Opening Activity: Feb. 27, 2017 Welcome Back! Share with your table how you experienced science during your break. Review your “Cell Cycle and Growth” reading. What is the purpose of mitosis?’ How are replicated chromosomes held together? A cell with 46 chromosomes goes through mitosis how many daughter cells will there be? How many chromosomes will each daughter cell have? Homework: Cell Cycle Quiz – 3/2 DNA, Cell Division & Differentiation Test –Wed 3/8 I can… Explain what happens to DNA during cell division.

Today’s Goals 1. Lab #12 Part B, Pipe Cleaner Models. This is what one of each means: Write answers in journal 3. Check Planaria.

Opening Activity: Feb. 28, 2017 Check out the Slide, what stages of cell cycle is A B C I can… Review cell division and reflect on learning so far. Homework: Cell Cycle Quiz – 3/2 DNA, Cell Division & Differentiation Test –Wed 3/8 DNA Quiz Make up HR Tues-Fri

Opening Activity: March 1, 2017 Find your Review sheet/Idea journal – is your name on it? I will stamp your first row. Complete the second entry, Cell Division. I can… Explain how cells can have the same DNA but have different functions. Homework: Cell Cycle Quiz – 3/2 DNA, Cell Division & Differentiation Test –Wed 3/8 DNA Quiz Make up HR Tues-Fri

The right gene at the right time Cell Differentiation The right gene at the right time

Key Questions… How do cells know what type of cell to become? How do they coordinate to form tissues, organs, and a complete organism?

Opening Activity: March 2, 2017 I will come around and stamp questions from cell differentiation activity. As a group, look at your cells from yesterday. Identify one gene that is found in all cells. Why do you think ALL cells expressed the gene? What gene is expressed in a skin cell but NOT a muscle cell I can… Explain how cells can have the same DNA but have different functions. Use data to describe what happened to the planaria over time. Homework: DNA, Cell Division & Differentiation Test –Wed 3/8 DNA Quiz Make up HR Tues-Fri

Planaria Wrap up Take final measurements and observatations. Record data and observations in journal. Calculate changes in length over last 3 weeks. Record data on class data table. Return Planaria to the “Recovery Container”. Return petri dishes to front tub. Pick up Evidence-Based Argument Tool at front bookshelf and tape in.

Opening Activity: March 2, 2017 Review your planaria data from yesterday. Discuss at your table how you calculated the changes in length for your planaria. Circle the total changes you saw in A, B and C. Ms. Fox will stamp your data. Find your Planaria EBA Tool – Tape in. Complete the “Class Evidence”Column. I can… Use data to describe what happened to the planaria over time. Explain how cells can have the same DNA but have different functions. Homework: DNA, Cell Division & Differentiation Test –Wed 3/8 DNA Quiz Make up HR Tues-Fri

What makes the different types of cells in your body unique? Muscle cells and neurons in your body have the same DNA, but they express (use) different genes. Gene expression causes cells to look unique and to perform different functions.

Stem Cells vs. Differentiated Cells Differentiated cell = Specialized cell (neuron, muscle) Stem cells are cells that have not yet differentiated into a specific cell type. Stems cells can be turned into differentiated cells by turning on and off particular genes.

When do cells differentiate? During development (embryonic stem cells) Zygote to embryo to fetus to infant Over your life as cells are replenished (adult stem cells) Examples: Blood cells are replenished Intestinal cells are shed and replaced More on this later today!

Development and Differentiation Key questions: How do cells know what type of cell to become? How do they coordinate to form tissues, organs, and a complete organism? Answer: Cells must communicate through signals to coordinate development.

Example: Body plan formation (head vs. tail) Cells develop differently in the head and the tail, and in other positions of the planaria’s body Communication between cells is important in multicellular organisms for body pattern formation