• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Overview of Cells & Energy (Revision)

Extracts from this document...

Introduction

1.1 Cell Theory ________________ Robert Hooke(1665): Published first book on cells. Discovered cells when looking at cork under a microscope. Discovered cell structure of plants. Anton von Leewenhoek (1650-1700):Dutch. First observed protists. With a simple lens(x200), he observed unicellular organisms & nuclei. By using his ability to grind lenses, he greatly improved the microscope as a scientific tool. He discovered bacteria, protozoa and other small life-forms which he called 'tiny animals'. Mattias Schleiden(1838): Deduced theory of 'photogenesis' which states that all living things are made of cels or their derivitives. Theodore Schwann(1839): With Schleiden, Schwann deduced the cell theory- that all animals and plants are made of cells and that within an organism all the cells are identical. Discovered Schwann cells. Rudolph Virchow (1855): Deduced that all cells are created by other cells. Demonstrated that cell theory applies to diseased tissue as well as living tissue. Jansen: Invented compound microscope. Light Microscopes: Light from a source beneath the stage is transmitted through the two lenses in a series, the objective and the ocular (eyepiece) lenses to provide magnifications. Cannot resolve details better than about 0.2 mm(micrometers) ...read more.

Middle

1.3 Eukaryotic Cells ________________ Vocabulary: ATP: energy molecule used in active transport against the concentration gradient. Centrioles: vital for reproduction (production of spindle fibres) Chloroplast: contains chlorophyll and is present only in plant cells. Is involved in photosynthesis. Concentration gradient: difference of concentration between two substances Cytolysis: animal cell exploding Cytoskleteon: maintains in cell shape Endocytosis: food/liquid going into the cell Endosymbiosis: The theory that mitochondria and chloroplasts are descended from specialized bacteria. This is because these organelles both contain their own DNA and this DNA is present in a single, continuous molecule, like the DNA of bacteria. Many of the enzymes contained in the cell membranes of bacteria are found in the mitochondrial membranes. Also, they both have their own ribosomes that resemble those of bacteria. Mitochondria can only be produced by mitochondria, like cells from cells. Probably these organelles used to be simple bacteria and were swallowed up by bigger bacteria who could not digest them. In turn these organelles provided the cell with energy in return for protection etc. and turned into an organelle. Equilibrium: equal amounts moving in and out Exocytosis: waste going out of the cell Flaccid: animal cell shrinking Golgi Apparatus: stacks of flattened membranous sacs. ...read more.

Conclusion

Golgi apparatus- assembly point through which raw materials for secretion are funnelled, carbohydrate components are added, and then are shed from the cell. Lysosomes- destroy unwanted structures (e.g. old mitochondria), or entire cells by the rupturing of the lysosome membrane and the releasing of digestive enzymes (e.g. tadpole tails in frog metamorphosis). Mitochondria- concerned with the chemical reactions of aerobic respiration; i.e. energy is converted to ATP here (the inner surface is infolded to increase surface area). Nucleus- contains genetic information (bounded by a nuclear membrane). Chloroplasts- contain chlorophyll used in photosynthesis DNA in Prokaryotes Vs. DNA in Eukaryotes: DNA is loose in prokaryotic cells, in eukaryotic cells the DNA is contained within a nuclear envelope. DNA in prokaryotic cells is circular, in eukaryotic cells it is arranged in chromosomes Prokaryotic cells have about 1/1000 as much genetic material. Cell Reproduction: prophase separate when nuclear membrane disappears nucleolus disappears centrioles go to poles spindle fibers appear chromosomes get shorter and thicker metaphase centrioles become asters the chromosomes line up ?single file? at the equator spindle fibers attach to centromere with kinetochore anaphase the chromatids are pulled towards opposite poles telophase the nuclear membranes reappear nucleolus reappears asters become centrioles in animals spindle fiber disappears chromatids get longer and thinner and become chromatin. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our International Baccalaureate Biology section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related International Baccalaureate Biology essays

  1. Cell Membrane Structure and Function - revision questions and answers.

    substance and then the membrane pinches off to form an intracellular vesicle. How do vesicles interact with the plasma membrane and move substances into and out of the cell? They do so through pagocytosis (which digests large particles), pinocytosis (occurs when vesicles form around a liquid or around very small

  2. Testing the solute concentration of potato cells

    Overall seeing the mean and percentage change, it is considered good result. Despite the variation always accompanying to living organisms, the standard deviations are very low in that all trials have 0.2 cm except for one trial with even lower 0.1 cm.

  1. Biology Lab - frequency of cell division in animal and plant cell

    Table 2. Data collected while observing the prepared slides of whitefish blastula in class. Number of cells in phase was calculated by counting 20 adjacent whitefish blastula cells and the cell which are in interphase or actively dividing stage was determined.

  2. Penicillin - its discovery, properties and uses.

    medicine, they cannot define what component in mould that can remedy illness. Till 1600s, more and more knowledge in nature of medicine and also about antibiotics. One of the successful happened in 1884, a nurse in King's College Hospital had wounds that did not respond to any antiseptic, Lister gave Penicillium that cured her.

  1. IB Genetic Unit Notes

    Males however only have 1 X chromosome and if this X chromosome is affected then they will have colour blindness. Haemophilia is a disorder in which the blood will not clot normally and they experience continuous, excessive bleeding. There are two types - Type A and Type B.

  2. Experiment Colours of Light (Wavelength) absorbed by green plant

    0.43 1.87 1.91 Table 5: The table above shows the amount of absorption of wavelength by the mustard sample exposed to different wavelength, referred to standard solution and taken in 3 different trials. Qualitative Data Observations Both spinach and mustard are green in colour Both spinach and mustard becomes softer

  1. Differences between prokaryotic and eukaryotic cells

    Rough Endoplasmic Reticulum- Studded with numerous ribosomes, which give it its rough appearance. The ribosomes synthesize proteins which are processed here. Golgi Apparatus- Another series of flattened membrane vesicles, formed from the endoplasmic reticulum. It has a job of transporting proteins from the RER to the cell membrane for export.

  2. Effect of Detergent on Membrane Permeability

    1. Change in Absorption Rate Percentage of Detergent Delta Absorption Rate (AU) ±0.001 AU 0% (Distilled Water) 0.048 4% -0.152 8% -0.329 12% -0.070 16% -0.319 Sample Calculation: 4% Detergent ΔAbsorbance = Initial Absorbance – Final Absorbance ΔAbsorbance = 0.775 AU - 0.623 AU ΔAbsorbance = -0.152 Data Analysis & Graphs:

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work