Cell Biology
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Preview questions (no answers)
- 1.
A cell has a high surface area to volume ratio. How does this affect the cell?
A.It makes transport of materials less efficient
B.It makes transport of materials more efficient
C.It prevents the cell from dividing
D.It causes the cell to lose all its DNA
- 2.
Which part of the microscope is used to sharpen the image under high power?
A.Coarse adjustment knob
B.Fine adjustment knob
C.Stage clips
D.Diaphragm
- 3.
Which of the following is a unicellular organism?
A.Bacterium
B.Oak tree
C.Human
D.Mushroom
- 4.
What are the small, circular DNA molecules found in bacteria called?
A.Chromatin
B.Nucleoids
C.Plasmids
D.Centrosomes
- 5.
Louis Pasteur's experiments with swan-neck flasks provided critical evidence for the theory of biogenesis. Based on the experimental procedure shown in the diagram, what was the primary reason that no microbial growth occurred in the flask with the intact neck?
A.The boiling process removed all oxygen required for the spontaneous generation of cells.
B.The curved neck trapped microbes and dust from the air, preventing them from reaching the broth.
C.The heat transformed the broth into a sterile substance that could no longer support the growth of life.
D.The lack of direct sunlight reaching the broth prevented the spontaneous formation of organelles.
- 6.
Which of these is a unique feature of the structure of Paramecium (a unicellular organism) that allows it to regulate water content?
A.Chloroplasts
B.Contractile vacuoles
C.Flagella
D.Mitochondria
- 7.
Metastasis is a process associated with which medical condition?
A.Viral infection
B.Spread of cancer from a primary tumor to other parts of the body
C.Failure of the sodium-potassium pump
D.Dehydration of plant cells
- 8.
A tissue sample has a high mitotic index. Which conclusion is most supported by this observation?
A.The tissue is undergoing rapid growth or repair
B.The cells in the tissue have very long interphases
C.The tissue is from an elderly organism with slow metabolism
D.The tissue has reached its maximum size and stopped growing
- 9.
What is the primary role of the Golgi apparatus in the cell?
A.ATP production through cellular respiration
B.Processing, packaging, and distribution of proteins and lipids
C.Storage of genetic information
D.Synthesis of proteins on the rough surface
- 10.
Which of the following processes requires the use of ATP?
A.Movement of water through an aquaporin
B.Movement of glucose through a transport protein down its concentration gradient
C.Movement of sodium ions out of a cell against their concentration gradient
D.Movement of carbon dioxide out of a cell
Download the worksheet for Cell Biology - Cell Theory to practice offline. It includes additional chapter-level practice questions.
Preview questions (no answers)
- 1.
How do ribosomes differ from most other organelles like mitochondria or the nucleus?
A.They are much larger
B.They are not surrounded by a membrane
C.They are only found in plant cells
D.They contain their own DNA
- 2.
Which of the following is found in the chloroplasts and used for the process of making food?
A.Thylakoids
B.Cristae
C.Centrioles
D.Lysosomes
- 3.
What is the main component of the cytoplasm?
A.Proteins
B.Water
C.Lipids
D.Carbohydrates
- 4.
Which organelle would be very numerous in a cell that produces a lot of enzymes for secretion?
A.Rough Endoplasmic Reticulum
B.Smooth Endoplasmic Reticulum
C.Centrioles
D.Lysosomes
- 5.
What is the primary function of the transport vesicles produced by the Rough Endoplasmic Reticulum?
A.To carry proteins to the Golgi apparatus for further processing.
B.To digest nutrients within the cytoplasm.
C.To move oxygen into the mitochondria.
D.To anchor the cell to its neighbors.
- 6.
If a plant cell is placed in a hypertonic solution and loses water, which organelle will shrink significantly first?
A.Nucleus
B.Central Vacuole
C.Mitochondrion
D.Chloroplast
- 7.
Which organelle is unique in having its own DNA and the ability to replicate independently of the nucleus?
A.Lysosome
B.Chloroplast
C.Golgi Apparatus
D.Rough ER
- 8.
Which statement correctly describes the function of 'integrins' in the cell membrane?
A.They are enzymes that catalyze the synthesis of ATP
B.They transmit signals between the extracellular matrix and the cytoskeleton
C.They act as channels for the passive diffusion of water
D.They help in the folding of proteins within the Rough ER
- 9.
Which organelle would be most abundant in a cell that requires a high amount of active transport, such as a root hair cell in a plant?
A.Chloroplasts
B.Mitochondria
C.Lysosomes
D.Golgi bodies
- 10.
Which of the following is a key difference between the Rough ER and the Smooth ER, aside from the presence of ribosomes?
A.Rough ER is primarily tubular, whereas Smooth ER consists of flattened sacs
B.Rough ER is continuous with the nucleus, while Smooth ER is always near the plasma membrane
C.Rough ER cisternae are flattened sacs, while Smooth ER is more tubular in structure
D.Rough ER synthesizes lipids, while Smooth ER synthesizes carbohydrates
Download the worksheet for Cell Biology - Cell Organelles to practice offline. It includes additional chapter-level practice questions.
Prokaryotic vs Eukaryotic Cells
SubtopicProkaryotic vs Eukaryotic Cells under Cell Biology for Grade 9 IB.
Preview questions (no answers)
- 1.
What is the name of the theory that suggests mitochondria and chloroplasts evolved from prokaryotic cells?
A.Cell Theory
B.Evolutionary Theory
C.Endosymbiotic Theory
D.Gene Theory
- 2.
In which eukaryotic organelle is light energy converted into chemical energy?
A.Mitochondrion
B.Chloroplast
C.Golgi apparatus
D.Lysosome
- 3.
Which cell type is generally considered more primitive and evolutionary older?
A.Eukaryotic
B.Prokaryotic
C.Multicellular
D.Plant
- 4.
What provides the high surface area for ATP production in mitochondria?
A.The outer membrane
B.The stroma
C.The cristae (inner membrane folds)
D.The nucleolus
- 5.
In terms of evolutionary history, which cell type appeared first on Earth?
A.Eukaryotic cells
B.Prokaryotic cells
C.Both appeared at the same time.
D.Multicellular organisms appeared before prokaryotic cells.
- 6.
Which organelle contains digestive enzymes that break down macromolecules and old organelles in eukaryotes?
A.Peroxisome
B.Lysosome
C.Vacuole
D.Ribosome
- 7.
Which of the following is found in both eukaryotic and prokaryotic cells?
A.Nuclear pores
B.ribosomes
C.RNA and DNA
D.Microtubules
- 8.
What is the primary evolutionary advantage of the linear chromosomes found in eukaryotes over the circular chromosomes in prokaryotes?
A.They allow for a more complex regulation of genes and larger genome sizes.
B.They are much faster to replicate during the cell cycle.
C.They do not require any proteins for structural support.
D.They are less likely to be damaged by UV radiation.
- 9.
A cell has a cell wall, ribosomes, and DNA, but no nucleus. Which of the following structures could it ALSO have?
A.A flagellum made of flagellin.
B.A large central vacuole.
C.A Golgi apparatus.
D.An endoplasmic reticulum.
- 10.
Which of the following is a consequence of the lack of compartmentalization in prokaryotic cells?
A.Metabolic reactions are less efficient as enzymes and substrates are not concentrated.
B.Prokaryotes can grow to much larger sizes than eukaryotes.
C.The cell can maintain different levels in different parts of the cytoplasm.
D.DNA is protected from the hazardous chemical reactions of the cytoplasm.
Download the worksheet for Cell Biology - Prokaryotic vs Eukaryotic Cells to practice offline. It includes additional chapter-level practice questions.
Membrane Transport (Diffusion, Osmosis, Active Transport)
SubtopicMembrane Transport (Diffusion, Osmosis, Active Transport) under Cell Biology for Grade 9 IB.
Preview questions (no answers)
- 1.
A cell contains 5% salt and is placed in a solution with 20% salt. What is the solution relative to the cell?
A.Hypotonic
B.Isotonic
C.Hypertonic
D.Dilute
- 2.
Which organelle produces the ATP required for active transport?
A.Chloroplast
B.Ribosome
C.Mitochondrion
D.Vacuole
- 3.
If a membrane allows water but not sugar to pass, it is:
A.Fully permeable
B.Impermeable
C.Selectively permeable
D.A cell wall
- 4.
What is the driving force behind passive transport?
A.The cell's metabolism
B.Random thermal motion of molecules
C.The nucleus
D.Gravity
- 5.
Which of the following is the best definition of a concentration gradient?
A.The total amount of substance in a volume
B.The difference in concentration of a substance between two areas
C.The speed at which molecules move in a solution
D.The pressure exerted by water against a cell membrane
- 6.
Which process is used by white blood cells to engulf bacteria?
A.Facilitated diffusion
B.Active transport
C.Endocytosis
D.Osmosis
- 7.
Which of these describes a hypotonic solution relative to a cell?
A.A solution with a higher solute concentration than the cell
B.A solution with the same solute concentration as the cell
C.A solution with a lower solute concentration than the cell
D.A solution that contains no water
- 8.
Which statement correctly describes 'osmotic pressure'?
A.The pressure required to prevent the net movement of pure water into a solution.
B.The pressure exerted by the cell wall on the cytoplasm during plasmolysis.
C.The force that pulls salt into a cell through a protein channel.
D.The energy produced by the movement of water molecules.
- 9.
What characterizes 'coupled transport' or 'secondary active transport'?
A.One substance moves down its gradient to provide energy for another to move against its gradient.
B.Two substances move in the same direction using two different ATP molecules.
C.A single protein channel allows both water and ions to pass simultaneously.
D.The cell membrane folds inward to capture two different types of particles.
- 10.
The movement of water across a semi-permeable membrane is driven by the difference in:
A.Total gas pressure
B.Water potential
C.Protein concentration
D.Membrane thickness
Download the worksheet for Cell Biology - Membrane Transport (Diffusion, Osmosis, Active Transport) to practice offline. It includes additional chapter-level practice questions.
Plant vs Animal Cells
SubtopicPlant vs Animal Cells under Cell Biology for Grade 9 IB.
Preview questions (no answers)
- 1.
Why do plant cells have a fixed, rectangular shape?
A.Because they have a cell membrane
B.Because they have a cell wall
C.Because they have mitochondria
D.Because they lack a nucleus
- 2.
Where is the DNA located in a prokaryotic cell?
A.Inside the nucleus
B.Inside the mitochondria
C.Floating in the cytoplasm (nucleoid region)
D.Inside the chloroplast
- 3.
What is the function of the flagellum in some animal cells (like sperm cells)?
A.Movement
B.Digestion
C.Protein synthesis
D.Energy storage
- 4.
Which organelle is responsible for maintaining the shape of an animal cell from the inside?
A.Cell Wall
B.Cytoskeleton
C.Chloroplast
D.Large Vacuole
- 5.
Which of the following structures is most likely to be found in a leaf cell but NOT in a root cell of the same plant?
A.Cell wall
B.Nucleus
C.Chloroplast
D.Mitochondrion
- 6.
Which of the following is an example of an organelle that is NOT membrane-bound?
A.Ribosome
B.Mitochondrion
C.Lysosome
D.Chloroplast
- 7.
The double membrane that surrounds the nucleus is called the:
A.Nuclear lamina
B.Nuclear envelope
C.Plasma membrane
D.Nucleoplasm
- 8.
Intermediate filaments, a component of the cytoskeleton, are best known for which function in animal cells?
A.Guiding the movement of chromosomes during mitosis.
B.Providing permanent structural support and maintaining cell shape by bearing tension.
C.Creating the 'beating' motion of cilia.
D.Synthesizing the extracellular matrix.
- 9.
What is the function of the thylakoid membrane within the chloroplast?
A.It is the site of the Calvin Cycle.
B.It contains the chlorophyll and proteins necessary for the light-dependent reactions of photosynthesis.
C.It regulates the movement of water into the chloroplast.
D.It stores the glucose produced during the day.
- 10.
Contrast the functions of the Rough ER and the Smooth ER. Which of the following is correct?
A.Rough ER: Lipid synthesis; Smooth ER: Protein synthesis.
B.Rough ER: Protein synthesis and modification; Smooth ER: Lipid synthesis and detoxification.
C.Rough ER: Found only in plants; Smooth ER: Found only in animals.
D.Rough ER: production; Smooth ER: replication.
Download the worksheet for Cell Biology - Plant vs Animal Cells to practice offline. It includes additional chapter-level practice questions.
Preview questions (no answers)
- 1.
What is a group of specialized cells of the same type working together called?
A.An organ
B.A tissue
C.An organ system
D.An organism
- 2.
Which of these cells is found on the surface of the skin to provide a barrier?
A.Nerve cell
B.Epithelial cell
C.Muscle cell
D.Red blood cell
- 3.
Which feature of a muscle cell allows it to pull on bones?
A.Its ability to shorten (contract)
B.Its ability to carry oxygen
C.Its ability to send electrical signals
D.Its ability to produce seeds
- 4.
What is the main function of a white blood cell?
A.To transport carbon dioxide
B.To protect the body against pathogens
C.To carry electrical impulses
D.To store fat
- 5.
Which plant cell type is responsible for producing the waxy cuticle on the leaf surface?
A.Guard cells
B.Palisade mesophyll
C.Epidermal cells
D.Spongy mesophyll
- 6.
Which of the following is a characteristic of cardiac muscle cells?
A.They are under voluntary control
B.They do not contain mitochondria
C.They are branched and interconnected
D.They are only found in the lungs
- 7.
Why is the cell membrane of an egg cell specialized to change immediately after fertilization?
A.To allow more sperm to enter
B.To prevent any further sperm from entering (polyspermy)
C.To start the process of meiosis
D.To expel the nucleus
- 8.
What happens to the surface area to volume ratio () of a cell as it differentiates from a small stem cell into a large, specialized muscle fiber?
A.The ratio increases, making the cell more efficient at diffusion.
B.The ratio decreases, potentially limiting the rate of diffusion.
C.The ratio remains constant because the shape changes to compensate.
D.The ratio is not relevant to the function of specialized cells.
- 9.
How does the specialization of the xylem vessel differ from that of a tracheid?
A.Tracheids are living cells, whereas xylem vessels are dead.
B.Xylem vessels have perforated end walls or are completely open, while tracheids have pits but closed ends.
C.Only xylem vessels contain lignin in their cell walls.
D.Tracheids transport sugars, while xylem vessels transport water.
- 10.
Egg cells contain a large amount of 'yolk' or cytoplasm. What is the evolutionary benefit of this specialization?
A.It makes the egg larger so sperm can find it more easily.
B.It provides the necessary nutrients for the early stages of embryonic development.
C.It contains the enzymes needed to digest the sperm's flagellum.
D.It protects the DNA from ultraviolet radiation.
Download the worksheet for Cell Biology - Specialized Cells to practice offline. It includes additional chapter-level practice questions.
Theory of Spontaneous Generation
SubtopicTheory of Spontaneous Generation under Cell Biology for Grade 9 IB.
Preview questions (no answers)
- 1.
Which of these scientists worked EARLIEST in history?
A.Louis Pasteur
B.Francesco Redi
C.Lazzaro Spallanzani
D.Rudolf Virchow
- 2.
What was the 'vital force' that people believed was in the air?
A.Oxygen
B.Nitrogen
C.A mysterious energy needed to create life from non-life.
D.Wind power.
- 3.
If you leave a piece of bread on the counter and mold grows, where did the mold come from?
A.It was created from the wheat in the bread.
B.It grew from spores that were already in the air or on the bread.
C.The sunlight turned the bread into mold.
D.It was created by the plastic bag.
- 4.
Which scientist is considered a pioneer of microbiology for his work debunking spontaneous generation?
A.Louis Pasteur
B.Isaac Newton
C.Albert Einstein
D.Marie Curie
- 5.
Which of the following is the most accurate summary of the contribution of Pasteur to the cell theory?
A.He was the first to see cells.
B.He named the 'cell' after looking at cork.
C.He provided experimental evidence that cells do not appear spontaneously.
D.He discovered that plants are made of cells.
- 6.
What was the 'vital' ingredient that Needham claimed was destroyed by Spallanzani’s excessive boiling?
A.Oxygen
B.The vegetative force
C.Nitrogen
D.DNA
- 7.
Before Redi, it was a common belief that bees were produced from the carcasses of dead bulls. This is an example of:
A.Scientific method
B.Biogenesis
C.Spontaneous generation
D.Metamorphosis
- 8.
The 'Principle of Continuity' in biology implies that life is a continuous chain of cell divisions. Which theory is the direct opposite of this principle?
A.The Theory of Evolution.
B.The Theory of Spontaneous Generation.
C.The Germ Theory of Disease.
D.The Theory of Endosymbiosis.
- 9.
Which of these scientists is correctly matched with their contribution to the downfall of spontaneous generation?
A.Redi: Disproved it for maggots; Pasteur: Disproved it for microbes.
B.Needham: Disproved it for bacteria; Spallanzani: Disproved it for mice.
C.Virchow: Disproved it for viruses; Aristotle: Disproved it for fish.
D.Hooke: Disproved it for plants; Leeuwenhoek: Disproved it for sperm.
- 10.
What is the primary reason why 'spontaneous generation' is no longer considered a valid scientific theory?
A.It has been repeatedly falsified by experimental evidence that withstands peer review.
B.It was banned by the international committee of biological standards in 1900.
C.It was found to be mathematically impossible according to the laws of entropy.
D.It only worked when the Earth's atmosphere was composed of pure nitrogen.
Download the worksheet for Cell Biology - Theory of Spontaneous Generation to practice offline. It includes additional chapter-level practice questions.
Preview questions (no answers)
- 1.
What type of cells are produced by meiosis?
A.Somantic cells
B.Diploid cells
C.Haploid gametes
D.Identical clones
- 2.
Why is it important for DNA to replicate before cell division?
A.So the cell can get bigger
B.To ensure each daughter cell gets a full set of genetic instructions
C.To produce more energy for the cell
D.To destroy the old nucleus
- 3.
Which of the following represents the correct sequence of development?
A.Zygote -> Meiosis -> Gamete
B.Gametes -> Fertilization -> Zygote
C.Mitosis -> Gametes -> Zygote
D.Zygote -> Fertilization -> Gametes
- 4.
How many chromosomes are in a human zygote?
A.23
B.46
C.92
D.69
- 5.
Prokaryotic cells, such as bacteria, divide using a process called binary fission as shown in the diagram. Which of the following describes a major difference between binary fission and eukaryotic mitosis?
A.Binary fission requires the dissolution of a nuclear membrane before DNA can replicate.
B.Binary fission involves the exchange of genetic material between two parent cells to increase variation.
C.Mitosis involves the separation of multiple linear chromosomes using a spindle, whereas binary fission does not.
D.Binary fission results in four daughter cells, whereas mitosis results in two.
- 6.
If a cell fails a checkpoint in the cell cycle, it may enter a programmed cell death process called:
A.Mitosis
B.Apoptosis
C.Cytokinesis
D.Interphase
- 7.
Which of the following best describes 'sister chromatids'?
A.Two different chromosomes from different parents
B.Identical copies of a single chromosome joined at a centromere
C.The two nuclei formed after mitosis
D.Chromosomes that do not pair up during meiosis
- 8.
How many times does the DNA replicate in a cell that undergoes Meiosis?
A.Zero
B.Once, before Meiosis I
C.Twice, once before Meiosis I and once before Meiosis II
D.Four times, once for each gamete
- 9.
What would happen if the spindle fibers failed to attach to one side of a chromosome during Mitosis?
A.The cell would divide normally into two identical cells
B.One daughter cell would have an extra chromosome and the other would be missing one
C.The cell would immediately stop the process and reverse to
D.The DNA would be replicated again to compensate
- 10.
In which stage of Prophase I do homologous chromosomes finish pairing and start crossing over?
A.Leptotene
B.Zygotene
C.Pachytene
D.Diplotene
Download the worksheet for Cell Biology - Cell Division to practice offline. It includes additional chapter-level practice questions.