1. Outside the Nucleus Do Now: Use your lab handout to answer. A student measures the low power field of view of their microscope to be 6.0 mm. A: What is the medium power F.O.V.? B: if about 20 animal cells fit in the medium power field of view, how big is each cell?

2. Medium power FOV Medium FOV = (low power diameter)(low power objective) / (medium power objective) = (6.0 mm)(4) / (10) = 2.4 mm

3. How big are the cells? (Medium FOV) / (# cells) x 1000 = 2.4 mm / 20 x 1,000 µm / mm = 120 µm

4. Label the cell membrane (aka plasma membrane), nucleus, and nucleolus on your diagram

6. About those ribosomes… Very important function: RIBOSOMES MAKE PROTEINS! They can be found in both eukaryotic & prokaryotic cells

8. Steps in Protein Production An RNA copy of DNA is made in the nucleus A type of RNA called mRNA moves out of the nucleus into the rough endoplasmic reticulum (RER) Ribosomes attached to the rough ER use the mRNA instructions to build a protein The protein moves to the smooth ER for further processing. The smooth ER houses other chemical reactions too.

9. Homework: CELL OBSERVATION LABS DUE TOMORROW!