Download Inheriting Characteristics

Inheriting Characteristics
L.O: To understand how we inherit
characteristics from our parents
Peter Griffin
Lois Griffin
Meg Griffin
Chris Griffin
Stevie Griffin
What
features do
Lois and
Meg share?
How are
they
different?
What features do Peter and Chris
share? How are they different?
1. Label pictures to describe the contents
of the nucleus in terms of
chromosomes, genes and DNA
2. Explain what genes do
3. Explain why parents have similar
characteristics to their offspring in
terms of gametes and genes
Extracting DNA from kiwi
1. Add 10ml of washing up liquid to a jar, to that add
100ml of water 3g of salt
2. Add finely chopped kiwi to the jar
3. Shake the jar for 30secs then leave for 15mins
4. Do the worksheets while you are waiting
5. Filter the mixture after 15mins
6. Put 5ml of the liquid into a boiling tube add 5ml of cold
ethanol down the side of the tube
7. After a minute white strands will appear in a layer this is
the DNA
• In as much detail as you can describe
how we inherit features from our
parents
Keywords you must try to include:
Sperm, egg, gametes, genes, nucleus,
chromosomes, DNA,
Fertilization animation
FLASH 6 – Fertilisation
FLASH 2 – Mitosis drag & drop
Write a definition for each of the
keywords whilst we go through the
slides:
•
•
•
•
•
Gametes
Nucleus
Chromosomes
genes
DNA
What is in a cell?
The gametes
• Are the sperm and egg cells
• They contain half the genetic
information of a normal body cell
• When joined together the
fertilised egg will have a complete
set of genetic information
The Nucleus
• All body cells have a nucleus.
• The nucleus contains all genetic information
• Is said to be the “brain” of the cell as the
genetic information controls what the cell
does
• The nucleus contains 23 pairs of
chromosomes
The chromosomes
• A human cell contains 23 pairs of chromosomes,
you have 2 of each chromosome (unless you’re a
boy)
• This means there are 46 chromosomes in total
• You inherit half your chromosomes from your
mother and half from your father. Making 23 pairs.
• Chromosomes carry genes
The genes
• Genes or groups of genes code for your
characteristics
• Genes are made up of short lengths of DNA
• DNA stands for Deoxyribose Nucleic Acid
• In the 1950’s Watson and Crick were the first to
come up with the structure of DNA
• On each chromosome of the pair there can be
different version of the same gene, i.e. blue or
brown eyes
• The variations are known as “alleles”
What is DNA?
Chromosomes and their genes are made of a molecule
called DNA.
DNA stands for
deoxyribonucleic
acid.
Each chromosome
is a very long molecule
of tightly coiled DNA.
DNA molecules carry the code that controls what your cells
are made of and what they do.
Which part of a DNA molecule holds this information?
Structure of DNA
Variation – what causes it?
Two things – Genetics &
Environment
Genetic variation
• You get ½ your genes from your
mum & ½ from your Dad
• So you have some characteristics in
common with both parents but you
look different too - VARIATION
What’s the order?
© Boardworks Ltd 2004