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Eolaíocht J.C.E.
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Cells
A living thing is called an organism, e.g. a dog is an organism, so is a daffodil. The characteristics of living things are:
Feeding
Movement
living things need food to get energy.
living things move either their whole body (animals) or parts of the body (plants).
Respiration
process by which organisms obtain their energy.
Sensitivity
organisms are able to respond to changes in their surroundings.
Excretion
living things get rid of wastes they have made in their bodies which would be harmful
Reproduction
living things are able to make more of their own kind..
Growth
living things get bigger.
There are many types of animals. They are important in agriculture as food; in medicine because they cause disease; in
the fishing industry and as a source of pleasure and recreation. There are many types of plants. Plants form the first link
in all food chains and are in important source of oxygen. A food chain is a feeding relationship between organisms.
Plants are important in agriculture, industry, medicine and as a source of pleasure, e.g. gardening. Plants differ from
animals in a number of ways, e.g. feeding and movement.
You must be able to classify living things into plants or animals, vertebrates or invertabrates. One of the investigations
involves going out into a habitat (say school field) and identifying five plants and five animals. The animals must be
further identified as vertabrates or invertabrates. Below are examples of keys used to identify the most common plants
found in grassland areas.
Vertabrates – animals that have back bones, e.g. rabbit, mouse, snake. Invertabrates – animals that do not have
backbones, e.g. earthwork, spider and woodlouse.
Binary key to plants of the school field (using leaves)
The following is a key to the most common plants of the school field, done in YES/NO style. To
identify a plant start a 1 answer the question and do what is says.
You must look at the whole plant for this key to work not separate leaves.
1. Leaves long, thin and flat,
like blades?
2. Leaves ribbed from stem to
tip?
3. Leaves long and thin?
Yes
No
Yes
No
Grass
Go to 2
Go to 3
Go to 4
Ribwort Plantain
Rat’s tail plantain
White Clover
Go to 5
Red Clover
Leaves rounded?
4. Leaves in 3 round parts?
5. Leaves in 3 round parts and
pointed at the top?
6. Small leaves on trailing
stems?
7. Hairy leaves?
Not hairy leaves?
Yes
No
Yes
Yes
No
Yes
Go to 7
Go to 8
Mouse-ear chickweed
Speedwell
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8. Leaves radiate for the centre
of the plant?
9. Round leaves?
Toothed leaves?
Yes
Go to 9
Daisy
Dandelion
Binary key to plants of the school field (using flowers)
You can identify the same plants using their flowers instead of leaves, obviously only when they are
flowering. Like with the leaves key start at 1, answer Yes or No and then do what it says. You must
look carefully.
1. Flowers very small and spiky –
no petals?
2. Flowers green, no petals, brown
stamens all round them?
3. Flowers short and rounded?
Flowers long like a rat’s tail?
4. Lots of petals arranged in a
rosette?
5. Petals all yellow?
Centre yellow, petals white?
6. Petals in a pom-pom shape and
white?
Yes
NO
YES
NO
7. Petals in a pom-pom shape and
purple?
8. Petals blue?
Petals white?
YES
NO
YES
NO
YES
NO
Grass
Go to 2
Go to 3
Go to 4
Ribwort plantain
Rat’s tail plantain
Go to 5
Go to 6
Dandelion
Daisy
White clover
Go to 7
Red clover
Go to 8
Speedwell
Mouse-ear chickweed
The two keys here help you to identify the 9 most common plants found on school fields. Of course
there are other plants to be found that this key does not identify. There is always the possibility that
you could not identify a plant because you did not use the key correctly.
All living things are made of cells which are the building
blocks of organisms. To study cells we use the light
microscope.
Eyepiece – allows you to view the object to be
magnified.
Objective lens – magnifies the specimen.
Course focus – lowers and raises the microscope to
focus the object.
Fine focus – allows accurate focusing at high power.
Stage – holds the glass slide in position.
Light source – bulb or mirror allow the object to be
illuminated.
eyepiece
Exp: Preparing a slide involves the following steps.
1. A drop of water is placed in the centre of a
clean dry slide.
2. A small piece of onion skin is peeled off and
placed flat on the slide in the water using a
forceps.
3. A drop of Iodine is put on the specimen.
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4.
5.
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A coverslip is lowered carefully at angle to cover the specimen and avoid air bubbles getting trapped.
The onion is examined first at low power and then at higher powers.
Below are diagrams of typical plant and animal cells.
All cells consist of the following parts:
Part
Cytoplasm
Function
contains dissolved substances, jelly-like
Cell Membrane
controls the entry and exit of substances in/out of the cell
Nucleus
controls the activities of the cell
Vacuoles
store food, large in plants small in animals
Cell Wall
give strength to the cell, plants only.
Chloroplasts
help plants make their food, plants only
Plant cells differ from animal cells in the following ways: large vacuoles, cell walls and chloroplasts. . Groups of similar
cells with a special function form a tissue. e.g. muscle. Several tissues grouped together form organs, e.g. heart. When
a group of organs work together to perform a function they make up a system, e.g. the circulatory system
Growth results from cells dividing.
Nutrition and Digestion
Food is needed for energy, growth, repair and protection against disease in the body. Food is made up of chemicals
called nutrients A food's energy value is how much energy that can be obtained from the food. A balanced diet consists
of the correct amounts of each type of food .
The main nutrients are:
Carbohydrates (sugars) are found in sugar rich foods, e.g. honey, sweets, and jam. They provide energy and fibre
(needed for muscles of the bowel to work properly [roughage]), They contain carbon, hydrogen and oxygen and are
made of single sugar units which can be joined together in long chains. Starch is a long chain sugar and glucose is
simple single sugar. e.g. starch in bread. To test a food for starch, add brown iodine solution. If it turns a blue/black
colour then starch is present.with water and roughage
Proteins e.g. fish contain carbon, nitrogen, oxygen, hydrogen and sometimes sulphur. They are found in fish and meat.
They contain chains of amino acids joined together. They are used for building new cells. e.g.muscle and bone.
Fats e.g. butter contain carbon, hydrogen and oxygen and are made of units of fatty acids and glycerol. They provide
heat insulation and energy.
Vitamins e.g. vitamin D in milk are chemicals needed in small amounts to protects us against disease. For example
vitamin A is needed for healthy eyes and skin and is got from carrots and cod-liver oil.
Minerals e.g. calcium for bones inorganic elements needed in small amounts for good health. Iron for example is
needed to carry oxygen in the blood. Calcium is needed for bone
Roughage is also required to keep the digestive system in tone got from green vegetables (fibre).
Food is needed for:
 energy
 growth and repair
 protection against disease
Exp. Testing a food for starch
1.
2.
3.
Add 2cm of starch solution or food to a test
tube.
Add 2-3 drops of iodine (red/brown)
If a blue/black colour is obtained. then starch is
present
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Exp. Testing for proteins
1.
2.
3.
4.
Add milk or dissolve the food to be tested to a test tube (2cm level)
Add an equal amount of sodium hydroxide
Add a few drops of copper sulphate solution.
If a violet colour is obtained then the food contains protein
1.
2.
3.
4.
Add 2cm3 of glucose or the food to a test tube.
Add 2cm3 of benedict's reagent (blue) to the test tube
Set up as shown in the diagram and heat.
If a red/orange colour is obtained then the food
contains glucose.
Test tube
With food
and benedict's
reagent
Exp. Testing for glucose.
Water bath
Exp. Testing for fats




Rub margarine or the food on brown paper.
Allow to dry and compare.
Put a drop of water on another piece of brown paper
A translucent spot indicates that fats are present
tongue
salivary
glands
The human digestive system has the following parts and functions.
Part
Mouth
Oesphagus
Stomach
Pancreas
Liver
Small intestine
Large intestine
Function
Physical (chewing) and chemical digestion
Mouth connected to the stomach
Churning and chemical digestion
Makes digestive enzymes
Makes bile for digestion of fats
Enymes digest food and use nutrients
absorbed into the blood
Excess water absorbed and gets rid of
undigested food.
oesophagus
stomach
liver
pancreas
gall bladder
large intestine
small intestine
rectum
Human Nutrition
INGESTION
taking of food into to the mouth
DIGESTION
break down of food into small soluble pieces
ABSORPTION
taking in of useful food into the bloodstream
ASSIMILATION
use of food for growth, repair and energy
EGESTION
removal of unused food from the body.
Stages of digestion
Results of digestion
Mouth Chewing and saliva
Stomach: Churning, gastric juices, acid to kill germs
Small intestines: digestive juices from pancreas
Carbohydrates  glucose
Proteins  amino acids
Fats  fatty acids and glycerol
A
B
An enzyme is a biological catalyst, it speeds up chemical reactions without
being used up
Exp. To show the action of an enzyme
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I odi ne
st ar ch
wat er
I odi ne
st ar ch
amyl ase
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1. In test tube A add starch solution, iodine, and tap water, this blue/black solution is the control
2. In test tube B add starch solution, iodine and saliva.
3. Leave both for several minutes at 37oC.
4. The mixture in tube B goes colourless
5. The mixture in tube A does not change.
6. The enzyme in saliva breaks down starch.
Note: Saliva contains the enzyme amylase
Exp: To show food contains energy (chemical energy)
1. Set up as shown in the diagram.
2. Record the temperature of the water at the start.
3. Light the cracker with a match and hold it under the test tube with a
tongs.
4. After a few minutes record the temperature of the water.
5. A rise in temperature in the water confirms chemical energy in the
food was converted into heat energy.
There are four types of tooth.
1 . Incisors these teeth are used for cutting and biting food.
2. Canines these teeth are used for tearing food.
3. Premolars these teeth are used to grind food.
4. Molars
these teeth are used to grind food.
Plaque and sugars cause tooth decay
TOOTH STRUCTURE
. Enamel a very hard substance which protects
the tooth.
. Dentine a bone-like substance, though softer
than enamel.
. Pulp cavity contains living cells, blood vessels
which supply the tooth with food and
oxygen, and nerves.
. Cement
protects the root from damage
Respiration and Breathing
During breathing, oxygen gas is taken into the body and carbon dioxide gas and water vapour are released. The human
breathing organs are the lungs. The diaphragm and intercostal muscles used in breathing. Inspiration is breathing in
and expiration is breathing out. Expired air contains more carbon dioxide than inspired air. This carbon dioxide is made
in the cells during respiration. Carbon dioxide turns lime water milky. Smoking can damage your breathing system by
damaging the bronchiole lining, reducing resistance to bronchitis and lung cancer, stunting the growth of a baby during
pregnancy and heart strain due to carbon monoxide gas in the smoke.
The bell jar with the balloons represents the breathing system, the balloons are the lungs, the rubber sheet acts like the
diaphragm. You must know how it works.
Insects have a system of air holes called spiracles to take in air. Gaseous exchange takes
place through the alveoli ( air sacs covered by a network of blood capillaries where
carbon dioxide diffuses out to the lungs and oxygen diffuses into the blood ).
Exp. To show expired air contains more carbon dioxide than inspired air.
1.
2.
3.
4.
5.
Set up two test tubes as shown in the diagram
Breath in through x in test tube A
Breath out through Y in test tube B
Repeat until the lime water in one tube goes milky
The lime water in B turns milky much quicker showing that exspired air contains
more carbon dioxide.
Respiration is the release of energy from food:
Glucose + Oxygen  Carbon dioxide + Water + Energy
C6H12O6 + 6O2  6CO2 + 6H2O +energy.
Breathing experiment
Exp. To show carbon dioxide is produced during respiration.
Set up the apparatus as shown in the diagram. See diagram 1.
The lime water in A goes milky
This is because the woodlice are respiring and carbon dioxide turns lime water milky
Exp. To show heat is produced during respiration.
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Fill two flasks one with germinating peas and a second (a control) with dead boiled pea seeds. Seal both with cotton
wool and put a thermometer in each.
Record the temperature of both flasks every day for one week.
The temperature rises sharply in the flask with the germinating peas which shows
heat is produced during respiration.
Diagram 1
The Circulatory System and Excretion
Arteries carry blood away from the heart. Veins carry blood to the heart.
Capillaries link arteries to veins. Arteries have thick walls, no valves, blood at
high pressure, are deep in the body and have a small lumen. Veins have thin
walls, valves to prevent backflow of blood, blood at low pressure, are near the
surface and have a large lumen.
The functions of the blood are: (a) transport of food oxygen to body cells,
carbon dioxide to the lungs and excretory products to the kidneys, (b) defence
against disease with white blood cells destroying bacteria or producing
antibodies to kill bacteria and blood clotting to stop blood loss and stop invading germs.
The blood is made up of blood plasma with red blood cells to carry oxygen, white blood cells to fight germs, and
platelets to help blood to clot. Substances pass in/out of the blood through the thin walls of the capillaries.
How the heart works
1. Blood from the body goes in to the right atrium via the vena cave
2.
At the same time blood from the lungs fills the left atrium.
3.
The atria contract, the bicuspid and tricuspid valves open and the ventricles fill up.
4.
The ventricles contract, the tricuspid and bicuspid valves close, the semi-lunar valves open and blood is pumped
into the arteries.
5.
Blood from the right ventricle goes to the lungs via the pulmonary vein and blood from the left ventricle goes
around the body via the aorta.
Heart disease is caused by smoking, too much fat, stress and lack of exercise.
Heart rate is increased by exercise, escitement, anxiety and smoking. Heart is decreased by
rest, clinical shock and certain drugs.
The average human pulse rate (heartbeat) is 72 beats per minuter. This value depends on
our fitness and age.
Excretion is the removal of waste products made in the body. The organs
Excretion of excretion are (a) the lungs getting rid of carbon dioxide and water, (b)
the kidneys getting rid of urine and (c) the skin losing water and salts as
sweat.
Renal artery : blood with wastes to kidneys
Renal vein : clean blood back to heart
Kidneys:
filter blood remove waste
Ureter:
carries urine to bladder
Bladder:
stores urine
Urethra:
carries urine out of the body
patella
femur
The Skeleton and Muscles
synovial fluid
synovial
membrane
The functions of the human skeleton are: a) support, b)
movement and c) protection.
A joint is formed where two or more bones meet. There
are two types of joints: a) fused joints, e.g. bones of the
skull and b) synovial joints, e.g. (i) ball and socket joint
capsule
cartilage
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tibia
synovial joint at the knee
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(hip), (ii) hinge joint (elbow) and (iii) pivot joint (base of skull). Ligaments connect bone to bone and tendons connect
muscle to bone. Leg and arm muscles work as antagonistic pairs i.e. when one muscle contracts the other relaxes, e.g.
the triceps and biceps of the arm. If a bone is left in dilute HCl overnight it becomes flexible and rubbery. This is
because the mineral content such as calcium has been removed. In a synovial joint the bone are protected from rubbing
off each other by a pad of cartilage (gristle) and a lubricating liquid call synovial fluid.
Sensitivity and Co-ordination
Sensitivity is the ability to respond to a stimulus, e.g. light. The five main sense organs the skin, nose, ears, eyes and
tongue. Co-ordination is controlled by the nervous system and the endocrine system. The nervous system is made up
of the brain, spinal cord and nerves (which are bundles of nerve cells called neurons).
nerve impulses
motor end
plates
axon
muscles fibres
cell body
Neuron
dendrites
Sensory neurons carry impulses to the brain and spinal cord. Motor neurons carry impulses from the brain and spinal
cord. The endocrine system is made up of a number of glands which produce hormones. Hormones are chemical
messengers and are carried in the bloodstream from the gland to where they are needed e.g. insulin is produced in the
pancreas and is needed to control the level of sugars in the blood. A person who cannot produce insulin has the disease
diabetes.
Eye parts and their function
muscle to move
the eye
aqueous humour
watery filling in front of eye
Vitreous
humour
jelly like filling of the eye
Yellow spot
area of sharpest vision.
Optic nerve
carries messages to the brain
Blind spot
area where optic nerve leaves the eye.
cornea
transparent protection for eye
pupil
hole through which light gets to the lens
lens
focuses light on the retina
iris
coloured part of eye. It controls the size of the
pupil
the image is focused.. This is the light sensitive
area.
sclera
iris
lens
retina
aqueous humour
vitreous humour
suspensory
ligaments
choroid
blind spot
cilliary muscle
retina
optic nerve
Human Reproduction and Genetics
Sexual reproduction involves the meeting of sex cells (gametes),
the male sex cell (sperm) and the female sex cell (egg). Sperm are
made in the testes and eggs are made in the ovary. The fusion
(joining) of an egg and sperm is known as fertilisation.
Fertilisation usually occurs in the Fallopian tube . If an egg is not
fertilised the lining of the womb breaks down and is shed during
menstruation. If an egg is fertilised a women becomes pregnant
and a baby begins to develop. This takes about 40 weeks. The
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Ovary
Oviduct Uterus (Womb)
(fallopian tube)
Cervix
Vagina
Female Reproductive Organs
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fertile period is the time in a woman's menstrual cycle when fertilisation can occur. The placenta is the link between
the mother's bloodstream and that of the developing baby. Implantation is when the embryo attaches itself to the wall of
the womb. Ovulation is when an egg is released from an ovary
Genetics is the study of inheritance. Organisms have many characteristics; certain characteristics are inherited, e.g. eye
colour, others, due to the environment, are not inherited, e.g. ability to ride a bicycle. Chromosomes are thread-like
structures, found in the nucleus of a cell. Humans have 46 chomosomes in every body cell except sperm or egg cells
which have 23 chormosomes. When the egg and the sperm join together during fertilisation giving 46 chormosomes in
the fertilised egg which develops into a baby. Genes are chemicals, found on chromosomes, which pass on information.
They are responsible for making proteins. A dominant characteristic is who which occurs most, e.g. dark hair or
freckles and a recessive characteristic is one which occurs least, e.g. blond hair or no freckles.
Plant Biology
Flowering plants consist of four main parts: (a) Root for anchorage, absorption of water and minerals and food storage,
(b) Stem for transport of food, water and minerals, and support of flowers and leaves, (c) Leaf for photosynthesis,
water loss and exchange of gases, (d) Flower for reproduction. Plants can be identified by their flowers and leaves.
Nutrition
Photosynthesis is the process by which plants make their own food. Photosynthesis is carried out in all
green parts of a plant; e.g. leaves and stems. The factors necessary for photosynthesis are carbon dioxide,
water, light and chlorophyll. Carbon dioxide enters the plant through the leaf. Water is absorbed from the soil through
the roots. The energy comes from sunlight. Chlorophyll is the green colour found in the chloroplasts of the leaf. The
word equation for photosynthesis is carbon dioxide + water + light + chlorophyll  glucose + oxygen. The chemical
equation (honours only) for
photosynthesis is: C02 + H20 + Light + Chlorophyll  C6H1206 + O2 Note: this equation is the reverse of respiration.
Plants need certain minerals for healthy growth. These minerals are absorbed by the plant roots from the soil. They
include nitrate for proteins, phosphate for cell membranes and potassium ions for hardiness of the plant.
Exp. To test a leaf for starch
1. Set up a water bath i.e. a beaker of water over a bunsen burner.
2. Place a green leaf in boiling water for 30 seconds to soften and kill it.
3.
Put the leaf in alcohol in a test tube and place the tube in a water bath
4.
The alcohol removes all the chlorophyll.
5.
Remove the creamy white leaf and cover it with iodine solution.
6.
If the leaf turns blue/black then starch is present, therefore photosynthesis has taken place.
The glucose made in photosynthesis is used to get energy in respiration, stored as starch food reserves or converted into
proteins with nitrates from the soil.
Transport
Plants take in water through their roots. Transpiration is the loss of water vapour from the plant.
Transpiration is needed to get water for photosynthesis, get mineral salts and cool the plant down.
Transpiration occurs through the stomata. The transpiration stream causes water and mineral salts to be drawn up the
plant from the roots to the leaves. Factors which affect the rate of transpiration are (i) light intensity; (ii) humidity, (iii)
air movement (iv) available soil water; (v) the presence of a cuticle. Water and minerals are carried in the xylem. Food
is carried in the phloem.
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Exp. To show water absorption of plant roots
1. Place the roots of a seedling in a test tube of water and cover the water surface with oil. A
2. Fill a test tube with the same amount of water and cover the surface with oil. (control). B
3.
Mark the water level in both .
4.
Leave for 5-6 days.
5.
The water level goes down in A but remains the same in B.
6.
The roots absorb water for the plant
Exp. To show the pathway of water movement in a plant.
1. Place the roots of a seedling in red ink solution.
2. Leave for several days.
3.
The red dye can be seen in the veins of the leaves and stem.
4.
Examine a T.S. of the stem under a microscope.
5.
The red dye is found in certain cells only.
6.
Water travels through the xylem.
Exp. To show a pot plant transpires.
1. Cover a well watered pot plant with a plastic bag and seal at the base of the stem.
2. Leave the plant in warm light for several hours.
3.
A lot of liquid condenses on the inside of the bag.
4.
The liquid turns cobalt chloride paper blue thus proving water was given out.
Responsiveness in plants
Sensitivity is the ability to respond to a stimulus. A tropism is a response of plant to a
stimulus. Phototropism is the growth response of a plant to light. Shoots grow towards light
whilst roots grow away from light. Geotropism is the growth response of a plant to gravity. Roots grow down in
response to gravity whilst shoots grow away from
gravity.
Exp. To demonstrate phototropism in plants.
1.
2.
Fill 3 petri dishes with wet cotton wool and cress seeds.
Place one completely in the dark. A
3.
Place one in a box exposed to light from above. B
4.
Place the third in a box with a window on one side. C
5.
Leave for a week. In A the seedlings are yellow and straggly growth.
6.
In B the seedling grow straight upwards.
7.
In C the seedlings grow towards the window (light).
8.
This shows plant shoots grow towards light.
Exp. To show geotropism in plants.
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1.
2.
Set up as show in the diagram.
Soak the filter paper with water
3.
Leave in a dark place for one week.
4.
No matter what position the seeds were in the roots grew downwards
and the shoots grew upwards,
Reproduction in Plants
Reproduction is the ability to produce new individual. Sexual reproduction in plants involves the joining of the male
pollen with the female egg to form a zygote, This is called fertilisation .
Parts of the flower
Part
Function
Stamen (male part)
Anther/filament
produce pollen
Carpel (female part)
stigma/style/ ovary
produce egg.
Sepal
protect young flower
Petal
attract insects
Nectary
produce nectar
Pollination is the transfer of pollen from the stamen of one flower to the stigma of another flower. The fertilised egg
becomes a seed and the ovary becomes a fruit e.g. the pips in a apple are seed and the apple is the fruit. Seeds are
dispersed in four ways: (a) wind e.g. dandelion, (b) animal, e.g. raspberry, (c) self e.g. peas and (d) water e.g. water lily.
Germination is the growth of a seed into a new plant.
Flower Part
Wind pollinated
Insect pollinated
Petals
green or absent
brightly coloured
Stamens
hang outside the flower
inside the flower
Stigma
Feathery, long, hang outside
Small
Nectaries
No nectar or scent
produce nectar and scent
Exp. To investigate the conditions necessary for germination
1. Set up four test tubes
2. In A put moist cotton wool and seeds
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3.
In B put dry cotton wool, seeds and anhydrous calcium chloride.
4.
In C put seeds, cold boiled water and oil on top.
5.
In D put moist cotton wool and seeds, place in the fridge.
6.
Leave the remaining test tubes for a week in a warm place.
results
A: seed germinate, moisture warmth and oxygen
B: no germination, no moisture
C: no germination, no oxygen
D: no germination, too cold
The conditions necessary for germination are: (a) moisture, (b) oxygen and (c) a suitable temperature.
Stages of Germination
When a seed begins to germinate the testa splits and the radicle emerges, then the plumule emerges, then the plumule
straightens and root hairs begin to develop and finally leaves emerge and the seed withers away.
Ecology
The environment is the surroundings of a plant or animal. A study of the interrelationships between plants and animals
in their environment is called Ecology. The habitat of an organism is the place where it lives. A feeding relationship
between organisms is called a food chain e.g. oak leaf  caterpillar  robin. Green plants are the producers as they
make their own food. Consumers cannot make their own food and must eat plants or animals to survive. The types of
consumers are herbivores, which eat plants only e.g. rabbit, carnivores, which eat other animals only e.g. fox, and
decomposers, which eat dead animal and plant matter e.g. dung beetle. The position an organism occupies in a food
chain is known as its trophic level. Two or more interconnecting food chains make a food web. Competition is the way
in which plants and animals compete with each other for resources in their habitat e.g. plants compete for food, moisture
and space, animals compete for food, shelter, territory and mates.
Conservation is the wise use of the environment. Humans are endangering the environment in many ways, e.g. over
fishing, drainage of wetland habitats, litter, overuse of fertilisers, sewage, chemical sprays, and not recycling everything
we use. Pollution means contaminating the environment so as to upset the balance of nature. Water pollution examples
are, sewage and slurry, excess fertiliser going into lakes and rivers, oil. Air pollution is caused by smoke, sulphur
dioxide and carbon monoxide.
Studying Habitats
1.
2.
Make a map of the habitat.
Record the environmental factors affecting the habitat
3.
Make a list of all the types of plant and animal present.
4.
Estimate the numbers of plants and animals
5.
Analyse the information collected, charts, diagrams etc.
Environmental factors affecting a habitat
 Soil factors, pH, mineral, humus and moisture content.
 Weather factors, light intensity, rainfall, temperature, wind and humidity.
 Physical factors, topography, aspect and altitude.
 Biotic factors, competition between organisms.
Methods of identifying and collecting plants and animals
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Eolaíocht J.C.E.
D.Mac an Aircinn
 Wildflower guides can be used to identify plants. Plants are easily collected as they do not move.
 For animals look under stones, on walls, take water from streams and pools. Plankton nets , butterfly nets, and
sweep nets for insects.
 Beating tray for collecting small animals and insects living in trees.
 A pooter for small animals and insects.
 Pitfall traps for small animals that walk over the ground, cryptozoic traps for nocturnal animals e.g. woodlice and
mammal traps for small mammals such as mice.
 Tullgren funnel for extracting small organisms from the soil.
Estimating plant numbers
Quadrat Method:
 The quadrat is thrown at random and all the
plants in it are identified and listed.
 This is repeated 10 times and each plant which
occurs is recorded.
 The number of times a plant occurs is multiplied
Transect Method:
 A line transect is a rope with knots every 0.5 m say
which is laid across a habitat from a shaded area to an
exposed area, always across a changing area.

The plant at each knot (station) is identified and its
Mic
height and name are recorded This gives us
r
information on how the vegetation changes from one
o
part of a habitat to another.
by 5 to give the frequency of the plant as
percentage.
 The results are charted on a bar chart.
Organisms
 If a plant was found 12 time then its frequency is
60%
Microbiology is the study of very small organisms e.g. viruses bacteria and fungi. Viruses cause many diseases such as
measles and the common cold. Bacteria are found practically everywhere and can be grown in the laboratory on a
suitable food source e.g. nutrient agar. They are on our skin, inside us and in the air around us. Removal of all life from
something is called Sterilisation. Heat is one of the best methods of sterilisation. Some bacteria are useful, e.g. in the
food industry, antibiotics, silage, nitrogen fixation. Others are harmful causing illness, e.g. sore throats, food spoilage,
tooth decay and crop diseases. Some fungi are useful to humans. e.g. In the brewing and baking industries, antibiotics
and as a food source. Other fungi cause disease, e.g. ringworm; athlete's foot, plant diseases e.g. Dutch elm, poisonous
to eat and cause food spoilage. Antibiotics are chemicals produced by micro-organisms which can kill bacteria fungi
(not viruses). A vaccine is a small dose of a harmful microbe, which when placed in the body helps prevent disease.
Exp. To show the presence of bacteria.
1. Get two sterile agar plates A and B.
2. Expose A to the air for 10 minutes
3.
Leave dish B untouched as a control
4.
Incubate upside down at 25oC for 48 hrs.
5.
Examine the plates for bacteria and fungi.
6.
The bacteria colonies appear like spots of paint the fungi like fuzzy hairy patches.
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Eolaíocht J.C.E.
D.Mac an Aircinn
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