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Virtual Lab – Microscopy – Plant Cells (Onion Epidermal Cells) In plant cells such as Elodea cells, chloroplasts are typically present. However, onion cells often lack chloroplasts. This is because onions are storage organs that do not perform photosynthesis; instead, they store nutrients. Elodea, being a green aquatic plant, needs chloroplasts to perform photosynthesis, so it contains them.

Virtual Lab – Operation of Bright Field Microscope How does changing light intensity affect the contrast of an image in a microscope?

Virtual Lab – Osmosis – Tonicity in Elodea Cells (Plant Cells) When solute concentration is lower in an environment compared to the other side of the membrane, it is known as a _____________ environment.

Virtual Lab – Diffusion Across a Selective Permeable Membrane How do we test for the presence of starch using iodine (IKI)?

Virtual Lab – Microscopy – Plant Cells (Onion Epidermal Cells) Follow the steps provided in the reading section of this study guide for assistance to calculate the estimated width (in

Virtual Lab – Operation of Bright Field Microscope What is the difference between resolution and contrast?

Virtual Lab – Operation of Bright Field Microscope What is the relationship between objective, magnification power and the field of view?

Dialysis tubing is a selectively permeable membrane made with the macromolecule, cellulose. Starch, glucose, water and the IKI reagent arecontained within the dialysis membrane in solution B shown below. Solution A in the beaker, at the start of the experiment in panel (a) contains just water. Diffusion of these molecules occurs, over time, from panels (a)-(c). The only selective criterion for diffusion across a dialysis membrane is the size of the molecule. Which of these molecules will diffuse the fastest? 

Virtual Lab – Diffusion Across a Selective Permeable Membrane Diffusion is a passive process that moves substances from an area of [word1] concentration to an area of [word2] concentration.

Virtual Lab – Microscopy – Wet Mount (Euglena) What organelle assists the Euglena in osmoregulation?