Cell Biology
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Introduction to cells
SubtopicIntroduction to cells under Cell Biology for Grade 12 IB.
Preview questions (no answers)
- 1.
Which of these is a fundamental principle of the cell theory?
A.All cells contain a nucleus and membrane-bound organelles
B.Cells are the smallest units of life
C.Cells can arise spontaneously from non-living matter
D.All cells have a cell wall made of cellulose
- 2.
Which of the following describes the function of 'homeostasis' as a characteristic of all living organisms?
A.The ability to produce offspring either sexually or asexually
B.The chemical reactions that take place within the cell to release energy
C.The permanent increase in size or number of cells
D.The maintenance of a constant internal environment despite external changes
- 3.
A student views a micrograph of a cell with an actual length of . If the image size in the textbook is , what is the magnification used?
A.B.C.D.
Download the worksheet for Cell Biology - Introduction to cells to practice offline. It includes additional chapter-level practice questions.
Ultrastructure of cells
SubtopicUltrastructure of cells under Cell Biology for Grade 12 IB.
Preview questions (no answers)
- 1.
Which organelle is responsible for synthesizing proteins that are intended for secretion outside the cell?
A.Rough endoplasmic reticulum
B.Smooth endoplasmic reticulum
C.Free-floating ribosomes
D.Lysosomes
- 2.
By which process do prokaryotic cells typically divide?
A.Mitosis
B.Meiosis
C.Binary fission
D.Budding
- 3.
Which organelle is primarily responsible for the production of ATP through aerobic respiration?
A.Nucleus
B.Mitochondrion
C.Golgi apparatus
D.Lysosome
Download the worksheet for Cell Biology - Ultrastructure of cells to practice offline. It includes additional chapter-level practice questions.
Membrane structure
SubtopicMembrane structure under Cell Biology for Grade 12 IB.
Preview questions (no answers)
- 1.
What property of phospholipids allows them to spontaneously form a bilayer in water?
A.They are entirely hydrophobic
B.They are entirely hydrophilic
C.They are amphipathic
D.They form covalent bonds with water molecules
- 2.
Which model of membrane structure was proposed by Singer and Nicolson in 1972?
A.The Protein-Lipid Sandwich Model
B.The Unit Membrane Model
C.The Fluid Mosaic Model
D.The Davson-Danielli Model
- 3.
What is the primary function of cholesterol within the plasma membrane of animal cells?
A.To facilitate the active transport of glucose
B.To regulate membrane fluidity and permeability
C.To act as a receptor for peptide hormones
D.To provide structural support for the cell wall
Download the worksheet for Cell Biology - Membrane structure to practice offline. It includes additional chapter-level practice questions.
Membrane transport
SubtopicMembrane transport under Cell Biology for Grade 12 IB.
Preview questions (no answers)
- 1.
What property of the plasma membrane allows it to form vesicles during endocytosis and exocytosis?
A.The presence of cholesterol
B.The rigid structure of membrane proteins
C.The fluidity of the phospholipid bilayer
D.The presence of glycoprotein receptors
- 2.
The diagram below represents a specific type of membrane transport. Based on the direction of movement and the concentration gradient shown, which process is being illustrated?
A.Active transport
B.Simple diffusion
C.Endocytosis
D.Exocytosis
- 3.
Which of the following transport mechanisms requires the hydrolysis of ATP to move substances against their concentration gradient?
A.Osmosis
B.Sodium-potassium pump
C.Movement through channel proteins
D.Simple diffusion through the phospholipid bilayer
Download the worksheet for Cell Biology - Membrane transport to practice offline. It includes additional chapter-level practice questions.
The origin of cells
SubtopicThe origin of cells under Cell Biology for Grade 12 IB.
Preview questions (no answers)
- 1.
What size of ribosomes are found inside mitochondria, supporting the theory that they evolved from prokaryotic cells?
A.B.C.D. - 2.
Which organelles provide evidence for the endosymbiotic theory?
A.Ribosomes and Lysosomes
B.Golgi apparatus and Endoplasmic reticulum
C.Mitochondria and Chloroplasts
D.Nucleus and Vacuoles
- 3.
Which of Louis Pasteur's experimental observations led to the rejection of the theory of spontaneous generation?
A.Broth boiled in a swan-necked flask remained clear unless the neck was broken.
B.Organic molecules formed after applying electrical sparks to a mixture of gases.
C.Mitochondria were found to have their own circular DNA.
D.Cells were observed dividing under a light microscope.
Download the worksheet for Cell Biology - The origin of cells to practice offline. It includes additional chapter-level practice questions.
Preview questions (no answers)
- 1.
A diploid cell in a specific organism contains 24 chromosomes. After this cell undergoes mitosis, how many chromosomes will be present in each of the daughter cells?
A.12
B.24
C.48
D.6
- 2.
Which of the following occurs during cytokinesis in plant cells but NOT in animal cells?
A.The formation of a cleavage furrow
B.The formation of a cell plate
C.The condensation of chromatin into chromosomes
D.The movement of chromosomes to the equator
- 3.
What is the primary function of cyclins in the cell cycle?
A.To catalyze the replication of DNA
B.To provide energy for the formation of the spindle apparatus
C.To control the timing and progression of the cell cycle
D.To hold sister chromatids together at the centromere
Download the worksheet for Cell Biology - Cell division to practice offline. It includes additional chapter-level practice questions.