National 5 Biology
Resources Guide
November 2014
NATIONAL 5 BIOLOGY RESOURCES GUIDE
Biology National 5 Resources Guide
This resource guide has been produced in response to requests from staff who attended the NQ Sciences events at Hampden Stadium in
December 2013. Those attending felt it would be useful to have a document which helped them navigate to the most relevant resources
quickly.
The following pages show the mandatory course key areas table from the SQA Biology National 5 Course and Unit Support Notes. An
additional fourth column has been included which contains hyperlinks to useful resources. Please note: Staff are not required to use the
resources listed – they are only included as helpful suggestions. Staff should also refer to the SQA website for the most up-to-date
course and unit support notes.
To further assist staff links to useful SQA documentation have been included at the beginning of each unit. The SQA documentation relating to
the course is shown here.
SQA documents
Web link
Course specification
http://bit.ly/1m3GVXu
Course assessment specification
http://bit.ly/1lj7sTv
Course and unit support notes (the original document which has been modified in the
succeeding pages)
General assessment information
Specimen examination paper and marking scheme
http://bit.ly/1dJVNFa
Course Report 2014
http://bit.ly/1EQMSyN
http://bit.ly/1mskOwK
http://bit.ly/1pvEOvN
Education Scotland learning materials
National Qualifications Glow portal
http://bit.ly/1jBggj3
Past papers guidance
http://bit.ly/1jqfMAF
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
Cell Biology
Mandatory course key areas
1 Cell structure
Cell ultrastructure and functions,
including cell wall, mitochondrion,
chloroplast, cell membrane, cytoplasm,
vacuole, nucleus, ribosome and
plasmid using examples from typical
plant, animal, fungi and bacterial cells.
Cell wall structure in fungal and
bacterial cells is different from plant
cells, ie not cellulose.
Unit specification: http://bit.ly/1gV5mkK
Suggested learning activities
Exemplification of key areas
Useful resources
Examine fresh and prepared
slides of a range of plant,
animal and microbial cells
using appropriate stains and a
light microscope/bioviewer, eg
cheek epithelium, onion
epidermis, rhubarb epidermis,
Elodea, yeast.
Numeracy activities on cell size
to investigate cell length and
breadth.
Functions of structures exemplified
later in this unit.
Fungal structure in terms of
similarity to plant and animal cells
but a different cell wall structure.
Bacterial structures only to include
absence of organelles and a
different cell wall structure to plant
and fungal cells. Chemical
composition of cell walls for fungi
and bacteria not required.
SSERC teacher resources – Cell structure
BBC Knowledge and Learning revision
guide – Cell structure
Biology Mad learner summary and
experiment – Cellular ultrastructure
PhET interactive simulation – Membrane
channels
University of New Mexico learner summary
– Cell structure and function
Twig video clip – What is a cell?
Twig video clip – Different types of cell
Twig video clip – Pandemic viruses
Twig video clip – Pandemic viruses (SARS)
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
2 Transport across cell membranes
(a) The cell membrane consists of
phospholipids and proteins and is
selectively permeable.
Highland Council resources – Transport
across cell membranes
(GLOW login required)
http://www.educationscotland.gov.uk/nqcou
rsematerials/subjects/b/nqresource_tcm47
55164.asp
Investigate the structure of the
fluid mosaic model.
(b) Passive transport is down a
concentration gradient and does
not require energy.
Investigate diffusion and
osmosis using visking tubing
and/or mass/length of plant
(c) Diffusion in cells as the movement tissue, bleeding in plant cells,
of molecules down a
plant cell plasmolysis, mass
concentration gradient.
changes in egg (shell removed
by soaking in vinegar) in
syrup/water.
(d) Osmosis in the movement of
water molecules from a high water
Research examples of osmosis
concentration to a lower water
for, for example, power
concentration through a
selectively permeable membrane. generation, desalination.
(e) Animal cells can burst or shrink
and plant cells can become turgid
or plasmolysed in different
solutions.
(f)
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Active transport requires energy
for membrane proteins to move
molecules and ions against the
concentration gradient.
Differential uptake of dye in
boiled and live yeast cells.
Different concentrations of
substances exist between cells
and their environment. Diffusion in
terms of concentration gradients
and importance to cells could
include glucose, carbon dioxide,
oxygen or amino acids.
SSERC teacher resources – Transport
across cell membranes
BBC Knowledge and Learning revision
guide – Transport across membranes
Biology Mad learner summary – Diffusion
Twig video clip – The cell membrane
Appropriate examples for active
transport could include sodium
and potassium in nerve cells, or
iodine in seaweeds.
These processes can be applied
across relevant areas of the
course.
NATIONAL 5 BIOLOGY RESOURCES GUIDE
3 Producing new cells
(a) Sequence of events of mitosis
(including the terms chromatids,
equator and spindle fibres).
(b) Maintenance of diploid
chromosome complement by
mitosis.
(c) Mitosis is required for growth and
repair.
(d) Cell production by cell culture
requires aseptic techniques, an
appropriate medium and the
control of other factors.
Select and present information
using mitosis stage cards.
Create model chromosomes.
Observe prepared root tip cell
slides/bioviewer.
Carry out numeracy activities
based on cell growth
graphs/curves.
Practical activity/investigation/
research into aseptic
techniques, solid and liquid
media in cell culture and use of
fermenters.
Names of mitosis phases are not
needed.
SSERC teacher resources – Producing
new cells
Diploid cells have two matching
sets of chromosomes, which are
replicated during mitosis.
BBC Knowledge and Learning revision
guide – Producing new cells
Appropriate growth media include
various nutrient broths and agars.
Appropriate factors could include
oxygen, temperature and pH.
Examples of how to achieve
aseptic conditions.
University of Leicester learner resource –
The cell cycle, mitosis and meiosis
Twig video clip – Cell division: mitosis
Twig video clip – Cell division: meiosis
Twig video clip – FactPack: Pregnancy
timeline
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
4 DNA and the production of
proteins
(a) Structure of DNA: double-stranded
helix held by complementary base
pairs. DNA carries the genetic
information for making proteins.
The four bases adenine, cytosine,
guanine and thymine (A, C, G and
T) make up the genetic code. A is
always paired with T, and C is
always paired with G.
The base sequence determines
the amino acid sequence in
protein.
(b) Messenger RNA (mRNA) is a
molecule that carries a
complimentary copy of the code
from the DNA, in the nucleus, to a
ribosome, where the protein is
assembled from amino acids.
6
Research the relationship
between chromosomes, genes,
DNA and protein to illustrate
that genes are located on
chromosomes.
Construction of 2D or 3D DNA
models. Paper models of base
pairing or DNA sections.
Carry out numeracy activities to
determine base pair numbers.
Research biologists, eg Watson Knowledge of uracil as a base in
and Crick, Rosalind Franklin,
mRNA is not required.
Maurice Wilkins, Chargaff.
Further details of transcription and
translation are not required.
SSERC teacher resources – DNA and the
production of proteins
BBC Knowledge and Learning revision
guide – DNA and the production of
proteins
Twig video clip – How does DNA make
protein?
Your genome.org learner activity – Origami
DNA
Nobelprize.org learner information – The
Discovery of the Molecular Structure of
DNA: The Double Helix
Teacher Tube video clip – DNA to RNA to
Proteins
NATIONAL 5 BIOLOGY RESOURCES GUIDE
5 Proteins and enzymes
(a)
The variety of protein shapes
Create protein models, eg
Levels of protein structure such as
and functions arises from the sequence haemoglobin, antibodies,
secondary/tertiary not required.
of amino acids.
membrane proteins and
enzymes.
(b)
Functions of proteins to include
structural, enzymes, hormones,
Use of appropriate software, eg
antibodies and receptors.
RasMol, Protein Explorer.
(c) Enzymes function as biological
catalysts and are made by all living
cells. They speed up cellular
reactions and are unchanged in
the process. The shape of the
active site of enzyme molecules is
complementary to a specific
substrate(s). Enzyme action
results in product(s). Enzymes can
be involved in degradation and
synthesis reactions. Examples
should relate enzymes to their
specific substrate(s) and
product(s).
SSERC teacher resources – Proteins and
enzymes
BBC Knowledge and Learning revision
guide – Proteins and enzymes
Chemguide learner resource – Protein as
enzymes
Twig video clip – FactPack on enzymes
Twig video clip – Tropisms and hormones
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
(d)
Each enzyme works best in its
optimum conditions. Enzymes and
other proteins can be affected by
temperature and pH. Enzymes
can be denatured, resulting in a
change in their shape, which will
affect the rate of reaction.
6 Genetic engineering
Genetic information can be transferred
from one cell to another naturally or by
genetic engineering. Stages of genetic
engineering to include identifying
section of DNA that contains required
gene from source chromosome,
extracting required gene, inserting
required gene into vector/bacterial
plasmid, inserting plasmid into host cell
and growing modified cells to produce a
genetically modified (GM) organism.
Use of enzymes in this process.
8
Enzyme experiments with, for
example, pepsin, lipase,
amylase and catalase to
investigate the influence of
temperature and pH on activity.
Effect of temperature and pH
on egg white as a model for
effect on other proteins.
Research current genetic
foods/issues such as golden
rice, less toxic rape seed oil,
bird resistance to bird flu,
tomatoes with longer shelf life,
blight-resistant potatoes,
production of medicines for
human use, eg insulin and
growth hormone.
DNA can be transferred naturally
between cells by either bacterial
plasmids or viruses. Details of
these processes not required.
Names of particular enzymes are
not required.
Links with Life on Earth unit.
SSERC teacher resources – Genetic
engineering
BBC Knowledge and Learning revision
guide – Genetic engineering
Twig video clip – Genetic modification
NATIONAL 5 BIOLOGY RESOURCES GUIDE
7 Photosynthesis
Photosynthesis is a two-stage process.
1. Light reactions: the light energy
from the sun is trapped by
chlorophyll in the chloroplasts and is
converted into chemical energy in
the form of ATP. Water is split to
produce hydrogen and oxygen.
Hydrogen attaches to hydrogen
acceptor molecules. Excess oxygen
diffuses from the cell.
2. (a) Carbon fixation: a series of
enzyme-controlled reactions that
use hydrogen and ATP (produced
by light reactions) with carbon
dioxide to produce sugar.
(b) The chemical energy in sugar is
available for respiration or can be
converted into other substances
such as starch (storage) and
cellulose (structural).
Oxygen production, carbon
dioxide uptake or rate of
photosynthesis can be
investigated through the use of
floating leaf discs, Elodea,
Cabomba or immobilised algae.
These can also be used to
investigate limiting factors.
Use IT simulations of
photosynthesis experiments, eg
Multimedia Science
Summary word equation for
photosynthesis:
Light energy
Carbon + water → sugar +oxygen
dioxide
Chlorophyll
SSERC teacher resources –
Photosynthesis
BBC Knowledge and Learning revision
guide – Photosynthesis
Twig video clip – Photosynthesis
Virginia Tech animation – Photosynthesis:
light reactions
Encylopedia Britannica article – Carbon
fixation and reduction
Factors affecting starch
production can be investigated
through iodine testing in leaves.
(c) Limiting factors: carbon dioxide
concentration, light intensity and
temperature, and their impact on
photosynthesis and plant growth.
Analysis of limiting factors graphs.
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
8 Respiration
(a) The chemical energy stored in
glucose must be released by all
cells through a series of enzymecontrolled reactions called
respiration.
Practical investigations on
burning food. Practical
investigations of DCPIP/
Cabomba and hydrogen
carbonate indicator.
SSERC teacher resources – Respiration
BBC Knowledge and Learning revision
guide – Respiration
Twig video clip – Respiration
(b) The energy released from the
breakdown of glucose is used to
generate ATP from ADP and
inorganic phosphate (Pi). The
chemical energy stored in ATP can
be released by breaking it down to
ADP and inorganic phosphate. This
energy can be used for cellular
activities including muscle cell
contraction, cell division, protein
synthesis and transmission of nerve
impulses. ATP can be regenerated
during respiration.
The breakdown of each glucose
molecule via pyruvate to carbon
dioxide and water in the presence
of oxygen yields 38 molecules of
ATP.
The breakdown of each glucose
molecule via the fermentation
pathway yields two molecules of
ATP when oxygen is not present.
10
Use immobilised yeast and
hydrogen carbonate indicator,
resazurin or gas sensors and
data loggers to investigate rate
of respiration.
Cells such as muscle, companion,
sperm, neurone will have a high
number of mitochondria as they
require a lot of energy.
Twig video clip – Anaerobic respiration
PBS Learning video clip – From DNA to
protein
Summary word equations for
Royal Society of Chemistry learner
Investigate respiration indirectly respiration:
through breathing rates before glucose + oxygen
 ca rbo resource – Respiration
and during exercise in humans. dioxide + water
glucose
 e tha PhET interactive simulation – Gene
carbon dioxide
expression: the basics
glucose
 la ctic a c
Links with Multicellular Organisms
unit.
NATIONAL 5 BIOLOGY RESOURCES GUIDE
Breakdown of glucose to lactic acid
via pyruvate in animal cells.
Breakdown of glucose to
alcohol/ethanol and carbon dioxide
via pyruvate in plant and yeast
cells.
(c) Respiration begins in the cytoplasm.
The process of fermentation is
completed in the cytoplasm. Aerobic
respiration starts in the cytoplasm
and is completed in the
mitochondria.
(d) Use of respirometers to measure
rate of respiration.
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
Multicellular Organisms
Mandatory course key areas
1 Cells, tissues and organs
Specialisation of cells, in
animals and plants, leads to the
formation of a variety of tissues
and organs. Groups of organs
which work together form
systems.
2 Stem cells and meristems
(a)
Stem cells in animals
can divide and have the
potential to become different
types of cell. Stem cells are
involved in growth and repair.
(b)
Meristems are the sites
of production of non-specialised
cells in plants and are the sites
for mitosis in a plant. These
cells have the potential to
become other types of plant cell
and they contribute to plant
growth.
12
Unit specification: http://bit.ly/OQJmBN
Suggested learning activities
Exemplification of key areas
Useful resources
Examine a variety of cells from
different tissues to relate their
structure to function.
Multicellular organisms have more than SSERC teacher resources – Multicellular
one cell type and are made up of
organisms
tissues and organs. Organs perform
different functions. The cells in organs
BBC Knowledge and Learning revision guide
are specialised for their function.
– Cells, tissues and organs
Specialisation can be applied to all
named tissues in this unit.
Biotopics learner guide – Cell structure and
specialisation
Use a variety of media to
investigate the potential uses of
stem cells and discuss ethical
issues associated with their
use.
SSERC teacher resources – Stem cells and
meristems
Carry out practicals on root
tip/shoot tip stain.
Twig video clip – Stem cells
BBC Knowledge and Learning revision guide
– Stem cells and meristems
EuroStemCell teacher resources – Stem cell
toolkit
NATIONAL 5 BIOLOGY RESOURCES GUIDE
3 Control and communication
(a) Nervous control
(i) Nervous system consists of
central nervous system (CNS)
and nerves. CNS consists of
brain and spinal cord. Structure
and function of brain to include
cerebrum, cerebellum and
medulla. Neurons are of three
types: sensory, relay and motor.
Receptors detect sensory
input/stimuli. Electrical impulses
carry messages along neurons.
A synapse occurs between
neurons. Chemicals transfer
these messages across
synapses.
(ii) Structure and function of
reflex arc.
(b) Hormonal control
(i) Endocrine glands release
hormones into the bloodstream.
Hormones are chemical
messengers. Target tissues
have cells with receptor proteins
for hormones, so only some
tissues are affected by specific
hormones.
Investigate examples of where
communication pathways are
used, eg pain receptors.
Internal communication is required for
survival of a multicellular organism.
Cells in multicellular organisms do not
work independently.
Sensory neurons pass the information
to the CNS. The CNS processes the
information from our senses which
needs a response. Motor neurons
enable a response to occur, which can
be a rapid action from a muscle or a
slower response from a gland.
SSERC teacher resources – Control and
communication
InnerBody interactive resource – Nervous
system: Anatomy explorer
BBC Knowledge and Learning revision guide
– Control and communication
Twig video clip – The nervous system
Twig video clip – Neurons as cells
Twig video clip – Cortisol and chronic stress
Investigate examples of human
reflex activities, eg blinking, iris
reflex, response to pain.
Research the role of hormones
in the body.
Diabetes as a communication
pathway that has failed due to a
fault in release or a failure to
respond to insulin, and
consequences and treatment.
Estrella Mountain Community College
learner resource – The endocrine system
Insulin production when blood glucose
levels are higher than normal and
production of glucagon when levels are
below normal.
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
(ii) Blood glucose regulation
including the role of insulin,
glucagon, glycogen, pancreas
and liver.
4 Reproduction
(a) The structure of gametes
and the sites of their
production in plants and
animals.
Cells are diploid, except
gametes, which are
haploid.
Investigate the causes and
treatment of both type 1 and
type 2 diabetes with reference
to trends in Scottish health
statistics.
Detail of negative feedback is not
required.
Compare and contrast male
and female animal and plant
gametes, gonads and organs
from micrographs, models,
reference materials,
photographs and dissection of
flowers.
Knowledge of polyploidy organisms is
not required.
EndocrineWeb learner resource – Insulin
regulation of blood glucose
Twig video clip – Insulin and diabetes
SSERC teacher resources – Reproduction
BBC Knowledge and Learning revision guide
– Reproduction
Twig video clip – Sperm
Twig video clip – Egg
(b) Fertilisation is the fusion of
the nuclei of the two
haploid gametes to
produce a diploid zygote.
14
Twig video clip – Fertilisation
NATIONAL 5 BIOLOGY RESOURCES GUIDE
5 Variation and Inheritance
(a) Comparison of discrete
and continuous variation.
(b) Most features of an
individual phenotype are
polygenic and show
continuous variation.
(c) Genetic terms including
gene, allele, phenotype,
genotype, dominant,
recessive, homozygous,
heterozygous and P1, F1
and F2. Carry out
monohybrid crosses from
parents through to F2.
Reasons why predicted
ratios are not always
achieved.
Investigate a variety of discrete
and continuous characteristics
in organisms eg ear lobes,
tongue-rolling and height.
Research polygenic
inheritance.
Combining genes from two parents
contributes to variation within a
species.
Single gene inheritance of characters
showing discrete variation where
measurements fall into distinct groups.
Education Scotland resources – Inheritance
SSERC teacher resources – Variation and
inheritance
BBC Knowledge and Learning revision guide
– Variation and inheritance
Research Mendel’s work on
peas.
Continuous variation shows a range of
values between a minimum and a
maximum.
Use Punnett squares to explain
inheritance.
BBC Learning Zone video clip – Dominant
Family trees can be used to identify the and recessive characteristics
phenotype and genotype of individuals.
Times Educational Supplement learner
activity – Genetic crosses worksheet
(Free registration with TES connect
required)
YouTube screencast – Continuous and
discontinuous variations
Times Educational Supplement learner
activity – Create a kid
(Free registration with TES connect
required)
Twig video clip – Mendel and inheritance
Twig video clip – Variation
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
6 The need for transport
(a) Plant transport systems
(i) Leaf structure to include
upper epidermis, palisade
mesophyll, spongy mesophyll,
vein, lower epidermis, guard
cells and stomata.
Set up stomatal models, use leaf
peels and microscopes to view
stomata.
SSERC teacher resources – The need for
transport
BBC Knowledge and Learning revision
guide – The need for transport
Twig video clip – Plant transport
(ii) Other parts of the plant
involved in water transport,
including root hairs and xylem
vessels. Water and minerals
are transported in xylem
vessels. Xylem vessels are
dead and contain lignin for
support. Water is required for
transporting materials and for
photosynthesis.
Investigate the germination of
seeds to show root hairs.
(iii) The process of
transpiration.
Transpiration experiments to
show water loss.
Transpiration is the loss of water
through leaves. Water is lost by
evaporation through stomata, whose
opening and closing is controlled by
guard cells, which are found in the leaf
epidermis. Mesophyll cells of the leaf
require water for photosynthesis.
(iv) Sugar is transported up
and down the plant in living
phloem cells. Structure of
phloem tissue.
Examine slides showing phloem
structure.
Details of transpiration pull and the
forces involved are not required.
16
Stain xylem vessels using
dye/celery. Examine slides
showing xylem and phloem
structure.
Xylem cells are lignified to withstand
the pressure changes as water moves
through the plant.
Biology Mad learner resources – Transport
in plants
NATIONAL 5 BIOLOGY RESOURCES GUIDE
(b) Animal transport and
exchange systems
(i) In mammals, nutrients,
oxygen and carbon dioxide
are transported in the blood.
National STEM Centre practical – Gas
exchange and transport in plants and
animals
Twig video clip – Why is blood red?
(ii) Pathway of oxygenated
and deoxygenated blood
through heart, lungs and body.
Heart structure to include right
and left atria and ventricles,
and location of valves. Blood
vessels to include aorta, vena
cava, pulmonary arteries and
veins.
Coronary arteries and their
function.
Investigate heart structure, eg
dissection, models, films.
Names of valves not required.
Ivy Rose diagram – The structure of the
heart
Twig video clip – Heart
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
(iii) Arteries have thick
muscular walls, a narrow
central channel and carry
blood under high pressure
away from the heart. Veins
carry blood under low
pressure, have thinner walls
and a wide channel. Veins
contain valves to prevent
backflow of blood and carry
blood towards the heart.
Capillaries form networks at
organs and tissues, are thin
walled and have a large
surface area, allowing
exchange of materials.
(iv) Red blood cells are
specialised by being
biconcave in shape, having no
nucleus and containing
haemoglobin. This allows
them to transport oxygen
efficiently in the form of
oxyhaemoglobin.
18
Use of diagrams/models to
illustrate the structure of
arteries, veins, capillaries and
blood cells.
InnerBody interactive resource – Crosssection of artery and vein
Medline Plus video clip – Red blood cell
production
Royal Society of Chemistry teacher
resource – Transport of oxygen in the blood
NATIONAL 5 BIOLOGY RESOURCES GUIDE
(v) Rings of cartilage keep
main airways open. Oxygen
and carbon dioxide are
exchanged through the
alveolar walls. Alveoli have a
large surface area, thin walls
and a good blood supply for
more efficient diffusion of
gases.
Mucus traps dirt and
microorganisms, and cilia
moves this up and away from
the lungs.
Investigate lungs, eg dissection,
model, films.
(vi) Food is moved through the
digestive system by
peristalsis. Villi in the small
intestine have a large surface
area, thin walls and a good
blood supply to aid absorption
of glucose and amino acids.
The lacteals absorb fatty acids
and glycerol (the products of
fat digestion).
Peristalsis model.
Model gut.
BBC Learning Zone video clip – Anatomy
and physiology of the lungs
Comparisons can be made
between cartilage in airways and
lignin in xylem.
Penn University animation – Peristalsis
19
NATIONAL 5 BIOLOGY RESOURCES GUIDE
7 Effects of lifestyle choices
on human transport and
exchange systems
Use health promotion and
reference materials to identify
how healthier lifestyle choices
can directly and indirectly
improve the physical and
mental health of an individual.
Take physiological
measurements. Investigate the
effect of moderate exercise on
these measurements.
Possible examples of lifestyle choices
could be high-fat or high-salt diet, lack
of exercise, use of tobacco or alcohol,
or high-stress experiences.
These directly and indirectly increase
the chances of fatty deposits in blood
vessels, blood clots, heart attacks,
strokes, diabetes and stress.
Education Scotland resources – Health and
disease
(Glow login required)
SSERC teacher resources – Effects of
lifestyle choices on human transport and
exchange systems
PhET interactive simulation – Eating and
exercise
Twig video clip – Balanced diet
Twig video clip – Alcohol and the brain
Twig video clip – What’s in a cigarette?
Twig video clip – Obesity
20
NATIONAL 5 BIOLOGY RESOURCES GUIDE
Life on Earth
Unit specification: http://bit.ly/1m3HxMQ
Mandatory course key areas
Suggested learning activities
Exemplification of key areas
Useful resources
1 Biodiversity and the
distribution of life
(a) Biotic and abiotic factors
affect biodiversity in an
ecosystem. Human
activities can also have an
impact on biodiversity.
Investigate a range of human
influences that affect national
and global environments, such
as pollution of air and water,
habitat destruction, eg by
deforestation (tropical rain
forest), desertification,
endangered species, overfishing
and lichen studies.
Various factors can increase or
decrease the biodiversity of an
ecosystem.
SSERC teacher resources – Biodiversity
and the distribution of life
(b) Competition for resources,
disease, food, grazing and
predation are biotic
factors. Light intensity,
moisture, pH and
temperature are abiotic
factors.
(c) Biomes are the various
regions of our planet as
distinguished by their
climate, fauna and flora.
Global distribution of
biomes can be influenced
by temperature and
rainfall.
BBC Knowledge and Learning revision
guide – Biodiversity and the distribution of
life
Twig video clip – What is an ecosystem?
Twig video clip – Oceans: The abyss
Interpret predator–prey
interaction graphs.
Analyse barn owl pellets from
Barn Owl Trust website.
Research a range of biomes, eg
marine, tundra, prairie, polar,
temperate deciduous forest and
tropical rain forest.
Twig video clip – Symbiosis: Parasitism
Barn Owl Trust learner activity – Barn owl
pellets
Names of individual biomes are not
required.
Missouri Botanical Garden learner
information – What’s it like where you live?
Enchanted Learning learning resources –
Biomes: Habitats
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
(d) An ecosystem consists of
all the organisms (the
community) living in a
particular habitat and the
non-living components
with which the organisms
interact.
Case studies/fieldwork on, for
example, Caledonian forests,
sea lochs, heather moorland,
tropical rainforests, Arctic tundra,
coral reefs and deserts.
(e) A niche is the role that an
organism plays within a
community. It includes the
use the organism makes
of the resources in its
ecosystem, including light,
temperature and nutrients,
and its interactions with
other organisms in the
community, including
competition, parasitism
and predation.
Investigate examples of niches
of Scottish wildlife, eg wildcat,
red squirrel, red grouse, Scottish
crossbill, brown trout, and
bracken.
Analyse data related to
distribution of barnacles on rocky
shores, native woodland and red
deer numbers, and distribution of
ptarmigan.
22
Red squirrel.org learner information – Red
squirrels in south Scotland
NATIONAL 5 BIOLOGY RESOURCES GUIDE
2 Energy in ecosystems
(a) Definitions of other
ecological terms, including
species, population,
producer, consumer,
herbivore, carnivore and
omnivore.
(b) In transfers from one level
to the next in a food chain,
90% of energy is lost as
heat, movement or
undigested materials. 10%
is used for growth.
(c) Definitions and
comparisons of pyramids
of biomass, energy and
numbers.
(d) Competition in
ecosystems.
Interspecific competition
occurs when individuals of
different species require
similar resources in an
ecosystem. Intraspecific
competition occurs when
individuals of the same
SSERC teacher resources – Energy in
ecosystems
BBC Knowledge and Learning revision
guide – Energy in ecosystems
Investigate examples of pyramid
of energy (as measured in
kJ/m2/year), pyramid of biomass
(g/m2) and pyramid of numbers.
Investigate irregular pyramids of
number, eg a tree as a producer,
presence of parasites.
Irregular shapes of pyramids of
numbers based on different body sizes
are represented as true pyramids of
energy and of biomass.
Examples of competition can include
the need for food, light and water.
Investigate interspecific
competition, eg red and grey
squirrels, brown and rainbow
trout.
Investigate intraspecific
competition, eg cress seedling
density, trees of the same
species growing close together,
feeding in grasshoppers,
territorial behaviour in birds, eg
robins, red grouse.
National STEM Centre interactive resource
– Energy transfer in ecosystems
Times Educational Supplement worksheet –
Pyramids of number and biomass
(TES Connect free registration required)
BBC Knowledge and Learning video clip –
Ecosystems and species diversity
Forestry Commission learner information –
Habitat use by red and grey squirrels
The Fuse School animation – Interspecific
and intraspecific interactions
Competition examples can include
food, light and water.
Times Educational Supplement learner
activity – Nitrogen cycle construction activity
(TES Connect free registration required)
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
species require the same
resources.
Intraspecific competition is
therefore more intense
than interspecific
competition.
(e) Nitrogen in ecosystems
Plant proteins are
produced using nitrogen
from nitrates. The roles of
nitrifying, denitrifying, root
nodule and free-living
nitrogen-fixing soil
bacteria.
Decomposers, such as
fungi and bacteria, convert
proteins and nitrogenous
wastes to ammonium
compounds These are
converted to nitrites and
then to nitrates. Animals
obtain the nitrogen
required to produce
protein by consuming
plants.
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YouTube animation – Nitrogen cycle
YouTube video clip – Nitrogen cycle 1
Construct simple flow diagrams
that illustrate the cyclical
activities in the nitrogen cycle.
Fertilisers supply nitrates to increase
yield.
NATIONAL 5 BIOLOGY RESOURCES GUIDE
3 Sampling techniques and
measurement of abiotic and
biotic factors
(a) Sampling of plants and
animals using techniques
including quadrats and
pitfall traps.
Techniques for biotic factors, eg
quadrats, transect, pitfall trap,
Tullgren funnel, pooters, tree
beating/sweep net, pond netting.
Representative sampling and adequate Education Garden learner resource –
replication.
Investigating an ecosystem
(b) Evaluation of limitations
and sources of error in the
use of quadrats and pitfall
traps.
BBC Knowledge and Learning revision
guide – Sampling techniques and
measurement of abiotic and biotic factors
(c) Using and constructing
paired-statement keys to
identify organisms.
(d) Measuring abiotic factors,
including light intensity,
temperature, pH and soil
moisture.
Possible sources of error
and how to minimise them.
(e) The effect of abiotic
factors on the distribution
of organisms.
SSERC teacher resources – Sampling
techniques and measurement of abiotic and
biotic factors
SAPS teacher resource – Making and using
keys
Techniques for abiotic factors:
temperature using thermometer
or temperature probes, light
using light meters, moisture
using moisture meters, pH using
pH meters or chemical test.
Use of probes linked to
appropriate data-logging
software.
YouTube video clip – Abiotic and biotic
factors
YouTube video clip – Measuring abiotic
components of the system
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
4 Adaptation, natural
selection and the evolution
of species
(a) A mutation is a random
change to genetic material.
Mutations may be neutral
or confer an advantage or
a disadvantage.
Mutations are
spontaneous and are the
only source of new alleles.
Environmental factors,
such as radiation, high
temperatures and some
chemicals, can increase
the rate of mutation.
(b) New allelles produced by
mutation allow plants and
animals to adapt to their
environment. These
adaptations can be
structural or behavioural.
Variation within a
population makes it
possible for a population to
evolve over time in
response to changing
environmental conditions.
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Research different types of
mutation: neutral, advantageous
or disadvantageous.
SSERC teacher resources – Adaptation,
natural selection and the evolution of
species
Research mutagenic agents.
BBC Knowledge and Learning revision
guide – Adaptation, natural selection and
the evolution of species
Twig mindmap – Adaptation
Twig mindmap – Extinction
Twig mindmap – Evolution of man
Investigate examples of
adaptations such as desert
mammals and plants, and
Galapagos finches.
An adaptation is an inherited
characteristic that makes an organism
well suited to survival in its
environment/niche.
Twig video clip – Adaptation
Twig video clip – Natural selection
Twig video clip – Mechanisms of evolution
Twig video clip – Evolution: the evidence
Twig video clip – Origin of species
NATIONAL 5 BIOLOGY RESOURCES GUIDE
(c) Species produce more
offspring than the
environment can sustain.
Natural selection or
survival of the fittest
occurs when there are
selection pressures. The
best-adapted individuals
survive to reproduce,
passing on the favourable
alleles that confer the
selective advantage.
Research consequences of overprescription of antibiotics.
Case study on insect resistance
to ‘built-in’ insecticides in GM
crops, eg bollworm moth in
cotton, European corn borer in
maize.
(d) Speciation occurs after
part of a population
becomes isolated by an
isolation barrier. This can
be geographical,
ecological or reproductive.
Mutations occur in each
sub-population. Natural
selection selects for
different mutations in each
group due to different
selection pressures. Each
sub-population evolves
until they become so
genetically different they
are two different species.
Examples of types of barriers are
Research Scottish examples of
isolation leading to speciation, eg acceptable, eg river, mountain.
Arran Whitebeam, St Kilda Wren,
Arctic Char.
Research examples of rapid
natural selection, eg MRSA,
insect resistance to GM crop
toxins.
BBC Learning Zone video clip – Natural
selection and survival of the fittest
PhET interactive simulation – Natural
selection
BBC Learning Zone video clip – Variation
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NATIONAL 5 BIOLOGY RESOURCES GUIDE
5 Human impact on the
environment
(a) Increasing human
population requires an
increased food yield.
Research GM crops,
monoculture and intensive
farming.
There are opportunities throughout this
topic for learners to investigate and
debate ethical issues.
(b) Fertilisers can leach into
fresh water, increasing
algal blooms. This reduces
light levels, killing aquatic
plants. These dead plants
as well as dead algae
become the food for
bacteria, which increase
greatly in number. The
bacteria use up large
quantities of oxygen,
reducing the oxygen
availability for other
organisms.
(c) Indicator species are
species that by their
presence or absence
indicate environmental
quality/levels of pollution.
(d) Pesticides sprayed onto
crops can accumulate in
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SSERC teacher resources – Human impact
on the environment
BBC Knowledge and Learning revision
guide – Human impact on the environment
Twig video clip – Algae
Survey local area for different
varieties of lichen and assess
local air quality.
Sample freshwater invertebrates
from local water courses/ponds
and assess water quality.
Freshwater Biological Association activities
– Collecting freshwater macroinvertebrate
samples
Twig video clip – Lichen indicator species
BBC GCSE Bitesize revision guide –
Bioaccumulation and eutrophication: Higher
tier
NATIONAL 5 BIOLOGY RESOURCES GUIDE
the bodies of organisms
over time. As they are
passed along food chains,
toxicity increases and can
reach lethal levels.
(e) Biological control may be
an alternative to the use of
pesticides. GM crops may
be an alternative to the
use of fertilisers.
Investigate bioaccumulation, eg
DDT.
James Hutton Institute pesticides game –
You choose the news
Royal Horticultural Society learner
information – Biological pest control
Investigate biological control, eg
using a virus (myxomatosis) to
kill rabbits, using ladybirds to kill
aphids and scale insects, using
caterpillar moth (Cactoblastis) to
kill cacti (Opuntia). Investigate
GM rice plants that take up
nitrogen more efficiently.
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