The Cell and the Microscope. Chapter 2. 23/11/12

Recap!!

Recap!! How did you set up the investigation to observe an animal cell. What did you see when you looked under the microscope. How do draw an animal cell. What labels do you put on the diagram. Mind map for the characteristics of life.

Eyepiece lens Coarse focus barrel Fine focus Objective lens slide stage Iris diaphragm

By the end of this class: You will be able to: Set up an investigation to observe a plant cell. Identify a plant cell under magnification. From your observations draw and label a diagram of a plant cell. List the functions of the cell.

Lab Safety!! Sitting in seats; bags out of way of walkway. In lab NO drinking or eating in the labs. Wear goggles. If anyone breaks glass inform teacher immediately!

Equipment Needed: Per Pair: Microscope slide. Dropper. Cover slide Tissue Paper. Microscope. Iodine for plant cells.

Method: Step 1: Get an onion, with a forceps peel a thin inside layer from the onion. Step 2: Place the slice of onion on the slide carefully. Make sure it doesn't fold on top of itself. (Needs to be flat)

Method: Step 3: With the dropper place one drop of water on the plant cells. Step 4: With your tissue paper gently place it to the side of the plant cells to absorb the extra water.

Method: Step 5:Place one drop of iodine directly on to the plant cells. Step 6: Putting on the cover slide: Starting at one edge, gently lower a cover slip over the onion skin

Method: Step 7: Place the slide on the stage under low power(X4). Use the coarse adjustment knob to focus Step 8: Rotate the nosepiece to medium power (X10). Use the fine adjustment knob to focus. Observe what you see.

Tidy up!!

Draw What You See: Under the different magnifications: and draw what you see (use a pencil!!)

Plant Cells Image was at X400 magnification.

Plant Cells labelled:

WRITE UP!!! Into your Experiment book!! Under these headings!! Title: To examine plant cells under a microscope Equipment Method (How did you set up the experiment) Diagrams Result (Q. At what magnification was there a clearer image) Conclusion (What could you see?)

Functions of the part of the Cell!! Cell Membrane: controls what enters and leaves the cell.

Functions: Nucleus: is the control centre of the cell, it contains our genes(DNA).

Functions: Cytoplasm: is a watery fluid found between the nucleus and the cell membrane.

Typical Plant Cell

Function Cell Wall: Only plant cells have a cell wall. The Cell Wall is made of a firm substance that gives shape and support to the cell.

Recap!! How did you set up an investigation to observe a plant cell? What did you see when you put the slide under magnification? What labels did we put on your diagram? List the functions of the parts of the plant cell?

Homework!!