I want my class to know… I’m learning (just like you!) I make mistakes (just like you!) I’m here to help you I genuinely care about your personal growth and academic success
Getting to know Ms. Muirhead: Two Truths and a Lie
a) My favourite colour is purple b) I own a motorcycle c) I like to knit
a) My favourite colour is purple b) I own a motorcycle c) I like to knit
a) Skiing is one of my favourite hobbies b) I am an only child c) I am not from the lower mainland
a) Skiing is one of my favourite hobbies b) I am an only child c) I am not from the lower mainland
a) Both my parents are teachers b) I share my name with a Disney princess c) I am 28 years old
a) Both my parents are teachers b) I share my name with a Disney princess c) I am 28 years old
DNA The illustration is a ‘model’ of the double helix forming part of a DNA molecule (Slide 14)
What is DNA? Where is DNA found?
DNA stands for deoxyribonucleic acid This large molecule is present in the nucleus of all cells in all living organisms DNA controls: All the chemical changes which take place in cells The kind of cell which is formed The kind of organisms which is produced
DNA is a very large molecule made up of a long chain of sub-units The sub-units are called nucleotides Each nucleotide is made up of: A deoxyribose sugar A phosphate group A nitrogenous base
There are 4 types of bases: Adenine (A) Guanine (G) Cytosine (C) Thymine (T)
combine to form a nucleotide The deoxyribose, the phosphate, and one of the bases combine to form a nucleotide phosphate base deoxyribose sugar PO4 It is the phosphate group which gives DNA its acidic properties
(Literally. There are 6 billion bases in the human genome.) A molecule of DNA is formed by millions of nucleotides joined together in a long chain. (Literally. There are 6 billion bases in the human genome.) PO4 sugar-phosphate backbone + bases
DNA consists of a double strand of nucleotides The sugar-phosphate backbones are on the outside and the strands are held together by hydrogen bonds between the bases The two strands together twist to form a double helix
PO4 PO4 PO4 PO4 PO4 PO4 PO4 PO4 PO4
The bases always pair up in the same way Adenine forms a bond with Thymine Adenine Thymine and Cytosine bonds with Guanine Cytosine Guanine This is called complementary based pairing
PO4 adenine cytosine PO4 thymine PO4 guanine PO4 PO4
14 THE DOUBLE HELIX bases sugar-phosphate chain
Video: DNA Structure https://www.youtube.com/watch?v=qy8dk5iS1f0
Check-In Which is not a component of DNA? A nitrogenous base An organic acid A phosphate A sugar molecule
What is a sub-unit of DNA called? Adenine Double helix Deoxyribose Nucleotide
What are the correct pairings for nucleotides? Adenine-Guanine/Cytosine-Thymine Thymine-Guanine/Adenine-Cytosine Cytosine-Guanine/Adenine-Thymine Thymine-Thymine/Guanine-Guanine/Adenine-Adenine/Cytosine-Cytosine
Which of these statements is true? Complementary base pairs are held together with hydrogen bonds The sugar phosphate backbone is in the middle of a molecule of DNA Three DNA strands make up a helix
DNA contains thousands of genes Gene: a sequence of DNA that provides instructions to make a protein Humans have ~23,000 genes These proteins contribute to our chemical and physical traits (trait: characteristic)
DNA and Heredity We get half of our DNA from our mother and half of our DNA from our father (How do we get this DNA?) This new combination of genetic material makes us the unique individual we are!
DNA’s Role in Evolution DNA is the only thing that is passed from one generation to another Traits that are passed from one generation to another are called heritable traits The process of evolution is able to act on these heritable traits
Video: DNA and Heredity https://www.youtube.com/watch?v=uXdzuz5Q-hs
We’re all a little bit closer than you think https://www.youtube.com/watch?v=OCioHPN_QqI