Chapter 02
Cells, Tissues & Cytology
Cell organelles, function-to-organelle mapping. Mitochondria is the most-tested organelle.
Practice MCQs · FPSC Pattern
Commit to a choice before opening the explanation. Surface familiarity is the #1 reason candidates fail in the exam hall.
- Q1
The 'powerhouse of the cell' — responsible for producing ATP energy — is the:
- A.Ribosome
- B.Nucleus
- C.Golgi apparatus
- D.Mitochondria
Show explanation
Mitochondria carry out cellular respiration → ATP production.
MPT 2022 & 2024
Full Chapter Notes
Source · FPSC Trap Decoder · CSS MPT Smart Notes (2026 Edition)
2.1 Context
| Indicator | Value |
|---|---|
| MPT Weightage | 4–6 Marks |
| Difficulty Level | Medium |
| Confirmed Past Papers | 2022 · 2023 · 2024 · 2025 |
Trend Alert. FPSC tests Cytology as a definition question (2024 repeat), Mitochondria as the Powerhouse (2023 repeat), Robert Hooke vs Robert Brown discovery timeline, and Plant vs Animal cell differences. The Mitosis vs Meiosis distinction is a consistent trap across 2022–2025.
2.2 High-Yield Fact Snapshot
| FPSC-Tested Fact | Correct Answer | Year Tested |
|---|---|---|
| Cytology is the study of | Cells (structure and function) | 2024 — Repeated |
| Powerhouse of the cell | Mitochondria | 2023 — Repeated |
| Who discovered the cell? | Robert Hooke (1665) | 2022 |
| Who discovered the nucleus? | Robert Brown (1831) | 2022 — Repeated |
| Cell wall in plants is made of | Cellulose | 2025 |
| Mitosis produces | 2 genetically identical daughter cells | 2024 — Repeated |
| Meiosis produces | 4 haploid cells (half chromosomes) | 2025 |
| Protein synthesis occurs at | Ribosomes | 2024 |
2.3 Cellular Organelle Matrix
| Organelle | Nickname | Function | FPSC Strategic Fact |
|---|---|---|---|
| Mitochondria | Powerhouse | Produces ATP via cellular respiration | Contains its own DNA — most tested organelle |
| Ribosomes | Protein Factory | Translates mRNA into proteins | Found in both prokaryotes and eukaryotes; smallest organelle |
| Nucleus | Command Centre | Contains DNA; controls cell growth | First discovered by Robert Brown (1831) |
| Cell Membrane | Security Gate | Semi-permeable; controls entry/exit | Made of phospholipid bilayer |
| Lysosomes | Suicide Bags | Digest waste and old cell parts | Contain digestive enzymes; involved in apoptosis |
| Chloroplast | Solar Panel | Photosynthesis — converts light to glucose | Found ONLY in plant cells; contains chlorophyll |
| Golgi Apparatus | Post Office | Packages and ships proteins | Receives from Ribosomes; sends to cell membrane |
| Vacuole | Storage Tank | Stores water, salts, nutrients | Large central vacuole in plants; multiple small in animals |
2.4 Discovery Timeline — Hooke vs Brown
| Year | Scientist | Discovery | FPSC Mnemonic |
|---|---|---|---|
| 1665 | Robert Hooke | The Cell — saw empty 'rooms' in cork | Hooke = Hull (the outer shell) |
| 1831 | Robert Brown | The Nucleus — found the inner 'nut' | Brown = Brain (the inner core) |
| 1838–39 | Schleiden & Schwann | Cell Theory — all life is made of cells | S+S = Scientists of the Cell Theory |
FPSC Nucleus Trap. 'Who discovered the cell?' → Robert Hooke. 'Who discovered the nucleus?' → Robert Brown. FPSC often asks the second question and relies on candidates confusing it with the first. Hooke saw the outer walls of dead cork cells in 1665 — he never saw a nucleus. Brown used a better microscope in 1831 to find the inner core in living orchid cells.
2.5 Plant vs Animal Cells — Top-Tier Yield
| Feature | Plant Cell | Animal Cell | Logic |
|---|---|---|---|
| Cell Wall | Present (Cellulose) | Absent | Gives plants structural rigidity — trees stand without skeleton |
| Vacuole | One large central vacuole | Many small vacuoles | Large vacuole maintains water pressure (turgor) |
| Chloroplast | Present (for photosynthesis) | Absent | Plants make food; animals eat it |
| Centrioles | Absent | Present | Centrioles assist in animal cell division |
| Shape | Fixed, rigid | Flexible, irregular | Cell wall = fixed; no wall = flexible |
2.6 Cell Division — Mitosis vs Meiosis
| Feature | Mitosis | Meiosis |
|---|---|---|
| Purpose | Growth and Repair | Sexual Reproduction |
| Divisions | One | Two (successive) |
| Daughter Cells | 2 identical cells | 4 haploid cells |
| Chromosomes | Stays 46 → 46 | Halved: 46 → 23 |
| Genetic Identity | Identical to parent | Not identical (variation) |
| Location | Body (Somatic) cells | Gonads (Testes / Ovaries) |
If sperm (46) + egg (46) = 92 chromosomes in the offspring, within one generation chromosome counts would double and become lethal. Meiosis halves the count to 23 in each sex cell so that fertilization restores the normal 46.
2.7 Battle Card — 5-Minute Revision
| Fact | Answer |
|---|---|
| Cytology is the study of | Cells |
| Powerhouse of the Cell | Mitochondria (ATP production) |
| Protein Synthesis Site | Ribosomes |
| Suicide Bags | Lysosomes |
| Solar Panel of the Cell | Chloroplast |
| Discovered the Cell (1665) | Robert Hooke |
| Discovered the Nucleus (1831) | Robert Brown |
| Cell Theory Proposers | Schleiden and Schwann |
| Mitosis | 2 identical cells — Growth and Repair |
| Meiosis | 4 haploid cells — Reproduction |
| Plant Cell Wall Material | Cellulose |
| Organelle ONLY in Plants | Chloroplast (and large central Vacuole) |
| Organelle ONLY in Animals | Centrioles |
| Chromosomes in Sperm/Egg | 23 (Haploid) |
| Chromosomes in Body Cells | 46 (Diploid) |
2.8 Practice MCQs — FPSC Level
Part A — Basic Recall
Direct recall of confirmed FPSC facts (Q1–Q4).
The organelle known as the 'Powerhouse of the Cell' is the:
Show explanation
Mitochondria perform cellular respiration, converting glucose + oxygen into ATP. Muscles, liver, and brain cells have the most mitochondria due to high energy demand.
MPT 2023 — Repeated
The cell nucleus was first discovered in 1831 by:
Show explanation
Robert Brown (1831) used advanced lenses to find the nucleus in orchid cells. Robert Hooke (1665) saw only the outer cell walls of dead cork — he never saw the nucleus.
MPT 2022 — High-frequency trap
Protein synthesis in the cell occurs primarily at the:
Show explanation
Ribosomes translate mRNA into protein chains. They are found on the Rough Endoplasmic Reticulum and free in cytoplasm. The Golgi apparatus packages proteins after ribosomes make them.
MPT 2024
Cytology is specifically defined as the study of:
Show explanation
Cytology (from Greek 'kytos' = hollow vessel/cell) studies cell structure and function. Histology = tissues. Physiology = body functions. This appeared directly in MPT 2024.
MPT 2024 — Repeated
Part B — Trap-Based
Plant vs animal cell confusion and vocabulary traps (Q5–Q8).
Which of the following organelles is found ONLY in plant cells?
Show explanation
Chloroplasts are the site of photosynthesis and are found exclusively in plant cells. Cell membrane, mitochondria, and ribosomes are present in both plant and animal cells.
Trap: FPSC Elite Trap — Plant vs Animal Cell Confusion
The plant cell wall is primarily composed of:
Show explanation
Cellulose is the structural polysaccharide forming the plant cell wall. Glycogen is animal storage carbohydrate. Humans cannot digest cellulose — it functions as dietary fibre.
MPT 2025
Mitosis results in the formation of:
Show explanation
Mitosis produces 2 genetically IDENTICAL daughter cells with the same chromosome number as the parent (46 → 46). It is used for growth and tissue repair.
MPT 2024
Lysosomes are called 'suicide bags' because they:
Show explanation
Lysosomes contain hydrolytic (digestive) enzymes. They digest old cell parts, foreign bodies, and can trigger programmed cell death (apoptosis) — hence 'suicide bags'.
Trap: FPSC Vocabulary Trap
Part C — Elite Simulation
Multi-fact matching and cause-and-effect logic (Q9–Q12).
Which combination of scientist and discovery is CORRECTLY matched?
Show explanation
Schleiden (plants) and Schwann (animals) jointly proposed Cell Theory. Robert Hooke discovered the cell (not nucleus). Robert Brown discovered the nucleus (not cell).
Trap: Multi-fact matching trap
Consider the following regarding Meiosis: (1) It produces four daughter cells. (2) The daughter cells are genetically identical. (3) It involves two successive divisions. Which are correct?
Show explanation
Statements 1 & 3 are TRUE — Meiosis produces 4 daughter cells through two successive divisions (Meiosis I and II). Statement 2 is FALSE — daughter cells are NOT identical because crossing-over during Meiosis I shuffles DNA, creating genetic variation.
Trap: FPSC Elite Trap — Statement 2 is wrong
If ribosomes in a cell become non-functional, the most direct consequence would be:
Show explanation
Ribosomes are the site of protein synthesis. Without functioning ribosomes, no proteins can be made — this stops enzyme production, structural proteins, and hormones.
Trap: Cause-and-effect logic
During Mitosis, the chromosome count in each daughter cell is:
Show explanation
In Mitosis, chromosome count is MAINTAINED: parent 46 → daughters each get 46. In Meiosis, count is HALVED: 46 → 23. This distinction is the most frequent exam trap.
MPT 2025
Answer Key with Trap Analysis
Cells, Tissues & Cytology (Q1–Q12)
| Q | Correct | Type | Primary Trap | Why Others Fail |
|---|