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New Students’ Day Activity
Bridging the Gap for AS Biology
Vocabulary
It is very important in biology that you use the appropriate terminology in your
answers. You will be familiar with many biological terms from GCSE. It is essential that
you understand them and use them accurately. Complete the following task.
Activity:
1. Use the word bank to find the correct biological term for each definition (not all
words will be used):
Eukaryote
Bacteria
Tissue
Enzyme
Nucleus
Photosynthesis
Active transport
Active site
Cytoplasm
Gene
Chromosome
Denature
Diffusion
Dilute
Respiration
Protein
Active transport
Homeostasis
Osmosis
Food chain
Mitosis
Biological term
Definition
Biological catalyst that increases the rate of reaction
Location on an enzyme where the substrate binds
Energy required for a reaction to take place
Fundamental building block of living organisms
A part of DNA that codes for a protein
Maintaining a constant internal environment
Movement of substance against a concentration gradient
A single-celled micro-organism with no nucleus
Found in all cells where chemical reactions take place
Organism that has a nucleus
Feeding relationship between different organisms in an ecosystem
When the shape of an enzyme changes so that it loses its function
Movement of molecules from an area of high to low concentration
Composed of DNA, found in the nucleus of a eukaryote
Cell division in which two identical daughter cells are produced
An organelle that contains the genetic material that controls the cell
Diffusion of water from an area of high concentration to an area of low
concentration
A group of cells that have a similar structure and function
Process carried out by plants in which light energy is used to produce glucose
Process where glucose is broken down to provide ATP energy
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Specialised Cells
These are examples of specialised cells.
Activity:
2. Carry out some research and choose any specialised cell that is of particular
interest to you.
a. Research four structures found within the cell that allow it to carry its particular
function.
b. Create a poster of the cell summarising the function of the four chosen
structures and the importance of this specialised cell within an organism.
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Biological molecules
Biological molecules are found in living organisms. All molecules are made up of atoms.
Polar molecule
This is a molecule that has a positive and negative side that
is caused by the atoms within the molecule sharing electrons
unevenly. In Biology we study the water molecule as a polar
molecule. The oxygen side of the molecule has more
electrons than the hydrogen side. This causes the oxygen
side to have a negative charge and the hydrogen side to have
a positive charge. Polar molecules tend to stick to one another as if they were magnets.
Cohesion between water molecules results from this attraction between water
molecules. It is essential for the movement of water up the xylem vessels in a plant.
Bonding
Atoms may combine with each other in a number of ways:
•
•
•
Covalent bonds – occur between 2 atoms that share valence electrons in order to
achieve 8 valence electrons.
Ionic bonds – occur between 2 oppositely charged ions. This bond occurs after
atoms give and take valence electrons in order to achieve 8 valence electrons.
Hydrogen bonds – a weak bond that forms when a hydrogen atom within one
molecule is attracted to a nitrogen, oxygen, or fluorine atom in another molecule.
Forming macromolecules
The term monomer is given to any subunit of a biological molecule. For example the
monomer of a protein is an amino acid. Monomers can be linked together to form long
chains called polymers. The process by which polymers are formed is polymerisation.
Condensation and hydrolysis reactions
•
Condensation reaction - occurs when two molecules combine to form a larger
molecule, with the elimination of water. For example the polysaccharide starch
is formed from the monosaccharide glucose.
•
Hydrolysis reaction – the breaking down of a large molecule into smaller ones,
with the addition of water. If you break down the meaning of the word then it is
very easy to remember since ‘hydro’ = water and ‘lysis’ = splitting. So proteins
can be hydrolysed into amino acids and starch can be hydrolysed into glucose.
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Activity:
3. Label one condensation and one hydrolysis reaction on the diagram below.
Glycerol &
Amino acids
Monosaccharides
Polypeptides
(Proteins)
Polysaccharides
(Carbohydrates)
Nucleotides
Polynucleotides
(Nucleic acids)
Fatty acids
Lipids
(Fats & oils)
4. Find and then condense the definitions for each of the following (6-8 words):
Biological term
Definition
Hydrogen bonds
Covalent bonds
Monomer
Polymer
Polymerisation
Condensation
Hydrolysis
Calculation skills
Mean = sum of all values
number of values
Rate = change
time
Magnification = image size
actual size
Pulmonary ventilation rate = tidal volume x breathing rate
Cardiac output = stroke volume x heart rate
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Activity:
5. Calculate the cardiac output for a student at rest where the stroke volume is 75cm3
per beat and heart rate is 75 beats per min.
6. Calculate the pulmonary ventilation rate for a student the tidal volume is 0.5dm3
per breath and breathing rate is 12 breaths per min.
7. If 40g of product was made by a reaction over 10 mins, what is the rate of
production per minute?
Activity - Under the microscope
Microscopes are used to study cells. Modern light microscopes can
magnify images about 1500X, while electron microscopes can magnify
images about 2,000,000X
Calculating magnification
Remind yourself of the equation you use to calculate magnification of a biological
specimen (pg4).
8. A plant cell in the photograph measures 15mm across. If the actual size of the cell
is 0.015mm, what is the magnification?
Calculating actual size
You can rearrange the equation so that:
Actual size = image size
magnification
9. The nucleus in a photograph of a cell measures 3mm across. If the magnification in
the photograph is x500, what is the actual size of the nucleus?
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Using the correct units
In biology it is vital you can use the correct units. It is important you develop good
habits right from the start, being careful to only use the correct abbreviation.
Common units
Measurement
Length
Mass
Volume
Time
Whole units
Metre (m)
Gram (g)
Litre (L/ dm3)
Second (s)
One thousand times
Kilometre (km)
Kilogram (kg)
Converting units
Calculations often require you to convert between units in order to be able to give the
answer in a sensible form.
Divide by 1000 for each step to convert in this direction
nanoe.g. nm
microe.g. um
millie.g. mm
whole unit
e.g. m
kiloe.g. km
Multiply by 1000 for each step to convert in this direction
Activities:
10. Complete the diagram below to show: names of the units of measurement, unit
symbols, mathematical operations for converting between units.
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11. Convert the following:
e.g. 1m to mm, e.g. 1 x 1000 = 1000 mm
a) 1m to um _______________________________________________
b) 1dm3 to cm3 _____________________________________________
c) 20,000 um to mm _________________________________________
12. Complete the table below to show the corresponding value nanometres, micrometres
and millimetres for the measurements given in each row. The first row has been
completed for you. Ensure that your answers use the correct unit symbols.
Nanometre
5
1
Micrometre
0.005
Millimetre
0.000005
1
1
3
7
0.5
13. When studying cells structure using a microscope the smallest unit of measurement
commonly used to describe findings is the nanometre.
Explain why.
Decimal places
Use an appropriate number of decimal places in calculations.
Be careful when calculating mean values. Your mean should have the same level of
precision as the original measurements and so the same number of decimal places.
e.g. mean mass is (6.2 + 7.7 + 6.7 + 7.1 + 6.3)/ 5 = 6.8g
Rounding
When the next number is 5 or more round up, if it is 4 or less don’t round up.
e.g. 4.75 rounds to 4.8
4.74 rounds to 4.7
14. Find the mean of these numbers: 3, 7, 5, 13, 20, 23, 39, 23, 40, 23, 14, 12, 56, 23, 29
15. Round the following to one decimal place: 10.765 and 1.488
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