This simple revision quiz contains questions to help you revise the topic A1.1 Water.
This topic is all about the polarity of water molecules, hydrogen bonding and how the physical properties of water effect the adaptations of animals like the black throated loon and the ringed seal.
What causes cohesion between water molecules?
Water molecules are polar and attract each other due to hydrogen bonds between the H and O of adjacent molecules.
sweat heat capacity soil stems Cohesion sink raise aquatic High viscosity other buoyant carbohydrates Solvent hydrophilic water
The polarity of the covalent bonds between the atoms in the water molecule causes hydrogen bonds between the molecules. These give the following properties which are vital to the functions of living organisms:
- , water molecules attract each other - allows an unbroken column to rise up the of tall trees.
- Adhesion, water molecules are attracted to charged molecules - retains water in .
- - dissolves molecules such as ions, proteins and in blood plasma.
- High , large quantity of heat needed to the temperature of water, stable environments.
- heat of vapourisation, large quantity of heat to evaporate - as a coolant.
- The low of water allows it to flow easily in the ciculatory system.
- Animals are generally more dense than water so tend to but can be made by feathers or gas chambers retaining air.
Examiner hint - Use correct terminology. You need to know examples of how the properties of water are important to living systems.
Which of the following factors caused water to be retained on the surface of the earth?
Gravity retained water at the Earth's surface and the temperature ensured that water condensed to liquid or solid.
heat capacity attract hydrogen polar support properties hydrogen cohesion evaporation unequal oxygen
Water is a molecule; the oxygen atom is slightly negative and slightly positive due to the sharing of the electrons between hydrogen and . These small charges each other forming bonds. This largely accounts for the unique of water that make it an ideal liquid to life.
Properties caused by polarity include , adhesion, solvent properties, high and high heat of .
Examiner hint: Use the correct technical terms
Explanation/Examiner hint. You also need to link these properties to their importance to living organisms. This is in a further question on this page.
Water is an evaporative coolant that allows organisms to lose heat by evaporating. Which of the following organs does not lose heat in this manner?
The brain itself does not lose heat by evaporative cooling, blood circulates to the skin of the cranium to lose heat. Leaf, tongue and lung can all be used for evaporative cooling.
Which kind of bonds can form between water molecules?
Hydrogen bonds can form between the slightly positive hydrogen and slightly negative oxygen.
In a water molecule, what is meant by the 'positive pole'?
In a water molecule, the 'positive pole' is the area containing fewer electrons near its hydrogen atom nuclei
In a water molecule, what the area containing more electrons around the oxygen atom known as?
In a water molecule, name the area containing more electrons around the oxygen atom is known as the negative pole
Describe hydrogen bonds by filling the gaps with two of the following words:
strong weak covalent atoms poles
A hydrogen bond is a bond formed between the positive and negative of adjacent water molecules.
The positive pole around the hydrogen atoms is attracted to the negative pole around the oxygen atoms of water molecules.
Explain why water is a good substance for transport of molecules by filling in the gaps by dragging and dropping three of the following words:
diffuse clean react with dissolve hydrophilic viscosity
Water is a good substance for the transport of molecules in living things as it can easily a wide range of molecules. It also has low which allows aqueous solutions to travel through vessels.
Water is good for transport in living things as it can easily dissolve hydophilic molecules such as glucose, sodium chloride, oxygen, and many amino acids, allowing the transportation of these molecules in the flow of water. Low viscosity allows easy travel through tubular structures.
Which of the following statements relates to the cohesive property of water molecules that has importance to animals living in ponds and in transport of water in the xylem of plants?
Cohesion in water molecules in high because H-bonds make water molecules stick to each other more strongly. It causes surface tension in ponds and lakes and holds water in a single column in the xylem of plants.
Which of the following molecules are readily soluble in water?
Water has important solvent properties.
Polar molecules and ionic salts dissolve readily in water and this helps them to be transported in the blood.
Which property of water helps to keep lakes at relatively stable temperatures?
Because water has a high specific heat capacity, it takes a lot of energy to make it change temperature so bodies of water do not change temperature rapidly duing the day and night.
Some medicines are designed to dissolve in a glass of water.
What is the term used to describe polar molecules which are easily soluble in water?
Glucose, amino acids and salts are hydrophilic while cholesterol and other fats are hydrophobic.
Why, in the search for extaterrestrial life on distant planets, why is the Goldilocks zone an important consideration?
Water in liquid form is regarded as essential fo life, planets in the Goldilocks zone have suface temperatures suitable fo liquid water to be present on the planet. Ursus arctus and Arena sativa are elements of the Goldilocks faiy tale.
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