Cell Cycle Notes

Cell Cycle Notes

by Kara Simpson

Poll

What happens when a cell reaches its size limit?

• It just keeps growing

• It divides

• It dies

• It explodes

​The Cell Cycle

The Cell Cycle is

• The cycle of a cell's growth and division

• ​Three main stages

  • ​Interphase - longest

  • ​Mitosis

  • ​Cytokinesis - shortest

Multiple Choice

What is the cell cycle?

• The gradual development of something, especially from a simple to a more complex form.
• The study of heredity and the variation of inherited characteristics.
• The branch of biology that deals with the relations of organisms to one another and to their physical surroundings.
• The series of events that take place in a cell leading to its division and duplication of its DNA to produce two daughter cells.

Multiple Choice

Which part of the Cell Cycle takes the longest?

• Interphase
• Mitosis
• Prophase
• Cytokinesis

​Cell Cycle Stages

​Interphase: Growth phase

• ​the cell grows in size, performs normal functions, copies its DNA

• ​Three parts

  • ​G1: ​cell growth

    • ​cell functions normally

  • S​: DNA replication

    • Chromatin is split to allows replication

    • Chromatin is the relaxed from of DNA in the nucleus

      • phase that DNA spends most time in because it allows proteins access to information stored in DNA

  • G2

    • cell prepares for division

    • duplicates organelles​

Multiple Choice

What happens in the first part of Interphase?

• Mitosis
• Cell Growth
• DNA Replication
• Anaphase

Multiple Choice

What does DNA Replication mean?

• DNA is made.
• DNA makes new cells. 
• DNA copies itself.
• DNA starts the cell cycle.

​Cell Cycle Stages

​Mitosis: division of the nucleus

• ​Four phases

  • ​Prophase

  • ​Metaphase

  • ​Anaphase

  • ​Telophase

Multiple Choice

What part of the cell cycle results in the splitting of the new cells?

• Interphase
• Mitosis
• Metaphase
• Cytokinesis

​Cell Cyle Stages

​Cytokinesis

• ​Divison of the cytoplasm

​

Two daughter cells are produced

​

​Start the cycle over again at interphase

Multiple Choice

True or False. 
After a cell goes through cytokinesis, it starts mitosis all over again.

• True
• False

Multiple Choice

True or False.
Mitosis is a continuous process.

• True
• False

Multiple Choice

True or False.
Mitosis is made up of 5 phases.

• True
• False

Phases of Mitosis​

PMAT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!​

​Prophase

• ​The longest phase of mitosis

• ​Chromatin condenses to form chromosomes

• ​Sister chromatids attach together near the center of the chromosomes by a centromere

  • ​Sister chromatids are IDENTICAL copies of DNA

• ​Nuclear membrane disappears

• ​Spindle fibers form

• ​Centrioles migrate to opposite ends of the cell for spindle attachment

• ​Sister chromatids attach to spindle fibers

​Metaphase

• ​Chromosomes are lined up at the center of the cell (equator of the cell)

​Anaphase

• ​Shortest phase of mitosis

• ​The centromere splits and the sister chromatids are pulled by the spindle to opposite ends of the cell

​Telophase

• Last part of mitosis

• ​Chromosomes arrive at opposite ends of cells

• ​Chromosomes unwind

• ​Nuclear membrane reforms

• ​Nucleoli reappear

• ​Spindle apparatus is broken down

​Cytokinesis

• Division of the cytoplasm

​Animal Cells

• ​Microtubules constrict, or pinch, the cytoplasm in half

Plant Cells​

• ​Cell plate forms in between the new nuclei

• ​Cell walss form on either side of the cell plate, dividing the cell into two new daughter cells

​Results in two IDENTICAL daughter cells

Multiple Choice

What phase is this cell in?

• Cytokinesis
• Mitosis
• Prophase
• Metaphase

Multiple Choice

What phase is this cell in?

• Mitosis
• Interphase
• Anaphase
• Telophase

Multiple Choice

What phase is this cell in?

• Mitosis
• Cytokinesis
• Prophase
• Telophase

Multiple Choice

What phase is this cell in?

• Mitosis
• Interphase
• Prophase
• Telophase

Multiple Choice

What part of the cell cycle is this cell in?

• Mitosis
• Interphase
• Telophase
• Cytokinesis

Multiple Choice

BONUS:
How long is the whole cell cycle for most animal cells?

• 2-3 days
• 24 hours
• 2-3 hours
• 23 hours

​Prokaryotic Cell Division

​Binary Fission

1. ​DNA is replicated

2. ​DNA and cytoplasm split

3. ​Two new cells produced