5.1 pass it on!

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

Chapter 5

 

It runs in 

the family

5.1 pass it on!

How much do you think that humans share their DNA with a banana? (give a percentage)

What about a chimpansee?

Can you roll your tongue?

1. Yes
2. No
3. Kinda

Do you have a Widow's peak or a straight hairline?

1. Widow's Peak
2. Straight hairline
3. I have no idea honestly

Can you turn your tongue?

1. yes
2. no
3. Little bit

Attached earlobe or free earlobe

1. Attached
2. Free
3. idk

new chapter: it runs in the family

- inheriting characteristics from parents

- how gender is determined

- how chomosomes, DNA and genes are related

- how to determine characteristics of offspring from a given combination of parents

- how to read a pedigree

Genetic material

• Genetic material is located in the nucleus of every cell.
  
• Each nucleus has chromosomes  that contain DNA.
  
• The genetic material is located in DNA molecules.
  
• Nuclei of human cells have 46 chromosomes.
  

Chromosomes

The long thin threads of DNA are bundled together into  chromosomes (Fig. 1)

Chromosomes are located in the nucleus of every cell in your body (except red blood cells).

The chromosomes contain all information for all you hereditary traits. (Fig. 2)

Fig. 1

Fig. 2

Chromosomes

Body cells

The first 22 pairs of chromosomes are present in every human (called autosomes). 

The 23rd pair is special because they are not always the same. These are the sex chromosomes.

Sex chromosomes determine whether your genetic sex is male or female. 

Males have X-Y chromosomes

Females X-X chromosomes. 

sex chromosomes

Female:

Male:

genotype

complete set of inherited characteristics (genes/alleles, will get to that later ;-))

fenotype

Characteristics that are actually expressed (which show, which could also be 'inside' like a disease or a fast metabolism)

genotype

fenotype

Wat is genotype or fenotype? move traits A till H to genotype or fenotype. 

Genotype

Fenotype

a small nose

straight hair from birth

Piercings 

painted dark hair

a scar

Sarah can play the piano very well

calluses on your hands

blue eyes

karyotype

- picture of all your 46 chromosomes

- 23 homologous pairs (1 from dad and 1 from mum)

- 22 pairs of autosomal chromosomes

- 1 pair of sex chromosomes XX or XY

fenotype = genotype + environmental factors

It runs in the family

so why do siblings differ?

homework

study 5.1 do exercises 1, 2, 3, 4 and 5

15 minutes