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Cell Division Vocabulary

Learning Objectives: Cell Division

Cell Division: Why Cells Divide

Success Criteria:

Compare and contrast cell division in prokaryotes and eukaryotes.

🧬 Prokaryotic Cell Division

Main Process: Binary Fission

Organisms: Bacteria and Archaea
DNA Structure: Single, circular DNA molecule
Steps of Binary Fission:
1. DNA Replication: Circular DNA is copied.
2. DNA Segregation: Copies move to opposite ends of the cell.
3. Cytokinesis: The cell membrane pinches inward, dividing the cell.
Result: Two genetically identical daughter cells.
Speed: Fast (can be as quick as 20 minutes under ideal conditions).
No mitotic spindle or nuclear membrane to break down.

🧬 Eukaryotic Cell Division

Main Processes: Mitosis (for growth) and Meiosis (for reproduction)

Organisms: Plants, animals, fungi, protists
DNA Structure: Multiple linear chromosomes within a nucleus
Steps of Mitosis:
1. Prophase: Chromosomes condense, spindle forms, nuclear envelope breaks down.
2. Metaphase: Chromosomes align at the metaphase plate.
3. Anaphase: Sister chromatids separate and move to opposite poles.
4. Telophase: Nuclear membranes reform, chromosomes decondense.
5. Cytokinesis: Cytoplasm divides, forming two identical cells.
Meiosis: Involves two rounds of division, producing four genetically unique gametes (sex cells).
Result: Mitosis → 2 identical cells; Meiosis → 4 genetically different cells

🔍 Key Differences

Feature	Prokaryotes (Binary Fission)	Eukaryotes (Mitosis/Meiosis)
Organisms	Bacteria, Archaea	Animals, plants, fungi, protists
DNA Structure	Circular, no nucleus	Linear, enclosed in nucleus
Complexity	Simple	Complex
Spindle Apparatus	Not present	Present
Nuclear Envelope	Absent	Breaks down and reforms during mitosis
Speed	Fast	Slower
Genetic Variation	Rare (unless mutation)	Occurs in meiosis

✅ Summary

Prokaryotic division (binary fission) is simple and fast, mainly for reproduction.
Eukaryotic division (mitosis/meiosis) is more complex and tightly regulated, supporting growth, repair, and reproduction, with the added potential for genetic variation in meiosis.Describe the life cycle of a cell.

Describe the phases of the cell cycle.
🌀 Overview of the Cell Cycle Phases
1. Interphase (Longest phase – about 90% of the cycle)
This is when the cell grows, performs its functions, and prepares for division. It's subdivided into three parts:
- G₁ phase (Gap 1):
  - Cell grows in size
  - Organelles and proteins are produced
  - Normal cell functions occur
  - Checkpoint: Is the cell ready for DNA replication?
- S phase (Synthesis):
  - DNA is replicated (each chromosome now has two sister chromatids)
- G₂ phase (Gap 2):
  - Cell continues to grow
  - Prepares proteins and organelles needed for mitosis
  - Final checkpoint: Is all DNA copied and error-free?
2. Mitotic Phase (M Phase)
This includes mitosis (nuclear division) and cytokinesis (cytoplasmic division):
Mitosis is broken into 4 main stages:
- Prophase:
  - Chromosomes condense
  - Spindle fibers form
  - Nuclear envelope breaks down
- Metaphase:
  - Chromosomes align at the cell’s equator (metaphase plate)
- Anaphase:
  - Sister chromatids are pulled apart to opposite poles of the cell
- Telophase:
  - Chromosomes decondense
  - Nuclear envelopes re-form around each set of chromosomes
Cytokinesis (often overlaps with telophase):
- Cytoplasm divides, forming two daughter cells
⏰ Optional Phase: G₀ Phase
- Some cells exit the cycle and enter a resting state called G₀ (e.g., nerve or muscle cells).
- These cells do not divide unless reactivated.
Explain why cells replicate their DNA.
🧬 Why DNA Replication Happens
1. Maintain Genetic Continuity
- DNA contains the instructions for building and operating the cell.
- When a cell divides, both new cells need the same complete set of instructions to function properly.
2. Support Growth and Development
- In multicellular organisms, growth happens by increasing the number of cells.
- Each new cell needs DNA to carry out its role in tissues and organs.
3. Repair and Replace Cells
- Cells are constantly being replaced (e.g., skin, blood, gut lining).
- DNA must be replicated so the replacement cells are fully functional.
4. Reproduction (in single-celled organisms)
- For organisms like bacteria, cell division = reproduction.
- Accurate DNA replication ensures the offspring are genetically identical (unless mutations occur).
🔄 When Does DNA Replication Occur?
- During the S phase (Synthesis phase) of interphase in the cell cycle, before the cell enters mitosis.
⚠ What If DNA Isn’t Replicated Correctly?
- Mutations or missing DNA can lead to dysfunctional proteins, cell malfunction, or even disease like cancer.
✅ Summary
Cells replicate their DNA to:
- Pass on genetic information,
- Ensure proper cell function,
- Enable growth, repair, and reproduction.
Explain how cells regulate the cell cycle.
🛑 Key Ways Cells Regulate the Cell Cycle
1. Checkpoints
There are three main checkpoints that act like stoplights:
- G₁ Checkpoint (Restriction Point):
  - Checks for: cell size, nutrients, DNA damage
  - If conditions aren’t right, the cell may enter G₀ (resting state)
- G₂ Checkpoint:
  - Checks for: correct DNA replication, DNA damage
  - Prevents division if DNA has errors
- M Checkpoint (Spindle Checkpoint):
  - During metaphase
  - Checks that all chromosomes are properly attached to spindle fibers
  - Ensures equal chromosome separation
2. Cyclins and CDKs (Cyclin-Dependent Kinases)
- Cyclins: Proteins that rise and fall in concentration throughout the cell cycle.
- CDKs: Enzymes that, when activated by cyclins, push the cell into the next phase of the cycle.
✅ Example: Cyclin D + CDK4 helps the cell move past the G₁ checkpoint.
3. Tumor Suppressor Genes
- These genes produce proteins that slow down the cycle or trigger apoptosis (cell death) if something goes wrong.
- Examples: p53 and Rb proteins
🛡 p53 is known as the "guardian of the genome"—it can stop the cycle to allow for DNA repair or tell the cell to self-destruct if damage is too severe.
4. Growth Factors and External Signals
- Signals from outside the cell (like hormones or contact with other cells) can start or stop division.
- Example: Platelet-derived growth factor (PDGF) triggers cell division in wound healing.
⚠ What Happens When Regulation Fails?
- Uncontrolled cell division ➜ cancer
- Mutations in genes like p53 or overactive CDKs can lead to tumors
✅ Summary
Cells regulate the cycle through:
- Checkpoints (G₁, G₂, M)
- Cyclins/CDKs (internal timing)
- Tumor suppressor genes (safety brakes)
- External signals (environmental cues)

🧬 Definition of Mitosis

Mitosis is nuclear division in somatic (non-reproductive) cells. It ensures that each daughter cell receives an exact copy of the DNA.

🌀 The 5 Stages of Mitosis (PMAT + C)

1. Prophase

Chromatin condenses into visible chromosomes
Each chromosome has two sister chromatids joined at a centromere
The nuclear envelope breaks down
Spindle fibers begin forming from centrioles (in animal cells)

2. Metaphase

Chromosomes align at the metaphase plate (center of the cell)
Spindle fibers attach to centromeres of each chromosome

3. Anaphase

Sister chromatids separate and are pulled toward opposite poles of the cell
Once separated, chromatids are considered individual chromosomes

4. Telophase

Chromosomes arrive at the poles and decondense back into chromatin
Nuclear envelopes re-form around the two new sets of DNA
The spindle breaks down

5. Cytokinesis (often overlaps with telophase)

The cytoplasm divides
Animal cells: A cleavage furrow forms and pinches the cell in two
Plant cells: A cell plate forms between the new nuclei, becoming a cell wall

📊 Mitosis Model – Simple Chart

Stage	Key Events
Prophase	Chromosomes condense, spindle forms, nuclear envelope dissolves
Metaphase	Chromosomes align at center, spindle fibers attach
Anaphase	Sister chromatids pulled apart to opposite poles
Telophase	Chromosomes decondense, nuclei reform
Cytokinesis	Cytoplasm divides into two identical cells

🔁 End Result:

2 genetically identical diploid daughter cells
Same number of chromosomes as the original cell

Define each step of mitosis.
🧬 1. Prophase
- Chromatin condenses into visible chromosomes.
- Each chromosome consists of two sister chromatids joined at the centromere.
- The nuclear envelope breaks down.
- Spindle fibers begin forming from the centrosomes (with centrioles in animal cells), which move to opposite poles.
🧲 2. Metaphase
- Chromosomes line up along the metaphase plate (the cell’s equator).
- Spindle fibers attach to the kinetochores at the centromeres of each chromosome.
- This alignment ensures equal division of genetic material.
🪢 3. Anaphase
- Sister chromatids separate at the centromere.
- Each chromatid is now an individual chromosome.
- The chromosomes are pulled to opposite poles of the cell by shortening spindle fibers.
🌀 4. Telophase
- Chromosomes reach opposite poles and begin to decondense back into chromatin.
- Nuclear envelopes re-form around each set of chromosomes.
- Spindle fibers break down.
- The cell now has two separate nuclei.
✂ (Bonus) 5. Cytokinesis (not part of mitosis itself but usually follows it)
- Cytoplasm divides, forming two daughter cells.
  - In animal cells: A cleavage furrow pinches the cell in two.
  - In plant cells: A cell plate forms between the new nuclei, eventually becoming the new cell wall.
✅ Summary Mnemonic: "PMAT"
- P – Prophase: Prepare chromosomes
- M – Metaphase: Middle alignment
- A – Anaphase: Apart (chromatids split)
- T – Telophase: Two nuclei form
Describe why cancerous cells divide faster than other cells.
🔁 1. Bypassed Cell Cycle Checkpoints
- Healthy cells use checkpoints (like in G₁, G₂, and M phase) to make sure everything is working correctly before dividing.
- Cancer cells bypass or ignore these checkpoints, allowing them to divide even if there's DNA damage or errors.
🔓 2. Mutations in Regulatory Genes
- Cancer often involves mutations in two key types of genes:
  - Proto-oncogenes: Normally promote cell division. When mutated, they become oncogenes, which overstimulate division.
  - Tumor suppressor genes: Normally slow down the cell cycle or trigger apoptosis (cell death) if something’s wrong. When these are mutated (e.g., p53), cells don’t stop dividing.
🚫 3. No Response to "Stop" Signals
- Normal cells stop dividing when they touch other cells (called contact inhibition).
- Cancer cells ignore this, so they pile up and form tumors.
♾ 4. Unlimited Replication Potential
- Many cancer cells activate an enzyme called telomerase, which keeps their chromosomes from shortening.
- This means they don’t age or die like normal cells—they can divide indefinitely.
💉 5. Resistance to Apoptosis
- Cancer cells often avoid programmed cell death, even if they have severe DNA damage.
- This allows damaged cells to keep dividing, spreading mutations further.
✅ Summary
Cancerous cells divide faster because they:
- Ignore checkpoints
- Have mutations in cell cycle regulators
- Don't respond to stop signals
- Avoid cell death
- Can divide endlessly

Describe each step of meiosis.

✨ Meiosis I: The "Reduction" Division

👉 Chromosome number is cut in half.

1. Prophase I

Chromosomes condense.
Homologous chromosomes (one from each parent) pair up.
They exchange DNA in a process called crossing over.
The nuclear envelope breaks down; spindle forms.

2. Metaphase I

Paired homologous chromosomes line up in the middle of the cell.
Spindle fibers attach to each chromosome.

3. Anaphase I

Homologous chromosomes separate and move to opposite sides.
Sister chromatids stay together.

4. Telophase I

Chromosomes gather at the poles.
Nuclear envelopes may reform.
The cell splits into two (cytokinesis).

🟢 Result after Meiosis I:
2 cells with half the number of chromosomes (but still duplicated).

✨ Meiosis II: The "Division" of Chromatids

👉 Similar to mitosis, but starts with haploid cells.

1. Prophase II

Chromosomes condense again.
Spindles form in both cells.

2. Metaphase II

Chromosomes line up in the middle (single file).

3. Anaphase II

Sister chromatids finally separate and move to opposite ends.

4. Telophase II

Chromatids reach the poles.
Nuclear envelopes form.
Each cell splits again (cytokinesis).

🟢 Final Result after Meiosis II:
4 genetically different haploid cells (each with half the chromosomes of the original).

✅ Super Simple Summary:

Phase	What Happens
Prophase I	Chromosomes pair up, crossing over happens
Metaphase I	Pairs line up in the middle
Anaphase I	Pairs are pulled apart
Telophase I	Two new cells form
Prophase II	Chromosomes condense again
Metaphase II	Chromosomes line up single-file
Anaphase II	Sister chromatids are pulled apart
Telophase II	Four unique cells are formed

Compare and contrast mitosis and meiosis.

🧬 Purpose

Mitosis	Meiosis
Growth, repair, and asexual reproduction	Production of sex cells (sperm & egg)
Creates identical cells	Creates genetically unique cells

🔁 Number of Divisions

Mitosis	Meiosis
1 cell division	2 cell divisions (Meiosis I and II)

🔢 Number of Cells Produced

Mitosis	Meiosis
2 daughter cells	4 daughter cells

🧬 Chromosome Number in Daughter Cells

Mitosis	Meiosis
Diploid (2n) — same as parent	Haploid (n) — half of parent

🧬 Genetic Similarity

Mitosis	Meiosis
Genetically identical to parent and each other	Genetically different due to crossing over and independent assortment

🔄 Crossing Over?

Mitosis	Meiosis
❌ No crossing over	✅ Yes — occurs in Prophase I

👥 Involves Homologous Chromosomes?

Mitosis	Meiosis
❌ No pairing of homologous chromosomes	✅ Yes — pairs up in Prophase I

🧾 Quick Comparison Chart

Feature	Mitosis	Meiosis
Purpose	Growth/repair	Sexual reproduction
Divisions	1	2
Cells made	2	4
Chromosome number	Same as original (diploid)	Half of original (haploid)
Genetic variation	None	Yes (crossing over & assortment)
Occurs in	Somatic (body) cells	Gametes (sex cells)

✅ In a Nutshell:

Mitosis = makes clones (2 identical body cells)
Meiosis = makes variety (4 unique sex cells)

Vocabulary

Cell cycle: The series of events that take place in a cell leading to its division and duplication.
Interphase: The stage of the cell cycle where the cell grows and copies its DNA before mitosis or meiosis.
Gap1 (G1): A phase in the cell cycle where the cell grows in size, synthesizes proteins and organelles.
S (DNA synthesis): A phase in the cell cycle where DNA is replicated.
Gap2 (G2): A phase in the cell cycle where the cell continues to grow and prepares for mitosis or meiosis.
Gap0 (G0): A phase in the cell cycle where the cell is not actively dividing or preparing to divide.
Mitosis (M): A type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
Nuclear Division: The division of the nucleus of a cell during mitosis or meiosis.
Prophase: The first stage of mitosis or meiosis, in which the chromosomes become visible as paired chromatids and the nuclear envelope disappears.
Mitotic spindle: A structure formed in the cell during mitosis or meiosis to separate the chromosomes.
Spindle poles: The microtubule organizing centers from which the spindle fibers extend.
Kinetochore: A protein structure on chromatids where the spindle fibers attach during cell division to pull the chromosomes apart.
Metaphase: The second stage of mitosis or meiosis, in which the chromosomes become attached to the spindle fibers and align in the middle of the cell.
Metaphase plate: An imaginary structure in the middle of the cell where the chromosomes align during metaphase.
Anaphase: The stage of mitosis or meiosis when sister chromatids separate and move to opposite poles of the cell.
Telophase: The final stage of mitosis or meiosis, in which the separated chromosomes reach the opposite poles of the dividing cell and the nuclei of the daughter cells form.
Cytokinesis: The cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells.
Daughter Cells: The cells that result from the division of a single parent cell.
DNA: Deoxyribonucleic acid, a molecule that carries the genetic instructions for all living organisms.
Chromosomes: Structures made of DNA and protein that carry genetic information.
Histone: Proteins around which DNA is wound to form a nucleosome.
Nucleosome: A structural unit of a chromosome consisting of a length of DNA coiled around a core of histones.
Centrioles: A minute cylindrical organelle near the nucleus in animal cells, occurring in pairs and involved in the development of spindle fibers in cell division.
Sister Chromatids: Two identical copies of a single chromosome that are connected by a centromere.
Centromere: The region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.
Checkpoints: Control mechanisms in the cell cycle that ensure proper cell division.
Cyclins: A family of proteins that control the progression of cells through the cell cycle by activating cyclin-dependent kinase (CDK) enzymes.
CDKs: (Cyclin-dependent kinases): A family of protein kinases that control the cell cycle progression. They are only active when bound to a cyclin.
Cell cycle arrest: The stopping of the cell cycle, usually in response to DNA damage or other problems.
Cancer: A disease caused by uncontrolled cell division.
Apoptosis: Programmed cell death.
Meiosis I and II: Two successive nuclear divisions in meiosis resulting in four daughter cells.
Homologous Chromosome Pairs: A set of one maternal and one paternal chromosome that pair up with each other inside a cell during meiosis.
Diploid: Containing two complete sets of chromosomes, one from each parent.
Haploid: Having a single set of unpaired chromosomes.

All this in a cram sheet:

Learning Objectives: Cell Division

Cell Division: Why Cells Divide

Prokaryotic Cell Division
- Main Process: Binary Fission
- Organisms: Bacteria and Archaea
- DNA Structure: Single, circular DNA molecule
- Steps of Binary Fission:
1. DNA Replication: Circular DNA is copied.
2. DNA Segregation: Copies move to opposite ends of the cell.
3. Cytokinesis: The cell membrane pinches inward, dividing the cell.
- Result: Two genetically identical daughter cells.
- Speed: Fast (as quick as 20 minutes).
- Spindle: Not present.
Eukaryotic Cell Division
- Main Processes: Mitosis (growth), Meiosis (reproduction)
- Organisms: Plants, animals, fungi, protists
- DNA Structure: Multiple linear chromosomes within a nucleus
- Steps of Mitosis:
1. Prophase: Chromosomes condense, spindle forms, nuclear envelope breaks down.
2. Metaphase: Chromosomes align at the metaphase plate.
3. Anaphase: Sister chromatids separate to opposite poles.
4. Telophase: Nuclear membranes reform, chromosomes decondense.
5. Cytokinesis: Cytoplasm divides.
- Result: Mitosis → 2 identical cells; Meiosis → 4 genetically different cells.

Key Differences

Feature	Prokaryotes (Binary Fission)	Eukaryotes (Mitosis/Meiosis)
Organisms	Bacteria, Archaea	Animals, plants, fungi, protists
DNA Structure	Circular, no nucleus	Linear, enclosed in nucleus
Complexity	Simple	Complex
Speed	Fast	Slower
Genetic Variation	Rare	Occurs in meiosis

Summary:

Prokaryotic division is simple and fast, mainly for reproduction.
Eukaryotic division is complex and tightly regulated, supporting growth, repair, and reproduction.

Overview of the Cell Cycle Phases

Interphase (90% of the cycle)
- G₁ phase: Cell grows, produces organelles/proteins, checkpoint for readiness for DNA replication.
- S phase: DNA is replicated.
- G₂ phase: Continues to grow, prepares for mitosis, final checkpoint.
Mitotic Phase (M Phase)
- Includes Mitosis (nuclear division) and Cytokinesis (cytoplasmic division).
- Cytokinesis: Cytoplasm divides.

Why DNA Replication Happens

Maintain Genetic Continuity: Ensure both cells have full set of instructions for function.
Support Growth and Development: New cells need DNA to function in tissues/organs.
Repair and Replace Cells: DNA replication needed for replacement cells.
Reproduction (in single-celled organisms): Accurate replication ensures identical offspring.

Key Ways Cells Regulate the Cell Cycle

Checkpoints: G₁, G₂, and M checkpoints like stoplights.
Cyclins and CDKs: Proteins and enzymes that control progression through the cell cycle.
Tumor Suppressor Genes: Slow the cycle or induce apoptosis if issues arise.
Growth Factors and External Signals: External cues can trigger or inhibit division.

Definition of Mitosis

Mitosis is nuclear division in somatic cells, ensuring each daughter cell receives an exact copy of DNA.

The 5 Stages of Mitosis (PMAT + C)

Prophase
Metaphase
Anaphase
Telophase
Cytokinesis

Why Cancerous Cells Divide Faster

Bypassed cell cycle checkpoints.
Mutations in regulatory genes (proto-oncogenes, tumor suppressor genes).
Ignore “stop” signals, pile up, and form tumors.
Activate telomerase for unlimited division.
Resistance to apoptosis.

Describe Each Step of Meiosis

Meiosis I: Reduction Division

Prophase I: Cross-over occurs.
Metaphase I: Pairs line up in center.
Anaphase I: Homologous chromosomes are pulled apart.
Telophase I: Two new cells form.
Meiosis II: Division of Chromatids
Prophase II: Chromosomes condense.
Metaphase II: Align single-file.
Anaphase II: Sister chromatids are pulled apart.
Telophase II: Four unique cells formed.

Comparison of Mitosis and Meiosis

Purpose: Mitosis (growth/repair) vs. Meiosis (sexual reproduction).
Number of Divisions: 1 vs. 2.
Cells Produced: 2 vs. 4.
Chromosome Number: Same as original (diploid) vs. half of original (haploid).
Genetic Variation: None vs. Yes (crossing over & assortment).

Vocabulary

Cell cycle: The series of events that take place in a cell leading to its division and duplication.
Interphase: The stage of the cell cycle where the cell grows and copies its DNA before mitosis or meiosis.
Gap 1 (G1): A phase in the cell cycle where the cell grows in size, synthesizes proteins and organelles.
S (DNA synthesis): A phase in the cell cycle where DNA is replicated.
Gap 2 (G2): A phase in the cell cycle where the cell continues to grow and prepares for mitosis or meiosis.
Gap 0 (G0): A phase in the cell cycle where the cell is not actively dividing or preparing to divide.
Mitosis (M): A type of cell division that results in two daughter cells each having the same number and kind of chromosomes as the parent nucleus, typical of ordinary tissue growth.
Nuclear Division: The division of the nucleus of a cell during mitosis or meiosis.
Prophase: The first stage of mitosis or meiosis in which the chromosomes become visible as paired chromatids and the nuclear envelope disappears.
Mitotic spindle: A structure formed in the cell during mitosis or meiosis to separate the chromosomes.
Spindle poles: The microtubule organizing centers from which the spindle fibers extend.
Kinetochore: A protein structure on chromatids where the spindle fibers attach during cell division to pull the chromosomes apart.
Metaphase: The second stage of mitosis or meiosis in which the chromosomes become attached to the spindle fibers and align in the middle of the cell.
Metaphase plate: An imaginary structure in the middle of the cell where the chromosomes align during metaphase.
Anaphase: The stage of mitosis or meiosis when sister chromatids separate and move to opposite poles of the cell.
Telophase: The final stage of mitosis or meiosis in which the separated chromosomes reach the opposite poles of the dividing cell and the nuclei of the daughter cells form.
Cytokinesis: The cytoplasmic division of a cell at the end of mitosis or meiosis, bringing about the separation into two daughter cells.
Daughter Cells: The cells that result from the division of a single parent cell.
DNA: Deoxyribonucleic acid, a molecule that carries the genetic instructions for all living organisms.
Chromosomes: Structures made of DNA and protein that carry genetic information.
Histone: Proteins around which DNA is wound to form a nucleosome.
Nucleosome: A structural unit of a chromosome consisting of a length of DNA coiled around a core of histones.
Centrioles: A minute cylindrical organelle near the nucleus in animal cells occurring in pairs and involved in the development of spindle fibers during cell division.
Sister Chromatids: Two identical copies of a single chromosome that are connected by a centromere.
Centromere: The region of a chromosome to which the microtubules of the spindle attach, via the kinetochore, during cell division.
Checkpoints: Control mechanisms in the cell cycle that ensure proper cell division.
Cyclins: A family of proteins that control the progression of cells through the cell cycle by activating cyclin-dependent kinase (CDK) enzymes.
CDKs: (Cyclin-dependent kinases): A family of protein kinases that control the cell cycle progression, active only when bound to a cyclin.
Cell cycle arrest: The stopping of the cell cycle, usually in response to DNA damage or other problems.
Cancer: A disease caused by uncontrolled cell division.
Apoptosis: Programmed cell death.
Meiosis I and II: Two successive nuclear divisions in meiosis resulting in four daughter cells.
Homologous Chromosome Pairs: A set of one maternal and one paternal chromosome that pair up within a cell during meiosis.
Diploid: Containing two complete sets of chromosomes, one from each parent.
Haploid: Having a single set of unpaired chromosomes.