Assignment 1 Unit 10
Rafaela Gaspar ID 192763
BTEC Applied Science Level 3
School Year – 2019/2020
,Rafaela Gaspar 192763Rafaela Gaspar 192763
Task A
Produce a leaflet to explain the links between the structure, function and roles of the
following biological molecules in living organisms:
o Water, structure and bonding and importance.
o Carbohydrates, including simple diagrams to show the CHO ratio compared to
other molecules and how simple sugars combine.
o Proteins, including the four levels of structure (primary, secondary, tertiary,
quaternary) and side group structure and function.
o Nucleic acids (DNA and RNA), including diagrams to compare the structures and
functions of these in the human body.
o Lipids, including saturated fats, unsaturated fats, as well as the formation of
diglycerides and triglycerides.
You could include photos of models and/or relevant referenced diagrams of the biological
molecules. State which chemical elements he molecules are formed from. Explain how the
addition of elements (such as nitrogen, phosphorus and sulphur) can alter the structure
and properties of the biological molecules.
Water structure and importance
o Water structure
Water is a small molecule that consists of two hydrogen atoms that are covalently bonded to
an oxygen atom. Because oxygen is more electronegative than hydrogen, the electron are
evenly distributed. Oxygen having a greater electronegative compared to hydrogen makes the
water molecule have regions of slight negative charge near to the oxygen and slight positive
charges near to the hydrogens due to the oxygen atom pulling the electrons to itself and away
from the hydrogen atoms. This is described as a polar molecule – a molecules with partial
positive and partial negative charges.
Text Ref: Annets, F., Hartley, J., Meunier, C., Llewellyn, R. and Hocking, S. (n.d.). Pearson BTEC National
applied science.
Figure 1
Image Ref: Cdn.kastatic.org. (2020). [online] Available at: https://cdn.kastatic.org/ka-perseus-
images/c8f5a3e5a16f2fc0a4fdd54eab7204ca39f836be.png [Accessed 16 Jan. 2020].
, Rafaela Gaspar 192763Rafaela Gaspar 192763
o Importance of water
Most living organisms need water to survive, water is important and has many functions and
roles in the living organisms’ lives.
Transport of molecules.
Water us a great transport medium in living organisms because it stays in the liquid
state over a wide temperature range. I has a high boiling point and a low melting
point.
Medium for chemical reactions.
Polar molecules will dissolve in water, this is because the substance that needs to be
dissolved also has an even charge distribution across the molecule, just like water.
Interaction with water molecule and the solute implies that the water molecule
collects around the charged parts of the solute, this makes the solute molecule to
break and dissolve and this leads to a freedom of particles that can move around and,
consequently, interact with other molecules. Therefore, water us a good solvent for
chemical reactions.
Temperature regulator.
It was mentioned before that water stays in the liquid state over a large temperature
change, this also suggests that water can take a lot of energy before changing
temperature, so it takes time to increase water temperature if the temperature outside
changes drastically, and this same statement applies for decrease in temperature. This
happens due to the hydrogen bonds that give an additional strength to water. Living
organisms that live in water will not be exposed to potentially life-threatening
temperature changes. The fact that water does not change temperature rapidly enables
these organisms to regulate their internal body temperature.
Regulating pH
Water has a pH of 7, which, at this pH, contains equal concentration H+ and OH-
ions. Living organisms are extremely sensitive to pH. Solutions found in blood stop
the pH changing when hydrogen or hydroxide ions are added. Water can accept and
donate H+ when necessary and therefore, pH may be kept steady. Without water,
solution wouldn’t be able to regulate and keep the pH required.
Electrolyte balance.
For instance, when extracellular electrolyte concentration rises, water diffuses out of
the cell by osmosis into the extracellular space, diluting the extracellular fluid and
raising the intracellular electrolyte concentration level.
Text Ref: Annets, F., Hartley, J., Meunier, C., Llewellyn, R. and Hocking, S. (n.d.). Pearson BTEC
National applied science.
Rafaela Gaspar ID 192763
BTEC Applied Science Level 3
School Year – 2019/2020
,Rafaela Gaspar 192763Rafaela Gaspar 192763
Task A
Produce a leaflet to explain the links between the structure, function and roles of the
following biological molecules in living organisms:
o Water, structure and bonding and importance.
o Carbohydrates, including simple diagrams to show the CHO ratio compared to
other molecules and how simple sugars combine.
o Proteins, including the four levels of structure (primary, secondary, tertiary,
quaternary) and side group structure and function.
o Nucleic acids (DNA and RNA), including diagrams to compare the structures and
functions of these in the human body.
o Lipids, including saturated fats, unsaturated fats, as well as the formation of
diglycerides and triglycerides.
You could include photos of models and/or relevant referenced diagrams of the biological
molecules. State which chemical elements he molecules are formed from. Explain how the
addition of elements (such as nitrogen, phosphorus and sulphur) can alter the structure
and properties of the biological molecules.
Water structure and importance
o Water structure
Water is a small molecule that consists of two hydrogen atoms that are covalently bonded to
an oxygen atom. Because oxygen is more electronegative than hydrogen, the electron are
evenly distributed. Oxygen having a greater electronegative compared to hydrogen makes the
water molecule have regions of slight negative charge near to the oxygen and slight positive
charges near to the hydrogens due to the oxygen atom pulling the electrons to itself and away
from the hydrogen atoms. This is described as a polar molecule – a molecules with partial
positive and partial negative charges.
Text Ref: Annets, F., Hartley, J., Meunier, C., Llewellyn, R. and Hocking, S. (n.d.). Pearson BTEC National
applied science.
Figure 1
Image Ref: Cdn.kastatic.org. (2020). [online] Available at: https://cdn.kastatic.org/ka-perseus-
images/c8f5a3e5a16f2fc0a4fdd54eab7204ca39f836be.png [Accessed 16 Jan. 2020].
, Rafaela Gaspar 192763Rafaela Gaspar 192763
o Importance of water
Most living organisms need water to survive, water is important and has many functions and
roles in the living organisms’ lives.
Transport of molecules.
Water us a great transport medium in living organisms because it stays in the liquid
state over a wide temperature range. I has a high boiling point and a low melting
point.
Medium for chemical reactions.
Polar molecules will dissolve in water, this is because the substance that needs to be
dissolved also has an even charge distribution across the molecule, just like water.
Interaction with water molecule and the solute implies that the water molecule
collects around the charged parts of the solute, this makes the solute molecule to
break and dissolve and this leads to a freedom of particles that can move around and,
consequently, interact with other molecules. Therefore, water us a good solvent for
chemical reactions.
Temperature regulator.
It was mentioned before that water stays in the liquid state over a large temperature
change, this also suggests that water can take a lot of energy before changing
temperature, so it takes time to increase water temperature if the temperature outside
changes drastically, and this same statement applies for decrease in temperature. This
happens due to the hydrogen bonds that give an additional strength to water. Living
organisms that live in water will not be exposed to potentially life-threatening
temperature changes. The fact that water does not change temperature rapidly enables
these organisms to regulate their internal body temperature.
Regulating pH
Water has a pH of 7, which, at this pH, contains equal concentration H+ and OH-
ions. Living organisms are extremely sensitive to pH. Solutions found in blood stop
the pH changing when hydrogen or hydroxide ions are added. Water can accept and
donate H+ when necessary and therefore, pH may be kept steady. Without water,
solution wouldn’t be able to regulate and keep the pH required.
Electrolyte balance.
For instance, when extracellular electrolyte concentration rises, water diffuses out of
the cell by osmosis into the extracellular space, diluting the extracellular fluid and
raising the intracellular electrolyte concentration level.
Text Ref: Annets, F., Hartley, J., Meunier, C., Llewellyn, R. and Hocking, S. (n.d.). Pearson BTEC
National applied science.
