Cell Cycle
What are the three main stages of the cell cycle (not including cytokinesis)?
G₁, S, and G₂
During which phase of mitosis do chromosomes line up in the center of the cell?
Metaphase
How many daughter cells are produced by meiosis?
Four
What is the name of the structure that holds sister chromatids together?
Centromere
Mitosis produces cells for growth. Meiosis produces cells for ________.
reproduction
In which stage of the cell cycle does DNA replication occur?
S phase (Synthesis)
What structure pulls sister chromatids apart during mitosis?
Spindle fibers
Are the daughter cells produced by meiosis haploid or diploid?
Haploid
What is the process of cytoplasm dividing called?
Cytokinesis
Name one way meiosis increases genetic variation.
Crossing over or independent assortment
What is the longest phase of the cell cycle, where the cell grows and performs normal functions?
Interphase
What phase comes immediately after anaphase?
Telophase
During which phase of meiosis does crossing over occur?
Prophase I
What are the threadlike strands of DNA and protein found in the nucleus called?
Chromatid
Compare the chromosome number before and after mitosis.
Remains the same (diploid → diploid)
During which stage do cells perform their normal functions but do not divide?
G₀ phase
What is the purpose of mitosis in multicellular organisms?
Growth, repair, and replacement of cells
What is the main purpose of meiosis?
To produce gametes for sexual reproduction
What do spindle fibers do during cell division?
They attach to chromosomes and pull sister chromatids apart to opposite sides of the cell.
Compare the chromosome number before and after meiosis.
Halved (diploid → haploid)
What happens if a cell bypasses normal checkpoints during the cell cycle?
Uncontrolled division can occur, leading to cancer.
A cell starts mitosis with 20 chromosomes. How many chromosomes will each daughter cell have?
20 (same as the parent cell)
If a species’ body cell has 16 chromosomes, how many chromosomes will its gametes have after meiosis?
8
What is the name of the structure that forms between two new cells during cytokinesis in plant cells?
Cell Plate
Explain why siblings from the same parents do not look exactly alike.
Because of genetic variation from crossing over and independent assortment during meiosis