Post on 05-Jan-2016
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Mitosis
Catalyst:How do organisms grow?
What happens during interphase?Write in complete sentences!
Don’t talk during the Catalyst!
Objectives
By the end of the period, SWBAT…
Describe the five phases of mitosis
Explain why mitosis produces two identical cells
Definitions – In case you missed them… Sex cells = sperm and egg cells Somatic cells = all other cells in your body
DNA = genetic code that instructs the cell how to run (it’s what makes you “you”)
Chromosome = pieces of coiled DNA. They look like Xs.
Catalyst Review
How do organisms grow? They create new cells! One cell divides into two The new cell is an exact copy of the previous cell
This process is called mitosis
Catalyst Review
What happens in interphase? Cells do their normal cell things
Heart cells beat Plant cells photosynthesizeEye cells let you seeSkin cells protect you from stuff
outside your body When cells are ready to divide, make
an exact copy of their DNA
Catalyst Review
Remember… Somatic (body) cells normally have 23 pairs of chromosomes2N = 2 PAIRS
When they are ready to divide, they make copies of their DNA4N = 4 PAIRS
Mitosis CHALLENGE! Are you up for it?
Arrange the four pictures in order that makes sense to you and your group!
There will be a prize for the group that gets the correct answer AND can explain why they chose this order.
Remember: In mitosis, a somatic cell creates an exact copy of itself.
Stage #1: Interphase
Normally cells are 2N (two copies of each chromosome)
When cells are ready to divide, the cell’s DNA doubles Cell becomes 4N
(four copies of each chromosome)
Chromosome Pairs
In interphase, chromosomes duplicate and form pairs
When a chromosome is in a pair, it is called a chromatid
Stage #1: Interphase 2N
Phase #2: Prophase
Sister chromatids attach to each other
Centrioles move to opposite ends of the cell
Nuclear membrane breaks Allows chromatids to move
freely
4N
Sister chromatids line up in the center of the cell (“metaphase plate”)
Spindles shoot out of centrioles, and attach to sister chromatids
WHY would sister chromatids line up at the metaphase plate?!?!?!
Phase #3: Metaphase 4N
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Phase #3: Metaphase
Spindles pull sister chromatids apart to opposite ends of the cell
WHY would sister chromatids move to opposite ends of the cell?!?!?!
Phase #4: Anaphase 4N
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Phase #4: Anaphase
Nuclear membrane reforms
Spindle breaks apart
Cleavage furrow forms, “pinching” the cell in half
WHY would the cleavage furrow split the cell in half?!?!?!
Phase #5: Telophase 4N
Phase #1: Interphase
Now we have two identical cells!!!
2N
Animal Cell Plant Cell
Photographs from: http://www.bioweb.uncc.edu/biol1110/Stages.htm
Phase #5: Telophase
Animal Mitosis: Review
Interphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
Plant Mitosis: ReviewInterphase
Prophase
Metaphase
Anaphase
Telophase
Interphase
WOW MR. LY YOU RULE!!!
THANKS MR. LY FOR THE SWEET MOVIE!!!
IInterphasePProphaseMMetaphaseAAnaphaseTTelophase
II PPaintaint MMany any AAmazingmazing TT--shirtsshirts
WHO’S PAYING ATTENTION?
What type of cell does mitosis occur in?
What is the starting point of mitosis?
What are the end products of mitosis?
What are the names of the stages of mitosis?
Guided Practice
Today, we will move around the classroom to answer questions on the board. You have 10 seconds to get to each spot. In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Chromosomes line up in the middle of the cell
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Cleavage furrow forms, pinching the cell in half.
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
In between cell divisions, when the cell does its thaaaaang.
Which phase is this?
In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
When chromosomes are pulled to opposite sides of the cell.
Which phase occurs AFTER this? In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Chromatids attach to each other and centrioles begin to move to opposite sides of the cell.
Which phase occurs AFTER this? In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Chromosomes line up in the middle of the cell.
Which phase occurs AFTER this? In the middle of the classroom – Interphase By the door into the classroom – Prophase By the stereo – Metaphase By the computers – Anaphase By the college poster – Telophase
Chromatids are pulled apart to opposite sides of the cell.
Conclusion
I Paint Many Amazing T-shirts! Prophase – chromatids attach to each
other Metaphase – chromatids line up in the
middle of the cell Anaphase – chromatids are pulled to
opposite ends of the cell Telophase – cleavage furrow forms and
pinches off two cells Mitosis ends up with two identical
cells!
Exit Question
What are the phases of mitosis in order?
What must occur before mitosis (think DNA)? Write in complete sentences!
Don’t talk during the Catalyst!