biology final chapter 12

What are the checkpoints in the cell cycle?

G1 checkpoint

G2 checkpoint

M checkpoint

G1 checkpoint

checks if the cell is ready for DNA replication.

G2 checkpoint

ensures DNA replication is complete and the cell is ready for mitosis.

M checkpoint

checks that chromosomes are properly attached to the spindle before division.

How does mitosis maintain chromosome number?

each daughter cell receives an identical set of chromosomes

What happens if a cell fails a checkpoint?

It may enter G0 (resting phase) or undergo apoptosis.

What is the role of centrosomes?

Organize the mitotic spindle.

What are kinetochores?

Protein structures on chromatids where spindle fibers attach.

What are sister chromatids?

Identical copies of a chromosome connected by a centromere.

What is the difference between cytokinesis in plant vs animal cells?

Animal cells form a cleavage furrow, plant cells form a cell plate.

What is cytokinesis?

Division of the cytoplasm, forming two separate cells.

What is happening in telophase?

Chromosomes decondense, nuclear envelope reforms, spindle fibers break down

What occurs in anaphase?

Sister chromatids separate and are pulled toward opposite poles.

What is the metaphase plate?

An imaginary plane where chromosomes align during metaphase.

What occurs during prometaphase?

Nuclear envelope fully breaks down, spindle fibers attach to kinetochores.

What happens during prophase?

Chromosomes condense, spindle fibers form, nuclear envelope begins breaking down.

What is the purpose of mitosis?

To produce two genetically identical daughter cells for growth, repair, and asexual reproduction.

What occurs in G2 phase?

Final preparations for mitosis, including production of microtubules.

What happens in G1 phase?

Cell grows, produces proteins, and carries out normal functions.