Genetics and Evolution
Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.
Principles of Inheritance and Variation
SubtopicPrinciples of Inheritance and Variation under Genetics and Evolution for Grade 12 ICSE.
Preview questions (no answers)
- 1.
Mendel's Law of Independent Assortment is applicable to genes located on:
A.The same chromosome
B.Non-homologous chromosomes
C.Sex chromosomes only
D.The same locus
- 2.
Mutation resulting from the deletion or insertion of base pairs in DNA is called:
A.Point mutation
B.Frame-shift mutation
C.Silent mutation
D.Missense mutation
- 3.
In birds, which gamete determines the sex of the offspring?
A.Sperm
B.Egg
C.Both sperm and egg
D.Neither sperm nor egg
- 4.
A cross between a red-flowered pea plant and a white-flowered pea plant results in all red-flowered plants in the generation. This demonstrates the:
A.Law of Segregation
B.Law of Dominance
C.Law of Independent Assortment
D.Incomplete Dominance
- 5.
Mendel’s Law of Independent Assortment is based on his observations of:
A.Monohybrid crosses
B.Dihybrid crosses
C.Test crosses
D.Back crosses
- 6.
If two parents are carriers for Thalassemia (autosomal recessive), what is the probability that their child will be affected?
A.25%
B.50%
C.75%
D.100%
- 7.
The distance between genes is measured in units called centimorgans (cM). What does 1 cM represent?
A.1% linkage
B.1% recombination frequency
C.10% recombination frequency
D.100% crossing over
- 8.
Which of the following chemical mutagens acts as a base analog to Thymine and can cause transitions?
A.5-Bromouracil
B.Nitrous acid
C.Proflavin
D.Ethyl methanesulfonate (EMS)
- 9.
In human genetics, a 'Consanguineous marriage' in a pedigree is represented by:
A.Double horizontal lines between a male and a female symbol
B.A horizontal line with a diagonal slash
C.A shaded square connected to a shaded circle
D.A diamond symbol
- 10.
What is the function of the gene on the human Y-chromosome?
A.It encodes the Testis-Determining Factor (TDF).
B.It regulates the production of sperm in the epididymis.
C.It prevents the inactivation of the X-chromosome in males.
D.It codes for the H-Y antigen.
Download the worksheet for Genetics and Evolution - Principles of Inheritance and Variation to practice offline. It includes additional chapter-level practice questions.
Molecular Basis of Inheritance
SubtopicMolecular Basis of Inheritance under Genetics and Evolution for Grade 12 ICSE.
Preview questions (no answers)
- 1.
The structural gene 'y' in the Lac operon codes for:
A.-galactosidase
B.Permease
C.Transacetylase
D.Repressor protein
- 2.
Which nitrogenous base pairs with Adenine in RNA?
A.Thymine
B.Guanine
C.Cytosine
D.Uracil
- 3.
Which sugar is found in RNA but not in DNA?
A.Glucose
B.Deoxyribose
C.Ribose
D.Lactose
- 4.
According to the Central Dogma, what is the process of converting RNA into Protein?
A.Transcription
B.Replication
C.Translation
D.Transformation
- 5.
Spliceosomes are NOT found in the cells of:
A.Plants
B.Animals
C.Bacteria
D.Fungi
- 6.
The largest known human gene, according to the Human Genome Project, is:
A.Insulin gene
B.Dystrophin
C.Hemoglobin gene
D.Oncogene
- 7.
In the context of the Human Genome Project, 'SNPs' stands for:
A.Single Nucleotide Polymorphisms
B.Small Nuclear Proteins
C.Simple Nucleotide Parts
D.Sequential Nuclear Polyploidy
- 8.
The total number of hydrogen bonds in a DNA fragment of 100 base pairs, where 40% are Cytosine, would be:
A.240
B.260
C.200
D.300
- 9.
In Avery, MacLeod, and McCarty's experiment, the 'transforming principle' was destroyed by which of the following enzymes?
A.Proteases
B.RNases
C.DNases
D.Lipases
- 10.
During the elongation phase of translation, into which site of the ribosome does the incoming aminoacyl-tRNA typically enter?
A.P-site
B.A-site
C.E-site
D.Small subunit binding site
Download the worksheet for Genetics and Evolution - Molecular Basis of Inheritance to practice offline. It includes additional chapter-level practice questions.
Preview questions (no answers)
- 1.
Fossils are generally found in which type of rocks?
A.Igneous rocks
B.Metamorphic rocks
C.Sedimentary rocks
D.Volcanic rocks
- 2.
Which type of natural selection favors the average individuals of a population?
A.Directional selection
B.Stabilizing selection
C.Disruptive selection
D.Artificial selection
- 3.
In the context of evolution, 'Fitness' according to Darwin refers ultimately to:
A.Physical strength
B.Intellectual ability
C.Reproductive fitness
D.Longevity
- 4.
The formation of new species from existing ones is known as:
A.Speciation
B.Mutation
C.Isolation
D.Adaptation
- 5.
Which of the following fossil types is formed when the organic matter of an organism is completely replaced by minerals?
A.Molds
B.Casts
C.Petrifaction
D.Compression
- 6.
In the process of evolution, 'Saltation' refers to:
A.Gradual changes over many generations
B.A single-step large mutation leading to speciation
C.The movement of genes between populations
D.The effect of salt concentration on early cells
- 7.
The presence of 'gill slits' in the embryos of all vertebrates is used as evidence for evolution. Which of the following best explains why these are present?
A.Vertebrates need to breathe through gills in the womb
B.It shows that all vertebrates share a common aquatic ancestor
C.Gill slits are necessary for the development of the heart
D.They are vestigial organs that have no purpose in development
- 8.
Which of the following is a 'Connecting Link' between Annelida and Arthropoda?
A.Peripatus
B.Neopilina
C.Balanoglossus
D.Chimaera
- 9.
The concept of 'reproductive fitness' (Darwinian fitness) is measured by:
A.The number of viable offspring reaching reproductive age
B.The physical strength and speed of an individual
C.The ability of an individual to survive harsh winters
D.The lifespan of an individual compared to others
- 10.
What is the main limitation of Carbon-14 dating in palaeontology?
A.It can only date fossils up to about 50,000 to 70,000 years old
B.It can only be used on volcanic rocks
C.It is inaccurate for organisms that lived in the ocean
D.It requires a very large sample of the fossil to be destroyed
Download the worksheet for Genetics and Evolution - Evolution to practice offline. It includes additional chapter-level practice questions.