Introduction.
1. WHAT ARE THE CONDITIONS ON
EARTH THAT ALLOW LIFE TO DEVELOP?
Introduction.
2. WHAT DO ALL LIVING THINGS HAVE
IN COMMON?
Introduction.
3. WHAT ARE CELLS?
Introduction.
4. WHAT IS BIODIVERSITY?
1. THE EARTH: PLANET OF LIFE.
The Earth has certain characteristics that allow life to
develop:
1.1 THE PROPERTIES OF MINERALS.
Our
planet receives
enough
heat them.
from the
The properties
of minerals
help light
us toand
identify
The Sun
mostto
important
ones
are: temperatures.
maintain
mild
average
1. THE EARTH: PLANET OF LIFE.
The Earth has certain characteristics that allow life to
develop:
A
layer
of gases
protects the planet from harmful
1.1 THE
PROPERTIES
OF that
MINERALS.
ultraviolet
andof infrared
layer
alsoThe
helps
The properties
minerals radiation.
help us to This
identify
them.
mostto
important
onestemperatures,
are:
maintain
mild
thanks to the greenhouse
effect.
1. THE EARTH: PLANET OF LIFE.
The Earth has certain characteristics that allow life to
1.1 THE PROPERTIES OF MINERALS.
develop:
The properties of minerals help us to identify them. The most
Liquid
water.
important ones are:
1. THE EARTH: PLANET OF LIFE.
The Earth has certain characteristics that allow life to
develop:
1.1 THE PROPERTIES OF MINERALS.
Basic
elements,
which when
combined,
the most
basic
The properties
of minerals
help us
to identifyproduce
them. The
importantthat
ones living
are: things are made of.
compounds
1.1 THE ORIGIN OF LIFE.
CHEMICAL EVOLUTION THEORY.
This theory claims that life on Earth started from certain
1.1 THE PROPERTIES
OF MINERALS.
chemical
elements
found in the atmosphere. The Sun´s
The properties of minerals help us to identify them. The most
radiation
and electrical charges allowed these elements to
important ones are:
organise themselves into more complex molecules.
1.1 THE ORIGIN OF LIFE.
1.1 THE PROPERTIES
OF MINERALS.
CHEMICAL
EVOLUTION
THEORY.
The properties of minerals help us to identify them. The most
important ones are:
1.3 LEVELS OF ORGANISATION FOUND IN
MATTER.
1.1 THE PROPERTIES OF MINERALS.
The properties of minerals help us to identify them. The most
CELL
ORGANISATION IN A MULTICELLULAR ORGANISM.
important ones are:
http://www.bbc.co.uk/bitesize/ks3/scien
ce/organisms_behaviour_health/cells_s
ystems/activity/
Activities 1, 2, 4, 5. Page 7.
2.
BIOLEMENTS
AND
BIOMOLECULES.
The living matter that makes all organisms is made up of
1.1 THE PROPERTIES
OF MINERALS.
different
elements
found in nature. These elements are
The properties
of minerals help us to identify them. The most
called
BIOELEMENTS.
important ones are:
The most important are CARBON (C), HYDROGEN (H),
OXYGEN (O), and NITROGEN (N), because they make up
more than 99% of the mass of living things.
These elements join together to make BIOMOLECULES:
SUGARS: give energy to the organisms.
FATS: provide energy reserves.
PROTEINS: form muscles, hair…
NUCLEIC ACIDS: responsible for reproduction and heredity
(such as DNA).
1.1. WHAT ELEMENTS MAKE UP LIVING MATTER?.
1.1 THE PROPERTIES OF MINERALS.
The properties of minerals help us to identify them. The most
important ones are:
Activities 6, 8, 9.Page 8 and 9.
3. CELLS.
• Cells are microscopic.
• Cells are the functional and structural units
of all living things.
Plant cell
Animal cell
The Cell
The cell is the organisational unit of living things. Size
depends on the number of cells.
SINGLE-CELL ORGANISMS
•
Made of 1 cell
•
bacteria
protozoa
protozoa
Fungi: yeast
MULTICELLULAR ORGANISMS
alga
Made of many cells
•
•
1.
2.
3.
The
Cell
The cell is the functional
unit of living things.
It carries out the vital
functions:
NUTRITION
INTERACTION
REPRODUCTION
2.
3.1CELL
THETHEORY.
DISCOVER OF CELLS: CELL THEORY.
The
The British
British naturalist
naturalist Robert
Robert Hooke
Hooke was
was the
thefirst
firstperson
persontotoobserve
observecells
cells
in
in 1665.
1665. He
He analysed
analysed aa very
very thin
thin layer
layer of
of cork
cork tissue
tissueunder
underaasimple
simple
microscope.
He thought
thought they
they looked
looked like
likethe
therooms
roomswhere
wheremonks
monksslept
sleptin
microscope. He
in
a monastery
called
them
cells
latin,
celdillas).
a monastery
so so
hehe
called
them
cells
(in(in
latin,
celdillas).
3.1 THE DISCOVER OF CELLS: CELL THEORY.
In 1838, Schleiden, Schwann and Virchow proposed the first cell theory.
It can be summarised as:
All living things are formed of one or more cells.
A cell is the smallest and simplest living thing.
All cells come from other pre-existing cells.
Each of the cells that make up a multicellular organism can function
independiently, although they work together in a coordinated way.
3.2 Basic Cell Structure
• Plasma
membrane:
surrounds and
protects the cell.
Regulates what
enters and exits.
• Cytoplasm: Jellylike liquid contains
organelles.
• Nucleus: contains
the genetic
material.
• Organelles: have
different functions
“like little organs”
Activities 10 and 11. Page 11.
3.3 CELL TYPES.
PROKARYOTES: these do not have nucleus, so genetic
material is dispersed throughout the cytoplasm. They are
1.1 THEprimitive
PROPERTIES
OF such
MINERALS.
more
cells
as bacteria.
The properties of minerals help us to identify them. The most
EUKARYOTES:
these have a nucleus surrounded by a
important ones are:
membrane. They make up the rest of living things, including
animals and plants.
3.3.1 The endosymbiotic theory.
This theory was formulated by Lynn Margulis in 1967. It states
that
eukaryote
cells
1.1 THE
PROPERTIES
OForiginated
MINERALS. from the interaction of several
primitive
prokaryote
cellshelp
500usmillion
yearsthem.
ago.The
Margulis
The properties
of minerals
to identify
most
important
are:
proved
that ones
mitochondria
and chloroplasts originated from
primitive bacteria.
3.4 CELL SPECIALISATION.
1.1 THE
OF MINERALS.
All
cellsPROPERTIES
in living things
have a common characteristic: they
The properties
of minerals
us to identify
The m within the
have
the same
genetic help
material
(DNA).them.
However,
same organism, we can find many different types of cells.
dost important ones are:
Each of them is specialised to perform a particular job.
3.4 CELL SPECIALISATION.
Every type of cells uses one part of the information found in
the DNA, as if the cell was reading a chapter of an
1.1 THE PROPERTIES
OFThis
MINERALS.
instruction
manual.
is known as cell specialisation.
The properties of minerals help us to identify them. The m
MANY ADVANTAGES:
dost important ones are:
-Division of labour.
-Greater efficiency.
-Longevity.
Activities 12-16 Page 12 and 13.
4. VITAL FUNCTIONS.
2.1 NUTRITION
Why is nutrition important for
living things?
• To renew structures
• To maintain structures
• To get energy
• To carry out vital functions
-The process of
•
•
•
•
nutrition:
Take in substances
Transform
substances
Use substances
Expel waste matter
TYPES OF NUTRITION
AUTOTROPHIC
HETEROTROPHIC
• AUTOTROPHS: Plants make
organic matter from
inorganic compounds
• HETEROTROPHS: Eat living
things to obtain organic
matter.
Autotrophic nutrition: Plants
• Where does
photosynthesis take place?
In the leaves
• What provides energy?
Sunlight
• What collects sunlight?
Chlorophyll in the chloroplasts
Heterotrophic nutrition
•
•
•
•
Herbivores
Carnivores
Omnivores
Saprophytes
•
•
•
•
Eat plants
Eat the meat of other animals
Eat plants and animals
Eat decomposing organic matter
2.2 REPRODUCTION
ASEXUAL REPRODUCTION
•
•
Parent: 1 individual
Genetically identical
SEXUAL REPRODUCTION
•
•
Parent: 2 individuals
Genetically different
ASEXUAL REPRODUCTION: One individual
Single-cell organisms
Cell division produces identical
daughter cells.
Multicellular organisms
New individuals form from a fragment
SEXUAL REPRODUCTION: Genetically different
The reproductive system produces gametes (Sex cells)
Female gamete: Egg cell (ovum)
Zygote  Embryo (new individual)
Male gamete: Sperm cell
Where does the zygote develop in animals?
•The embryo develops inside the body.
•Young are born fully formed.
•The embryo develops in an egg.
•Young come out of the egg fully formed.
2.3 INTERACTION: ANIMALS
• To survive, living things must
interact with their environment.
• Sense organs collect information.
• A nervous system processes and
responds to information
2.3 INTERACTION: PLANTS
• Plants respond to stimuli in their
environment.
• Plants move their leaves to light.
• Plants open their flowers during
the day.
• Plants close their flowers at night.
Activities 16, 17(Becca), 18. Page 113.
21, 22, 23, 24. Page 115.