Essays Tagged: "Cell membrane"

"The Living Cell"

I'd recommend turning this paper in first! Good Job!!!!!THE LIVING CELLThe cell is the smallest unit of living matter that can exist by itself. Some plants and animals ... st unit of living matter that can exist by itself. Some plants and animals consist of only a single cell. Others are composed of billions of cells.Cells exist in a variety of shapes and sizes. They ma ... a variety of shapes and sizes. They may, for example, be cube- shaped or flat. Scientists who study cells have determined that a single cell may be as large as a tennis ball, or so small that thousand ...

(2 pages) 70 0 4.6 Nov/1996

Subjects: Science Essays > Biology

"Experiment to investigate the effect of osmosis in potatoes" A GCSE experiment looking at the effects of the concentration of sucrose solution on osmosis in potato tubers.

s in PotatoesThe aim of this experiment is to investigate the movement of water in and out of plant cells. The cells chosen for study will be taken from potato tubers. Firstly I will explain what osmo ... nes are very thin layers of material which allow some things to pass through, but prevent others. A cell membrane is semi permeable. They allow small molecules like oxygen, water, amino acids etc. to ...

(11 pages) 191 1 4.7 Jan/2003

Subjects: Science Essays > Biology

The effects of Cystic Fibrosis.

Cystic fibrosis is a disease that affects the way salt and water move in and out of the body's cells. The main areas affected by this disease are in the lungs and the digestive system, mainly the ... rane conductance regulator), which is important in the regulation of how much salt moves across the cell membrane. For normal functioning of the lungs, there needs to be a certain amount of fluid and ...

(3 pages) 42 0 5.0 Apr/2003

Subjects: Humanities Essays > Health & Medicine > Diseases

Surface Area to Volume Ratio and the Relation to the Rate of Diffusion.

olume ratio in living organisms is very important. Nutrients and oxygen need to diffuse through the cell membrane and into the cells. Most cells are no longer than 1mm in diameter because small cells ... no longer than 1mm in diameter because small cells enable nutrients and oxygen to diffuse into the cell quickly and allow waste to diffuse out of the cell quickly. If the cells were any bigger than t ...

(5 pages) 64849 1 3.0 May/2003

Subjects: Science Essays > Biology

Diabetes Types 1 and 2 thoroughly explained

b glucose so it can be used as a source of energy. The condition may also develop if muscle and fat cells respond poorly to insulin. In people with diabetes, glucose levels build up in the blood and u ... iate level of insulin to help absorption glucose builds up in the blood because it cannot enter the cells. When the blood passes through the kidneys, organs that remove blood impurities, the kidneys c ...

(5 pages) 193 0 3.0 Jan/2004

Subjects: Humanities Essays > Health & Medicine > Diseases

Practical assesment about biology: To determine the water potential of potato tuber cells

OSMOSISAimTo determine the water potential of potato tuber cells.Background knowledgeOsmosis is defined as the movement of water molecules from a region of hig ... ecules. Here, water molecules are constantly moving in a random fashion. Some of them collides with cell membrane, cell wall, creating a pressure on it known as water potential. The higher their kinet ... fore, the nearer the value to 0 Kpa, the higher the water potential.Potato tubers are made of plant cells. Plant cells always have a strong cell wall surrounding them. They also contain partially perm ...

(14 pages) 125 0 3.9 Feb/2004

Subjects: Science Essays > Biology

Respiration

it carbon dioxide. the term respiration is also used to refer to the liberation of energy, within a cell. from fuel molecules such as carbohydrates and fats. Carbon dioxide and water are the products ... ates and fats. Carbon dioxide and water are the products of this process, which is sometimes called cellular respiration to distinguish it from the physical process of breathing.Small organisms of the ...

(2 pages) 46 1 3.4 Feb/2004

Subjects: Science Essays > Biology > Human Biology

Biology Basics: Homeostasis

centration to regions of low concentration. It is a method of passive transport, and thus costs the cell no energy. Electrically charged ions and large molecules will not diffuse freely across the mem ... eely across the membrane.Facilitated diffusion is used for molecules that can't diffuse through the cell membrane because they are too large or not soluble in the lipid bilayer. Proteins in the membra ...

(2 pages) 63 0 4.6 Apr/2004

Subjects: Science Essays > Biology

Investigation into osmosis in potato cells.

he concentration is equal on both sides of the membrane.Before OsmosisAfter OsmosisOsmosis in Plant CellsWater moves from cell to cell in plants by osmosis. The cell membrane of a plant cell is select ... l to cell in plants by osmosis. The cell membrane of a plant cell is selectively permeable. So if a cell containing a weak solution (lots of water) is next to a cell with a stronger solution (less wat ...

(9 pages) 76 1 3.0 Apr/2004

Subjects: Science Essays > Biology

Osmosis

9.1 PLASMA MEMBRANEI. All cells must maintain homeostasis in order to live.- they do this by controlling what materials can en ... omeostasis in order to live.- they do this by controlling what materials can enter and leaveII. All cells have a plasma membrane that is SELECTIVELY PERMEABLE - this only allows for specific things to ... embrane that is SELECTIVELY PERMEABLE - this only allows for specific things to enter and leave the cellA. Selective permeability is achieved by the structure of the plasma membrane (fig.9.3, pg 220)1 ...

(2 pages) 39 0 4.3 May/2004

Subjects: Science Essays > Environmental Science

What is the effect of temperature on the permeability of beetroot cell membranes?

changing in the experiment. I want to find out what effect temperature has on the permeability of a cell membrane.Controlling other Variables- I will use measures to ensure that everything stays the s ... ts and plot a graph.EvaluationMy results show that temperature affects the permeability of beetroot cell membranes and makes it more permeable with a higher temperature. The graph shows how the colour ...

(3 pages) 86 0 5.0 Jun/2004

Subjects: Science Essays > Biology

The Effect Of Temperature On a Cell Membrane's Permeability

hat effect an increase in the surrounding temperature has on the plasma membrane of a typical plant cell structure.Hypothesis:An increase in temperature will damage and denature the plasma membrane an ... oplasm and other substances contained within the membrane to leak out.Introduction:The purpose of a cell membrane is to control the transport of substances moving into and out of a cell. The membrane ...

(5 pages) 111 0 4.7 Jun/2004

Subjects: Science Essays > Biology

Study guide chapter 8 for AP Bio (Biology by Campbell and Reece)

e Structure and Function1. Phospholipids consist of a hydrophilic head, and a hydrophobic tail. The cell membrane is a phospholipid bilayer two membranes thick. The bilayer is a stable boundary betwee ... omes solid. When a membrane solidifies, enzymatic proteins in the membrane may become inactive.a. A cell can change the lipid composition of their membranes as an adjustment to changing temperature. F ...

(4 pages) 39 0 4.3 Oct/2004

Subjects: Science Essays > Biology

Animal Cells

Animal CellsAnimalCellsMy cell is the animal cell It really depends on which cell you are talking about - d ... lly depends on which cell you are talking about - different cells do different things. Such as skin cells. They form a barrier on the outside of the body which protects the organs and tissues inside. ... damaged by bumps and knocks and also prevents bacteria and viruses from getting into your body. The cells structure, contains the CellMembrane keeping the cell together and controlling what substances ...

(2 pages) 28 0 4.0 Nov/2004

Subjects: Science Essays > Biology

Bacteria

* Bacteria- Bacteria are cells that are big enough to be seen under a light microscope.- Bacteria are found everywhere: - in ... d others are harmful that cause diseases such as pneumonia, tuberculosis, scarlet fever.- Bacterial cell: has a cell wall, cell membrane, a loop of DNA.Cell WallCell MembraneLoop of DNA*Bacterial grow ... eria can be grown in sterile conditions in the laboratory.- A colony of bacteria starts with just 1 cell.- It divides into 2 cells, then the 2 divide into 4, then the 4 divide in to 8, then the 8 divi ...

(2 pages) 26 0 1.0 Dec/2004

Subjects: Humanities Essays > Health & Medicine

Essay on Bacteria; Includes Bacteria, Eukaryotic Cells, Cell membrane, etc..

sage is small enough. Some bacteria can even form a slime layer on themselves acting almost like a "cell membrane", choosing what goes inside the bacteria and out. Bacteria are very adaptable and can ... nside the bacteria and out. Bacteria are very adaptable and can survive in almost any condition.Why Cells are Microscopic: Smaller cells function more efficiently than bigger cells. In the body ...

(2 pages) 69 3 3.0 Dec/2004

Subjects: Science Essays > Biology

Investigation to find the effect of different concentrations of sugar solutions on osmosis

low concentration, until both sides are equal (have reached equilibrium).This can be seen in living cells. The cell membrane in cells is semi-permeable and the vacuole contains a sugar/salt solution. ... tilled water (high water concentration) water will move across the semi-permeable membrane into the cell (lower water concentration) by osmosis, making the cell swell. This cell is now referred to as ...

(5 pages) 34 1 4.4 Jan/2005

Subjects: Science Essays > Biology

AT1- Osmosis In Potatoes

region of low concentration, until the two concentrations are equal in concentrations of water.Many cell membranes behave as semi permeable membranes, and osmosis is a vital mechanism in the transport ... living organisms, for example, in the transport of water from the soil to the roots in plants.If a cell is in contact with a solution of lower water concentration than its own contents, then water le ...

(8 pages) 33 0 3.0 Jan/2005

Subjects: Science Essays > Biology

BEETROOT

iment is designed to investigate the effect of varying temperature (centigrade) on beetroot and its cells.My earlier experiment suggest that as temperature increases the integrity of the beetroot cell ... ortant to insure the sample sizes are the same.Temperature: As temperature will affect the beetroot cell membrane, I will keep the temperature constant throughout the experiment by using a water bath ...

(4 pages) 44 0 4.0 Jan/2005

Subjects: Science Essays > Biology

Beetroot cell membranes

ortant to insure the sample sizes are the same.Temperature: As temperature will affect the beetroot cell membrane, I will keep the temperature constant throughout the experiment by using a water bath ... and insure that pH does not become a variable. PH is important for maintaining the integrity of the cell membrane as integral proteins can denature upon change in pH. Also, presumably the buffer will ...

(4 pages) 31 0 0.0 Feb/2005

Subjects: Science Essays > Biology