DNA

DNAWhat is cancer? Do you know anyone who has been affected by cancer?

Write 3-4 complete sentences explaining your ideas

Think – Pair – Share

Think – Independently write down your ideas. This part of the process should be quiet

Pair – Talk with the person next to you about your ideas. Both partners should have a chance to speak

Share – Come together in small groups or as a whole class. Students should share their paired discussions in the large group

Intro To The Cell Cycle

Wait… What was a cell again?

A cell is the basic unit of all living things Prokaryotic

(mostly bacteria)▪ No membrane-bound organelles

Eukaryotic (plants, animals, etc.)▪ Membrane-bound organelles

There was also that “cell theory” thing…

1. All living things are made of one or more cells

2. Cells are the basic unit of life

3. Cells can only arise from pre-existing cells

Cells can only arise from pre-existing cells…

…through cell division!

Some cells are dividing all the time…Thousands of new hair and skin cells per day

Others rarely, if ever, divide…You have all the brain cells you will ever haveEvery time you drink or do drugs, you risk killing brain and liver cells you will never grow back…

When cell division goes wrong…

Cancer can occurCancer is a set of

diseases affecting all parts of the body

ALL SHOW UNCONTROLLED CELL GROWTH

Causes of CancerGENETICS

Cancers tend to run in families

The genes for certain cancers have now been identified: ex – BRCA1+2 for breast cancer

Causes of Cancer

ENVIRONMENT Sunlight Radiation Chemicals▪ Asbestos▪ Formaldehyde

Causes of CancerLIFESTYLE

Diet▪ Fatty Foods▪ Aspartame▪ Plastics

Drugs▪ Tobacco▪ Alcohol

Exercise Stress

EXIT TICKET (get stamped before you leave)

1. What is cancer?2. What is one cause of cancer you

have no control over?3. What are two causes of cancer you

can control?4. List one lifestyle change you are

willing to commit to in order to reduce your cancer risk.

DNA

Have you ever heard of “genes” or “chromosomes”? What are they? If you haven’t, take a guess at what you think they might mean.

What is a chromosome?

What is a chromosome?

DNA is really longA nucleus is really

smallWe need a way to

package it all together…

The solution is a chromosome!

Anatomy of a Chromosome

A chromosome is one molecule of DNA wound up tightly with some proteins.

When replicated, the chromosome looks like an “X”

At the middle of the “X”, there is a joining spot called the centromere

Chromosomes are Cool!

They look sweet under a microscope ….how cool is that?

They are the blueprints for life!

To the left is a human karyotype, an organized arrangement of all the chromosomes in a cell

Humans have 2 sets of 23 chromosomes – one set from mom and one from dad

We call this state 2nEach set of

chromosomes is called 1n

Karyotyping

Karyotypes can be used to look for genetic diseases.

Look at the human karyotype on the left. Remember humans are 2n. Is this human healthy or unhealthy?

This human has trisomy 21, also known as down syndrome

ACTIVITY TIME! Everyone should have received one unreplicated

chromosome from the bag. You are 1n. When the teacher says go, find your chromosome

pair. Your chromosome will be the same size and have the same pattern. You are now 2n.

After you find your match, work with the class to order your chromosomes from largest to smallest across the middle of the floor to create a karyotype.

You have 10 minutes!

EXIT TICKET (get stamped before you leave)

1. What is a chromosome?2. What does 2n and 1n mean?3. When a chromosome replicates,

it forms an “X”. What is the middle of this “X” called?

DNALook at the slide to the

left, and answer the following:What kind of cells are

these (prokaryotic, plant or animal)? How do you know?

Can you identify any organelles? Which ones?

Do all the cells look the same or do they look different? In what ways?

Card ActivityGet in a group of approximately 6 students. There

should be four groups in the class.You will receive a deck of cards. Each card has a

picture of a cell on it.Work with your group to put each card into a category.

You may categorize the cards in any way you choose.If your group members disagree on a card or category,

work together to discuss the issue until you come to an agreement. If you still can’t decide, set the card aside.

You have 15 minutes. We will share our results when time is called.

Reflection QuestionsHow many categories of cells did your group

come up with?How did you decide on those categories?Did all groups came up with the same

number of categories? Why or why not?Is there a single right or wrong way to

categorize these cells? Why or why not?

DNA Find your lab group and sit with

them. Read over the directions for the lab as a group. When you are ready to begin the lab, raise your hands, and the teacher will bring you the materials.

DNA

Sheena spends 30% of her time sleeping, 10% eating, 40% working, and 5% exercising. What percentage of time does Sheena have left to relax?

DNA•GALLERY WALK! Grab your lab

notebook, a writing utensil, and get up from your seat.

•Your classmates’ pie charts are posted around the room. Spend ten minutes looking at the charts and answering the following question:

▫Does all the data look the same or does it look different? List a minimum of two similarities and two differences you see between charts.

The Cell Cycle

Why Don’t Cells Just Get Bigger?

Why Don’t Cells Just Get Bigger?

• Diffusion

• Osmosis

• Active Transport

• Cell Communication

The Cell Cycle

• TWO MAJOR PARTS:• Interphase

▫ Gap 1 phase (cell grows)▫ Synthesis Phase (DNA

replicates)▫ Gap 2 phase (cell preps for

next phase)• Mitosis (M-phase)

▫ Composed of 4 phases▫ Cytokinesis ends M-phase by

pinching the cell into two• There are “checkpoints”

after each phase

How Close Did We Get?

SHH! Mrs. Faller is listening to her iPod. Listen carefully and number your paper #1 - #5.

When Mrs. Faller raises both her hands, answer the question, “Can you hear me now?” Write “YES” next to #1 if you can hear Mrs. Faller’s music and “NO” next to #1 if you can’t hear the music.

We will repeat this procedure four more times. When Mrs. Faller raises her hands again, get ready to collect data for #2.

DNA

Oh, please. It’s not that loud… is it?

The most popular personal music device in the United States is the Apple iPod. Volume is measured with a unit called decibels. The factory volume settings on an iPod can be seen in the table to the right:

Look at the output again…

Decibels (dB) Noise

60 Everyday conversation

80 Heavy city traffic

100 Chain saw, pneumatic drill

110 Dance Club

130 Jet take off

So what’s a decibel?And compare to everyday noise…

Why so dangerous?

Great… so what IS safe?NOTE: This includes

exposure to ALL noise – not JUST your MP3 player. The numbers sound great at first, but don’t forget about all the other “sound pollution” in your life!

Decibel Level (dB)

Length of Exposure (hrs)

90 892 695 497 3100 2102 1.5105 1110 .5115 .25

What happens if I don’t care?

DNA

Which takes longer to complete – interphase or mitotic phase? Why do you think this is so? (consider what is happening during each part of the cycle)

M-Phase (MITOSIS)

Composed of FOUR PHASESPROPHASEMETAPHASEANAPHASETELOPHASE

Prophase

Nuclear membrane disappears

Chromosomes condense

Spindle fibers form

Metaphase

Chromosomes line up along the metaphase plate

Spindle fibers are attached to the centromeres

Anaphase

Chromosomes are pulled apart into their copies, called sister chromatids

The chromatids move away from each other

Telophase

Nucleus forms again

Cell is pinched into two by cytokinesis

Mitosis occurs in somatic cellsSomatic – body (non –

reproductive) cells. These cells are always 2n

Mitosis starts with a 2n state and ends with a 2n state.

The daughter cell is an exact replica of the parent cell

DNA (45 MINUTES) Find a partner to work with. You may work in a

group of three, but NO LARGER. Look over your notes from the mitosis unit. As a pair (or trio), write ten questions you would

expect to see on an exam. You must include at least one of each type of question: Multiple choice True/False Short Answer

Don’t forget your answer key! Make sure all names are on your paper, and turn it

in on your way out.