7D Variation and classification
7D
Variation and
classification
Variation
Classification
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7D Variation and classification
Variation
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7D Variation – What is a species?
How many different types of living things are there
on Earth?
Scientists have identified almost 2 million different
types of living things.
Many more are yet to be discovered and scientists
estimate there could be up to 30 million different
types of living things!
Each different type of living thing is called a species.
Do members of the same species look exactly the same?
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7D Variation – Similar but different
A species is a group of living things with similar features.
Members of the same species can breed together
to produce fertile offspring.
All dogs are members of the same species but
they don't all look the same.
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7D Variation – Similar but different
Name 5 ways in which these dogs are similar.
Name 5 ways in which these dogs are different.
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7D Variation – What is variation?
Differences between members of the same species
are called variation.
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7D Variation – What is variation?
Give 5 examples of variation between humans.
What do you think causes variation?
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7D Variation – Causes of variation
Variation is caused by environmental or inherited factors.
Which type of variation is described by each definition?
A
inherited
This type of variation is
passed on in genes from
parent to offspring.
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B
environmental
This type of variation is
influenced by living
conditions and
surroundings.
7D Variation – Inherited factors
Inherited variation is caused
by the genes passed on from
parent to offspring.
In humans, inherited characteristics include the colour of
your eyes and hair.
Blood group is another example of inherited variation.
Your blood group will never change.
How many inherited characteristics can you think of?
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7D Variation – Environmental factors
Environmental variation is caused by differences in
living conditions and surroundings.
Climate and food supply are environmental factors that
influence all living things.
How might these factors cause variation?
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7D Variation – Environmental factors
For humans, environmental factors can influence the way
you look, speak and how you do things.
Your country and culture can cause environmental variation.
A Buddhist monk shaves
off all his hair because it is
part of his culture.
A Sikh grows his hair
long because it part of
his culture.
Name another way in which their environment
may have influenced these people.
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7D Variation – Inherited factors
Some inherited characteristics can be affected by
environmental factors.
Some musicians are born with natural
talent for music, but they have to practise to
to play really well.
Can you think of other inherited
characteristics that might be affected
by environmental factors?
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7D Variation – Inherited, environmental or both?
Decide which characteristics are inherited, environmental or both?
inherited environmental both
blood group
wears glasses
tongue rolling
freckles
speaks Italian
dyed pink hair
natural eye colour
height
Welsh accent
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7D Variation – Variation in plants
Are plants also affected by environmental conditions?
Sunflowers were grown in a warm environment under
different conditions of soil, water and sunlight.
Experiment
Fertile soil
1
2
3
4
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Water
Sunlight
Results
7D Variation – Variation in plants
Experiment
Fertile soil
Water
Sunlight
Results
1
2
3
4
What are the best conditions for growth of the sunflowers?
How might sunflower growth be affected if grown in a
cooler environment?
How could you test your prediction?
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7D Variation – True or false?
True or False
1. Variation
6.
5.
4.
The
Identical
Only
Members
The
ability
ability
living
twins
caused
of
to
to
things
the
roll
roll
are
same
your
by
your
that
more
environmental
tongue
are
tongue
species
alike
members
is
than
isall
an
anlook
most
inherited
factors
inherited
of exactly
the
butcan
same
even
characteristic.
characteristic.
the
bespecies
they
passed
same.
are
2.
3.
Variation
only
occurs
in
animals.
not
from
canexactly
breed
parenttogether
the
to offspring.
same.
to produce fertile offspring.
FALSE!
Variation
occurs
inthis
all type
living
TRUE! Have
Members
you inherited
of the same
species
ofthings,
variation?
have similar
including
plants.
TRUE!
FALSE!
Only
features
inherited
twins
but
do
inherit
characteristics
notbelook
the
same
exactly
are
features
the
passed
same.from
TRUE! Identical
Some
species
can
interbred.
but
theyis
to
have
different
fingerprints.
Aparent
mule
aoffspring.
cross
between
a horse and a donkey,
but it cannot produce fertile offspring.
Click on the
box to start the quiz
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7D Variation and classification
Classification
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7D Classification – Sorting living things
Living things can be grouped based on the
similarities and differences between them.
For example, all cats are similar to other cats,
but very different from caterpillars.
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7D Classification – Sorting living things
Sorting similar living things into groups is called classification.
What two groups would you classify these living things into?
starfish
wheat
polar bear
horse
chestnut tree
hamster
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daisies
butterfly
7D Classification – Kingdoms
Classification starts by sorting all living things into
5 main groups called kingdoms.
Living things
animals
fungi
plants
Prokaryotes
Protoctista
Most living things belong to the animal kingdom or
the plant kingdom.
Can different plants and animals be sorted into groups?
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7D Classification – Classifying animals
There are lots of questions you might ask to continue
classifying animals into smaller groups.
Is it bigger
than a dog?
How many legs
does it have?
Does it have
a backbone?
Where does it live?
Is it covered in
feathers?
What other questions could you ask to classify animals?
Which of these questions is the most important when
classifying animals?
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7D Classification - Vertebrates and invertebrates
The most important question to ask when classifying
animals is: Does it have a backbone?
So the animal kingdom is divided into 2 groups:
animal kingdom
animals with
backbones
animals without
backbones
fish
snail
bird
elephant
spider
crab
worm
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7D Classification - Vertebrates and invertebrates
animal kingdom
animals with
backbones
animals without
backbones
These two groups of animals are given special names:
invertebrates
vertebrates
Which name describes which group of animals?
Which group do humans belong to?
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7D Classification - Vertebrates
Vertebrates are classified into 5 groups.
Complete the table of features for each type of vertebrate.
mammals
birds
reptiles
amphibians
fish
body covering
hairy or
furry skin
feathers
tough skin
with scales
soft, moist skin
(no scales)
scales
how it
breathes
lungs
lungs
lungs
lungs
gills
where it lives
mostly on
land
on land
mostly on
land
on land and
in water
in water
how offspring
are produced
most young
born alive
lay eggs
lay eggs
lay eggs
(in water)
lay eggs
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7D Classification – Naming living things
Classification divides each kingdom of living things into
smaller and smaller groups.
Kingdom
Animal
Plant
Phylum
Chordata
Vascular
Class
Mammal
Order
Family
Carnivore
Canine
Monocotyledon
Lilidae
Genus
Canis
Narcissus
Species
familiaris
pseudonarcissus
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Liliaceae
7D Classification – Naming living things
Scientists give all living things a special name with two parts:
- the first part is the Genus name
- the second part is species name
Kingdom
Animal
Plant
Phylum
Chordata
Vascular
Class
Mammal
Monocotyledon
Order
Carnivore
Lilidae
Family
Canine
Liliaceae
Genus
Canis
Narcissus
Species
familiaris
pseudonarcissus
The scientific name for a domestic dog is Canis familiaris.
What is the scientific name for a daffodil?
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7D Classification – Why is classification important?
Living things have different “common” names
in different languages.
English
goldfish
French
poisson rouge
Spanish
pez de colores
German
Goldfisch
Italian
pesce rosso
scientific name
Carassius auratus
All living things have the same scientific name
in any language.
How does scientific classification make it easier for
international scientists to talk about living things?
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7D Classification – Quiz
1. Sorting things into groups is called…
a) magnification.
b) fabrication.
c) classification.
2. The largest type of group of living things is called a…
a) kingdom.
b) queendom.
c) princedom.
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7D Classification – Quiz
3. The smallest type of group of living things is called a…
a) vertebrate.
b) species.
c) fungus.
4. Why do scientists classify living things into groups?
a) To list living things in alphabetical order.
b) To see how living things are related to each other.
c) To arrange living things in order of size.
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7D Classification – Quiz
5. Animals are divided into two main groups called…
a) cats and dogs.
b) fish and mammals.
c) vertebrates and invertebrates.
6. What do vertebrates have in common?
a) They all walk backwards.
b) They all have a backpack.
c) They all have a backbone.
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7D Classification – Quiz
7. What is the body covering on reptiles?
a) Soft, moist skin with no scales.
b) Soft, moist skin with scales.
c) Tough, hard skin with scales.
8. Dolphins live in water and give birth to live young that
feed off their mother's milk. What kind of vertebrate
are dolphins?
a) Mammals.
b) Fish.
c) Amphibians.
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7D Classification – Quiz
9. The scientific name for a domestic cat is…
a) Tiddles.
b) Moggius domesticus.
c) Felis catus.
10. The first part of the scientific naming system is…
a) the Genius.
b) the Genus.
c) the Genie.
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