U5 B4 2HVTTO

• Biologie
• Middelbare school
• havo, vwo
• Leerjaar 2

B4 The theory of evolution

• Take off your jacket
• Put your things on your desk

       Book, notebook, pencil case

• Bag on the floor
  
• Read pages 127-134

Lessongoals

• Understand: I can explain what evolution is as a process of species changing over time.
• Understand: I can explain the three main mechanisms of evolution — variation, natural selection and speciation — by using appropriate examples.
• Apply: I can use evidence such as fossils or observations to support the theory of evolution.

Homework 5.4

Asgmt 1-7, (4)

OR challenge

Asgmt 5-9

Secret Student

This lesson, I have randomly picked someone to be the secret student.

I pay special attention to:

• Your use of English
• Your participation in the lesson

At the end I will reveal the secret student, If I can give them positive feedback, they also earn 1/3 +0,5 OR +1 cm² cheat sheet.

Wheel of homework

Go to Lessonup.app and use this code

Reward

Penalty

Rewards

• +1 cm2 cheatsheet = you get to make a cheatsheet for a test. This starts being 1 by 1 cm. Everytime you earn this it gets 1 cm bigger to a max of 4 by 4 cm.
• 1/3 +0.5 = If you earn this 3 times you get to add 0,5 to one of your biology marks.
• Snitch = You can pick a classmate who also is checked for homework, you earn two V's (having 3 earns you a 1/3 +0,5)
• Too bad = You only get one V
  

penalties

• 45 min extra worktime = you need to come after school and do homework, this will last for 45 min or until the task is done
• Coloringpage = You get to pick a coloringpage, You need to color it and perform tasks that might be on it. You need to hand it in during the next lesson, If you don't you get 2 marks.
• 2/1 marks = a mark is an X, if you get 3 of these you will automaticly earn the 45 min extra worktime.
• Snitch = You can pick a classmate who also is checked for homework
• Lucky! = You don't get a penalty

Senna dyes her hair blond.
Weeks later, she has her original hair colour again.

What has happened?

1. The genotype changed, later the phenotype changed the genotype back to how it was
2. The phenotype changed, later the phenotype changed the genotype back to how it was
3. The phenotype changed, later the genotype changed the phenotype back to how it was
4. The phenotype changed, later the phenotype changed the phenotype back to how it was

Which cells in the body contain genes for body size?

Pick the most correct answer

1. Cells in the legs
2. Cells in the legs and bones
3. Cells in the legs, bones and brain
4. Cells in the legs, bones, brain and eyes

The picture shows an eye
cell with chromosomes of an unknown organism.

Which of the answers shows what a cell of this organisms intestines could look like?

1. 
2. 
3. 
4. 

The picture shows an eye
cell with its chromosomes of an unknown organism.

Which of the answers shows what this organisms sperm cells could look like?

1. 
2. 
3. 
4. 

Each gene has many variants (blond, brown, ginger, etc).
If you were able to look in someone's DNA and see the variants of 1 gene pair.
What would be the highest amount of variants you could find?

1. 1
2. 2
3. 3
4. 4

What isn't a mutagenic influence?

1. Sunlight
2. Röntgen radiation
3. Smoke
4. Dirty water

Both parents are homozygous for blond hair.
How big is the chance for their kid to be homozygous for
blond hair too?

1. 0%
2. 25%
3. 75%
4. 100%

Mother is homozygous and has blond hair
Father is heterozygous and has blond hair

Is it possible for their kid to have a different hair colour than blond?

1. Yes
2. No

The theory of evolution

Comparable to a fairy tale

I don't really know what it says, so I don't have an opinion

I'm not entirely sure about it. But don't think it's made up

I'm very sure it's absolute truth

other

Evolution has to do with ..

Theory of evolution is about...

• The emergence of new species (all organisms)
  
• The way in which these species arise
  
• Determining which species are related to each other

emergence = the fact of starting to exist or becoming known for the first time

Evolution is NOT about ..

• How life came to be
• How the universe/solar system/earth/etc. came to be
• If God exists

3 main mechanisms

Evolution can be summarized  into these 3 mechanisms:

1. Variation in genotypes
2. Natural selection
3. New species arise

Variation in genotypes

• Sexual reproduction and mutations> new/different genotypes
• New genotypes > new/different phenotypes
• Lots of changes in genotype >    DNA changes 'too' much > new species

Sexual reproduction = reproduction in which two sex cells from two different organisms join together to form a new organism.

Because of meiosis, many different sex cells are made inside one organism. These cells are then combined by chance with the sex cells of another organism.

This creates new organisms with different DNA (new genotypes).

When the genotype is different, the phenotype (how an organism looks or functions) can also be different.

That’s why even organisms from the same species are all a little bit different.

If the genotype or DNA changes too much, it can become so different that the organism becomes a new species.

Note: This usually takes a very long time – thousands of years.

For example, the Darwin finches were once all the same species.

Because of changes in their genotypes, the shape of their beaks (their phenotype) slowly changed.

Nowadays, there are many different kinds of finches, but they were once all the same species.

Natural selection

• Species who have adapted to 

        their environment will survive

        and reproduce

• 'Good' genes are passed  on
• 'Bad' genes dissapear

Being “adapted” depends a lot on the environment!

• A thick fur is useful in a cold environment, but not in a hot one.
• Pointy teeth are only useful if you eat meat.
• A big and strong body only helps if you can also find enough food.

!

What is the deciding 'thing' that tells you that two organisms belong to the same species?

New species arise

Animals of same species are  split up

The environment slowly changes.

Because of natural selection, other genes are 'good' in new environment

Species have become different species after many years of evolution, due to living apart

more examples

New species arise

• New species arise due to LONG periods of evolution in a species
• Many small changes together  become big changes

• Evolution takes very long! (thousands of years)

This image makes me think ..

Theory of evolution

Still comparable to a fairy tale

I understand it better, still don't really believe it

I don't understand it entirely, but seems logical

This is the way we got all the organisms we have today

What you should do: 5.4

• Pages  127-134
• Asgmt  1-7, (4)

OR challenge

• Asgmt 5-9

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zs = Working in Silence

• No asking questions
• Silent, don't disturb anyone
  
• Stay at your  desk

What you should do: 5.4

• Pages 127-134
• Asgmt 1-7, (4)

OR challenge

• Asgmt 5-9

Done with the above?

• Work on the next chapter(s)
• Learn for the test 
• Make other homework
• Read a book

Zw = Working with whispering

• Teacher is available for questions
• Only whisper with the student next to you
• Stay at your  desk

Some people find evolution hard to 'believe' in,
because they don’t really 'see' it happening.

Why is evolution so hard to 'see' for most people?