Which is characteristic of both prokaryotes and viruses?


::indent
- :::tableoptions{col1="hide" col2="hide"}
    | | |
    | :-- | :-- |
    | I. | Contain genetic code  |
    | II. | Rely on host cell for metabolism |
    | III. | Surrounded by cell wall |
    :::

:br

::indent
- A.$\hspace{1em}$ I only

- B.$\hspace{1em}$ I and II 

- C.$\hspace{1em}$ II and III 

- D.$\hspace{1em}$ I, II and III

Viruses, compared to living organisms, are very small. Which other characteristic listed below distinguishes viruses from unicellular living organisms?

:br

::indent
- A.$\hspace{1em}$ Contain genetic material  

- B.$\hspace{1em}$ Contain cytoplasm

- C.$\hspace{1em}$ Lack enzymes

- D.$\hspace{1em}$ Genetic material is surrounded by a capsid

 Bacteriophages and coronaviruses are both viruses that affect living organisms. Which structures are present in both bacteriophages and coronaviruses?


::indent
- :::tableoptions{col1="hide" col2="hide"}
    | | |
    | :-- | :-- |
    | I. | cytoplasm |
    | II. | capsid |
    | III. | genetic material |
    :::

:br

::indent
- A.$\hspace{1em}$ I only

- B.$\hspace{1em}$ I and II only

- C.$\hspace{1em}$ II and III only

- D.$\hspace{1em}$ I, II and III

Which of the rows below shows the correct characteristics of viruses, prokaryotes and eukaryotes?  

:br

:::tableoptions{col1="hide"}
| | Virus | Prokaryote | Eukaryote
| --- | :-: | :-: | :-: |
| A.$\hspace{1em}$ | Genome is DNA or RNA | Genome is DNA only | Genome is DNA only |
| B.$\hspace{1em}$ | Rely on host cell for nutrition | Rely on host cell for nutrition | Does not rely on host cell for nutrition |
| C.$\hspace{1em}$ | Synthesises ATP for energy supply| Synthesises ATP for energy supply | Synthesises ATP for energy supply |
| D.$\hspace{1em}$ | Capsid present | Capsid present | Capsid present|
:::

\[Maximum mark: 8\]

The image below shows a virus which reproduces using the lytic or lysogenic cycle.  

:::center
![BI0852](question:4fce213f-27b7-4257-a411-d60215b5fe41)
:span[\[© Revision Village 2023. Created with Biorender.com\]]{style="font-size:14px; line-height:1"}
:::

1. State two structural features common to all viruses.		:marks[2]

2.  
    1. Identify the name of this virus. 				:marks[1]

    2. Label the capsid on the image.  				:marks[1]

3. Compare and contrast the lytic and lysogenic cycles.  		:marks[4]




\[Maximum mark: 8\]

The image below shows the human immunodeficiency virus (HIV).

:::center
![BI0853A](question:4cfe17d4-c76f-480f-a1c8-30706d425537)
:span[\[© Revision Village 2023. Created with Biorender.com\]]{style="font-size:14px; line-height:1"}
:::

1. Explain the function of structure X.		:marks[2]

2.
    1. Identify structure Y. 				:marks[1]

    2. Identify structure Z.  				:marks[1]

3. State the host of this virus.			:marks[1]

4. Describe the metabolic functions of reverse transcriptase.  	:marks[3]

Which of the following components of some viruses are not present in both the bacteriophage and coronavirus?

:br

::indent
- A.$\hspace{1em}$ Genetic information surrounded by a capsid

- B.$\hspace{1em}$ RNA genome

- C.$\hspace{1em}$ Enzymes for replication

- D.$\hspace{1em}$ Structures for attachment to a host cell

Some bacteriophages infect host bacteria using the lytic cycle or the lysogenic cycle.
Which process is characteristic of the lysogenic cycle but not the lytic cycle?

:br

::indent
- A.$\hspace{1em}$ Phage DNA is injected into the host cell.

- B.$\hspace{1em}$ The phage inserts DNA into host DNA, forming a prophage.

- C.$\hspace{1em}$ Host bacterium is killed by cell lysis.

- D.$\hspace{1em}$ Phage proteins bind to receptors on the host bacterium cell.

Which is not a factor in the rapid evolution of the human immunodeficiency virus?

:br

::indent
- A.$\hspace{1em}$ Genetic recombination

- B.$\hspace{1em}$ High mutation rate

- C.$\hspace{1em}$ Slow replication rate  

- D.$\hspace{1em}$ Genetic diversity of host population



The origin of viruses is an area of active research and exploration. Which statement is not evidence that viruses have origins in other organisms?

:br

::indent
- A.$\hspace{1em}$ Similarities between genome sequence in viral and cellular genes.

- B.$\hspace{1em}$ Coevolution of viruses and host.

- C.$\hspace{1em}$ Retroviral enzymes such as reverse transcriptase convert RNA to DNA. 

- D.$\hspace{1em}$ Rate of mutation is rapid in viruses. 

A diagram of HIV is shown below. Which structure is composed of glycoproteins?  

:br

:::center
![BI0850](question:24bba3f7-b735-4ee4-a260-c806279fb3d8)
:span[\[© Revision Village 2023. Created with Biorender.com\]]{style="font-size:14px; line-height:1"}
:::

\[Maximum mark: 16\]

1. Outline the varied forms of genetic material found in viruses.	:marks[4]

2. Discuss the evidence supporting that the diversity of viruses exists as a result of convergent evolution.	:marks[4]

3. Compare the structure of the coronavirus with the human immunodeficiency virus, HIV. :marks[7]



\[Maximum mark: 16\]

1. Outline the methods of HIV transmission and its effects on the immune system.	 :marks[3]

2.	Discuss the need for international cooperation to fight contagious diseases such as Ebola. :marks[4]

3.	Antibiotics are an essential tool of modern medicine. Outline the strengths and limitations of antibiotics. :marks[8]


Which is **not** characteristic of HIV?

:br

::indent
- A.$\hspace{1em}$ The viral RNA encodes for reverse transcriptase

- B.$\hspace{1em}$ Spike glycoproteins allow for entry into CD4 cells

- C.$\hspace{1em}$ Two single strands of RNA are encased in a capsid

- D.$\hspace{1em}$ Integrase proteins are required for entry into a host cell


Structure & Diversity, Lytic Cycle, Lysogenic Cycle, Origins, Rapid Evolution of HIV & Influenza Viruses

HL - 2025

Unity & Diversity

A1.1 Water

BI0177

BI1013

BI1006

BI1008

BI1010

BI1012

BI1014

BI0769

BI1018

A1.2 Nucleic Acids

BI0321

BI0840

BI0891

BI0892

BI0893

BI0894

BI0895

BI0900

BI1067

A2.1 Origin of Cells		

BI0832

BI0945

BI0946

BI0947

BI0948

BI1721

BI0425

BI0810

BI1068

A2.2 Cell Structure

BI0753

BI0420

BI0756

BI0533

BI0418

BI0424

BI1050

A2.3 Viruses

BI0842

BI0843

BI0845

BI0847

BI0848

BI0850

BI0852

BI0854

A3.1 Diversity of Organisms

BI1027

BI1028

BI1029

BI1030

BI1031

BI1034

BI1035

A3.2 Classification & Cladistics		

BI0265

BI0266

BI0267

BI0269

BI0510

BI0272

BI0273

BI0274

A4.1 Evolution & Speciation

BI0706

BI0712

BI0863

BI0865

BI0868

BI0856

BI0857

BI0715

BI0870

A4.2 Conservation of Biodiversity

BI0903

BI0901

BI0902

BI0907

BI0908

BI0909

BI0911

Polarity, Hydrogen Bonding, Solvent Properties, Physical Properties, Consequences, Extraterrestrial Life

Water

BI0182

BI0183

BI0181

BI1007

BI1011

BI0178

BI0186

BI0668

BI1009

BI0187

BI0835

BI0834

BI0836

BI1015

BI1046

BI1224

BI1320

BI1407

BI1424

BI1537

RNA & DNA Structure, Antiparallel, Complementarity, Directionality, Nucleosome, Hershey-Chase, Radioisotopes, Chargaff

Nucleic Acids

BI0040

BI0541

BI0421

BI0047

BI0045

BI0043

BI0605

BI0038

BI0896

BI0314

BI0899

BI0897

BI0898

BI0322

BI0049

BI0313

BI0498

BI1047

BI1048

BI0841

BI1145

BI1166

BI1171

BI1221

BI0039

BI1382

BI1394

BI0042

BI1406

Conditions of Early Earth, Living vs. Nonliving, Origin of Cells, Miller-Urey Experiment, LUCA

Origin of Cells

BI0419

BI0415

BI1164

BI1392

BI1527

BI1715

BI1720

BI1525

BI1521

BI1523

BI1524

BI1526

Cell Structure, Functions of Life, Microscopy, Atypical Cells, Endosymbiosis, Differentiation, Multicellularism

IB Biology HL - 2025 - Questionbank

A2.3 - Viruses

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

Question 11

Question 12

Question 13

Question 14

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