Depth paper notes Flashcards
Ways the images produced by LSCM and Electron microscope differ
LCSM: lower resolution, fluorescent tags, can see movement of living cells
Xylem and phloem similarity
Both xylem and phloem are made up of cells joined end to end
Differences between xylem and phloem
Xylem = lignified cell walls, no sieve plates
Phloem = non-lignified cell walls, has sieve plates
Dissection of bony fish
Dissection of bony fish:
-Removal of operculum
-Dissect underwater, place rod in buccal cavity to display lamallae, stain tracheoles with methylene blue
Insect dissection
Dissecting insects:
-Removal of exoskeleton
Difference of treacheae of insect and of mammal
Insect trachea = multiple tracheae, smaller diameter, made up of chitin, spiral support, shorter, branches into tracheoles
Mammal trachea = one trachea, alrger diameter, c-shaped cartilage rings, larger, branches into bronchi
Alveoli adaptations for efficient gas exchange
Alveoli adaptations for efficient gas exchange:
-Large sa:vol ratio for increased diffusion rate
-Thin walls that are once cell thick for shorter diffusion pathway
-Good blood supply ->maintains a concentration gradient
-Well ventilated -> oxygen constantly being replenished and co2 constantly removed
-Elastic fibres - strretch and recoil
stretch -> increases surface area
recoil -> helps force air out
How callibration curves are used to estimate glucose concentration
How callibration curves are used to estimate glucose concentration:
-Find absorbance using colorimeter
-Find concentration that corresponds to the absorbance on the callbration curve on graph
Two similarities of cholesterol and glucose molecular structure
Both cholesterol and glucose contain C and H atoms, and has OH groups
Physical property of glucose that allows it to be transported in the blood stream
Physical property of glucose that allows it to be transported in the blood stream: glucose is soluble in water
Cell found in phloem that contains sap
The sieve tube cell in the phloem contains the sap
Why can starch not be transported in sap?
Starch cannot be transported in sap because it is insoluble
Importance of differential staining
Importance of differential staining:
-Different organelles can be seen
-Different cells can be seen
-Allows for contrasting
-Allows white blood cells (with are otherwise transparent/colourless)
Difference of characteristics within a population
Intraspecific variation
Potometer precautions for setting up and during the procedure
Potometer:
-Ensure it is watertight/airtight
-So no bubbles enter
-Cut stem underwater
-Use apparatus under water
-Use syringe to move bubble -> doesn’t move too far/doesn’t enter xylem/same bubble can be re-used
Reasons for anomolies
Anomolies:
-Misread scale
-Times for longer
-External condiitons eg temp increase
Why is capillary tube useful in measuring transpiration?
Capillary tube is useful in measuring transpiration because:
-Small diameter -> distance is greater/easier to measure
Disaccharide examples
-Starch -> disacharide + non reducing sugar
-Lactose + Malstone -> disacharides + reducing sugars
Testing for haemoglobin
Testing for haemoglobin:
-Biuret reagent
-Colour change (blue -> purple)
-Compare with a control
Measuring glucose concentration without a colorimeter
Measuring glucose concentration without a colorimeter:
-Benedicts strips or biosensor
-Observe colour change
Biosensors
Biosensors analyse concentrations of substances within solutions eg glucose
How to callibrate a colorimeter before measuring glucose concentration
Callibrating a colorimeter:
-Red filter use
-Use known concentration
-Serial dilution
-Cuvette used with transparent slides
-Use of distilled water -> sets it to zero
Cilliated epithelial cells locations
Cilliated epithelial cells locations:
-Trachea
-Bronchi
-Bronchioles
-Lungs
Investigating cell membrane permeability -> effect of temperature on beetroot membranes
Effect of temperature on beetroot membranes:
1). cut 5 equal sizes and rinse to remove excess pigment released whilst cutting
2). add 5cm^3 of water to each
3). Use of water baths with varying temperatures and use stopwatch
4) carry out colorimetry
5). higher the permeability -> more pigment release -> higher absorbance
