Required Practicals Flashcards
What is the microscope practical?
Set up microscope and observe cells like cheek cells, onion cells algal cells
Remember to place the slide carefully on the stage and clip it with cells on
Then bring the objective lense down, watching from an outside view to ensure the lense doesn’t touch the slide
Then, once stable, use the course focus dial to slowly bring the cells into focus when looking into the eyepiece
When in focus, use the fine focus dial to get gem in total focus
You will not see ribosomes
What is the osmosis practical?
Make model cells using bags made of partially permeable membrane
Place bag in various sugar solutions and view what happens when the solution is hypotonic to the cell or hypertonic
Observing cell practical
Place roof top under microscope- should be able to see the membrane disappear and this two chromosomes should divide into identical nuclei
What is the food groups practical?
Add iodine to carbohydrates to see if starch is present- solution will turn blue/ black
For carbs, you can also add Benedicts solution which turns red if glucose is present when heated
for protein, biuret test- turns purple if protein is present
For lipids- ethanol test- a cloudy white layer appears
What is the Ph on amylase practical?
Palace several starch solutions of a known volume into water bath, not higher than 37C
Add a buffer solution at a different Ph to each starch solution
Set ups potting field and drop iodine on each spot
Observe colour change
Protein enzyme practical
Get three test tubes and place pepsin, HCL and a mix into yeh tubes
Add meat
Observe results
Blood flow practical
Find pulse on your neck and veins
Evidence for movement through xylem practical
Place celery sticks in water containing coloured dye- a few hours later, slice it in half, you will see coloured circles when the water and dye have moved through the xylem
Culturing microorganisms practical
Sterilise Petri dishes
Sterilise Agar
Glass dishes sterilised
Using an inoculating loops which you sterilise on fire, add the bacteria
Add lid with tape
Incubate dishes for a few days- store upside down so condensation doesn’t fall from lid to agar surface
Disinfectants and antibiotics practical
When culturing- add different circles of disinfectant or antibiotic. Clear area of Agar jel shows the microorganism have not cultured- measure the zone of inhibition
Producing oxygen practical?
Use water plant- bubbles will appear showing the by product of oxygen involved in photosynthesis
Light intensity and rate of photosynthesis practical
Use water plant and place light closer to it- see how many bubbles produced
Then move further away and observe effect on bubbles
Showing starch in leaves
Take two leaves- one from plant left in light for 24 hours and one from pant left in dark for 24 hours
Boil leaves in ethanol to destroy waxy cuticle and remove colour
Rinse in hot water to soften them
Add iodine solution to both leaves
The one in the light should turn blue due to photosynthesis producing glucose which is then stored as starch
Investigating respiration practical
Blow into straw which is places in a beaker containing limewater- the limewater should go cloudy as it goes cloudy when carbon dioxide bubbles through it
Testing fitness practical
Measure heart rate and breathing rate of people that do exercise vs those that do not
