Download - © OUP: To be used solely in purchasers school or college 7A Cells Signs of life Building blocks of life Building living things 7A Cells.

© OUP: To be used solely in purchaser’s school or college

7A Cells

Signs of life

Building blocks of life

Building living things

7A Cells


Signs of life

7A Cells


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?

7A Signs of life - Life on Mars?


7A Signs of life - Staying alive


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?

7A Signs of life – The meaning of life


7A Signs of life - The meaning of life

S = SENSITIVITYLiving things notice and react to changes intheir surroundings. They can respond to light, heat, sound, taste, sight or touch.

R = RESPIRATIONLiving things need energy to carry out thefunctions that keep them alive. Respiration is the process by which food is turned into energy.

M = MOVEMENT

Living things are able to move about. Animals move from place to place. Plants move by responding to light.



R = REPRODUCTIONLiving things produce offspring. Reproduction continues the survival of each species.

G = GROWTHLiving things grow, increasing in size and complexity.

N = NUTRITIONLiving things need to take in food so that respiration can occur. Nutrients in food help to build, maintain and repair the organism.

E = EXCRETIONLiving things have to get rid of unwanted waste products.


All living things carry out the seven essential life processes.

But what are living things made of?


M

S

R

N

E

R

G

= Movement

= Sensitivity

= Respiration

= Nutrition

= Excretion

= Reproduction

= Growth


7A Cells

Building blocks of life


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.


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!

How do we know about cells if they are so small?

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.


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.


Cell-ebrate the microscope!

7A Building blocks of life - Cell-ebrate the Microscope


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.

Do animal and plant cells look the same?

This is a typical animal cell.


7A Building blocks of life - Typical animal cell


7A Building blocks of life - 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?

7A Building blocks of life - Typical cells

Compare a typical animal cell and a typical plant cell.


7A Cells

Building living things


7A Building living things - Cells working together

What could you do if you were one cell?

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?

Not much! You’d be a blob, with lots of pieces floating around inside of you!


7A Building living things - Cells, tissues and organs

Identify the organs labelled in the diagram.

brain

skin

eye eartongue

heartlung

stomach

muscle

intestines


7A Building living things - Cells, tissues and organs

Cells are the building blocks of all living organisms.

Different cells do different jobs.

How do the millions of cells in your body work together?

muscle cell

Similar cells that do the same job work together to make tissue.

Muscle cells make muscle tissue.

What type of cells are nerve tissue and blood tissue made from?

muscle tissue

Different tissues work together to make an organ.

Muscle tissue, nerve tissue and blood tissue make up the stomach.

Organs work together to make an organ system.

What organ system is the stomach part of?

stomach


7A Building living things - Different cells for different jobs

Name a cell that would be suitable for each job.


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.


7A Building living things - How are new cells made?