External Features of Animals

• There are many different kinds of animals in the world. 

• Some of them look similar but some are different.

• Animals can be identified by their external features. 

•  Parts of the body of an animal that we can observe are called external features of that animal.

 EXAMPLE:
 

All pictures are from Google Image. 

Grouping of Animals

External features can be used to group animals.

Can be grouped according to their similarities. 

http://looking-for-animated-gifs.piczo.com/animals?cr=7&linkvar=000044

 

1. Animals with four legs : elephant, cow, dog, cat 
2. Animals with two legs : chicken, duck, horn bill bird 

 
- Fish, crocodile, snake can be put in the same group because their bodies are covered with scales.  

- Crocodile can also be put in the same group as rat, tiger and kangaroo because they have FOUR LEGS. 

  

  

 ~Take a Break~

 

    http://www.youtube.com/watch?v=PR3UCF4QGEw

Let's think

http://www.shutterstock.com
/pic-17259106/
stock-photo-two-butterfly-wings.html

A) I have wings. My wings are colourful. My body has no feathers. 
     I am a _________.



  B ) The body of a lizard is covered with ( fur / scales / hair )

  C ) What are the differences between a prawn and a fish?
                                

ATTENTION!

http://www.youtube.com/watch?v=_ZgcBUx0Vwg

Different Ways of Grouping Plants

Grouping of Plants

Plants can be grouped according to their similar external features,
Most plants have these features : leaves, stem, or flowers. 
All these features may look different or similar. 

1.  Flowering Plants

https://www.youtube.com/watch?v=pHNc-8GaURU

  

2.  Woody Stem Plants

3.  Soft Stem Plant

Do You Know?

Sugar cane plants DO NOT have fruits.

Maize and sugar cane plants are SIMILAR because both are flowering plants, have long leaves and soft stems.

External Features of Plants

The different parts of a plant that we can observe is called the external features. 
Most plants have the SAME main parts: leaves. stems, flowers and fruits. 

http://chinaflowers.net/blog/sunflower-care-instructions.html

However, these features do not look the same.   

1. FLOWERING  PLANTS
2.   NON-FLOWERING  PLANTS

 - Some plants have yellow or red leaves, 
 - Some leaves are shiny and some are dull.
 - Shape of leaves can be irregular, oval, round or long.
     

Papaya Tree

-Woody Stem    

-Flowering Plant 

-Green Leaves   

Rose  

- Woody Stem

- Flowering Plant   

- Thorns

- Oval shape leaves

Bougainvillea 

- Woody Stem

- Flowering Plant

- Green Leaves

Attract or Repel

Magnets come in different shapes and sizes. These are some of the different shapes of magnets. 

http://181607523.en.made-in-china.com/product/KbPnWISYEHVZ/China-Ring-Magnet-Y25-.html

http://www.sau83.org/staff/grade1/magnets

http://it.wikipedia.org/wiki/File:Horseshoe_magnet_by_Zureks.jpg

http://www.poshbadges.com/products_Results.php?S_prodcatid=3&Search.x=60&Search.y=18&Search=Search

http://www.kbescientific.com.sg/lab_apparatus.htm

http://www.stanbridges.com.au/shop.TH1873 

When we put two magnets close to each other, they can either attract or repel each other. Different poles of magnets attract. Same poles of magnets repel.

http://victoriahennen.edublogs.org/science-and-technology-2/magnets/

South pole repels South pole.
North pole repels North pole.
South pole attracts North pole. 




 If you break a bar magnet into two, you do not separate the North and South poles. You will get two news magnets.

Handling Magnets

WHY do some magnets become weak? 

We should not heat, knock or drop a magnet. As a result, the magnet will lose its magnetism and become weak. 
When the bar magnets are not in use, they should be kept in pairs, North pole to South pole, with an iron keeper at each end.

http://www.schoolorders.com/e1.html

Does a compass work best when close to magnet? 
NO. Being near a magnet (or magnetic field) completely puts off the compass as the compass is influenced by it and will not align with the Earth's natural magnetic field.

Magnets Attract some Materials

What are the objects attracted to magnets? 

Magnet attracts objects which are made of iron.
They are called magnetic objects. 
Objects which are not attracted to magnets are called non-magnetic objects. 

Objects attracted to magnet :                                

a ) paper clips
b ) scissors
c ) steel wool
d ) iron nails

Objects not attracted to magnet :
a ) pencil
b ) wood
c ) plastic
d ) paper
e ) glass

https://www.youtube.com/watch?v=zG7aTiDMnqc

Strengths of Magnets

Different magnets have different strengths.

How do you know which magnet is stronger?
Some magnets can pick up more objects than the others. These magnets are said to be stronger.
One way of measuring the strength of a magnet is by counting the number of paper clips that the magnet can attract and hold.

The magnet that holds the most number of paper clips is the strongest.

However, the strength of magnets do not always depend on their sizes. Some large magnets can be weak but some small magnets can be strong.

https://www.youtube.com/watch?v=BOxiOUIBtlg

How STRONG are magnets?? Take a look!

http://www.youtube.com/watch?v=0sfaacKAoYo

 

Uses of Magnets

Magnets are used in many things. Can you name the things that use magnets? 


Magnets have many uses in our daily life.
Magnets are used in many things such as in refrigerator, pencil case and compass.
Moreover, some train have no wheels. Same poles of magnets at the base of train and track makes the train float and move without touching track.