Animal And Plant Cells, View Them Under A Microscope And Document What Was Seen

In this experiment first the stages of an onion cell undergoing mitosis are going to be observed and every stage is going to be detected and drawn on paper. A brief description to what is going on should be attached to the pictures. This is important to understand the basics of cell division which is necessary growth,repair and asexual reproduction. Second the number of cells undergoing each phase is going to be counted to figure out in which phase the cell remains the most. If interphase is the stage in which the cell grows and prepares for cell division then the

Preparing specimen for electron microscope hard, light microscope still very useful as a window on living cells.

Cytoplasmic streaming was measured 4 times after flushing the cells with pond water, at 5 minute intervals

Tetrahymena in the 5% ink showed a higher stained vacuole count that those in 1% ink. This supported our hypothesis that the Tetahymena in a higher concentration of ink would show more staining, because there is more ink around for them to consume. Differing results were found in a similar experiment by Bazzone (2000), as cells in a higher ink concentration showed fewer vacuoles than those at a lower ink concentration. This experiment followed the same procedure, but expanded the ink concentrations to include 10% ink and examined cells at the timepoints 2, 10, 20, and 30 minutes (Bazzone, 2000). This study did not find an explanation for why these results occurred (Bazzone, 2000). Since our numbers of vacuoles of 1% and 5% ink were nearly identical for each time period, it is possible that if we repeated the experiment and counted more

Wischusen, William, Jolissaint, Ann, Reiland, Jane, and Pomarico, Steven. 2012. Biology 1208/1209: Biological Laboratories for Science Majors. Hayden McNeil, Plymouth,

Abstract: The purpose of this lab is to separate and identify pigments and other molecules within plant cells by a process called chromatography. We will also be measuring the rate of photosynthesis in isolated chloroplasts. Beta carotene, the most abundant carotene in plants, is carried along near the solvent front because it is very soluble in the solvent being used and because it forms no hydrogen bonds with cellulose. Xanthophyll is found further from the solvent font because it is less soluble in the solvent and has been slowed down by hydrogen bonding to the cellulose. Chlorophylls contain oxygen and nitrogen and are bound more tightly to the paper than the other pigments.

To observe mitosis in onion root tip cells and record the different phases of mitosis.

Lab Manual    Introductory Biology (Version 1.4)    © 2010 eScience Labs, LLC  All rights reserved  www.esciencelabs.com • 888.375.5487    2  Table of Contents:    Introduction:          Lab 1:   The Scientific Method  Lab 2:   Writing a Lab Report  Lab 3:  Data Measurement  Lab 4:  Introduction to the Microscope    Biological Processes:            Lab 5:   The Chemistry of Life 

diH20 acted as a negative control in the experiment, all cells, both in intrafollicular zone and in interfollicular zone stained purple. Cells stained brown in the negative control indicate non-specific staining.

The observation under the microscope of a cell of an onion skin soaked for 15 minutes in a 0.5 molar sucrose solution showed a cell membrane just beneath the cell wall. The cell wall had a rectangular shape. See diagram 3 for sketch. The cell and its surrounding were in an isotonic solution. The two solutions in the cell and out (0.5 molar sucrose solution) of the cell were homogenous. No net movement of water and change in the cell structure was observed. The components of the solute and solvent were evenly intermixed. The concentration of solute and solvent on either side of the cell membrane was equalized. Because the onion tissue didn’t get any water the cell was flaccid and nonturgid.

Plants are organisms that can reproduce sexually through meiosis and create more cells through mitosis (Russell et al. 2013). For studying mitosis, the common onion is an ideal choice. Because it is easy for onions to germinate without soil, it is easy to control any substances provided to the plant. The onion root tips are only a few cells thick and grow quickly making them ideal for time efficiency. The onion root tip needs to be squashed between the cover slip and the microscope in order to reduce the slide preparation’s total depth. To dye condensed chromosomes, such as those undergoing mitosis, a stain is used to make

P1 – Describe the microstructure of a typical animal cell and the functions of the main cell components. A typical animal cell is seen as a tiny, three dimensional sac which is in fact made up of many components, each as important as the other. The microstructure of an animal cell was in fact uncovered mainly through the use of both cell fractionation and electron microscopy. Each main component has its own, individual function which helps a cell to function and maintains the cell membrane. The components that I will be describing include the cell membrane, nucleus, cytoplasm, mitochondria, lysosomes, Golgi bodies, centrioles, endoplasmic reticulum (both smooth and rough) and ribosomes.

Making the onion tip root cell slide was successful. Our results supported the hypothesis because we saw cells in the onion root tip in prophase, metaphase, and anaphase. As we went up in power objectives, each phase of the cell became more definitive. The cell root was a great indicator of the structures of the different cycles of the cell. This is important because we will be prepared for future labs working with the microscopes and can now adjust it for the best view of the slide. We practiced working with the compound light microscopes and different phases of the cell cycle. Onion root tips are useful to observe mitosis because the cells are frequently diving as the root grows. So when we stained the cell, we caught many cells in different phases. The significance of this lab was to better understand the process and stages of mitosis and meiosis and compare and contrast the mitotic process in plants and animals. We grasped the concepts of what the chromosomes look like, and what they look like in each step of the processes. Having read much about mitosis and meiosis, seeing these cells was the real application of describing and understanding the stages.

There were many tiny cells, but they were very hard to see. The cells were dark and clumped together.

But first, let us talk about the discovery of cells and the cell theory. Robert Hooke, an english scientist, was the man who first discovered the cell in 1665, proof being a book he released at that time called Micrographia. In this book, Hooke gave 60 observations of random objects under a compound microscope with a magnification of 30x. Because of this, he was not able to see the internal structures in the cell, like nuclei and vacuoles, and what he proclaimed to be cells were just empty cell walls of plant tissues. He shared his observations with The English Royal Society, until they started receiving letters from a scientist named Anton van Leeuwenhoek. The letters stated that Anton made use of a microscope containing improved lenses that magnified objects up to 275x, enough to identify the living parts of a cell. He kept on sending