Unit 5.2 Chromosomes

Unit 5 
Heredity and evolution

Basic 2
Chromosomes
1 / 23
volgende
Slide 1: Tekstslide
BiologieMiddelbare schoolvwoLeerjaar 3

In deze les zitten 23 slides, met interactieve quizzen en tekstslides.

time-iconLesduur is: 45 min

Onderdelen in deze les

Unit 5 
Heredity and evolution

Basic 2
Chromosomes

Slide 1 - Tekstslide

Today
Recap 5.1
Explanation 5.2
  • You can explain how each of the parents provides 50% of the chromosomes.
  • You can say how the sex of a human is determined by sex chromosomes.
  • You can explain how sexual reproduction causes variation in genotypes.

Slide 2 - Tekstslide

Which one is correct?
A
Phenotype = genotype + environment
B
Environment = genotype + phenotype
C
Genotype = phenotype + environment

Slide 3 - Quizvraag

If you look at this persons hair..
A
Phenotype
B
Genotype
C
Phenotype en Genotype

Slide 4 - Quizvraag

Put in the correct order,
from small to big.
A
cell - chromosome - DNA - gene
B
gene - chromosome - DNA - cell
C
gene - chromosome -cell - DNA
D
gene - DNA - chromosome - cell

Slide 5 - Quizvraag

Body cells
The nucleus of the body cells of a human contain 46 chromosomes. 

Every chromosome carries the information for different hereditary traits. 

Chromosomes occur in pairs. 

Two chromosomes in a pair match; they carry information for the same traits. 

There are 23 pairs.
Pair 23 are the sex chromosomes. 



Slide 6 - Tekstslide

Pair 23 are the sex chromosomes. 

Slide 7 - Tekstslide

Chromosomes
Contain DNA

Bundled DNA-fibre wrapped around proteins to make it smaller and fit into the nucleus

23 chromosome pairs in human body cells

Slide 8 - Tekstslide

Sex cells
Sex cells are different than regular body cells = egg and sperm cells. 
 
Sex cells contain 23 chromosomes. There are no pairs. 

The child has 50% of its genetic information form the father and 50% of the mother. 

Pair 23 will determine the sex of the child. This depends of chromosome 23 of the spermcell  is a X or a Y chromosome. 

Slide 9 - Tekstslide

How many chromosomes?
Male or female?

Slide 10 - Tekstslide

45, X

Slide 11 - Tekstslide

How many chromosomes?
Male or female?

Slide 12 - Tekstslide

47, XY, +21 

Slide 13 - Tekstslide

fig. 3 Different information on a chromosome pair

Slide 14 - Tekstslide

Variation in genes
  • Sex cells = no pairs of chromosomes. 
  • only 1 copy of the chromosome ends up in the egg or sperm cell.
  • result: variation in genotypes 

Slide 15 - Tekstslide

Variation in genotype
  • Due to sexual reproduction.
  • father 1/2 and mother 1/2 contribute 1 copy of chromosome.
  • Chance/coincidence!

Slide 16 - Tekstslide

Each human being has 46 chromosomes. How many did you get from your mother?
A
46
B
23
C
22
D
45

Slide 17 - Quizvraag

A person containing an XY is a...
A
man
B
woman

Slide 18 - Quizvraag

A person containing the same copy of a sex chromosome is a...
A
man
B
woman

Slide 19 - Quizvraag

You have 23 sex chromosomes in your body.
A
True
B
False

Slide 20 - Quizvraag

Slide 21 - Tekstslide

Write down the sex chromosomes of someone who is intersex.

Slide 22 - Open vraag

Let's practice 
Read basics 5.2 Chromosomes
Make the assignments 1 to 9, yes 6 as well
Extra challenge: assignment 10+11
timer
10:00

Slide 23 - Tekstslide