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1B5 Genetics
inheritable and non-inheritable characteristics,chromosomes
and genes
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1B5 Genetics
OB35understand that humans have inheritable and non-inheritable characteristics, and that inheritable characteristics are controlled by genesOB36recall that genes are located on chromosomes and that in a human there are 23 pairs of chromosomes, which are located in the nucleusOB37recall that chromosomes are made of DNAand protein
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OB35understand that humans have inheritable and non-inheritable characteristics
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)…
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OB35understand that humans have inheritable and non-inheritable characteristics
Inheritable characteristics are received from parents…
father mother
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OB35understand that humans have inheritable and non-inheritable characteristics
Check out some of your own inheritable characteristics…
Arm fold preference “Hitchhiker’s thumb” Pinkie finger alignment Ear lobe attachment
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OB35understand that humans have inheritable and non-inheritable characteristics
Check out your own…Arm fold preference: fold your
arms - ?Do you fold right-over-left or left-over-right?
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OB35understand that humans have inheritable and non-inheritable characteristics
Check out your own“Hitchhiker’s thumb”: extend your thumb –
? Is it straight or curved?
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OB35understand that 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?
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OB35understand that humans have inheritable and non-inheritable characteristics
Check out own … Ear lobes: look at your ear in a mirror –
? Is it directly attached or separated ?
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OB35understand that humans have inheritable and non-inheritable characteristics
Other inheritable characteristics include:
If you are connected to the internet, some of the images will link you to a source of information
eye colour freckles
blood type
haemophilia
cystic fibrosis
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OB35understand that humans have inheritable and non-inheritable characteristics
Some non-inheritable characteristics: Athletic ability Artistic ability Accent
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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
OB35understand that inheritable characteristics are controlled by genes
one gene for eye colour
one gene for eye colour
two genes for
eye colour
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OB36recall that genes are located on chromosomes which are located in the nucleus
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OB36recall that genes are located on chromosomes which are located in the nucleus
image from http://regentsprep.org/Regents/biology/units/heredity/dna.cfm
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OB36recall that in a human there are 23 pairs of chromosomes, which are located in the nucleus
©news.bbc.co.uk
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OB37recall that chromosomes are made of DNA and protein
• 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?
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© 2005 Chugoku Rosai Hospital
OB37recall that chromosomes are made of DNA and protein
• 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
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OB37recall that 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
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OB37recall that chromosomes are made of DNA and protein
• the code in DNA is different in every human being…except for ?????
IDENTICAL TWINScan you explain why
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How small is DNA?If you are connected to the internet, click on the image below to get an idea
OB37recall that chromosomes are made of DNA and protein
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Genetics
OB35understand that humans have inheritable and non-inheritable characteristics, and that inheritable characteristics are controlled by genesOB36recall that genes are located on chromosomes and that in a human there are 23 pairs of chromosomes, which are located in the nucleusOB37recall that chromosomes are made of DNAand protein