Inheritance. Some characteristics are passed on from parents to children these are called inheritable

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1 Genetics

2 Inheritance Some characteristics are passed on from parents to children these are called inheritable Other characteristics are independent of parentage these are called non-inheritable These characteristics may in turn be passed on to the following generation(s) These characteristics will not be passed on to the following generation(s)

3 What are chromosomes? Genetic materials found inside the nucleus of a cell Made up of DNA & protein Appear as very thin & thread-like structures Each cell in each type of organism has a definite number of chromosomes

4 gene controlling skin colour gene controlling tongue rolling chromosome gene controlling eye colour gene controlling blood group A gene is a short length of DNA on a chromosome which is a unit determining an inherited character It consists of a chemical substance called deoxyribonucleic acid (DNA)

5 gene controlling skin colour gene controlling tongue rolling chromosome DNA is responsible for telling the cell to make the right type of protein & control the metabolic activities of the cells gene controlling eye colour gene controlling blood group

6 Human Traits

7 Genetic Cross

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12 Inheritance Inheritable characteristics are received from parents father mother

13 Inheritance Check out some of your own inheritable characteristics Arm fold preference Hitchhiker s thumb Pinkie finger alignment Ear lobe attachment

14 Inheritance Check out your own Arm fold preference: fold your arms -?Do you fold right-over-left or left-over-right?

15 Inheritance Check out your own Hitchhiker s thumb : extend your thumb? Is it straight or curved?

16 Humans have inheritable and non-inheritable characteristics Check out your own Pinkie fingers: place them side by side? Are they straight or curved away from each other?

17 Inheritance Check out own Ear lobes: look at your ear in a mirror? Is it directly attached or separated?

18 Inheritance Other inheritable characteristics include: eye colour freckles blood type haemophilia cystic fibrosis

19 Humans have inheritable and non-inheritable characteristics Some non-inheritable characteristics: Athletic ability Artistic ability Accent

20 Inheritable characteristics are controlled by genes For each inheritable characteristic, a human has two genes one passed on by the father s sperm cell, the other by the mother s egg cell one gene for eye colour one gene for eye colour two genes for eye colour

21 Genes are located on chromosomes which are located in the nucleus

22 Genes are located on chromosomes which are located in the nucleus image from

23 In a human there are 23 pairs of chromosomes, which are located in the nucleus news.bbc.co.uk

24 DNA DNA stands for deoxyribonucleic acid it is a molecule built in a particular code the code contains instructions for every structure and function the body will ever need the DNA code for each separate structure or function is called a gene this makes it a very very long molecule so how does it fit into a very tiny nucleus?

25 Chromosomes are made of DNA and protein 2005 Chugoku Rosai Hospital the long DNA molecule is so twisted and coiled so that it takes up tiny little space each twisted coil of DNA, containing many genes, makes one chromosome small molecules of protein help keep the chromosome in shape

26 Chromosomes are made of DNA and protein the code in DNA is different in every human being (except for?????) Each individual s unique code is called their DNA fingerprint because of this, DNA is used in crime scene investigation parental disputes

27 DNA the code in DNA is different in every human being except for????? IDENTICAL TWINS can you explain why

28 How small is DNA? If you are connected to the internet, click on the image below to get an idea