EDISON G AGORAM MEMORIAL SCHOOL, MANALUR,CHIDAMBARAM

CLASS: X BIOLOGY PRACTICAL MANAUL

1. Preparing a temporary mount of a leaf peel to show stomata

Aim
To prepare a temporary mount of a leaf peel in order to show the stomata of a leaf
Material Required
• A potted plant of Bryophyllum or Tradescantia, Needles,Forceps,Watch
glass,Dropper,Glass slides,A brush,Coverslips,Blotting paper,Safranin,Compound
microscope,Glycerine
Procedure
• Pick a healthy leaf from the potted plant
• Fold the leaf to gently pull the peel apart to separate a peeled section from the lower
surface of the leaf. Use the forceps to perform this step. Allow the peel to remain in a
watch glass holding water for some time.
• In the watch glass, stain the sample by adding some drops of safranin through a dropper.
• Take the peel out after 2-3 minutes. Set it on a clear glass slide
• Add a drop of glycerin on the peel. Put a clear coverslip over it gently using a needle.
• Excess glycerin and stain can be removed using blotting paper
• Examine the slide first under a low-power and then under a high-power magnification of
a compound microscope.
Observation
• Visible epidermal cells. The cells in their outline are irregular with no intercellular
spaces
• Small openings, stomata are scattered through the epidermal cells
• Guard cells are observed which have chloroplasts and nucleus
• Guard cells are observed having a thin outer covering and a thick inner
boundary(concave)
• Guard cells control the closing and opening of the stomata.
Result
Epidermal cells are found containing stomata on the lower surfaces of the leaf.
2. EXPERIMENT TO SHOW THAT CARBON DI OXIDE IS EVOLVED DURING
RESPIRATION

Aim
To experimentally demonstrate that carbon dioxide is released during the process of respiration.
Material Required
• Soaked gram seeds,U-shaped delivery tube,Conical flask,Blotting paper (moist),cotton
wool,Thread,Water,Beaker,Test tube,Rubber cork with a single hole,Freshly prepared
KOH solution (20%),Vaseline
Procedure
• Germinate close to 25 seeds. This can be done by wrapping them in moist blotting paper
or cotton wool for around 3 to 4 days.
• Set up the germinated or sprouted seeds in the conical flask. Spray some water into the
flask to dampen the seeds.
• With the help of a thread, suspend the conical flask containing the test tube having a
freshly prepared 20% KOH solution.
• Use the rubber cork to seal the opening of the conical flask.
• One edge of the U-shaped glass delivery tube present in the conical flask should be
inserted through the hole in the rubber cork. The other edge should be placed into a
beaker that is saturated with water.
• All attachments of the set-up should be sealed. This can be done using vaseline to create
an air-tight environment.
• The initial water level present in the U-shaped delivery tube needs to be marked.
• Leave the experimental set-up uninterrupted for 1 to 2 hours. Observe the fluctuations in
the water level in the tube.
Observation
Careful observation after a certain period of time reveals that the water level in the U-shaped
delivery tube has risen in the beaker.
Result
The rise in level water indicates that carbon dioxide is released as a result of germinating gram
seeds during the process of respiration in the conical flask. The carbon dioxide that is released
in the process is absorbed or consumed by the KOH solution that is suspended in the test tube
in the conical flask, creating a vacuum or a void in the flask resulting in the upward water
movement in the tube. Hence, the water level in the tube changes.
Precautions
• The seeds that are to be germinated need to be moistened
• Air-tight environment for all the connections in the experimental set-up
• The KOH solution that is used needs to be freshly prepared
• Care needs to be taken to ensure that one end of the delivery tube is placed in the conical
flask. The other edge is submerged in the water of the beaker
• The tube that contains the KOH solution needs to be suspended carefully
3. Studying binary fission in amoeba and budding in yeast with the help of prepared slides
Aim
To study about (a) Binary Fission in amoeba and (b) Budding in yeast with the help of prepared
slides
Material Required
• Compound microscope
• Permanent slides of budding in yeast and binary fission in amoeba
Procedure
• Place the slide under a compound microscope
• Focus the slide, first under low power and later under high power of the compound
microscope
• Various stages of budding and binary fission can be carefully examined
Observation
(a) Binary fission in Amoeba
• Initially, the pseudopodia are retrieved. The body of amoeba is coiled and becomes
round
• Amitosis is observed, the division of the nucleus takes places which are followed by
splitting of cytoplasm
• At the point of fission in the body of the amoeba, a construction starts to develop.
• The constriction or furrow turns deeper resulting in the formation of two daughter cells
(b) Budding in yeast
• Protuberance or a tiny outgrowth is observed on the parent cell
• Division of the nucleus is observed which is later seen in the bud
• Repetitive budding leads to the formation of a chain of cells
(c) Buddin in Hydra
• Budding is a type of asexual reproduction
• In hydra, a bud develops as an outgrowth due to repeated cell division
• Now the nutrition for bud growth is provided by the parents hydra.
• The development showed by bud starts to develop small tentacles and a mouth.
• A full- grown bud detaches from the parent body and becomes an independent organism.
BUDDING IN HYDRA
4. Identification of the different parts of an embryo of a dicot seed
Aim
To identify the different parts of an embryo of a dicot seed
Material Required
• Seeds of red kidney bean/gram,Forceps,Magnifying glass,Cloth,Petri dish,Water
Procedure
• Soak a few seeds overnight
• Next morning, drain the excess water out
• Now wrap the seeds in a clean and a moist cloth for a day, allow it to dry
• Next, carefully peel the seed coat
• With the help of forceps, dissect the seed so as to get two equal halves
• Examine with the help of a magnifying glass. Carefully identify and locate different
parts of the seed
• Sketch out the interior of the seed you examined labeling all the parts as shown in the
diagram.
Observation
• The bean seed resembles the shape of a kidney. It has a convex and a concave side
• A scar known as the hilum is observed on the slightly darker side of the concave side
• A tiny pore known as the micropyle is located just adjacent to the hilum
• The seed is enclosed by a seed coat
• The embryo possesses two distinct and large cotyledons that resemble the shape of a
kidney and are white in color
• Lateral attachment of the cotyledons to the curved embryonal axis is observed
• Radicle is examined. It is the rod-shaped and lightly protrusive lower end of the
embryonal axis that is found placed towards the micropylar end.
• The upper end of the embryonal axis exhibits the plumule
• Hypocotyl is observed which is a section of the embryo axis found in between the
radicle and adjunct of cotyledon leaves
• The epicotyl is also observed which is the section of the embryo axis between the
adjunct of cotyledon leaves and plumule
Result
Three principle parts of the embryo of dicot seeds are observed, they are:
• Cotyledons
• Plumule
• Radicle