.

Why do cells divide?

to reduce surface-area-to-volume problems, ensure DNA can support cell functions, and replace old or damaged cells.

What is the relationship between cell size and surface-area-to-volume ratio?

As a cell increases in size, volume increases faster than surface area, making material exchange less efficient.

What are the two major phases of the cell cycle?

Interphase and Mitosis + Cytokinesis

What are the three stages of Interphase?

G1 Phase (First Gap), S Phase (Synthesis), and G2 Phase (Second Gap).

What occurs during the G1 Phase?

the cell grows and carries out normal functions while organelles duplicate.

What is the significance of the restriction site in the G2 Phase?

serves as a checkpoint to ensure the cell has properly copied its DNA before proceeding to mitosis.

What happens if a cell does not pass the first restriction site?

It will enter a stationary phase for the rest of its life.

What is a tumor?

a mass of cells that can form when cells divide uncontrollably.

What is the role of DNA during cell growth?

must adequately support the cell's functions, and as the cell grows, it places more demands on the DNA.

What is the outcome of cell division?

two identical daughter cells.

What is the importance of the cell cycle?

crucial for growth, development, and maintenance of all living organisms.