Lab Quiz 3: Week of Sept 22 (cell structures and functions, iso/hypo/hypertonic solutions)

Plasma membrane

Protective barrier, regulates what enters/exits the cell, cell signaling.

Solute

the substance that is dissolved

Solvent

the substance in which the solute dissolves

What was the selectively-permeable membrane in the osmosis experiment?

Dialysis Tubing

What were the selectively -permeable membranes?

plasma membrane, tonoplast

which dialysis bag had the largest increase? Why?

Bag 3, water moved into the bag because it had a higher sucrose concentration (bag: 30% sucrose, beaker: DI water)

Which bag decreased?

Bag 4, water moved out of the bag because it had a higher concentration of sucrose OUTSIDE of the bag causing water to leave the bag (Bag:Distilled water, beaker: 30% sucrose)

Two main differences between eukaryotic and prokaryotic cells

Prokaryotic=no nucleus, eukaryotic= mitochondria and ER (prokaryotic don't have)

diffusion and osmosis are BOTH

Both examples of passive transport.

Cytosol

Internal substance of the cell, site for chemical reactions.

Nucleus

Houses DNA.

Nucleolus

Ribosome unit assembly.

Mitochondria

ATP synthesis.

Rough endoplasmic reticulum

Synthesizes proteins.

Smooth endoplasmic reticulum

Synthesizes lipids and steroids.

Golgi body

Protein packaging and sorting.

Nuclear envelope

Surrounds nucleus.

Nuclear pores

For nuclear traffic.

Chromatin

DNA and associated proteins, contains genetic information.

Lysosome

Breaks down excess material.

Centriole

Forms centrosomes for cell division.

Microtubules

Moves/organizes cells and materials.

Ribosomes

Protein biosynthesis.

Chloroplast

Responsible for photosynthesis.

Vacuole

Responsible for storage of waste, nutrients, and water.

Cell wall

Surrounds the cell for structural and mechanical support.

Nuclear traffic

Movement of materials through nuclear pores.

Cytoplasmic streaming

Important for transporting essential nutrients throughout larger cells.

Higher power of magnification

Used to observe smaller structures like vacuoles or nuclei.

isotonic solution

a solution whose solute concentration is equal to the solute concentration inside a cell. Experiment: 0.9% NaCl (concentrations of blood cell and NaCl were the same)

hypertonic solution

Solute concentration is greater than that inside the cell; cell loses water. Experiment: 10% NaCl, had more concentration outside of the cell (shrinks)

hypotonic solution

Solute concentration is less outside but greater inside the cell; cell gains water to dilute it. Experiment: DI water, had less solute concentration than the blood cell.

Osmosis

Movement of WATER through a selectively permeable membrane from low to high concentrations

Diffusion

Movement of SOLUTE from an area of higher concentration to lower concentration.

Structures found in plant cells but not animal cells

cell wall, chloroplast, central vacuole

Found in animal cells but not plant cells

centriole

Found in prokaryotic cells

DNA, cytosol, ribosomes, cell wall

What 3 different shapes of bacteria did we observe?

Coccus, bacillus, spirillum

how to make a wet mount slide

• Clean microscope slide

• Add one drop of specimen

• Place a clean coverslip

• 45 degree angle at edge of the sample

• Release cover slip slowly

• Remove excess liquid with paper towel

• Do not allow liquids to touch the objective lens

of the microscope!

Elodea Hypotonic Cells

Cells swelled up but didn't burst due to cell wall

Red blood cells in hypotonic solution

cells swell and burst, no cell wall

osmotic lysis

rupture of the plasma membrane resulting from movement of water into the cell

Plasmolysis

This happens when a cell shrinks inside its cell wall while the cell wall remains intact.

Tonicity

the ability of a surrounding solution to cause a cell to gain or lose water

What organelles are responsible for the changes that you see in the Elodea cells?

Plasma membrane, chloroplasts, vacuole

What kind of blood did we study?

Sheep Blood