EXPERIMENT 3.1 EXPERIMENT 3.1
PREPARING A SLIDE OF PLANT TISSUES PREPARING A SLIDE OF PLANT TISSUES OBJECTIVES
OBJECTIVES
1.
1. To make To make a thin slice a thin slice by using by using hand-cutting methodhand-cutting method 2.
2. To prepare, sTo prepare, stain and tain and make a amake a aslide of planslide of plant sapmlet sapmle 3.
3. To illustrate To illustrate the obsthe observation oervation of plant f plant samplesample
MATERIALS MATERIALS
Samples Samples A young dicot A young dicot Apparatus Apparatus
Compound microscope Compound microscope Slide and coverslip Slide and coverslip Chemicals Chemicals Eosin Eosin METHOD METHOD 1.
1. About 2 cm oAbout 2 cm of a young root of a young root of balsam is obtained. f balsam is obtained. It is placed on It is placed on microscopemicroscope slide or plate
slide or plate 2.
2. 2. The root 2. The root is cut vis cut very thin througery thin through the regioh the region of maturationn of maturation 3.
3. The thinnest secThe thinnest section is selected tion is selected and it is transferred to and it is transferred to a slide that contain a slide that contain aa drop of water.
drop of water. 4.
4. The slide is obsThe slide is observed by usinerved by using compound micrg compound microscope. The obsoscope. The observation iservation is sketched and labelled in the space provided in Table 3.1
sketched and labelled in the space provided in Table 3.1 5.
5. The tissue The tissue system in system in young root young root system; vassystem; vascular cylinder cular cylinder is identified.is identified. 6.
EXPERIMENT 3.2
PREPARING A SLIDE OF INSECT TISSUES OBJECTIVES
1. To make a slide by using squash technique
2. To prepare,stain and make a slide on insect sample 3. To illustrate the observation of insect sample.
MATERIALS
Sample
A male locust (Example: locust, Valanga nigricornis)
Apparatus
Dissecting and compound microscope Slide and cover slip
Small dissecting dish Pin
Glass rod
Hotplate or Bunsen burner Filter paper
Chemicals Acetic-orcein
METHODS
1. A freshly killed male locust was pinned out on a small dissecting dish with dorsal side uppermost. The wings were pinned out on each side.
2. The abdomen was opened up by a mid-dorsal longitudinal cut. The body wall was pinned back.
3. The testis was identified by using a dissecting microscope. Together with fat, these made up an oval body lied above the gut in abdominal segment (segments 5 and 6). The testes were transferred on a microscope slide.
4. The fat (yellow) was removed as much as can, only the white tubules of the testes were leaved. Two or three were sufficient.
5. Several dropped of acetic-orcein stain was added and was put on cover slip. 6. Then, was covered with filter paper and was squashed gently. This helped the
chromosomes spread.
7. The slide was warmed up on a hot plate or Bunsen burner for about 10 seconds for the staining intensified.
8. The slide was observed using microscope, and specimen was sketched. A photo was taken using digital microscope. The stages of meiosis were examined. Chromosomes were drew and labeled in Table 3.2.
The slide was washed with a jet of water for the excess dye removed, then air dried the material once again and was mounted in Canada balsam or similar media.
DISCUSSION
In Experiment 3.1, we have to make a thin slice of plant tissue sample (Canada balsam) by using hand-cutting method and we also have to prepare it as a slide that to be observed under light microscope. During the
experiment, we took two part of the plant, which are soft stem and root. We chose soft stem as the sample because it makes the cutting method to be easier. As a result, we can observe the structure of xylem and phloem in both part of the tissue.
The characteristics of water-carrying cells(xylem) are it is in the middle of the cell. The xylem of most vascular plants included tracheid, tube-shaped cells that carry water and minerals up from roots. Furthermore, food-carrying cells(phloem) placed at the outer layer of the cell. The phloem has cells
arranged into tubes that distribute sugars, amino acids, and other organic product. Roots are organs that absorb water and nutrients from the soil. Roots also anchor vascular plants, hence allowing the shoot system to grow taller.
In Experiment 3.2, we have to make a slide of incest’s testis
(grasshopper) by using squash technique and preparing a slide for observing under light microscope. First, we have to choose a male grasshopper to be examined. Then we have to pin it on the blue wooden board. Next, by using dissecting knife, we cut of longitudinally its abdomen and the testis (needle-like shape) is taken out by using forceps and it was placed on the glass slide. Then we added several drops of acetin-orcein stain and put on the cover slip. The observations were portrayed it in the Table 3.2.
The precautions steps that we should engage in the slide-making process are we have to cut as thin as possible the plant tissue so that it will be easier t o observe under light microscope. Furthermore, for experiment 3.2, once should cut the insects abdomen longitudinally using a knife. Besides that, during preparing a slide, it has to be warmed up 10 s on Bunsen burner accurately.
CONSLUSION
Using hand-cutting method for making a thin slice of tissue sample is not the best way as the thinness of the tissue probably cannot be obtain accurately.
INTRODUCTION
Examining thin section of specimens using light microscope will be the major tool to study cells, tissues and organ morphology. Histology involves the preparation of the tissues for examination using a microscope.
Light microscope utilizes specific arrangements of lenses to magnify an
image. An electric bulb is the light source used to illuminate the tissue section. The image is further magnified by the ocular lens of the eyepiece. This lens focus the image on the retina of the eye. The total magnification of the image depends in the magnifying powers of the objectives lens and that of the ocular lens.
Quality of the image depends not only on magnifying capability of the lens but also on its resolution. The resolution means of the lens to show that two
