BIOLOGY 121 ACTUAL EXAM PAPER 2026
FULL QUESTIONS WITH CORRECT
ANSWERS GRADED A+
⩥ bacteriophage (phage).
Answer: A virus that infects bacteria
⩥ Reproduction in a bacteriophage uses two routes:.
Answer: The lytic cycle: Viral DNA replicates using cell's machinery;
this culminates in the death of the host cell
The lysogenic cycle: Viral DNA is inserted in bacterial chromosome;
virus remains dormant for long periods
⩥ AIDS (acquired immunodeficiency syndrome).
Answer: caused by HIV (human immunodeficiency virus)
⩥ HIV.
Answer: retrovirus, with an RNA genome that is converted to DNA;
targets cells of the immune system; spreads by sexual contact or by
sharing blood products
⩥ What does HIV use to reproduce?.
,Answer: To reproduce, HIV uses reverse transcriptase to convert RNA
into DNA; during normal DNA expression the host cell will then make
new viral RNA; HIV essentially "hijacks" the cell's own DNA
expression system
⩥ Protease inhibitors.
Answer: interfere with viral proteases so no more proteins formed
⩥ AZT.
Answer: inhibits reverse transcriptase by mimicking thymine, making
DNA production stop
⩥ Emerging virus.
Answer: one that has rapidly come to the attention of scientists
⩥ Pathogen.
Answer: any agent that causes disease
⩥ Living pathogens....
Answer: such as bacteria, fungi, and protists, can cause diseases
⩥ Non-living pathogens.
Answer: include viruses
, ⩥ Prion.
Answer: an infectious protein, a misshapen version of a normal brain
protein; Prions convert normal brain proteins -> assembling in clusters -
> disrupting normal brain function
⩥ Creutzfeldt-Jakob disease (CJD).
Answer: an uncurable degenerative prion disease of the human brain;
contracted from eating mad-cow infected beef; holes develop in brain ->
sponge-like texture
⩥ Viroids (small, circular RNA molecules).
Answer: do not encode proteins but can replicate in host plant cells by
using the host's own cellular enzymes
⩥ Decomposers.
Answer: break down large molecules and absorb the resulting small
molecules; recycling nutrients back into the environment
⩥ Mushrooms.
Answer: produce spores for reproduction
⩥ Belowground, fungi bodies consist of a ____________ that digests
food..
FULL QUESTIONS WITH CORRECT
ANSWERS GRADED A+
⩥ bacteriophage (phage).
Answer: A virus that infects bacteria
⩥ Reproduction in a bacteriophage uses two routes:.
Answer: The lytic cycle: Viral DNA replicates using cell's machinery;
this culminates in the death of the host cell
The lysogenic cycle: Viral DNA is inserted in bacterial chromosome;
virus remains dormant for long periods
⩥ AIDS (acquired immunodeficiency syndrome).
Answer: caused by HIV (human immunodeficiency virus)
⩥ HIV.
Answer: retrovirus, with an RNA genome that is converted to DNA;
targets cells of the immune system; spreads by sexual contact or by
sharing blood products
⩥ What does HIV use to reproduce?.
,Answer: To reproduce, HIV uses reverse transcriptase to convert RNA
into DNA; during normal DNA expression the host cell will then make
new viral RNA; HIV essentially "hijacks" the cell's own DNA
expression system
⩥ Protease inhibitors.
Answer: interfere with viral proteases so no more proteins formed
⩥ AZT.
Answer: inhibits reverse transcriptase by mimicking thymine, making
DNA production stop
⩥ Emerging virus.
Answer: one that has rapidly come to the attention of scientists
⩥ Pathogen.
Answer: any agent that causes disease
⩥ Living pathogens....
Answer: such as bacteria, fungi, and protists, can cause diseases
⩥ Non-living pathogens.
Answer: include viruses
, ⩥ Prion.
Answer: an infectious protein, a misshapen version of a normal brain
protein; Prions convert normal brain proteins -> assembling in clusters -
> disrupting normal brain function
⩥ Creutzfeldt-Jakob disease (CJD).
Answer: an uncurable degenerative prion disease of the human brain;
contracted from eating mad-cow infected beef; holes develop in brain ->
sponge-like texture
⩥ Viroids (small, circular RNA molecules).
Answer: do not encode proteins but can replicate in host plant cells by
using the host's own cellular enzymes
⩥ Decomposers.
Answer: break down large molecules and absorb the resulting small
molecules; recycling nutrients back into the environment
⩥ Mushrooms.
Answer: produce spores for reproduction
⩥ Belowground, fungi bodies consist of a ____________ that digests
food..
