lab 5: cell structure

methylene blue in slide preparations

increase contrast and visibility of cell structures

how do bacterial cells (prokaryotic) differ from eukaryotic cells (plants, animals)

prokaryotic cells do not have membrane bound organelles or a membrane bound nucleus, whereas eukaryotic cells do

what is common to both prokaryotic and eukaryotic cells under microscopic examination

plasma membrane and cytoplasm

what are the green, oval objects visible around the perimeter of the cell

chloroplasts

what are onions plastids called

leucoplasts

what plastids do carrots have

chromoplasts

describe the major structural differences between plant and animal cells

plant- rigid cell walls to maintain shape, contain chloroplasts, fixed rectangular shape.

animal- do not have cell wall. lack chloroplasts, often round or irregularly shaped

osmosis

type of diffusion that refers to the movement of water molecules from a region of high water concentration to one of lower water concentration across a semipermeable membrane

diffusion

the movement of materials from a region of high concentration to a region of lower concentration

solute

A substance that is dissolved in a solution.

solvent

A liquid substance capable of dissolving other substances

solution

A mixture that forms when one substance dissolves another.

what factors influence the rate of diffusion

temperature, concentration gradient and molecular weight of the solute

facilitated diffusion

process of diffusion in which molecules pass across the membrane through cell membrane channels

tonicity

the relative conventration of solutes in two fluid environments

isotonic solution

A solution in which the concentration of solutes is essentially equal to that of the cell which resides in the solution

hypertonic solution

A solution in which the concentration of solutes is greater than that of the cell that resides in the solution

Hypotonic Solution

A solution in which the concentration of solutes is less than that of the cell that resides in the solution

Plasmolysis (plant cells)

The pulling away of the cytoplasm and plasma membrane from the cell wall due to lack of water

does simple diffusion require energy

No, it is a passive transport

5.0% saline solution is _____ to blood cells

hypertonic

0.85% saline solution is _________ to blood cells

isotonic

distilled water is ______ to blood cells

hypotonic