LAB Report BIO411 Cell Biology PDF

Preview

Summary

Download LAB Report BIO411 Cell Biology PDF

Description

UNIVERSITI TEKNOLOGI MARA PAHANG FACULTY OF APPLIED SCIENCES

Bachelor of Science (Hons) Biology BIO411 – Cell Biology Semester 1 2020/2021 LAB REPORT 1, 2, AND 3

NAME

STUDENT ID

NUR ANIZA BINTI AHMAD MARNI

2021149813

ROHAYU BINTI JUNAID

2021132545

WAN AMEERA AMALIN BINTI WAN

2021132491

MOHD ASRI

GROUP: AS2011A LECTURER’S NAME: MADAM SARINA BINTI HASHIM DATE OF SUBMISSION: 21 JUNE 2021

INTRODUCTION “Micro” means small, and “scope” means vision or glance. Microscopes are specialised optical equipment that make enlarged visual or photographic images of objects or specimens that are too small to be seen with the eye, including digital images. During this experiment, the plant cells and human cells are observed employing a compound microscope. A compound microscope is employed to look at samples at high magnification (40x-1000x) using the combined effect of two lenses (the ocular lens and also the objective lens). Always raise a light microscope by both the arm and therefore the base at an equivalent time when transporting it. It is important to know the functions of every component on a light microscope. (Mokobi, 2020)

PART Eyepiece

FUNCTION The ocular is another name for the eye. This is the component of the microscope that is used to see through it. It's at the very top of the microscope. The normal magnification is 10x, however an alternative eyepiece with magnifications ranging from 5X to 30X is available.

Objective lenses

These are the most common specimen visualisation lenses. Their magnification ranges from 40x to 100x. On a microscope, there are around one to four objective lenses, some of which are rare

facing and others which face forward. The magnification power of each lens is different. Head

It houses the optical components of the microscope's upper section.

Base

It serves as a support for microscopes. It's also contain the microscopic illuminators.

Arms

This is the portion of the microscope that connects the base to the head and the eyepiece tube. It supports the microscope's head and is also utilised when transporting the microscope. This high quality microscopes have an articulated arm with many joints that allows the microscopic head to move more freely for improved viewing.

Nose piece

The spinning turret is another name for it. It contains the objective lenses. It can spin the objective lenses based on the magnification power of the lens because it is moveable.

Adjustment knobs

These are the knobs that control the microscope's focus. Fine adjustment knobs and coarse adjustment knobs are the two types of adjustment knobs.

Stage

The part on which the specimen is displayed and which can be moved by turning the coarse adjustment knob.

Condenser

Light from the illuminator is collected and focused through lenses into the specimen.

Illustrator

The light source for the microscope is positioned at the base and collects light from an external source of roughly 100 volts.

APPARATUS AND MATERIALS Method 1: Light microscope, lens paper, lens cleaner and a slide of a specimen. Method LAB 1A: Mountant (water), cover slips, slides, tissues, forceps, dissecting needles and work surface. Method LAB 1B: Cover slip, glycerine, glass slides, onion, watch glasses, distilled water, Safranin solution, forceps, brush, needle, blotting paper and a dropper. Method LAB 1C: Tooth pick, cover slip, Methylene blue solution, glycerine, glass slide, distilled water, brush, needle, filter paper and a dropper.

PROCEDURE Method 1 1. A microscope was retrieved from the cabinet and the cord from the back was unwind and the microscope was plugged in. and turned on. 2. The ocular lenses were checked and the number 64 line was aligned with the white line below the rotating part of the lens. The objective lens was being put on low power and the stage was moved to its highest position. 3. The light was adjusted to the medium or medium high range and the microscope slide was put in place by the stage clip. The slide was put in the centre over the condenser by turning the knobs on the lower right side of the stage. 4. The observation of the specimens was started with the low power objective lens (4x), continue with next highest objective lens (10x) and the highest power lens (40x). 5. The lenses were cleaned by wiping the lenses using a lens paper soaked with lens cleaner and drying the lenses using a clean lens paper when the specimens were difficult to focus. 6. When the observation of the specimen completed, the slide was removed, the lowest power lens was rotated in place, the light was turned off and the microscope switched and plugged off. Method LAB 1A 1. A slide was placed on the work surface and a drop of water was being put on the slide. 2. A leaf from the Elodea plant was placed on the slide and a cover slip was positioned on the top of the slide to cover the leaf. Some drops of mountant might be placed on the corner of the slide when needed. Method LAB 1B 1. Some distilled water was poured into a watch glass and a piece of transparent onion peel was removed from an onion using the forceps. 2. The epidemis was placed into the watch glass containing distilled water. A few drops of Safranin solution were dropped using a dropper into another watch glass. 3. The onion peel was transferred using a brush into the watch glass containing Safranin solution and the peel was kept in the solution for 30 seconds to make sure the peel is stained. 4. The peel then was moved back using the brush into the watch glass containing distilled water.

5. 2-3 drops of glycerine were placed in the middle of a dry glass slide using a dropper and the peel was transferred using the brush to the slide containing glycerine. A cover slip was placed carefully on top of the peel with the help of a needle. 6. Excess glycerine was removed from the slide using a blotting paper. Method LAB 1C 1. Some distilled water was poured from the bottle into a glass slide. The inner side of the cheek was scrapped with a clean toothpick. 2. The cheek tissue was rubbed on the glass slide containing water and the mixture was mixed using a needle to spread it out. 3. A few drops of Methylene blue solution were added using a dropper to the mixture on the slide. Excess water and stain were removed using a blotting paper after 2-3 minutes. 4. A few drops of glycerine were added into the mixture using a dropper and a clean cover slip was lowered carefully on the mixture with the help of a needle. Using a brush and needle, the cover slip was gently pressed to spread the epithelial cells. 5. Any extra liquids around the cover slip were removed using blotting paper.

RESULT Plant Cells

Elodea cells 400X magnification

Onion cells 400X magnification

Human Cells

Cheek cells 400X magnification

DISCUSSION Structure

Elodea cells

Onion cells

Cheek cells

Shape

A box-like

A brick-like

A rounded

Size of nucleus

Absent

Small nucleus

Large and prominent nucleus

Cell wall

Present which is

Present which is

Absent

made of cellulose

made up of cellulose

Vacuole

Large vacuole

Large vacuole

Absent

Chloroplast

Present

Absent

Absent

Cell membrane

Present

Present

Present

The different types of cell structures have their own specific functions. Cell wall is an outer thick layer in cells of plant (elodea and onion) that provide additional support and protection against physical damage, pathogens that are attempting to attack the cell and also gives the cell its shape to allow the organism to their shape. The nucleus controls and regulates the activities of the cell like development and metabolism. It also carries the genes, structures that contain the genetic information. The vacuole plays a vital part within the homeostasis of the plant cell. It is indulged in separating materials that may be destructive or a risk to the cell, maintaining an acidic inside pH and keeping up inside hydrostatic pressure within the cell. Chloroplasts that found in plants are the sites of photosynthesis. This process converts solar energy to chemical energy by absorbing sunlight and utilizing it to drive the synthesis of organic compound like sugars from carbon dioxide and water. The cell membrane which present in both in plant and human cells give protection for a cell and provide a fixed environment interior the cell, which membrane has a few distinctive functions like transporting nutrients into the cell and also transporting harmful substances out of the cell. Onion cells and cheek cells need to be stained first in order to enhance visualization of the cell under a microscope and highlight metabolic processes or distinguish between live and dead cells in a sample. Safranin stains onion cell by binding to acidic proteoglycans in cartilage tissues with a high partiality forming a reddish orange complex. The binding made cartilage tissues show up red when observed under a microscope. While methylene blue stain is used in the cheek cells. Methylene blue contains a string liking for both DNA and RNA. The nucleus at the central part of the cheek cell contains DNA meanwhile methylene blue contains a positive charge. Hence, when DNA comes in contact with methylene blue, their opposite charges draw in which causing methylene blue's "rings" to slide in between the ‘rungs’ of the DNA ‘ladder’. As a result, the nucleus at the central part of the cell is much darker than its surrounding. The cheek cells are squamous epithelial cells from the external epithelial layer of the mouth and lots of the tiny speckles that present in the cheek cells. These tiny speckles are bacteria mostly found from tongue and teeth. The large number of bacteria they harbour is likely a reflection of the large masses of bacteria which dwell within the tongue invaginations. Cell staining is the most vital method in the cheek cell in order to distinguish the different parts of the cell. Methylene blue encompasses a string liking for both DNA and RNA. When a drop of methylene blue is applied, the whole cell appears light blue in colour which identify as a cytoplasm while the central part of the cell is a darker blue spot as known as nucleus.

CONCLUSION In conclusion, the ability to determine the functions and parts of compound microscopes are achieved, attained understanding of the proper use and the maintenance of the light microscope and learned to observe a wet mount slide preparation for plant cells.

REFERENCES 1. Mokobi, F. (2020, March 3). Parts of a microscope with functions and labeled diagram. Microbe Notes. https://microbenotes.com/parts-of-a-microscope/.

INTRODUCTION Cell staining is a technique that allows you to visualize cells and cell components more clearly under a microscope and the ability to determine the shape and type of cells. One can preferentially stain selected cell components, such as a nucleus or a cell wall, or the complete cell by applying different stains. Most stains can be used on fixed and non-living cells, but only a few on alive cells while other stains can be used on both living and non-living cells. Staining cells can also help to highlight metabolic activities or distinguish between living and dead cells in a sample. (Bruckner, 2021)

MATERIALS AND METHODS Lab 2 Task 1- Blood Smear preparation and staining: Materials: Blood sample, glass slides, Leishman’s stain, distilled water, droppers, petri dish, compound light microscope, immersion oil, cotton, 90% alcohol and blood lancet. Methods: Two glass slide and finger were cleaned with 90% alcohol. A finger was pricked with blood lancet. A drop of the blood was placed at the centre of one corner of a glass slide and second glass slide used by touching a drop of blood while inclining the slide at a 45˚ angle. The inclined slide gently moved towards the other end of the slide. A smeared blood appeared roughly and dried for a minute. The slide was placed in a petri dish with blood smear facing up, several drops of Leishman’s stain was added and covered a petri dish. Alternatively, a coplin jar was filled with Leishman’s stain and the slide was immersed in the stain for a minute, the volume of distilled water was added twice to the stain. The water in the stain was properly mixed and set aside for 10 minutes. The slide was drained and washed with distilled water resulting pink in colour a blood smear, dried the slide and kept it in inclined position. The slide was observed under the microscope and at 400X, a drop of immersion oil was used. Lab 2 Task 2 - Calculate sperm concentration using a haemocytometer Materials: Haemocytometer, 3% saline, semen, pipette, phase contrast microscope, coverslips, humid chamber Methods: The semen was diluted by 3% saline and sample mixed thoroughly before counting. The coverslip was fixed in place over the counting chambers, 10 microliters of sample was aspirated by inserting tip of pipetted to the edge of the coverslip. The sample was ejected slowly in both two sides until it drowned up into the counting chambers. The haemocytometer was placed in humid chamber and set for 5 minutes. The sample was observed under phase contrast microscope. The unbiased count with biased was obtained at the 4 corners and a

centre square were selected for counting. 20X and 40X objectives were used and the number of sperms was determined by the loose heads of sperm within the smaller squares were counted and sperm lay on the centre line of the triple word line were counted on the upper of left-hand side of the square. The counts were kept tracked for each of five squares using a cell counter and the counts added together before progressing onto the second counting chamber. The sperm concentration was calculated by number of sperm/mL = average of both sides x 5 x dilution factor (400) x 10000 Lab 2 Task 3 - Mitosis in onion root tip experiment: Materials: onion, beakers, toothpicks, carnoy’s fixative solution, 70% ethanol, 1N HCl, acetocarmine staining, glass slides and coverslips, scalpel, petri dishes, containers, bunsen burner, blotting paper, droppers, forceps and scissor, compound light microscope and immersion oil Methods: the onion was fixed on a beaker containing tap water using toothpicks and the base of onion were touch the water level and kept for couple of days. The root tips were cut out for 1cm and transferred in to a container containing carnoy’s fixative solution and left for 48 hours. A few root tips from carnoy’s fixative solution was transferred into petri dish that containing 1N HCl, warmed for 5 seconds using Bunsen burner and exposed the root tips in the acid for 2 minutes. The root tips were cleaned in distilled water and transferred the root in petri dish containing acetocarmine staining, the stained was warm for 5 seconds and leaved the root tips in stain for 5-10 minutes. The root tip was transferred onto a glass slide containing a drop of water and 1mm of root tip was removed by scalpel. The coverslip was lowered on the sample and tap on it gently by forceps. The properly squashed slide appeared faint cloudy pink and observed under microscope by using immersion oil under 100X objective.

RESULTS TASK 1 Name

Structure

Red Blood Cells Magnification: 1000x

Concavity (lighter stained central area)

Red blood cells

Platelets Magnification: 1000x

Platelets

Neutrophil Magnification: 1000x Chromatin strand

Cytoplasmic granules

Nuclear lobes

Cytoplasm stains neutral pink while nucleus deep blue

Eosinophil Magnification: 1000x Bilobed nucleus

Acidophilic cytoplasmic granules

Basophil Magnification: 1000x

Basophilic cytoplasmic granules

Nucleus and cytoplasmic granules heavily stained deep purple by basic dye

Monocyte Magnification: 1000x

Monocyte

Purple stained nucleus

Lymphocyte Magnification: 1000x Nucleus stains deep purple, cytoplasm light purple

Lymphocyte

TASK 2

The field of view of a square observed under the microscope

SPERM CONCENTRATION TABLE Counts Sample

Calculation

Side 1

2

3

4

5

Sum Average

58 43

37

49

42

229

A

2

49 42

45

47

52

235

232

spm/ml

232 x 5 x 400 x 10000 =

1

Conc.x106

4640

4640 x 106

TASK 3 Stages

Diagram

Interphase Magnification: 100x Chromatin Cells are easily identified by their Nucleolus

prominent nucleoli. Nuclear envelope

Prophase (early) Magnification: 100x

Chromosomal condensation initiates, giving the nucleus a ‘grainy’

Nucleolus Nuclear envelope

appearance. Nucleolus still visible Prophase (late) Magnification: 100x

Further chromosomal condensation results in thick

Chromatin has condensed into chromosomes, nucleolus is not visible

rope-like chromosomes, which begins to turn into chromatids and centromeres. Metaphase Magnification: 100x

Chromosomes align along metaphase plate.

Chromosomes are loosely aligned on the metaphase plate

Anaphase (early) Magnification: 100x

Chromosomes with separated sister chromatids begin to move away from metaphase plate,

Chromosomes

towards opposite poles in equal numbers. Anaphase Magnification: 100x Sister chromatids have been pulled apart and on either side of the cell

Sister chromatids reach the opposite poles in equal number

Telophase Magnification: 100x

Chromosomal decondensation starts. Chromosomes almost fully decondense to form original chromatin network.

Chromosomes

Late Telophase/ Early cytokinesis Magnification: 100x

Chromosomes individuality is lost, forming chromatin network. Nuclear

Growing cell plate

membrane and nucleolus reappears. Cell plate begins to form.

DISCUSSION In Task 1, blood cells are being observed under the microscope and the results show different components in the blood. Blood can be defined as a fluid that travels through the vessels of the circulatory system and carries nutrients and oxygen to various cells. Blood cells mainly consist of red blood cells (RBCs), white blood cells WBCs) and platelets cells (Connie Rye, 2016). These cells come from bone marrow. They begin their life as stem cells and mature into RBCs, WBCs, and platelets. In addition, there are three types of WBC, which are lymphocytes, monocytes, and granulocytes, and the main types of granulocytes are neutrophils, eosinophils, and basophils (Dean, 2005). RBCs or erythrocytes are specialized cells that circulate through the body and provide oxygen for the tissues. The red blood cells are biconcave and small and do not have mitochondria or a nucleus (Dean, 2005). These characteristics give RBCs to perform their role as oxygen transport. The size and shape increase the surface area-to-volume ratio and the absence of a nucleus gives additional space for haemoglobin, which is important to transport oxygen. The lack of mitocho...