14 IB Biology Cell To Cell Communication Unicellular and multicellular organisms need to sense their environment in order to survive. Unicellular organisms need to be able to differentiate between poisonous foods and to avoid predators. Cells release chemical messengers to communicate. They communicate either by paracrine signaling or gap junctions. Local signaling in animals is called paracrine signaling. While gap junction is the direct contact between cells. There
Words: 369 - Pages: 2
SUMMARY CBH Ex I CELLS AND ORGANELLES Cell Membrane: consist of a lipid bilayer. Hydrophobic tails are located in the interior. Transmembrane protiens are anchored to the core of the bilayer and can be removed only by detergents that disrupt the bilayer. Peripheral membrane proteins are attatched to the cell surface electrostatically and are easily removed by altering the pH. Eucaryotic cells with outer- and intra- cellular membranes ~ half the cell’s total volume -separate intracellular
Words: 3311 - Pages: 14
are about one hundred trillion of them in our bodies, each so small that several thousand could fit on the period at the end of this sentence. They make up all our tissues muscle, bone, blood which in turn make up our organs. Under the microscope, a cell looks a lot like a fried egg: It has a white (the cytoplasm) that’s full of water and proteins to keep it fed, and a yolk (the nucleus) that holds
Words: 414 - Pages: 2
Outline the function of the main cell components. Cell membrane: Cell membrane controls the movement of substances of substances into and while keeping other substances out of the cell. The basic function of cell membrane is to protect the cell form the surroundings. Cell membrane also helps support the cell and help maintain its shape. Nucleus: Nucleus contains genetic material which controls the activities of the cell. The nucleus controls many functions in the cell by controlling protein synthesis
Words: 564 - Pages: 3
ADVANCED BIOLOGY RESOURCES FOR CARIBBEAN STUDENTS UNIT 1 BIOLOGY WORKSHEET ONE TIME : 2 ½ hours permitted CAPE BIOLOGY RESOURCES 12/16/2011 -2- SECTION A Answer ALL questions. You must write your answers in the spaces provided. 1 (a) Figure 1 below is an electron micrograph of an animal cell. (i) On the figure, identify the structures labeled A, B ,C and D Figure 1. Electron micrograph of an animal cell [3 marks] (ii) With reference to the structures labeled in Figure 1 which structure
Words: 1701 - Pages: 7
The Effect of Temperature on the Cell Membrane of Beetroot Cells To investigate whether temperature will damage and denature the plasma cell surface membrane of beetroot cells. Background Information. In spite of their many differences in function and appearance, all cells have a surrounding membrane (called the plasma membrane). The purpose of a cell membrane is to selectively control the movement of substances into and out of the cell. The membrane is made of 40% lipids, 0-10%
Words: 1017 - Pages: 5
The Living Cell A cell is the smallest structural unit of an organism that is capable of independent functioning. All cells start life with a plasma membrane, cytoplasm, organelles, and DNA. Cells vary in size and also in what job function they have. Cells are complex but highly organized. They contain a number of internal structures. A cell’s plasma membrane is the cell’s outer membrane. It separates the cell from the external area. The cell membrane surrounds the outside of both Eukaryotic
Words: 293 - Pages: 2
Cytoplasm Cytoplasm is basically the substance that fills the cell. It is a jelly-like material that is eighty percent water and usually clear in color. It is more like a viscous (thick) gel than a watery substance, but it liquefies when shaken or stirred. Cytoplasm, which can also be referred to as cytosol, means cell substance. This name is very fitting because cytoplasm is the substance of life that serves as a molecular soup in which all of the cell's organelles are suspended and held together
Words: 2624 - Pages: 11
October 29, 2012 Chapter 4 1. Why cells are small? The surface-area-to-volume ratio requires that cells to be small. Smalls cells are likely to have an adequate surface are for exchanging wastes for nutrients 2. Microscopy today: different types of microscopes. Amoeda, light microscope. Transmission electron micrograph, scanning electron micrograph 3. Prokaryots vs. eukaryotes. The Structure of Bacteria. Eukaryotic Cells: Organelles. Prokaryotic lack a membrane
Words: 402 - Pages: 2
– found in animal cell membranes, stabilizes membranes at warm temps and keeps membranes fluid at lower temp MEMBRANE PROTEINS – function 1) help maintain cell shape and coordinate changes inside and outside cell via attachments to cytoskeleton and extracellular matrix 2) receptors for chemical messengers from other cells 3) function as enzymes 4) Glycoproteins involved in cell-to-cell recognition 5) may participate in intercellular junctions that attach adjacent cells to each other
Words: 2290 - Pages: 10
