5.2

• Biologie
• Middelbare school
• vwo
• Leerjaar 2

5.2 DNA and genes

DNA

karyogram from a woman

22 pairs and
1 pair sex chromosomes 

chromosomes contains

inheridant information on the DNA

In every body cell you have the same information 
a male has 46 chromosomes--> 22 pair and XY

a female has 46 chromosomes--> 22 pair and XX

New cells are made by mitoses (same DNA)

In every body cell you have the same information

Half of the chromosomes are from dad and half from mom

They make one chromosomepair

with different information on every chromosome

A gene:
A fraction of the chromosome contains information for 1 inheredental information ( hair colour, eye colour)

The information for this feature can be different from mom and dad) 

Egg cells / Sperm cells

contain half of the chromosomes from a body cell

Are made by meioses

only in the reproduction organs

DNA is different 

nucleotides (base of DNA)

4 different bases (nucleotides)

cytosine

guanine

adenine

thymine

double helix (ladder)

information is stored in code

AATCCGGACGAATTCCGGAAAAAATTTTTTTTTTTTTTTTTTCGCGCGAATTCATATATATCGGACGGACGAAC etc etc etc it would be a very thick book :-)

GENE: section of DNA with complete code for a protein

proteins

determine almost everything...

one gene = code for one protein

one or several proteins = one characteristic (hereditary trait)

copying

you start with one fertilised egg with 46 chromosomes...

you end up with billions of cells with the same 46 chromosomes => all of them a copy from the original.....

things can go wrong on the way => mutations (5.5)

from DNA code to proteins

The molecule
shown in the
picture is called ...

1. DNA
2. single stranded DNA
3. an amino acid
4. a ribosome

This is a picture of ..

1. chromosome
2. gene
3. DNA
4. cell

Below are a few codes with 4 letters.
Which of these codes show a piece ofDNA?

1. ABCDBDCA
2. CAEFEAFC
3. GACTATGC
4. TACDDTAC

What do you call the part of a chromosome that carries the information for 1 heriditary trait?

1. DNA
2. a gene
3. a mother cell
4. an egg cell

Does the information for hereditary traits change when a cell is copied?

1. yes
2. no

this is a picture of ........

1. cell
2. chromosome
3. DNA
4. gene