Identify the correct row in the table regarding the formation of vesicles.

:br 

:::tableoptions{col1="hide"}
| | Structure of vesicle | Feature of fatty acid tail | Formation |
| --- | :-: | :-: | :-: |
| A.$\hspace{1em}$ | monolayer | hydrophilic | spontaneous |
| B.$\hspace{1em}$ | bilayer | hydrophobic | spontaneous |
| C.$\hspace{1em}$ | monolayer | hydrophilic | induced |
| D.$\hspace{1em}$ | bilayer | hydrophobic | induced |
:::

Which of the following statements are reasons that RNA is believed to be the first genetic material?

::indent
- :::tableoptions{col1="hide" col2="hide"}
    | | |
    | :-- | :-- |
    | I. | RNA can form spontaneously when nucleotides are present |
    | II. | RNA contains ribose as its sugar |
    | III. | Miller demonstrated that organic molecules could be produced from a mixture of gases under conditions that simulated early Earth |
    :::

:br

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

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

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

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

Which statement(s) is/are a necessary requirement for the evolution of the first cells?

::indent
- :::tableoptions{col1="hide" col2="hide"}
    | | |
    | :-- | :-- |
    | I. | DNA having the ability to catalyse reactions |
    | II. | Polymerisation of carbon compounds |
    | III. | Spontaneous formation of vesicles |
    :::

:br

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

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

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

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

\[Maximum mark: 3\]

The diagram below shows the apparatus used in the experiments conducted by Miller and Urey. 

:::center
![image](question:3b57ece6-ab77-4c10-83ed-7c8f13d7ec98)
:span[\[Source: Carny. (2008, February 4). File: Miller-Urey Experiment-EN.SVG. Wikimedia Commons. Retrieved May 20, 2022, from https<nolink>://commons.wikimedia.org/wiki/File: Miller-Urey_experiment-en.svg.  Copyright free\]]{style="font-size:14px; line-height:1"}
:::

:br

Describe how this experiment showed that the origin of life was possible on early Earth. :marks[3]

\[Maximum mark: 1\]

Which role of RNA supports the hypothesis that it acted as the first genetic material?

:br

::indent
- A. $\hspace{1em}$ It functions as a primer during transcription

- B. $\hspace{1em}$ It functions as an enzyme used by ribosomes

- C. $\hspace{1em}$ It serves as a template for polypeptide synthesis

- D. $\hspace{1em}$ It transports amino acids during translation

In the early 19th century, vitalism was a widely accepted theory. This theory suggested that organic compounds, those found in living organisms, could only be produced through a "vital force" present in living matter. 

What was the role of urea in falsifying the theory of vitalism?

:br

::indent
- A.$\hspace{1em}$ Urea is produced by kidneys, indicating that living things can make organic compounds.

- B.$\hspace{1em}$ Urea can be produced in laboratories, indicating that living things cannot synthesize organic compounds.

- C.$\hspace{1em}$ Urea can be produced in laboratories, indicating that not only living things can synthesize organic compounds.

- D.$\hspace{1em}$ Urea is produced by the kidneys, indicating that not only laboratories can make organic compounds.


Louis Pasteur\'s famous experiments disproving spontaneous generation were replicated by placing broth into various flasks.

:::center
![BI0415](question:f97a0d29-a9d0-41b2-9be3-14423d5734e7)
:span[\[ © Revision Village. Created using BioRender.com \]]{style="font-size:14px; line-height:0"}
:::

:br

Which two flasks would show the presence of microorganisms in the results?

:br

::indent
- A. $\hspace{1em}$ R and S

- B. $\hspace{1em}$ S and Q
- C. $\hspace{1em}$ Q and R 
- D. $\hspace{1em}$ P and Q 



\[Maximum mark: 1\]

Evidence suggests that the last universal common ancestor was nitrogen-fixing. Which biological molecule might it have incorporated nitrogen into?

:br

::indent
- A. $\hspace{1em}$ Starch

- B. $\hspace{1em}$ DNA nucleotide

- C. $\hspace{1em}$ Ribose sugar

- D. $\hspace{1em}$ Fatty acid

\[Maximum mark: 1\]

All organisms evolve through natural selection. Which of the following is a direct effect of natural selection on living organisms?

:br

::indent
- A. $\hspace{1em}$ It promotes the accumulation of beneficial traits in organisms

- B. $\hspace{1em}$ It allowed the last universal common ancestor to outcompete other organisms within one generation

- C. $\hspace{1em}$ It allows organisms that are best adapted to their environment to survive

- D. $\hspace{1em}$ It explains how life began on Earth

Which statement(s) provide evidence for the common ancestry of all existing forms of cellular life?

::indent
- :::tableoptions{col1="hide" col2="hide"}
    | | |
    | :-- | :-- |
    | I. | The universality of the genetic code |
    | II. | The machinery for protein synthesis |
    | III. | Use of ATP as a common energy currency |
    :::

:br

::indent
- A.$\hspace{1em}$ I and II only

- B.$\hspace{1em}$ I and III only

- C.$\hspace{1em}$ II and III only

- D.$\hspace{1em}$ I, II and III

\[Maximum mark: 10\]

Louis Pasteur disproved the theory of spontaneous generation by showing that life did not spontaneously arise from non-living matter but came from existing microorganisms. In his experiment, he set up the following flasks:

I. Open straight-neck flask containing boiled broth.

II. Swan-neck flask containing boiled broth (neck allowed air to flow but trapped dust and microbes).

III. 
Control flask containing boiled broth and sealed from the air.


Researchers carried out a similar experiment to Louis Pasteur’s famous experiment, using the set-up below, and incubating the flasks at 30°C.


:::center
![spontaneous origin of cells flasks](question:e58dbdf5-c36e-4567-ad68-a5f3248068bd)
:span[\[© Revision Village 2023. Created with Chemix (https<NO LINK>://chemix.org)\]]{style="font-size:14px; line-height:1"}
:::

1. State the purpose of boiling the broth before placing it in some of the flasks.	:marks[1]

2.
    1. State two variables that must be controlled in this experiment.	:marks[2]

    2. Explain why it is important to have controlled variables in this study.	:marks[1]

3.
    1. State the letters of three flasks which would show signs of decomposition of broth. :marks[1]

    2. Explain your answer to part (i).	:marks[3]

4. Suggest, with reasons, how the results of the study would differ if the flasks were incubated at 4°C.	:marks[2]

\[Maximum mark: 11\]

Below is a diagram of *Euglena* a photosynthetic protist. It is a living cell which can carry out all the functions of life.

:::center
![BI1068](question:0e7cb70d-2847-4e53-88b4-d3e0f7ba6098)
:span[\[© Revision Village 2023\]]{style="font-size:14px; line-height:1"}
:::

1.
    1. State which function of life the flagellum is adapted for.	:marks[1]

    2. State which function of life is enabled by the contractile vacuole.	:marks[1]

2. Outline why viruses are not regarded as living organisms. :marks[2]

3. State two main principles of the cell theory				:marks[2]

4. Explain how the properties of phospholipids mean they naturally form vesicles when in aqueous solution. 		:marks[2]

5. Explain how the formation of vesicles was important in the evolution of cells.	:marks[3]


\[Maximum mark: 1\]

When early lifeforms first emerged on Earth, the levels of UV radiation were much higher than they are today. How did higher levels of UV radiation affect the conditions of the early Earth?

:br

::indent
- A. $\hspace{1em}$ Provided energy for photosynthesis, so plants produced higher levels of oxygen

- B. $\hspace{1em}$ Broke down gases into smaller molecules

- C. $\hspace{1em}$ Mutated DNA nucleotide sequences so that a variety of polypeptides were formed

- D. $\hspace{1em}$ Caused volcanoes to release gases into the atmosphere

\[Maximum mark: 16\]

1.  Describe how the primordial soup hypothesis (an aqueous mix of simple organic molecules) explains the origin of carbon compounds on Earth. :marks[3]

2.  Mitochondria are organelles that are thought to have evolved from early prokaryotes. Discuss whether mitochondria can be considered living or nonliving. :marks[4]

3.  Discuss the evidence and limitations for the existence of a last universal common ancestor. :marks[8]

Enzymes are needed to replicate and transcribe DNA. Ribosomes are needed to translate the DNA into enzymes. According to the “RNA world” hypothesis, what problem does this present for the first lifeforms to evolve on Earth? 

:br

::indent
- A.$\hspace{1em}$ Early life forms could not catalyse reactions.

- B.$\hspace{1em}$ Early life forms could not self-replicate.

- C.$\hspace{1em}$ Early life forms were unable to produce proteins.

- D.$\hspace{1em}$ Early lifeforms did not have cell membranes.

\[Maximum mark: 1\]

The diagram shows the phylogenetic tree of life. Which method **CANNOT** be used to estimate the ages of the first living cells?

:::center
![BI1524 fig1](question:10fab881-d56f-4a45-a814-a9e928554585)
:span[\[Source: Adapted from Croft, J. D. (2014, November 4). File: phylogenic tree-en.svg. Wikimedia Commons. Retrieved February 26, 2024 from URL https<nolink>://commons.wikimedia.org/wiki/File: Phylogenic_Tree-en.svg. Copyright under CC BY 3.0\]]{style="font-size:14px; line-height:1"}
:::

:br

::indent
- A. $\hspace{1em}$ Dating fossils using radioactive techniques

- B. $\hspace{1em}$ Genomic analysis of mutation rate

- C. $\hspace{1em}$ Analysis of stromatolites

- D. $\hspace{1em}$ Analysing fossils from ancient volcanic rocks

Louis Pasteur disproved the theory of spontaneous generation by showing that life did not spontaneously arise from non-living matter but came from existing microorganisms. In his experiment, he set up the following flasks:

Open straight-neck flask containing boiled broth.
Swan-neck flask containing boiled broth (neck allowed air to flow but trapped dust and microbes).
Control flask containing boiled broth and sealed from the air.

The experiment was replicated as shown below: 


:::center
![Pasteur flask RV](question:9f2606f0-633f-460c-b9ba-a9599ddfb669)
:span[\[ © Revision Village. Created using BioRender.com \]]{style="font-size:14px; line-height:0"}
:::

:br

Which two flasks would show the presence of microorganisms in the results?

:br

::indent
- A. $\hspace{1em}$ R and S

- B. $\hspace{1em}$ S and Q
- C. $\hspace{1em}$ Q and R 
- D. $\hspace{1em}$ P and Q 

Whose experiments **disproved** spontaneous generation?

:br

::indent

- A. $\hspace{1em}$ Miller and Urey

- B. $\hspace{1em}$	Louis Pasteur
- C. $\hspace{1em}$	Rosalind Franklin
- D. $\hspace{1em}$	Meselson and Stahl


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

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

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

A2.1 - Origin of Cells

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

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Question 10

Question 11

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Question 15

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