Unit 1 Biological Molecules (Water) Flashcards
What is the relation between water and the cells?
Water is a major component of cells
What are 3 uses for water that prove it to be useful?
As a reactant in cells (photosynthesis and hydrolysis)
Provides structural support in cells
Keeps organisms cool to maintain an optimum body temperature
What are the 7 properties of water that make it very useful?
Liquid state
Reactant / Metabolite
Density
Solvent
Cohesion & Surface Tension
High Specific Heat Capacity
High Latent Heat of Vaporisation
What elements are water molecules made up of?
On oxygen atom and 2 hydrogen atoms
What type of molecule is water?
A polar molecule
What charge do the oxygen atoms have in a water molecule?
Oxygen atoms in water are slightly negatively charge
What charge do the hydrogen atoms have in a water molecule?
The hydrogen atoms have a slightly positive charge
What does the polarity of water molecules mean?
It means that a hydrogen atom on one water molecule is attracted to the oxygen atom on another water water molecule this is hydrogen bonding
What is the relation between warm-blooded animals and the high-heat capacity of water?
Water is used by warm-blooded animals to more evenly disperse heat in their bodies
What is the specific latent heat of vaporisation?
The amount of energy needed to change 1 kg of a liquid substance to a gas
In a water molecule how are 2 hydrogen atoms bonded together?
They are covalently bonded together
How does oxygen pull electrons?
Oxygen has a greater affinity for electrons than the hydrogen atom so it pulls the electrons
What Greek letter is used to represent the slight negative or positive charge in oxygen or hydrogen atoms?
Delta positive or Delta negative
Due to the oxygen being slightly negative and the hydrogen being slightly positive what happens to water?
Water comes to have 2 defined charged regions making it a dipolar molecule
The properties of water are caused by what?
The hydrogen bonds within water
What happens to the structure of water if there are many hydrogen bonds?
The structure of water is more stable
What is the impact of water being a liquid state to organisms?
Liquid state water provides a habitat for aquatic organisms.
What are the 2 impacts of liquid state water to cells within an organism?
It acts as a medium to surround cells as they are major component of cells
It also acts as a transport medium such as consisting of 90% of blood plasma
Name 3 reactions in which water is used as a reactant / Metabolite?
Photosynthesis
Condensation
Hydrolysis
Compare the density between Ice and water?
Ice is less dense than water which means ice forms on the surface of water
If ice forms on the surface of water what happens?
It is able to insulate the water underneath
What is the relation between the aquatic organisms and the density of ice on the surface of water?
Since ice is less dense than water and it resides on the surface of water, it provides a habitat for aquatic organisms as a stable environment
What solvent is water also known as?
The Universal solvent
Why is water a good solvent?
Substances can easily dissolve in water.
Why can polar molecules readily dissolve in water?
Polar or charged molecules can readily dissolve in water because water is dipolar molecule
What are polar molecules that dissolve in water also known as?
They are hydrophilic which means that they are attracted to water
What are non-polar molecules that don’t dissolve in water also known as?
They are hydrophobic which means they are repulsed by water
What is cohesion?
Water molecules sticking together due to the hydrogen bonds
What is adhesion?
Water molecules sticking to other things.
How can cohesion of water help small invertebrates?
Cohesion water provides habitats on the surface of water as well a method of escaping predators
How is there high specific heat capacity of water?
Water has lots of hydrogen bonds which means it requires a lot of heat energy to break the hydrogen bonds between water molecules
How is high heat capacity of water helpful for aquatic organisms
High heat capacity means that water is relatively stable even if the temperature fluctuates.
What is an internal process within organisms that is not affected by the high heat capacity of water?
The high heat capacity of water can’t affect the denaturation of enzymes when temperature fluctuates.
What is the latent heat of vaporisation of water?
The amount of energy required to break the hydrogen bonds of water from liquid state to gas state
Give a body example of high latent heat of vaporisation of water?
The latent heat of vaporisation of water is shown in the release of heat energy from the skin when it is transferred to sweat that evaporates.
What is the meaning of affinity?
An attraction between charges.
(E*) What bodily process would be hindered by a lack of water?
Digestion
(E*) What is the most abundant molecule on the Earth within in the atmosphere?
Water
(E*) Define Water’s property of cohesion?
It has intermolecular forces between the water molecules
(E*) Why does ice float on water?
The lattice structure of ice created through hydrogen bonding makes ice less dense than the free flowing molecules of liquid water
