Transcript 7A Cells - Watford Grammar School for Boys Intranet

7A Cells
7A Cells
Signs of life
Building blocks of life
Building living things
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7A Cells
Signs of life
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7A Signs of life - Life on Mars?
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7A Signs of life - Life on Mars?
Serious efforts to discover life on other planets
have been going on for many years.
If extra-terrestrial beings really were discovered
how would scientists decide if they were alive?
A simple way of sorting everything on our planet
is to divide it into 2 groups
– living things and non-living things.
But can you tell the difference?
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7A Signs of life - Staying alive
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7A Signs of life – The meaning of life
There are seven essential life processes.
To remember these processes meet
our little blue woman MS. R. NERG…
What do all the letters in her name stand for?
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7A Signs of life - The meaning of life
M = MOVEMENT
Living things are able to move about.
Animals move from place to place.
Plants move by responding to light.
S = SENSITIVITY
Living things notice and react to changes in
their surroundings. They can respond to light,
heat, sound, taste, sight or touch.
R = RESPIRATION
Living things need energy to carry out the
functions that keep them alive. Respiration is
the process by which food is turned into energy.
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7A Signs of life - The meaning of life
N = NUTRITION
Living things need to take in food so that
respiration can occur. Nutrients in food help
to build, maintain and repair the organism.
E = EXCRETION
Living things have to get rid of unwanted
waste products.
R = REPRODUCTION
Living things produce offspring.
Reproduction continues the survival of each
species.
G = GROWTH
Living things grow, increasing in size and
complexity.
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7A Signs of life - The meaning of life
All living things carry out the seven essential life
processes.
M = Movement
S = Sensitivity
R = Respiration
N = Nutrition
E = Excretion
R = Reproduction
G = Growth
But what are living things made of?
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7A Cells
Building blocks of life
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7A Building blocks of life - Cell fact file
Living things are made up of tiny building blocks
called cells.
Each cell breathes, takes in food, gets rid of
wastes, grows, reproduces and dies.
A living thing can be just one cell or
millions of cells.
Big living things don’t have bigger cells
they just have more cells.
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7A Building blocks of life - Cell fact file
Amazingly, the human body has more than
10,000,000,000,000 (that’s 10 million million) cells!
Think about the size of your little toe.
It has about 2 or 3 thousand million cells!
That’s a lot of cells to make one toe,
so cells must be very, very, very small.
How do we know about cells if they are so small?
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7A Building blocks of life - Cell-ebrate the Microscope
Cells could not have been discovered
without the invention of the microscope.
“micro-” means” small”,
“-scope” means “looking at”.
A microscope allows us to look at very small things by
making them seem bigger. It magnifies tiny details
and makes them visible to the human eye.
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7A Building blocks of life - Cell-ebrate the Microscope
Cell-ebrate the microscope!
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7A Building blocks of life - Cell-ebrate the microscope
Every living thing – from an elephant to an ant,
from a tree to a daisy, from your left toe to
right earlobe – is made of cells.
Microscopes allow us to magnify cells revealing
their shape and structure.
This is a typical animal cell.
Do animal and plant cells look the same?
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7A Building blocks of life - Typical animal cell
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7A Building blocks of life - Typical plant cell
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7A Building blocks of life - Typical cells
Compare a typical animal cell and a typical plant cell.
Which parts of a plant cell are the same as an animal cell?
Which parts of a plant cell are not found in an animal cell?
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7A Cells
Building living things
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7A Building living things - Cells working together
What could you do if you were one cell?
Not much! You’d be a blob, with lots of pieces floating
around inside of you!
Keeping you alive is a big job. So your body is made
of millions of cells that have to be very organised.
Your body has organs that each carry out specific
jobs to keep you alive.
How many organs can you name?
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7A Building living things - Cells, tissues and organs
Identify the organs
labelled in the
eye
diagram.
skin
brain
ear
tongue
heart
lung
stomach
intestines
muscle
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7A Building living things - Cells, tissues and organs
Similar
Cells
are
cells
the that
building
do the
blocks
sameofjob
all
livingtogether
organisms.
to
Different
tissues
work
together
to work
make
an organ.
make tissue.
muscle cell
stomach
Different cells do different
jobs.
muscle
tissue
How
do tissue,
the millions
cells and
in your
body
workmake
together?
Muscle
nerveoftissue
blood
tissue
Muscle
cells make muscle tissue.
up the stomach.
What
type
of cells
are nerve
tissue
and blood
tissue
Organs
work
together
to make
an organ
system.
made from?
What organ system is the stomach part of?
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7A Building living things - Different cells for different jobs
Name a cell that
would be suitable
for each job.
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7A Building living things - How are new cells made?
All living things (including you and your teacher)
started as one tiny cell!
So where do all the cells come from?
Living things grow and repair themselves by an
amazing process called cell division.
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7A Building living things - How are new cells made?
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