Genetics. New Learning Goal: To describe how genetics are passed from one generation to another

Genetics

New Learning Goal:

To describe how genetics are passed from one generation to another.

Fun Facts….

1. Monkeys and Humans have 98.8%of the same DNA.

2. Humans have 50% of the same DNA as bananas.

3. You get 99.9% of your DNA from your parents.

Let’s let my buddy, Bill Nye introduce us to Genetics…. http://www.youtube.com/watch?v=OZIQTMHmWm

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Gregor Gregor MendelMendel(1822-1884)(1822-1884)The Father The Father of Geneticsof Genetics

Gregor Johann MendelGregor Johann Mendel

Austrian monkAustrian monkStudied the Studied the inheritanceinheritance of of traits in traits in pea plantspea plantsDeveloped the Developed the laws of inheritancelaws of inheritanceMendel's work was Mendel's work was not recognized not recognized until the turn of until the turn of thethe 20th century 20th century

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Gregor Johann MendelGregor Johann Mendel

Between 1856 Between 1856 and 1863, Mendel and 1863, Mendel cultivated and cultivated and tested thousands tested thousands of pea plantsof pea plants

He found that He found that the plants' the plants' offspring retained offspring retained traits of the traits of the parentsparents

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Mendel stated that Mendel stated that physical traits are physical traits are inherited as inherited as “particles”“particles”Mendel did not Mendel did not know that the know that the “particles” were “particles” were actually actually Chromosomes & Chromosomes & DNADNA

Particulate InheritanceParticulate Inheritance

I. What is genetics?

i. Genetics

The study of _______ (how traits are passed from parents to offspring)

I. What is genetics?

i. Genetics

The study of heredity (how traits are passed from parents to offspring)

ii. Heredity

How an organism passes ____ from one generation to the next.

ii. Heredity

How an organism passes traits from one generation to the next.

iii. Trait

A __________ or quality of an organism

iii. Trait

A characteristic or quality of an organism

v. Variability

The differences between ________ in a given population

v. Variability

The differences between organisms in a given population

vi. Adaptation

A structure or behavior that allows an organism to survive in its environment.

sidewinder article

Exit Ticket

1. Who is the father of Genetics?

2. What is heredity?

3. What is a trait?

4. Describe adaptation that we saw with the snakes.

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New Learning Goal:

To describe how genetics are passed from one generation to another.

BrainPop Time….

http://www.brainpop.com/health/geneticsgrowthanddevelopment/dna/

DNA stands for deoxyribonucleic acid

This chemical substance is present in the nucleusof all cells in all living organisms

The kind of cell which is formed, (muscle, blood,nerve etc.) is controlled by DNA

The kind of organism which is produced (giraffe, herring, human, etc.) is controlled by DNA

DNA 2

Ribose is a sugar, like glucose, but with only fiveOxygen atoms in its molecule

Deoxyribose is almost the same but lacks one oxygen atom

Both molecules may be represented by the symbol

Ribose & deoxyribose

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The most common organic bases are

Adenine (A)

Thymine (T)

Cytosine (C)

Guanine(G)

The bases 5

The deoxyribose, the phosphate,

and one of the bases

adenine

deoxyribose

PO4

Combine to form a nucleotide

Nucleotides 6

A molecule of DNA is formed by millions of nucleotides joined together in a long chain

PO4

PO4

PO4

PO4

Joined nucleotides 7

In fact, the DNA usually consists of a double strand of nucleotides

The sugar-phosphate chains are on the outsideand the strands are held together by chemical bonds between the bases

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PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

2-stranded DNA 9

The bases always pair up in the same way

Adenine forms a bond with Thymine

and Cytosine bonds with Guanine

Bonding 10

Adenine Thymine

Cytosine Guanine

PO4

PO4

PO4

thymine

PO4

PO4

PO4

PO4

adenine

cytosine

PO4

guanine

Bonding continued 11

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

PO4

Pairing up 12

The paired strands are coiled into a spiral called

A DOUBLE HELIX

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sugar-phosphatechain

bases

THE DOUBLE HELIX

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A model ofpart of a DNA molecule

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Build a DNA molecule – you try it!

Your Exit Tickets will be Passed Out Now

CHROMOSOMES

New Learning Goal:

To describe how genetics are passed from one generation to another.

Numbers of chromosomesConstant for each cell in the

body.Constant throughout the life

of an individual (you don’t lose or gain chromosomes)

Constant for all members of a species

© 2007 Paul Billiet ODWS

Organism Chromosome numbers

Human 46

Chimpanzee 48

House Mouse 40

Maize 20

© 2007 Paul Billiet ODWS

Human chromosomes

Identifying chromosomes

Chromosomes can be identified by:

Their size Their shape and flexiblity Banding patterns

Chromosomes are analyzed by organising them into a KARYOTYPE

© 2007 Paul Billiet ODWS

Female Male

YXX X

Possible children

FatherMother

XX XY

Chance of a girl 50% Chance of a boy 50%

X Y

X XX XY

X XX XY

The inheritance of gender

Exit Ticket:

On the back of your notes, create a Punnett Square for Blue Eyes and Brown Eyes.

Dominant and Recessive Traits

New Learning Goal:

To describe how genetics are passed from one generation to another.

Before we begin, let’s take a look at a quick video….

http://www.youtube.com/watch?v=Mehz7tCxjSE

What are traits?

Physical Traits Can be seen by others Eye color, hair color, height, left handed

Acquired Traits Learned skills Playing a sport, riding a bike, playing a

musical instrument Behavioral Traits

Instinctual actions Nest building and migration

Terms Used in Modern Genetics

Genotype The particular alleles (genes) an individual

carries They are inherited from your biological parents Genes control your traits

Phenotype An individual’s observable traits

What people can SEE when they look at you

Terms Used in Modern Genetics

An individual with non-identical alleles of a gene is heterozygous for that gene Examples: Bb, Tt, Aa

An individual with identical alleles of a gene is homozygous for that gene Examples: BB or bb, TT or tt

Two or more alternative forms of a gene.

Terms Used in Modern Genetics

An allele is dominant if its effect masks the effect of a recessive allele paired with it Capital letters (A) signify dominant

alleles; lowercase letters (a) signify recessive alleles

Homozygous dominant (AA) Homozygous recessive (aa) Heterozygous (Aa)

What traits do you have?

We will go through the most common traits that people have

On your sheet, record if you have the mentioned trait or not

You may have to ask your neighbor for help

Detached (EE, Ee) or attached (ee) Earlobes

Can Tongue Roll (TT, Tt) or Can’t (tt)

Dimples (DD, Dd) No Dimples (dd)

Right (RR, Rr) or Left (rr) handed?

Freckles (FF, Ff) No Freckles (ff)

Curly (HH, Hh) or Straight (hh)

Cleft Chin (CC, Cc) or No Cleft (cc)

Allergies (AA, Aa) or No Allergies (aa)

Normal (BB, Bb) Color Blindness (bb)

Can you see the number inside the circle?

If you cannot, you may be colorblind

Widow’s Peak (WW, Ww) or Straight (ww)

DataPlease compare your results

(the chart) with 5 other students.

Does our data support which genes are dominant and which genes are recessive?