Genes and alleles

Welcome!
Today:
Questions about 5.2
Explanation about genes and alleles (paragraph 5.3, page 118)
Making homework 
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Slide 1: Tekstslide
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In deze les zitten 18 slides, met interactieve quizzen en tekstslides.

time-iconLesduur is: 45 min

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Welcome!
Today:
Questions about 5.2
Explanation about genes and alleles (paragraph 5.3, page 118)
Making homework 

Slide 1 - Tekstslide

The chromosomes of the same pair have the same genes but different variations of them.
A
True
B
False

Slide 2 - Quizvraag

A human cell has 23 chromosomes, so it must be a...
A
Body cell
B
Sex cell

Slide 3 - Quizvraag

A cell of a random organism has 7 chromosomes, this must be a...
A
Sex cell
B
Body cell

Slide 4 - Quizvraag

A cell of a random organism has 17 pairs of chromosomes. This must be a...
A
Body cell
B
Sex cell

Slide 5 - Quizvraag

What are we going to learn today?
We are going to learn:
How DNA is structured.
What genes and alleles are.
What happens when your DNA changes. 

Slide 6 - Tekstslide

Building your genotype

Slide 7 - Tekstslide

DNA
DNA consists of 2 strands, built up with phosphorus and sugar. However, between these strand you will find bases. There are 4 variants of these: A, T, C and G. Every connection between strands consists of 2 bases: A is always attached to a T, a C is always attached to a G. 

Slide 8 - Tekstslide

DNA 

Slide 9 - Tekstslide

Genes and alleles 
A piece of DNA that says something about one characteristic is called a gene, like a gene for hair color, height or heightened risk for a certain disease. 
A gene can have several variations. These are called alleles. You always get two per characteristic: one from your mom and one from your dad. 

Slide 10 - Tekstslide

Variants of genes: alleles 

Slide 11 - Tekstslide

Both alleles are as strong 

Slide 12 - Tekstslide

Mutations
DNA can change from time to time for several reason. The consequences resulting from that change range from non-existing to life changing. A mutation in a body cell is often less dangerous than a mutation in a sex cell. That's because two sex cells determine the whole genotype of a new life. 

Slide 13 - Tekstslide

Example 1: Albinism

Slide 14 - Tekstslide

Example 2: cancer
One mutation can result in cells dividing rapidly, using a lot of your body's resources. This is called a tumour. Tumours can stop growing at one point, but when they don't they are called malignant. They keep growing and growing. When this happens you have cancer. A next stage in cancer is metastasis, where the cancer spreads through your circulatory or lymphatic system to other organs. 

Slide 15 - Tekstslide

Stages of cancer 

Slide 16 - Tekstslide

Causes for mutations (mutagenic influences)

Slide 17 - Tekstslide

Get to work!
The homework for next lesson are the exercises of paragraph 5.3, starting on page 122. You also need to make the summary. You can start with them now. 

Slide 18 - Tekstslide