Transcript
Chemicals needed for experiments
1. Sodium hydrogen carbonate
When sodium hydrogen carbonate dissolves in water , it supplies the water with
carbon dioxide.
NaHCO3
-------------- NaOH +co2
It is used as source of co2 for photosynthesis.
2. NOTE. The combination of sodium hydroxide and pyrogallic acid (sodium
pyrogallate) absorbs oxygen and carbon dioxide from the atmosphere. Sodium
hydroxide absorbs only carbon dioxide
Sodium pyrogallate is needed to prove that o2 is originating from experiment not
from any other reason.
It is also used to prove that o2 is needed for germination.
3. Iodine solution for starch test .in the presence pof starch turn natural brown color
of iodine solution to blue black color.
4.
a solutions of methylene blue or potassium permanganate will
5.
Lime water: co2 can turn lime water milky.thats why it is used in some experiment.
2 Lime water going milky is evidence of the presence of carbon dioxide. Respiration
involves the breaking down of carbohydrates to carbon dioxide. The production of
carbon dioxide thus supports the contention that respiration is taking place.
3 If a simple chemical reaction was producing carbon dioxide it should be produced
in tube B as well as in tube A, assuming that the chemicals in yeast had not been
decomposed by temperatures as low as 100 °C.
Feature
Seed
Leaves
Root
Monocotyledons
Seed containing one
cotyledon
Leaves containing parallel
veins
Fibrous root system
(adventitious)
Graph plotting
Dicotyledons
Seed containing two
cotyledons
Leaves containing branched
veins
Tap root system with lateral
Draw a line graph unless there is a good reason for doing otherwise(i.e. not bar charts, histograms)
Identify the independent variable-the one that is changed or manipulated.
Identify the dependant varaible-the one that is measured-on which the readings are made.
use a sharp 2B or HB pencil
Horizontal(X) axis should show the Independant variable
Vertical(y) axis should show the dependant variable-the readings made
use a simple scale
Fill at least 2/3 or 1/2 the graph paper, but don't spill off the edges.
label the graph(eg. The temperature on rate of reaction or Graph of rate of reaction(y-axis) against time(x-axis)
label the axes and give the units(based on the table of data)
Ringed dots or crosses to plot the points
If the shape of the curve is not very clear, then draw a line of curve of best fit.
1.
if there is a relationship between the variables, draw a line of best fit/curve
2.
If you are not sure of the relationship between the variables and you do not need to extrapolate, then join the successive points with straight
ruled lines.
3.
if you need to extrapolate or read the values from the graph, you should draw a line of best fit/curve
Otherwise, draw the dots accurately with ruled straight lines.
Bananas reproduce by suckers, not from seed. They cannot disperse themselves, so the "natural method" of dispersal would be by humans taking them from one
place and planting them in another.
Bananas do spread a bit from their base, but without proper attention in keeping weeds and jungle down and hacking out old "trunks" they get swallowed up or
degenerate. Recent guests of ours from Malaysia insisted the plaintain variety grows wild and uncultivated there. Perhaps this is true, but we doubt it; these were
city folk.
