Similarity and kinship

• Biologie
• Middelbare school
• havo
• Leerjaar 1

Welcome!

Today:

Explanation about species and similarity (page 176)

Making exercises 

What are we going to learn today?

Today we'll be learning:

When 2 organisms belong to the same species. 

The difference between species and races.

How similarities within organisms help us classify them. 

Levels of organization 

Are a oak tree and Christmas tree the same species?

Are a monkey and kangaroo the same species?

Are a donkey and a horse the same species?

Are a poodle and a labrador the same species?

Species

You speak of the same species when 2 organisms can have FERTILE offspring, which means they have offspring that can have offspring themselves.

A species can have several races. 

 

Evolution

Within a group of the same species are many differences (variation):

Hair colour, eye colour, height and behavior.

Some of these characteristics are better adapted to the environment, thus selected by it.

When this continues on, some characteristics will originate and some of them will disappear. This is called evolution. 

Ancestry

Through characteristics and DNA we can see how much organisms look like each other, they are often related to each other. You can process this information in a ''family tree''. The dots represent the last common ancestor of the two animals.

The animals with the least amount of crossroads between them are very related to each other. 

Ancestry

Another method we use for this is DNA-sequencing. Here we take a look at the DNA sequence (A-T, C-G) of different animals. When they look like each other they are very related. When they have little in common, not some much. 

Time to work!

The homework for the next lesson are the exercises of paragraph 3.2. You can start working on them now.