Online Test — Cell Division and Heredity
45 Questions • 15 min • Chapter MCQ
15:00
Question 1 of 45
The process by which one cell divides to form new cells is called:
Respiration
Cell division
Digestion
Diffusion
Explanation: Cell division is the process by which a parent cell forms new daughter cells.
Question 2 of 45
Which of these is NOT a main reason for cell division?
Growth
Repair
Reproduction
Breathing
Explanation: Cells divide for growth, repair, and reproduction — not for breathing.
Question 3 of 45
An organism grows mainly by:
Making each cell huge
Increasing the number of cells
Losing cells
Stopping division
Explanation: Growth occurs chiefly by increasing the number of cells through division.
Question 4 of 45
The healing of a cut on the skin is an example of cell division for:
Reproduction
Repair
Photosynthesis
Digestion
Explanation: New cells made by division repair and heal the wound.
Question 5 of 45
In an Amoeba, cell division mainly serves the purpose of:
Reproduction
Excretion
Breathing
Movement
Explanation: In unicellular organisms, division of the cell produces new individuals (reproduction).
Question 6 of 45
The orderly sequence of stages from a cell's formation until it divides is the:
Food chain
Cell cycle
Water cycle
Life span
Explanation: The cell cycle is the ordered series of stages ending in cell division.
Question 7 of 45
The longest part of the cell cycle, during which the cell grows and prepares, is:
M phase
Interphase
Cytokinesis
Anaphase
Explanation: Interphase is the long growth-and-preparation part of the cycle.
Question 8 of 45
DNA is copied (replicated) during which sub-phase of interphase?
G1
S
G2
M
Explanation: DNA replication occurs in the S (synthesis) phase.
Question 9 of 45
The division of the cytoplasm that splits a cell into two is called:
Mitosis
Cytokinesis
Interphase
Synthesis
Explanation: Cytokinesis is the division of the cytoplasm into two daughter cells.
Question 10 of 45
Uncontrolled cell division, caused by loss of cell-cycle control, can lead to:
Cancer
Digestion
Photosynthesis
Respiration
Explanation: When cycle control fails, cells divide uncontrollably, which can cause cancer.
Question 11 of 45
Mitosis produces daughter cells that are:
Half the chromosome number
Genetically identical to the parent
Always different
Without a nucleus
Explanation: Mitosis yields two cells identical to the parent in chromosome number and type.
Question 12 of 45
The correct order of the stages of mitosis is:
Metaphase, prophase, telophase, anaphase
Prophase, metaphase, anaphase, telophase
Anaphase, telophase, prophase, metaphase
Telophase, anaphase, metaphase, prophase
Explanation: The stages run prophase → metaphase → anaphase → telophase.
Question 13 of 45
Chromosomes line up along the middle of the cell during:
Prophase
Metaphase
Anaphase
Telophase
Explanation: In metaphase the chromosomes align along the equator of the cell.
Question 14 of 45
Sister chromatids are pulled apart to opposite poles during:
Prophase
Metaphase
Anaphase
Interphase
Explanation: In anaphase the chromatids separate and move to opposite poles.
Question 15 of 45
Mitosis in the body mainly helps in:
Making gametes
Growth and repair
Reducing chromosome number
Producing variation
Explanation: Mitosis in body cells provides growth, repair, and replacement.
Question 16 of 45
Meiosis is the type of cell division that produces:
Body cells
Gametes (sex cells)
Bone cells
Skin cells
Explanation: Meiosis produces gametes such as sperm and eggs.
Question 17 of 45
The number of daughter cells formed at the end of meiosis is:
Two
Four
Eight
One
Explanation: Meiosis (two divisions, one DNA copy) gives four daughter cells.
Question 18 of 45
A cell with half the normal chromosome number is described as:
Diploid
Haploid
Doubled
Body cell
Explanation: A haploid cell has a single (half) set of chromosomes.
Question 19 of 45
In humans, a gamete (sperm or egg) carries how many chromosomes?
46
23
92
12
Explanation: Meiosis halves the body cell's 46 chromosomes to 23 in each gamete.
Question 20 of 45
The exchange of genetic material between paired chromosomes in meiosis is called:
Replication
Crossing over
Cytokinesis
Pairing only
Explanation: Crossing over swaps pieces between paired chromosomes, creating variation.
Question 21 of 45
Chromosomes are mainly made of:
Fat
DNA (with proteins)
Sugar only
Water
Explanation: Chromosomes are coiled DNA molecules wound with proteins.
Question 22 of 45
The twisted-ladder shape of DNA is called the:
Triangle
Double helix
Square
Spiral fat
Explanation: DNA's two twisted strands form the double helix.
Question 23 of 45
A short section of DNA carrying instructions for one feature is a:
Cell
Gene
Tissue
Organ
Explanation: A gene is a segment of DNA and the unit of heredity.
Question 24 of 45
A human body cell contains how many chromosomes?
23
46
92
12
Explanation: Human body cells have 46 chromosomes (23 pairs).
Question 25 of 45
The 46 human chromosomes are arranged as:
46 pairs
23 pairs
12 pairs
No pairs
Explanation: They form 23 pairs — one of each from each parent.
Question 26 of 45
The passing of features from parents to offspring is called:
Nutrition
Heredity
Respiration
Digestion
Explanation: Heredity is the transfer of characters from parents to offspring.
Question 27 of 45
The "Father of Genetics" is:
Charles Darwin
Gregor Mendel
Louis Pasteur
Robert Hooke
Explanation: Mendel discovered the laws of inheritance and is called the Father of Genetics.
Question 28 of 45
Mendel carried out his famous experiments on:
Maize plants
Garden pea plants
Rose plants
Mango trees
Explanation: Mendel used the garden pea plant for his breeding experiments.
Question 29 of 45
Crossing pure tall × pure short pea plants gave an F1 generation that was:
All short
All tall
Half tall, half short
3 : 1 tall to short
Explanation: All F1 plants were tall, with shortness hidden.
Question 30 of 45
The factors of a trait separate during gamete formation according to the Law of:
Independent Assortment
Segregation
Gravity
Motion
Explanation: The Law of Segregation states paired factors separate into gametes.
Question 31 of 45
A trait that appears even when only one of its factors is present is:
Recessive
Dominant
Hidden
Lost
Explanation: A dominant trait expresses itself with even a single dominant factor.
Question 32 of 45
The genetic make-up of an organism (e.g. TT, Tt, tt) is its:
Phenotype
Genotype
Species
Habitat
Explanation: Genotype refers to the alleles an organism carries.
Question 33 of 45
Which genotype produces a short pea plant (t = short, recessive)?
TT
Tt
tt
All of these
Explanation: Only tt, with no dominant T, gives the recessive short phenotype.
Question 34 of 45
An organism with two identical alleles (e.g. TT or tt) for a trait is:
Heterozygous
Homozygous
Recessive only
Dominant only
Explanation: Identical alleles make the organism homozygous for that trait.
Question 35 of 45
A plant with genotype Tt is tall because:
t hides T
T is dominant over t
both alleles are recessive
it has no alleles
Explanation: The dominant T is expressed, hiding the recessive t.
Question 36 of 45
The sex chromosomes of a human female are:
XY
XX
YY
XO
Explanation: A female has two X chromosomes (XX).
Question 37 of 45
A human male has the sex chromosomes:
XX
XY
YY
XXY
Explanation: A male has one X and one Y chromosome (XY).
Question 38 of 45
The sex of a child is determined by the:
Mother's egg
Father's sperm
Number of autosomes
Size of the egg
Explanation: Sperm carry either X or Y, so the father's sperm decides the sex.
Question 39 of 45
Which of these is a sex-linked trait?
Tallness in pea
Colour blindness
Seed shape
Pod colour
Explanation: Colour blindness is a recessive X-linked (sex-linked) trait.
Question 40 of 45
Haemophilia is a condition in which the blood:
Clots too fast
Does not clot properly
Turns green
Stops flowing
Explanation: In haemophilia the blood does not clot properly, causing prolonged bleeding.
Question 41 of 45
A sudden, permanent change in the DNA or chromosomes is called a:
Mutation
Mitosis
Mineral
Membrane
Explanation: A mutation is a permanent change in the genetic material.
Question 42 of 45
A change in the DNA of a single gene is a:
Chromosomal mutation
Gene mutation
Cell cycle
Phenotype
Explanation: A gene mutation alters the DNA within one gene.
Question 43 of 45
Down syndrome is caused by an extra copy of chromosome number:
23
21
1
46
Explanation: Down syndrome results from three copies of chromosome 21 (47 in total).
Question 44 of 45
Sickle cell anaemia affects the shape and oxygen-carrying ability of:
Bone cells
Red blood cells
Nerve cells
Skin cells
Explanation: A gene mutation makes red blood cells sickle-shaped, carrying less oxygen.
Question 45 of 45
Which of these can cause mutations?
Radiation (X-rays, UV)
Certain chemicals
Copying mistakes in DNA
All of these
Explanation: Chemicals, radiation, and DNA-copying errors can all cause mutations.