Which of the following is a reason for the retention of water on Earth?

:br

::indent
- A.$\hspace{1em}$ Different patterns of rainfall across the continents

- B.$\hspace{1em}$ The gravitational force of the Moon

- C.$\hspace{1em}$ Earth temperatures being high enough for evaporation

- D.$\hspace{1em}$ The force of gravity on Earth

What intermolecular bond is responsible for water's cohesive, adhesive and thermal properties? 

:br
::indent
- A. $\hspace{1em}$ Covalent bond

- B. $\hspace{1em}$ Hydrogen bond
- C. $\hspace{1em}$ Ionic bond
- D. $\hspace{1em}$ Metallic bond


What property of water helps living organisms maintain their internal body temperature? 

:br
::indent
- A. $\hspace{1em}$ Thermal properties

- B. $\hspace{1em}$ Cohesive properties
- C. $\hspace{1em}$ Adhesive properties
- D. $\hspace{1em}$ Solvent properties


What is the most accepted theory for the origin of water on Earth?

:br

::indent
- A.$\hspace{1em}$ Asteroids from space containing ice arrived on Earth billions of years ago

- B.$\hspace{1em}$ Respiration from early organisms released water into the atmosphere

- C.$\hspace{1em}$ Heat from ancient deep-sea vents catalysed the reaction between hydrogen and oxygen atoms

- D.$\hspace{1em}$ Early volcanic eruptions, released steam into the atmosphere

Which of the following is not soluble in water?

:br
::indent
- A. $\hspace{1em}$ Glucose
- B. $\hspace{1em}$ Amino Acids
- C. $\hspace{1em}$ Cholesterol

- D. $\hspace{1em}$ Sodium Chloride


What substances are attracted to water and form intermolecular bonds with water molecules? 

:br

::indent
- A. $\hspace{1em}$ Insoluble substances

- B. $\hspace{1em}$ Hydrophobic substances
- C. $\hspace{1em}$ Hydrophilic substances
- D. $\hspace{1em}$ Non-polar substances


Which is the correctly annotated diagram of a molecule of water?

:br 

![BI1011](question:e88afb6d-e256-4dbc-85d0-f920b49cde92)

\[Maximum mark: 6\]
1. Outline how hydrogen bonds form between water molecules. :marks[2]

2. State one of the ways how hydrophilic substances interact with water. :marks[1]

3.  State one of the ways how non-polar molecules interact with water.:marks[1]

4. Distinguish between cohesion and adhesion.:marks[2]


The micrograph below shows the longitudinal cross-section of a stem from a plant in the *Pinus* genus.  Xylem vessels are clearly visible.

:::center
![BI1046](question:a56a5858-4bcb-449c-b27e-2d6d5a622fdd)
Magnification: 100X

:span[\[Source: From Berkshire Community College Bioscience Image Library. (2014). *Radial section: Pinus stem magnification: 100x iron-alum hematoxylin and safranin stain*. Wikimedia Commons. Retrieved April 29, 2022, from https<NO LINK>://commons.wikimedia.org/wiki/File:Gymnosperm_Stem_Soft_Wood_in_Pinus_(36087426450).jpg. 
 Copyright by CC BY CC0 1.0
\]]{style="font-size:14px; line-height:1"}
:::

The xylem is composed of hollow, tube-like tissues that transport water through capillary action. What property of water explains capillary action? 

:br

::indent
- A.$\hspace{1em}$ Melting point

- B.$\hspace{1em}$ Adhesive properties

- C.$\hspace{1em}$ Specific heat capacity

- D.$\hspace{1em}$ Buoyant forces

The image shows the vascular tissue in the leaves of a corn plant (*Zea mays*). What property of water is not demonstrated in the vascular tissue of the plant?

:::center
![BI1224](question:2ff3d4f0-e8cd-4249-9307-e959ca83e346)

:span[\[Source: Adapted from Berkshire Community College  Bioscience Image Library. (2017, October 3). *Angiosperm morphology: The closed and collateral vascular bundle in Zea*. Flickr. Retrieved September 11, 2023, from https<no link>://www<no link>.flickr.com/photos/146824358@N03/37215761790. Copyright free\]]{style="font-size:14px; line-height:1"}
:::

:br

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

- B.$\hspace{1em}$ Adhesion

- C.$\hspace{1em}$ Universal solvent

- D.$\hspace{1em}$ High thermal conductivity

Which of the following is a reason that the Earth is considered to be in ‘The Goldilocks zone’, but Saturn is not?

:br

::indent
- A.$\hspace{1em}$ The Earth is at an optimal distance from the Sun for water to be in three states, whereas Saturn has rings of ice

- B.$\hspace{1em}$ Saturn is able to form rings, but the Earth does not have rings

- C.$\hspace{1em}$ The Earth is at an optimal distance from the Sun for water to remain liquid, whereas Saturn is not

- D.$\hspace{1em}$ The Sun is visible from Earth but not from Saturn

Which of the following statements about the dipolarity of the water molecule are true? 
::indent
- I. $\hspace{1em}$ Oxygen attracts the shared electrons stronger than hydrogen.
- II. $\hspace{.7em}$ Hydrogen atoms are partially negative. 
- III. $\hspace{.4em}$ The shared electrons spend more time closer to oxygen. 

:br

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

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


Which of the following is **not** a reason that scientists look for the presence of water on planets as a sign of extraterrestrial life?

:br

::indent
- A.$\hspace{1em}$ Water is a necessary resource for most living organisms

- B.$\hspace{1em}$ Most enzymes catalyse reactions in solutions containing water

- C.$\hspace{1em}$ Water molecules can stick to each other

- D.$\hspace{1em}$ Water is a universal solvent


The cohesive and adhesive properties of water allow xylem vessels to transport water inside plants. 

Which of the following are correct descriptions of how these properties are related to water transport in plants?

:br

:::tableoptions{col1="hide"}
| | Cohesive | Adhesive |
| :-: | :-: | :-: |
| $\hspace{1em}$A.$\hspace{1em}$| Polar water molecules are attracted to one another and form hydrogen bonds. | Polar water molecules are attracted to the hydrophilic cell walls in xylem.
|$\hspace{1em}$B.$\hspace{1em}$ | Water molecules are polar, so are able to dissolve ions | Polar water molecules are attracted to one another and form hydrogen bonds. |
| $\hspace{1em}$C.$\hspace{1em}$ | Polar water molecules are attracted to one another and form oxygen bonds. | Water molecules are polar, so are able to dissolve ions |
| $\hspace{1em}$D.$\hspace{1em}$ | Polar water molecules are attracted to the hydrophilic cell walls in xylem. | Polar water molecules are attracted to one another and form hydrogen bonds. |


The image shows a water strider (*G. lacustris*) on the surface of a pond. What property of water is not depicted in the image?

:::center
![BI1013](question:59e027ec-d597-4a15-a9f6-8f2f194143b9)
:span[\[Source adapted from: Zinogre. (2021, July 11). *File: Aquarius paludum 142592609.jpg*. Wikimedia Commons. Retrieved July, 04 2023, from https<no link>://commons.wikimedia.org/wiki/File: Aquarius_paludum_142592609.jpg. Copyright free\]]{style="font-size:14px; line-height:1"}
:::

:br

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

- B.$\hspace{1em}$ Exertion of buoyant forces

- C.$\hspace{1em}$ Cohesion

- D.$\hspace{1em}$ Thermal conductivity

Which term to describe a property of water is matched to its correct definition?

:br 

:::tableoptions{col1="hide"}
| | Term | Definition |
| --- | :-: | :-: |
| A.$\hspace{1em}$ | Exerts buoyant forces | A lot of energy is needed to turn water into a vapour |
| B.$\hspace{1em}$ | High specific heat capacity | A lot of energy is needed to raise the temperature of water by 1 °C |
| C.$\hspace{1em}$ | High boiling point | Turns from ice into steam at 100 °C |
| D.$\hspace{1em}$ | Low viscosity | Easily allows objects to float on the surface |
:::

\[Maximum mark: 6\]

The photograph below is of the sea oat (*Unola paniculata*). This plant is found on sand dunes. 

:::center
![BI1424](question:54f3a7af-d48b-4bb1-9278-4e35299e8584)
:span[\[Source: Adapted from Daniel Di Palma (2 Feb 2017) *Miami Beach - Sand Dune Flora - Sea Oats in South Beach*. Retrieved 31 Jan 2024 from https<no link>://commons.wikimedia.org/w/index.php?curid=59792482. Copyright CC BY-SA 4.0\]]{style="font-size:14px; line-height:1"}
:::

:br 

1. Explain how the sea oat (*Unola paniculata*) is adapted to survive in its environment.	:marks[3]   

2. Describe the importance of the solvent properties of water for transport in plants and humans.			:marks[3]

\[Maximum mark: 4\]

The image shows a ringed seal (*Pusa hispida*) that lives in the Arctic Sea.
 
:::center
![BI0835](question:d4b9a85b-c422-4e0a-b290-37d692fd87be)
:span[\[Source: Adapted from: Kingfisher. (2021, May 29). Pusa hispida. Wikimedia Commons. Retrieved from July 07, 2023, from https<no link>://commons.wikimedia.org/wiki/Pusa_hispida. Copyright free\]]{style="font-size:14px; line-height:1"}
:::


1. Distinguish between the physical properties of air and water that allow the seal to mostly live in the sea.	  :marks[2]

2. Ringed seals glide into the water head first from ice shelves, rather like humans diving into a pool head first. Explain the advantage of entering the water in this way rather than ‘belly-flopping’ into the water.    :marks[2]



\[Maximum mark: 1\]

Which of the following thermal properties of water is **incorrectly** matched?

:::center
:::tableoptions{col1="hide"}
| | Property | Water |
| --- | :-- | :-: |
| A.$\hspace{1em}$ | Melting Point | 0 $\degree$C |
| B.$\hspace{1em}$ | Specific Heat Capacity | 2.2 J $\text{g}^{-1}$ $\degree \text{C}^{-1}$ |
| C.$\hspace{1em}$ | Latent Heat of Vaporisation | 760 J $\text{g}^{-1}$ |
| D.$\hspace{1em}$ | Boiling Point | 100 $\degree$C |
:::

\[Maximum mark: 5\]

Below is a picture of a water strider ($\textit{Gerris sp.}$).

:::center
![BI0187i_2.2](question:98250f20-3d55-4380-b054-95cf70aeb72c)
:span[\[Source: Schnobby. (2010). *Water Strider*. Wikimedia Commons. Retrieved April 27, 2022, from https<nolink>://commons.wikimedia.org/wiki/File: Water_strider_in_a_pond.jpg. Copyright by CC BY-SA 3.0\]]{style="font-size:14px; line-height:1"}
:::

:br

1. Explain why the water strider ($\textit{Gerris sp.}$) does not sink. :marks[2]

2. Describe, using an example, the importance of water as a solvent in living organisms. :marks[3]


Which of the following is **not** a real-life example of adhesion?

:br

::indent
- A.$\hspace{1em}$ Surface tension on the surface of a lake 

- B.$\hspace{1em}$ Dew drops hanging off the tip of a blade of grass

- C.$\hspace{1em}$ Water coating the surface of the alveoli 

- D.$\hspace{1em}$ Water sticking to cellulose in cell walls 



\[Maximum mark: 10\]

An investigation was carried out into the effects of household detergents on aquatic habitats. Scientists tested the effect of different household detergents on the surface tension of water in order to better understand the impact they may have on organisms living on the surface. 

A paper clip was folded slightly on one side and rested on the surface of the water, maintained at a constant temperature and contained within a water tank. Drops of detergent solution were slowly added to the water tank until the paperclip sank to the bottom. The volume of detergent solution taken to sink the paperclip was recorded.

Detergent solutions were made by adding 5 ml of detergent to 15 ml of water.

:::center
![BI0769A](question:9e71bc21-aad0-4144-8d02-95f90edc6509)
:span[\[© Revision Village 2022. Created with Chemix (https<NO LINK>://chemix.org)\]]{style="font-size:14px; line-height:1"}
:::

The results are shown in the table. 

:::center
![BI0769B](question:f4fd6e73-53ac-412a-9235-7fae1711865e)
:::

1. State the relationship between the volume of detergent solution added and the surface tension of water. 	:marks[1]

2.
    1. For the **Easy Clean** detergent, calculate the mean number of drops of detergent needed to sink the paper clip. 	:marks[1]

    2. Estimate how many drops of **Easy Clean** detergent solution it would take to sink 5 paper clips. 	:marks[1]

3.
    1. State **one** variable, other than those given, which would need to be controlled in this experiment in order to achieve a valid result. 	:marks[1]

    2. Suggest **one** method that could be used to keep the water at a constant temperature. 		:marks[1]

    3. Explain the importance of maintaining water at a constant temperature. 	:marks[2]

    4. Identify **one** potential source of error in the methodology. :marks[1]

4. Suggest why different numbers of drops of detergent solution were needed to sink the paperclip between each type of detergent.  	:marks[2]

\[Maximum mark: 16\]

1. Outline how water is formed at the end of aerobic respiration.	:marks[3]

2. Explain how the properties of water allow it to be transported around a plant.	:marks[5]

3. Describe how plants transport carbohydrates from source to sink.	:marks[7]

\[Maximum mark: 6\]

The image shows a cross-section of the vascular tissue of a woody dicot stem, showing the annual rings of phloem and xylem. 

:::center
![BI0834](question:8191483b-15e2-4be1-b746-75ba3038686a)
:span[\[Source: Adapted from: Berkshire Community College Bioscience Image Library. (2014, February 10). File:Woody Dicot stem primary xylem in late one year  - wikimedia. Wikimedia commons. Retrieved July 07, 2023, from https<NO LINK>://commons.wikimedia.org/wiki/File:Woody_Dicot_Stem_Ray_System_in_Two_Year_Tilia_%2834997659262%29.jpg. Copyright free\]]{style="font-size:14px; line-height:1"}
:::

1. Explain how the properties of water allow it to be transported in the xylem.  :marks[3]

2. Describe a physical property of water, other than those that are important for the movement of water through the plant, that makes water essential for the survival of plants.    :marks[1]

3. Outline why plants cannot use water to transport lipids.    :marks[1]

4. If the temperature drops to -1:sup[o]C for a few hours suggest a reason why the water in xylem may not freeze.    :marks[1]


The black-throated loon (*Gavia arctica*) is a bird that lives near large bodies of water in cold climates.  Which of the following is a correct description of how the properties of water may make winter temperatures more moderate for the black-throated loon?

:br

::indent
- A.$\hspace{1em}$ Water has a relatively high specific heat capacity which buffers the environmental temperature.


- B.$\hspace{1em}$ Ice floats on water so insulates the liquid water beneath the ice.

- C.$\hspace{1em}$ Water has a low specific heat capacity which warms the surrounding air.

- D.$\hspace{1em}$ Water is dense which enables the black-throated loon to float.

\[Maximum mark: 9\]

The diagram shows a solar system very similar to ours, where five planets orbit a central star.

:::center
![BI1018](question:b5e55501-0c1e-425e-8da0-e61f7243b9e5)
:span[\[© Revision Village 2023\]]{style="font-size:14px; line-height:1"}
:::

1. Define the term “Goldilocks zone”.	:marks[1]

2.
    1. Label with the letter R the planet that is least likely to have extraterrestrial life present. 	:marks[1]

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

3.
    1. Some of the planets in this solar system have water present on them. Suggest where this water might have come from.	:marks[1]

    2. Explain why the planets referred to in part (i) have retained water, whereas others in this solar system have not.:marks[2]

4. Suggest one other biological molecule, other than water, that may be a sign of life on a planet.		:marks[1]

Which of the following statements explains how water has facilitated the evolution of life on Earth?

:br

::indent
- A.$\hspace{1em}$ Water acts as a catalyst for chemical reactions

- B.$\hspace{1em}$ Water acts as a solvent allowing chemical reactions to occur faster within it

- C.$\hspace{1em}$ Water acts in hydrolysis reactions allowing for the synthesis of large biological molecules

- D.$\hspace{1em}$ Water has a high latent heat of vaporisation so is able to convert between states easily

Which of the following statement(s) about the role of water as a solvent is correct?


::indent
- :::tableoptions{col1="hide" col2="hide"}
    | | |
    | :-- | :-- |
    | I. | Salt can dissolve in water because it is hydrophilic|
    | II. | Lipids cannot dissolve in water because they are non-polar |
    | III. | Cellulose can dissolve in water, as it is able to form hydrogen bonds |
    :::

:br

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

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

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

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


\[Maximum mark: 8\]

The *Allium* genus contains leeks, garlics and chives. The images below show two members of the *Allium* genus that are native to Lithuania and their associated chromosome numbers. Polyploidy events have occurred to produce *Allium oleraeceum*.

:::center
:::tableoptions{col1="hide" col2="hide" }
| ![BI1407A](question:8bab7929-0bd6-4141-be1e-51087f10847c) | ![BI1407B](question:b20d81ba-794e-4f15-aed0-f63bb438d293) |
| :-: | :-: |
| *Allium angulosum* | *Allium oleraeceum* |
| 2n = 16 | 4n = 32 |
:::
:::center
:span[\[Source: Adapted from Lefnaer, S. (2015, July 26). *Category: allium angulosum*. Wikimedia Commons. Retrieved January 8, 2023, from https<no link>://commons.wikimedia.org/wiki/File: Allium_angulosum_sl3.jpg. Copyright under CC BY 4.0\]]{style="font-size:14px; line-height:1"}

:span[\[Source: Adapted from Leidus, I. (2013, July 7). *File: allium oleraceum - rohulauk.jpg* - wikimedia commons. Wikimedia commons. Retrieved January 8, 2023, from https<no link>://commons.wikimedia.org/wiki/File:  Allium_oleraceum_-_rohulauk.jpg. Copyright under CC BY 3.0\]]{style="font-size:14px; line-height:1"}
:::

:br 

1. Suggest how polyploidy may occur in plants.	:marks[1]

2. Outline how polyploidy in a species can lead to speciation.		:marks[2]

3. With reference to plant hormones, explain the directional growth observed in the image of *Allium oleraceum*.		:marks[3]

4. Plants within the *Allium* genus often have bulbs which grow underground. Outline how bulbs can be considered sinks **and** sources in the process of translocation.		:marks[2]




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

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

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

A1.1 - Water

Question 1

Question 2

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