2nd year Biology Guess Paper 2026 PDF (All Punjab Board)
2nd Year Biology Guess Paper 2026 (Important Questions)
Welcome to www.zahidnotes.com! If you are a 12th-class student preparing for your annual board exams, you know how extensive the biology syllabus can be. To help you secure maximum marks, we have compiled the ultimate 2nd Year Biology Guess Paper 2026.
Below, you will find a chapter-wise breakdown of the most important short and long questions. (Note: Chapter 26 has been skipped as it holds less weight for subjective questions, and long questions have been omitted from certain chapters according to the latest 2026 pairing scheme).
How to pass Biology 2nd year
Chapter 15: Homeostasis
Important Short Questions
Define homeostasis with examples.
What are heat shock proteins?
What is hypertonic and hypotonic environment and what changes occur in a cell in this environment?
Differentiate between osmoconformers and osmoregulators.
Differentiate between active flight and passive flight.
Differentiate between shivering thermogenesis and non-shivering thermogenesis.
Define endotherms, ectotherms, and heterotherms.
Write four adaptations of xerophytes, hydrophytes, and mesophytes.
Differentiate between fibers and sclereids.
Differentiate between afferent and efferent arterioles.
Define lithotripsy.
What is hemodialysis? Give its importance.
What is foramen triosseum? How is it formed?
What is renal failure?
Differentiate between ureotelic and uricotelic animals.
Define anhydrobiosis with an example.
What is hyperoxaluria?
Differentiate between photonasty and thermonasty.
Define phototactic and chemotactic movements with examples.
Important Long Questions
Discuss excretion in plants.
Discuss kidney disorders with treatment.
Discuss the role of the liver as an excretory organ.
Discuss the system of thermoregulation in mammals.
Chapter 16: Support and Movement
Important Short Questions
Differentiate between bone and cartilage.
Name the unpaired facial bones.
Differentiate between apical, lateral, and intercalary meristems.
What is blastoderm? Name its layers.
What is hematoma formation?
How is a callus formed?
What is a synovial joint?
Give the composition of the exoskeleton in molluscs and arthropods.
Differentiate between hyaline and fibrocartilage.
What is sciatica and its causes?
Differentiate between effective and recovery strokes.
What is non-disjunction? Give its effects.
What is rickets? Give its causes and treatment.
Differentiate between tendons and ligaments.
What are the internal factors which affect the process of growth?
What is secondary growth? Give its importance.
What are brachialis and brachioradialis?
Important Long Questions
What is an endoskeleton? Describe bone and cartilage.
Describe the significance of secondary growth in plants. Discuss phases of plant growth.
Give a detailed note on the sliding filament model.
Explain the main parts of the axial skeleton and appendicular skeleton.
Explain different types of joints.
Chapter 17: Nervous Coordination
Important Short Questions
What are effectors? Give their types.
Name the types of innate behavior.
Differentiate between neurula and neurocoel.
Define primary organizer and primary induction.
Draw and label a sensory neuron.
Define reflex arc.
Differentiate between nerves and ganglia.
What is a saltatory impulse?
What are the effects of nicotine on coordination?
What is chlorosis?
What is a hormone? List its types.
Define habituation with an example.
Give functions of the parathyroid gland and adrenal gland.
What is Alzheimer’s disease?
Important Long Questions
The nervous system of Hydra is better developed than that of Planaria. Discuss.
Explain the structure and functions of the human brain with a diagram.
Write a note on the adrenal gland.
How is a nerve impulse produced? Explain its mechanism with a diagram.
Chapter 18: Reproduction
Important Short Questions
Differentiate between sexual and asexual reproduction.
Define parthenocarpy. Give examples.
What is seed dormancy? Give its importance.
What is photoperiodism? Give its effects on plants.
Define vernalization. Write its two advantages.
Define tissue culture and cloning with examples.
Differentiate between identical and fraternal twins.
Differentiate between oviparous and viviparous.
Define menstrual cycle, oestrous cycle, and menopause.
What is diploid parthenogenesis?
What is the structure and function of corpus luteum?
Name STDs with their relative causative agents.
Define apomixis.
Define haploid and diploid parthenogenesis.
What is ovulation?
Important Long Questions
Explain the female menstrual cycle.
Explain the male reproductive system of man.
Compare asexual reproduction with sexual reproduction.
Elaborate on the functions of the placenta during pregnancy.
Chapter 19: Growth and Development
Important Short Questions
Differentiate between growth and development.
Differentiate between apical, lateral, and intercalary meristems.
Write three signs of aging.
Give two causes of abnormal development.
What is blastoderm? Name its layers.
What are the internal factors which affect the process of growth?
What is discoidal cleavage?
Differentiate between neurula and neurocoel.
What is organogenesis?
Define regeneration with an example.
What is a meristem?
What do you know about open growth?
Differentiate between morula and blastula stages in the development of a chick.
What is the basic difference between a chick and an amphibian embryo?
Define correlation.
Define hypoblast and epiblast.
Describe the role of cytoplasm in development.
What is meant by differentiation?
Important Long Questions
Write a note on the development of a chick.
Describe the signs and causes of abnormal development.
Explain internal and external factors of growth.
Explain the phases of growth in plants.
Chapter 20: Chromosomes and DNA
Important Short Questions
Define recombinant DNA. What is the role of lambda phage?
What is an anticodon?
What is a karyotype?
Write 3 major classes of RNA.
What is mutation?
Where does DNA replication start on the DNA molecule?
Define the transformation process.
Define chromosomes and nucleosomes.
Define semi-conservative replication.
Explain sex-limited traits.
What is a phosphodiester linkage?
Write the main components of DNA.
Define point mutation and chromosomal aberration.
What are Okazaki fragments? Give their length.
Differentiate between transcription and translation.
Important Long Questions
Describe DNA as hereditary material in detail.
Explain the work of Meselson and Stahl in DNA study.
What are chromosomes? What do you know about their types?
Explain the Watson and Crick model of DNA.
Chapter 21: Cell Cycle
Important Short Questions
What is non-disjunction? Give its effects.
Define cell cycle. Give its phases.
How does cytokinesis occur in animals and plants?
What is the mitotic apparatus? Give its functions.
Explain homologous and analogous organs.
Give the importance of mitosis/meiosis.
What is metastasis? Write its importance.
Differentiate between apoptosis and necrosis.
Write the symptoms and causes of Down’s syndrome.
What is Turner’s syndrome? Give its causes and features.
Define crossing over.
What is meant by the G0 phase?
How does the prophase of meiosis differ from that of mitosis?
What are chiasmata?
What is interphase? Why is it called the resting phase?
Chapter 22: Variation and Genetics
Important Short Questions
Define euchromatin.
What is cretinism?
Describe gonorrhea.
What is transformation?
What are allele, gene, gene pool, and gene frequency?
What is over-dominance and co-dominance?
What is genetic drift? Genetic code? Fixed alleles?
Name any four animals declared extinct in Pakistan.
Define homozygous and heterozygous alleles.
What is Epistasis? What is Bombay Phenotype? Dominance?
Differentiate between genotype and phenotype.
What is totipotency and a totipotent cell?
What is a true-breeding variety?
What is meant by MODY?
Important Long Questions
Explain epistasis with an example of the Bombay phenotype.
Define and explain Mendel’s Law of Segregation.
What is incomplete dominance? Explain with an example.
Explain the phenomenon of gene linkage regarding linkage groups.
Chapter 23: Biotechnology
Important Short Questions
Define biotechnology. Give its applications.
Differentiate between molecular scissors and molecular vectors.
Give two requirements to produce recombinant DNA.
Explain and give examples of ex vivo and in vivo gene therapies in humans.
What are transgenic plants?
Give three possible ways to get the gene of interest.
Give two goals of the Human Genome Project.
What is a probe? Give its uses.
Define genomic library.
Chapter 24: Evolution
Important Short Questions
How is artificial selection different from natural selection?
State the theory of special creation.
Name any four animals declared extinct in Pakistan.
Define neo-Darwinism / modern synthesis.
Define population genetics.
What are hydrothermal vents? How do they support life?
What are vestigial organs? Name some important vestigial organs of man.
Define fossils. How do they provide evidence of evolution?
What are endangered and threatened species? Give some examples.
What is the Hardy-Weinberg theorem? Give its equation.
Differentiate between homologous and analogous organs.
State the endosymbiont hypothesis.
Important Long Questions
Discuss evolution from prokaryotes to eukaryotes.
Describe the evidence of evolution from various branches of biology like biogeography and fossil study.
Explain Darwin’s theory of natural selection.
Chapter 25: Ecosystem
Important Short Questions
Write down the types of living organisms found in the limnetic zone.
Differentiate between climate and weather.
Define renewable and non-renewable resources.
Define ecosystem, biosphere, and biome.
Differentiate between population and community with examples.
Differentiate between synecology and autecology.
What is predation? Give its significance.
Define parasitism and commensalism.
Define food chain and food web.
Differentiate between habitat and niche.
Differentiate between consumers and decomposers.
Differentiate between hydrosere and xerosere.
Differentiate between primary succession and secondary succession.
Important Long Questions
Write a note on the nitrogen cycle.
Explain the biotic components of an ecosystem.
Explain xerosere succession stages.
Explain the flow of energy in a food chain.
Chapter 27: Man and His Environment
Important Short Questions
Define deforestation and afforestation.
What is the ozone layer? Give its important function in the environment.
Define water pollution and acid rain.
Write a brief note on non-renewable energy resources.
Explain the causes and effects of ozone depletion.
Give the main causes/sources of water pollution.
What is solid waste? Give its importance.
Define greenhouse effect. Give its effects on the environment.
How do trees act as environmental buffers?
Important Long Questions
Describe deforestation and its effects.
Write a note on: a) Ozone depletion b) Greenhouse effect.
Explain the importance of forests/trees.
Briefly explain the causes and effects of air pollution.
Download 2nd Year Biology Guess Paper 2026 PDF
Now the guess paper is over. (Note: Chapter 26 has been skipped because it is not highly important for subjective sections. Moreover, the long questions have been skipped from certain chapters as no long question will come from those chapters according to the pairing scheme).