CNIH ENTRANCE ACTUAL PAPER 2026
QUESTIONS WITH SOLUTIONS GRADED A+
⩥ Element.
Answer: Pure substance composed of all of the same type of atom - eg.
O2.
⩥ Compound.
Answer: Made up of 2 or more atoms of different elements bonded
together in a fixed ratio - pure substances because they have the same
type of particles - eg. H2O.
⩥ Molecule.
Answer: Formed when atoms join together - could be either an element
or a compound.
⩥ Symbiosis.
Answer: A situation in which two organisms live in close contact and at
least one benefits.
⩥ Mutualism.
Answer: A situation in which two organisms live in close contact and
both benefit.
,⩥ Parasitism.
Answer: A situation in which one organism lives in or on another
organism and feeds on that organism (eg. Lice).
⩥ Commensalism.
Answer: A situation in which two organisms live in close contact; one
benefits and the other is not affected (eg. Ivy growing on tree trunk).
⩥ Invasive species.
Answer: Species introduced by humans into new environments with
unforeseen consequences.
⩥ Monoculture.
Answer: Crops grown in large fields containing a single kind of plant.
⩥ Climate change.
Answer: Large quantities of greenhouse gases produced and emitted that
trap thermal energy in the atmosphere.
⩥ Extirpation.
Answer: Habitat loss and pollution which can lead to the loss of a
species from a particular region - isolated habitat loss.
,⩥ Sustainability.
Answer: How ecosystems support organisms, remain diverse and
productive now, without compromising future generations' use.
⩥ Cytoplasm.
Answer: Jelly like fluid inside cells - surrounds organelles and contains a
'soup' of important chemicals needed for cell processes.
⩥ Vacuole.
Answer: Membrane sacks - store food and water (and in plants, maintain
cell shape).
⩥ Lysosome.
Answer: Vacuole with digestive enzymes - breaks down food and
involved in apoptosis (controlled cell death).
⩥ Cell membrane.
Answer: Membrane filled with proteins and enzymes - control what goes
in and what comes out of the cells, separates cell from external
environment.
⩥ Endoplasmic Reticulum.
, Answer: System of tubes made from membranes - transports proteins
and other material throughout the cell.
⩥ Ribosome.
Answer: Very small structures made of DNA and protein usually found
on ER - make proteins by 'reading' genetic code.
⩥ Golgi body.
Answer: Membrane tubes in a bundle with buds of membrane coming
off - sorts, modifies, packages, and ships proteins.
⩥ Mitochondria.
Answer: Oval-shaped organelle with a double membrane - the
'powerhouse' of the cell; produces energy from food (sugars) - performs
cellular respiration.
⩥ Nuclear Membrane.
Answer: Membrane around the nucleus that is very porous - allows the
genetic code to be communicated with the ribosomes and allows other
materials in and out of the nucleus.
⩥ Nucleus.
Answer: Circular structure with a membrane - holds and protects the
chromatin.
QUESTIONS WITH SOLUTIONS GRADED A+
⩥ Element.
Answer: Pure substance composed of all of the same type of atom - eg.
O2.
⩥ Compound.
Answer: Made up of 2 or more atoms of different elements bonded
together in a fixed ratio - pure substances because they have the same
type of particles - eg. H2O.
⩥ Molecule.
Answer: Formed when atoms join together - could be either an element
or a compound.
⩥ Symbiosis.
Answer: A situation in which two organisms live in close contact and at
least one benefits.
⩥ Mutualism.
Answer: A situation in which two organisms live in close contact and
both benefit.
,⩥ Parasitism.
Answer: A situation in which one organism lives in or on another
organism and feeds on that organism (eg. Lice).
⩥ Commensalism.
Answer: A situation in which two organisms live in close contact; one
benefits and the other is not affected (eg. Ivy growing on tree trunk).
⩥ Invasive species.
Answer: Species introduced by humans into new environments with
unforeseen consequences.
⩥ Monoculture.
Answer: Crops grown in large fields containing a single kind of plant.
⩥ Climate change.
Answer: Large quantities of greenhouse gases produced and emitted that
trap thermal energy in the atmosphere.
⩥ Extirpation.
Answer: Habitat loss and pollution which can lead to the loss of a
species from a particular region - isolated habitat loss.
,⩥ Sustainability.
Answer: How ecosystems support organisms, remain diverse and
productive now, without compromising future generations' use.
⩥ Cytoplasm.
Answer: Jelly like fluid inside cells - surrounds organelles and contains a
'soup' of important chemicals needed for cell processes.
⩥ Vacuole.
Answer: Membrane sacks - store food and water (and in plants, maintain
cell shape).
⩥ Lysosome.
Answer: Vacuole with digestive enzymes - breaks down food and
involved in apoptosis (controlled cell death).
⩥ Cell membrane.
Answer: Membrane filled with proteins and enzymes - control what goes
in and what comes out of the cells, separates cell from external
environment.
⩥ Endoplasmic Reticulum.
, Answer: System of tubes made from membranes - transports proteins
and other material throughout the cell.
⩥ Ribosome.
Answer: Very small structures made of DNA and protein usually found
on ER - make proteins by 'reading' genetic code.
⩥ Golgi body.
Answer: Membrane tubes in a bundle with buds of membrane coming
off - sorts, modifies, packages, and ships proteins.
⩥ Mitochondria.
Answer: Oval-shaped organelle with a double membrane - the
'powerhouse' of the cell; produces energy from food (sugars) - performs
cellular respiration.
⩥ Nuclear Membrane.
Answer: Membrane around the nucleus that is very porous - allows the
genetic code to be communicated with the ribosomes and allows other
materials in and out of the nucleus.
⩥ Nucleus.
Answer: Circular structure with a membrane - holds and protects the
chromatin.
